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  1. (Sorry for the clickbait title) Here are some simple tips to help you take better photos of coins with your phone or camera. They require no additional equipment or skills. They are meant as starter tips, and you can build on and improve all of them with practice. Follow these tips and you should be able to take clear, bright photographs on just about any phone or camera, with no extra work before sharing. I have included some examples where the tips should have been followed. I have used my own photos, as well as a few that I have ‘borrowed’ anonymously from the forum. If anyone recognises their image and would like me to remove it, please let me know. I am not trying to shame anyone, just give advice. I will refer to ‘phone’ for brevity, but these tips also apply to cameras. And I will refer to ‘coin’ when these tips also apply to bars or any other small items. 1. Find a well lit space How: Simplest is near a window, preferably with net curtains or white blinds that allow lots of soft light through. Avoid normal room lights, clear light bulbs, and direct sunlight. And definitely avoid mixing different types of light, e.g. sunlight plus lamp. Why: You want plenty of bright and even lighting so your pictures won’t have noise (graininess) and you will be able to hold the phone still when taking the photo. Direct ‘hard’ lighting will produce glare and reflections that will be difficult to manage. Dark, back-lit. No details visible, and lots of grainy noise 2. Choose a suitable location How: Pick a plain, flat, dark background. Easiest is lying the coin flat on a table and photographing downwards. But you could put the coin on a stand or propped against something, for a little variety. Why: Dark backgrounds will emphasise the coin and distract less. You can use a lighter background with gold, but it really doesn’t work with silver. Dark is just easier and more forgiving. Although not terrible, the blue background is a little distracting and reflects some of the light from the coin 3. Remove dust and dirt How: Use a spectacle cleaning cloth or (gently) a clean cotton t-shirt, and clean the lens. Ideally use a lens cleaning solution / spray, to lift off the oils and protect the surface. Remove any dust, hairs, etc, from the coin. They might look tiny to the naked eye, but they will be really obvious in the photo. If you have a little hand dust blower, even better. Why: Fairly obvious, but easy to forget. A dirty lens will degrade sharpness and contrast. 4. Fix the colour, so gold looks gold and silver looks silver (I’ve done a series of tutorials on this subject alone, but here are the basics.) How: Simplest option is to look at the phone camera app and find a setting called “white balance”, “colour temperature” or some combination. It will almost certainly be on Automatic by default. Change this to an option that closely matches the light you are using, e.g. “daylight” or “cloudy”. Experiment until the pictures taken closely resemble reality. Why: Your phone will probably make a bad guess at what light you are using, because it can’t see the sky. You will need to help it, otherwise your gold coins can look washed out, possibly even blue or green, and your silver may also acquire random hues. If you really cannot get this to work, something that can help the phone in Automatic mode is to leave a white piece of paper in the shot, which you can crop out later (see below). Make sure it is white paper though, not cream or coloured. Believe it or not, this is a sovereign. The background is cream, so the automatic white balance has been confused and drained all the yellow away to make it 'white'. 5. Don’t have anything in the way How: If the coin is in packaging or a capsule that can be removed, do so. Even if you are unwilling to handle the coin, you can usually remove the top half of a capsule without touching the coin in any way. (Obviously, if doing so would damage or reduce the value of the coin, don’t do it.) Why: However clean and new a capsule is, it is another surface that will reflect light and gather dirt and dust. Also, phones have a tendency to try to focus on the capsule and not the coin, so you will not get a sharp picture. If it doesn’t need to be there, remove it for the photograph. Reflections, glare, scratches and dust in the capsule 6. Don’t get too close How: Hold the phone at least 30cm / 12” from the coin. Why: All phones have a minimum distance they can focus at. This varies by model, but a safe starting point is 30cm. If you go too close, the coin may be nice and big in the picture (see below why this doesn’t matter), but it won’t be in focus; this will ruin the shot. This is the top reason why we see so many blurry, out-of-focus coin images. 7. Don’t zoom How: Avoid using any physical or digital zoom feature of the phone. Just use the default options. Why: Unless you have a very steady hand, or are using a tripod, any zooming is likely to cause blur. Besides, digital zooming is just cropping anyway, and you are best doing that later (see below). The coin may look small in the image; don’t worry, it will look better after cropping. 8. Focus on the coin How: Modern phones usually have a feature where you tap on the part of the image you want to focus on. When you are ready to take the picture, do this. Why: Phones are built mainly for taking pictures of people, not coins. If it can’t see a face, it doesn’t always know what to focus on. Help it, and you will get sharper images. 9. Hold steady when taking the picture How: On a phone, use the side button to take a picture (often one of the volume buttons). This is steadier than tapping the screen. Why: Any movement as the photograph is taken will cause blur. 10. Straight and true How: The easiest photos to take, for the best results, will be straight at the coin’s face. It doesn’t need to be perfect, but stay within a few degrees of a right-angle. Why: Although you can add depth to a photograph by moving off axis, any significant deviation from straight will begin to introduce complexities that you may not want to tackle in a simple photograph. The biggest one will be focus, where you will find that one side of the coin is sharp and the other is blurred. Although out-of-focus areas can be aesthetically pleasing, people may assume you are trying to hide something 11. Trim away what doesn’t matter How: After you have taken the photograph, use the crop feature of your phone to remove the background around the coin, and effectively ‘zoom’ into the coin. Why: All modern phones have plenty of resolution to spare, far more than is visible on the screen itself. You can afford to crop out all the meaningless background, to make the coin bigger. This will mean that when you share the picture, more details will be visible. It’s your choice how tightly you crop, and whether you make the image square or the more traditional 4x3. Don’t be tempted to skip this step by holding the phone close enough to fill the picture with the coin. See above about getting too close. There was plenty of detail and sharpness in the coin, but all that wasted space means it is lost 12. Save and export at best quality How: Your phone app will probably have an option to choose what resolution and ‘quality’ to save images as. Always choose the highest. And when you finally share photos, if you have the option choose at least 800 pixels wide, preferably 1200 pixels. Why: Storing and transmitting images is effectively free and instant these days, as they don’t take up much space compared to, e.g. a movie or computer game. If you save with a low quality (especially JPEG) and low resolution, you are throwing away all that detail, sharpness and contrast. Also, it may introduce noise and even enhance blemishes that will make the coin look worse or even damaged. If you can, I recommend sharing images as PNG rather than JPEG. The image size difference isn’t really relevant these days, and it gives a perfect rendition of the original image without artefacts. The 'lumpy' lettering and emphasised dust is caused by a low quality JPEG export
  2. Here is a quick walkthrough of how I photographed a raw 'proof like' coin. I didn't want to handle it, so I kept it inside the capsule. Setting up the physical scene was fairly straightforward. I put the coin, in its capsule, on a slightly modified plastic stand. The modification is that I removed the small lugs that 'wrap' around the bottom of the coin and obscure the lower part. I also removed the top of the capsule, so that you don't get reflections, dust and loss of contrast. I was using a rotating stand as a floor, which is useful as it allows me to easily turn the coin so that I get just the right reflection. Then I take a series of identical photographs (in this case 12), where the only thing that varies is the focus point. Here are the first and last: Then I use focus stacking software to merge all the basic images together. It's automagical. The last 'phase' is some Photoshop work. Adjust the colour and exposure to match the lighting, pull down the blacks and shadows to isolate the coin. Then some clone tool work to remove the stand and capsule. Job done.
  3. This is a follow-up tutorial to: This is for those with a little more time, who want to get accurate and visually satisfying results with their photographs There are three main techniques here, which can be used independently or together. None of them are expensive; in fact the third one is free; but they do take a little effort and knowledge. 1. Using grey cards (‘gray’ for Americans) A ‘grey card’ is exactly that. A piece of card that is grey. A professionally produced photographic grey card, from a reputable vendor, will be fade-resistance and precisely calibrated to be a neutral colour, i.e. exactly balanced with no hue. For coins and other precious metals, I would recommend a small card, maybe 2x4 inches or thereabouts. Should definitely cost well below £10. A white card will also do well, although grey cards are easier to use and are less likely to fade or discolour over time. A piece of white paper may also help, but be wary as it is easy for the paper to be slightly off-white, and this will affect the colour balance significantly. At the other end of the scale, you can take it further and buy colour cubes, colour reference targets, and specialist software to calibrate your photographs. Those are beyond the scope of this tutorial - if you are in the market for those, I am not going to be teaching you anything here. There are basically 2 ways to use a grey card: a) reference shot, or b) in shot. Both have pros and cons. a) Reference shot Take photograph(s) of your coin(s) as normal, but just before or after, replace your coin with the grey card. Put the card in the same place, and at the same angle, and photograph it. This will provide you with a reference neutral colour, that you can then adjust to. Using photo adjustment software, you would then measure the correct colour balance or adjustments using the reference shot, and apply exactly the same to the real shot(s). There are too many different photography applications for me to cover exactly how to do this here, but you should find it under ‘white balance’. Advantages: the coin photograph is unaffected, you don’t need to recompose or move anything, and you should be measuring the exact same conditions because the card is in the same place as the coin. Disadvantage: takes a bit more time, needs post-processing software, should not be used when the lighting situation can change quickly, e.g. if you are using natural light, and a cloud covers the sun, it can make a dramatic difference. b) In shot Here, you include the grey card in the photograph with the coin. The card needs to be at the same angle and under the same lighting as the coin. Just widen the shot so that the card is in the frame. Once taken, you can crop out the card before sharing your final image. A variation of this is simply to use a white, lighter or grey background for the coin, but this is down to the desired aesthetics. Advantages: quicker, may enable the auto white balance feature of the camera to make a better ‘guess’, useful when the lighting conditions may change between photographs. Disadvantages: may be awkward to compose the image wider depending on space, should not be used if the lighting is very local, i.e. only the coin is lit, because the card would not be under the same conditions and the white balance may vary across the scene. 2. Photographic lighting This falls into 2 main categories, flashes and monitor lights. For the purposes of coin photography, flashes are unnecessary, difficult to use and expensive. So for this tutorial, I will focus on monitor lights. For between £50 and £150, depending on features and brand, you can buy a ‘monitor’, ‘video’ or panel light. It should have a high CRI value (90+), which is a measure of its colour accuracy and how natural it is. And it should either have a known fixed colour temperature, preferably around 5,600 Kelvin (daylight), or an adjustable temperature. (White balance is measured in temperature Kelvin - don't worry about it - just know lower numbers are yellower and higher numbers are bluer. For this tutorial, it doesn't matter.) Simply set it to a known value, set your camera’s white balance to the same value, and snap away. This should be all you need to do. A modification of this is to photograph in RAW mode, and then use software to set the white balance to the light’s known temperature afterwards - see below. If you do not shoot using RAW, adjusting the white balance later will always be harder and a compromise. You need to ensure that the monitor light is the only (or overwhelming) light in the scene. Lights in the room, through the window, etc, will all influence the photograph, and change the final colour. Also, lights will reflect off different surfaces of the coin, and produce odd colour patches. Therefore, you may want to invest in a light box to cut out all the other light sources. They are available for around £30 upwards, depending on size, or you can make one with a cardboard box and black cloth. Another consideration is that having a single light source can lead to bright spots, or undesirable highlights on the subject. This is especially a problem with precious metals that are prone to reflections. You can easily solve this by diffusing the light using cooking parchment (greaseproof paper), net curtains or similar material, or photographic diffusion paper (a little more expensive, but a neutral colour). Simply hang the diffusion material in front of the light, preferably making the light source bigger as a positive side effect. 3. Shoot RAW (This has nothing to do with whether you wear clothes while photographing. Although I strongly recommend it, as coins can be very reflective. 😁) This one is a bit more technical, but is free to implement. You just need some understanding of the principles. All but the earliest of cameras and phones, have the ability to shoot in what is called RAW. You can use free, 3rd-party camera apps, e.g. Open Camera, if necessary. You are doubtless familiar with JPEG files, the ubiquitous image files used everywhere, and by default your camera will generate JPEG files. However, JPEG files have several disadvantages. Lossy compression. Detail will be lost, and noise added, in order to compress the file to a smaller size. Worse still, every time you load the file into an editor, make a change and save it, the image will get worse. Narrow dynamic range. JPEG can store 8 bits (256 values) for each red, green and blue value in the image. Your camera is capable of capturing at least 10 bits, and the latest cameras 12-14 bits. So at best, three quarters of the possible range of values are thrown away, and possibly 98% is discarded. In-camera processing. An image, displayable in all browsers and devices across the world, needs to be produced. So certain safe, generic assumptions are made, and baked into the file. These include white balance, colour gamut, etc. Ultimately, you need to turn your photograph into a universally acceptable format, for sharing online, and JPEG is a perfectly adequate choice. You could use PNG, TIFF or numerous others. So, if you need to use JPEG anyway, what’s the advantage in shooting RAW? Firstly, for any work you need to do after the shot is taken but before sharing, i.e. post-processing, you should work in a format that does not degrade with each save, for obvious reasons. Secondly, and most relevant to this tutorial, shooting in RAW does not apply white balancing to the image. I will use a physical filter analogy. Each time an image is changed from the original, it is like adding a coloured filter to a light. You can’t take a filter away. So you add a filter, but then you need to correct it slightly, so you add another filter. And then you need to correct that, so you add another filter. So the incorrect white balance applied by your camera, needs to be corrected with another filter, which inevitably won’t be a perfect solution, so should then be corrected, again, etc. Instead, working with RAW files allows you to get everything right with the most original possible version of the image. RAW files should be immutable - any changes can be undone, or are saved separately, so the original is always preserved. Use a post-processing application (or phone app) to apply the right white balance to the image, get the exposure right, crop it, and when everything is right, save as JPEG and share. Summary Shoot in RAW if at all possible (top advice!). It makes everything else easier. Use a grey card to get an accurate reference for the white balance of the scene, especially if you are not in control of an accurate light source. Limit the number of different light sources. You may want to use a photographic light and/or a light box. Examples of colour calibrated photos of gold:
  4. The Problem Do you take photos of your lovely sovereigns, ¼oz Queen's Beasts, or (for the wealthier) 1oz gold bars and coins, only to find that they look like silver? Where has all the yellow gone? Why aren't my bargain coins selling? Why am I not as rich as my wildest dreams indicated? Gold ¼oz Eagle, incorrect White Balance Well, it's because your camera* isn't as smart as you thought it was. (*When I say camera, I am including phones, bridge cameras, digital SLRs and mirrorless cameras, for brevity.) If you want a quick fix to this problem, and don't care why, scroll down to the end. First, I am going to go into why this happens, which some people won't care about. Disclaimer This is not meant to be a detailed and accurate analysis of photography, colour balance, chromatography, or the psychology of colour perception. The solutions presented are basic and will suffice for the majority of photographs; they are not perfect. There are more advanced options that are out of scope. Why does this happen? I'm glad you asked. It's because your eyes are amazing. They do loads of things in the background that you don't notice. For example, they automatically correct for the colour of light. The light you get from an old-fashioned light bulb is very different from the light you get from an LED bulb, which is very different from the light you get from sunlight. And even sunlight varies depending on whether it has gone through clouds, reflected off the sea, etc. So, regardless of where you are, when you look at a gold coin, it looks lovely and golden. Even though the light might be really blue or really orange. Your eyes, and brain, just adjust and you don’t really know anything about it. Unfortunately, although your camera is very clever, and does lots of things in the background you don’t know about, it’s not that clever. In most ‘normal’ photos, like parties, holidays on the beach, pictures of mountains, the bright thing is the light source - the sky, or a light bulb on the ceiling. But when photographing a coin, the light source is hardly ever visible in the picture. If you show it a picture of a coin on a table, it only has that information. It does not know how it is lit. So it guesses. All it has to go on is a bright thing in the middle of a (usually) dark background. So it takes the bright thing as the reference, and assumes that is the colour of the light source. Then it adjusts the whole picture, so that the ‘light source’ is a neutral colour. How does it adjust the picture? Do you remember your colour wheel from school? Gold is orange/yellow, and blue is opposite that. So the camera makes everything in the picture more blue, in order to make the gold ‘light source’ more ‘white’. How do I stop it happening? The best option is to stop the camera ‘guessing’ what colour the light is, and tell it. You should be able to change a setting on your camera called “White Balance”. Move it from Auto to something approximating what you are using for light. There are usually options for daylight, cloudy, old bulbs, LED, etc. If there is a mixture, e.g. you are inside but near a window, then try Sunlight and then try LED, and see which is best. Keep trying different options until you find one that produces nice golden golds. There are more advanced ways of getting this exactly right, but those are beyond the scope of this tutorial. Oh, and don’t forget to put it back to Auto if you plan to take photographs of other things later. Otherwise, all your pictures of beaches and mountains will look terrible. How do I fix pictures that are already wrong? This is always going to be a bit of a compromise, but you can get good results with a tiny bit of effort. If you are using a phone, it probably has some basic ‘filters’ built into the camera app. Find one that reduces the blue. It might be called “Warming” or something like that. For cameras, there are lots of PC or Mac applications for basic editing of photos. Again, look for warming filters. If you have a slightly more advanced program, look for the ‘curves’ feature, select the blue channel, and drag it down to reduce the blue. Summary Silver sovereigns look ugly. Now you have no excuses. The same gold ¼ oz Eagle, corrected White Balance, aligned and cropped
  5. This guide is for people with an existing interchangeable lens camera and a lens with a focal length between about 30mm and 100mm. With a relatively low (£50 or less) investment, you can convert your existing lens to take macro photos. In comparison, a true macro lens will cost you £200 to £600. As I’ve stated in other guides, a 1:1 reproduction ratio is pretty much ideal for photographing coins. If your existing lens is outside of the 30-100mm range, you may struggle to get close to 1:1, but you can still use extension tubes to get much closer than you would without. What are extension tubes? An extension tube fits between the camera and lens; it has a camera mount at one end and a lens mount at the other. It looks like a lens, but is actually hollow and contains no glass. Using extension tubes effectively adds distance between your camera and lens, and due to the magic of optics (beyond the scope of this guide), increases the reproduction ratio (magnification). Which do I buy? You typically buy a kit of 2 or 3 tubes, and you can stack them to get combinations. Because there is no glass, you do not lose any image quality. Important: Make sure you buy the right tubes to fit your camera. Also, make sure you buy ones that are described as “auto focus”. They will pass the electrical signals from the camera to the lens. The price difference between sets is down to: Number of tubes in the kit: 1, 2 or 3. I recommend you get three, giving you most flexibility to experiment with magnification, and is the best value. Metal tubes are more expensive than plastic, but are a bit more resilient. This probably doesn’t matter for coin photography. Brand. There really isn’t anything to be gained from buying more expensive name-brand tubes, since there are no optics. What tube(s) to use with what lens? Below I describe the mathematical way to get to the desired magnification, and the experimental way. The maths You can skip this section if you want, and go to the experimental section below. Total reproduction ratio = Lens reproduction ratio + (Total tube length / Lens focal length) So you need to know the focal length of your lens (right in the name of the lens) and the reproduction ratio. The reproduction ratio is provided in the detail specification of the lens, and is easily Google-able. Example: Say you have a classic 50mm lens for your camera. Lens: AF-S NIKKOR 50mm f/1.8G Lens focal length: 50mm Lens reproduction ratio: 0.15 or about 1:7 (get this from the spec sheet) Tubes: 12mm, 20mm, 36mm Using a 36mm tube: 0.15 + 36/50 = 0.87 or about 1:1.2 That’s very close to the 1:1 ratio of a true macro lens. Using 12mm+36mm tubes: 0.15 + 48/50 = 1.11 or about 1:0.9 That’s slightly more than the 1:1 ratio. Experiment without the maths As a first guess, you want to use tubes with a total length of about ¾ that of your lens. So roughly: Lens focal length Attach these tubes 30mm 20mm 50mm 36mm 60mm 12+36mm 80mm 20+36mm 100mm 12+20+36mm After you look at the subject through the camera, if you need more magnification then add more tube length. If you need less, take it away. The longer your original lens, the more tube length you need to make a difference to your reproduction ratio. What if I use more tubes? Can I make a microscope? Sadly no. Every time you increase the tube length, you bring the focus distance closer. At some point, your focus distance will actually move to inside your lens, and you won’t be able to focus on anything. What about zoom lenses? What if your lens has a range of focal lengths, e.g. 24-70mm, i.e. a zoom lens. You can absolutely use extension tubes with zoom lenses. Zooming in and out will change the magnification ratio (see the maths above) and the possible focus distances. When experimenting enthusiastically, just be careful not to move too far forward and bump the lens into the subject! What are the drawbacks? Why do people ever spend money on dedicated macro lenses when you can just use extension tubes on existing lenses? As with everything, there are disadvantages. Most of these disadvantages get worse as the tube length increases. Maximum focus distance is reduced. When you use an extension tube, you will no longer be able to focus out to infinity. In fact, you probably won’t be able to focus beyond a couple of metres away. In order to use your camera for anything other than macro, you will have to take out the extension tube(s). You will lose some light. I won’t go into the reasoning or the maths for this, but the longer the tube length, the less light will reach the sensor. Since you are generally on a tripod and/or have control of the light, this shouldn’t matter. It’s a bit more cumbersome and lengthens the amount of ‘stuff’ hanging off the front of the camera. This is usually fine, as the tubes themselves weigh very little. Taken to extremes, if you used multiple sets of tubes, you might need a sturdier tripod. You are going to get very close to the subject. If you are using some kind of lighting rig, you may need to shorten the tube length. You are definitely going to need a tripod, to hold still for longer exposures. If you don’t want to use a tripod, shorten the tube length. The following aren’t exactly drawbacks, but there are advantages that dedicated macro lenses give you, specifically beneficial to macro photography, which you won’t get when using extension tubes with other lenses: Fine focusing. Most macro lenses allow very smooth adjustment of focus, for the tiny distances. Remember, you will almost certainly be manually focusing. Nice out-of-focus backgrounds (bokeh). Macro lenses generally have lots of diaphragm elements and curved elements, to smooth out the background. Smaller apertures. Most macro lenses can be set to very small apertures (above f/22), increasing the depth of field when needed. Alternatives to extension tubes There are other ways to adapt an existing lens to work as a macro lens. I am not going to give the full ins and outs, but I will list them here for completeness. I may write guides later, if there is interest. Reversing ring. The very cheapest (<£10) option. Believe it or not, it actually involves mounting your lens backwards, using a hollow metal ring that joins the front of your lens to the camera, instead of the back. Yes, it actually works. Macro conversion lens. This is like a reading glass for your camera. It screws onto the filter thread at the front of the lens, and varies the magnification of the lens in a similar way to tubes. Can be a bit more convenient, as it doesn’t significantly lengthen the lens. Also may be able to use on a fixed lens camera, if it allows attachment of filters. Bellows. These are effectively flexible extension tubes, where you can vary the distance between the lens and the camera precisely. Of course they are cumbersome, but they do give you a very cool retro-looking camera. Summary If you already have a camera with a medium(ish) lens, buy a set of three “auto focus” extension tubes and have a go at photographing coins close up. You should get some amazing results. I intend to do some experiments with different lenses, covering the top, middle and bottom of my suggested range of focal lengths.
  6. Looking to up your photography game by moving from a mobile phone to a 'real' camera? What makes a good camera for macro photography? This is the companion article to Choosing a camera macro lens. You should definitely read that as well. The lens is more important than the camera. For this article, I am not going to recommend specific models of camera. There are just too many and spoiler alert, most cameras will be fine. At the end, I do give a list of current models that will fit the bill for most people. What is macro photography? Macro, or ‘close up’ photography, is the technique of photographing ‘small’ things. The subject of a macro photograph is generally smaller than the sensor (or film frame) in the camera, i.e. about 24 mm or 1 inch high. As an example, a modern sensor has about 6,000 by 4,000 pixels. So each pixel is ‘seeing’ a spot of detail that is just 6x6 micrometres. Do I need a special camera for macro photography? No. Any modern interchangeable lens camera will work. So Digital SLR or Mirrorless. You need a macro lens to put on the front of it. What is an interchangeable lens camera? The camera (sometimes just referred to as ‘body’) comes without a lens by default. You can usually buy it in a kit form, with a very basic lens included. But if you are only intending to use it for macro photography, save your money and buy the body-only option. Remember to factor the price of a lens into your budget. You can’t use the camera without one. Of course, this does mean that you can buy more lenses for the same camera body, and build up a very flexible set of kit. What about fixed lens cameras (“bridge” cameras)? This is my opinion, but these days I wouldn’t buy a bridge camera. If you are looking to save money by not buying an interchangeable lens camera, use a recent model mobile phone instead. No shame, they can produce great results. The market for bridge cameras has all but vanished now, so I don’t think I am alone in this opinion. If you already have a fixed lens camera, look at the specifications to see if it is capable of taking close-up photographs, i.e. with a reproduction ratio of 1:1 or close. If so, you should be good to go. What factors should I consider when choosing a camera? There are a lot of cameras out there. Here are some things to consider. Age Camera models tend to cycle about every 3 to 5 years. You can save money by buying the previous generation. For the purposes of taking coin photos, it won’t make any real difference to the quality. What you gain with each generation is some more convenience features and maybe a little resolution (matters less than you might think). Most advances, year on year, will affect other types of photography much more than macro, e.g. video, frame rate, auto focus. I wouldn’t recommend going too old though. More than about 12 years, and you start to find cameras without some of the basic usability features we now take for granted, like live view (the ability to use the rear display to aim your shot). Brand I would recommend sticking with Nikon, Canon or Sony. Not just because they have excellent reputations, but because there is a huge ecosystem of lenses, accessories and support, especially for the first two. Sony is slightly newer to the game, but practically they are up there and have some excellent cameras. DSLR or mirrorless (If you don’t understand the difference, don’t worry about it too much.) These days, I’d say there isn’t much reason for sticking with Digital SLR. Again, it’s not an image quality thing, both will generate superb pictures. But Mirrorless cameras are generally slightly less bulky and are lighter than SLRs. The only real drawback is that Mirrorless cameras usually have worse battery life, but that’s probably not a big deal. Practically all the development for the last decade has gone into Mirrorless cameras. Full frame or crop sensor This refers to the size of the image sensor. Those a little older may remember 35mm film and APS film. Well, this is exactly equivalent in the digital world. A ‘full frame’ sensor is 35x24mm, and a ‘crop’ sensor is 25x17mm. Crop sensors are often called APS sensors. If you want ultimate image quality and most flexibility, go full frame. If you want to save money and have a smaller, lighter camera, go crop. Not only will the camera be cheaper, but there will be cheaper lenses available. The practical difference for macro photography is that you won’t be able to get as much in the image at minimum distance. For example, a sovereign is 22mm in diameter, which fits a full frame sensor perfectly, but doesn’t fit a crop sensor. All this means is that you will need to back away from the coin a few inches, to fit it in shot. Warning: If you choose a full frame sensor, you must choose a lens made for full frame cameras. Not crop lenses. This is not always obvious in the marketing, so do research. If you choose the wrong one, the lens will only produce a crop-sized image on the sensor, and all those lovely extra pixels at the edges of your sensor will be black or blurred. For example, with Nikon, FX on a lens means full frame, DX means crop only. Conversely, you can use a lens made for full frame cameras on a crop sensor camera. Headline camera features that matter less for macro There are some great recent advances in camera features. If you plan to use the camera for other things than taking macro shots of coins, some of these might be very useful. But for macro, not so much. Sensor resolution (megapixels). Unless you are planning on printing posters of your coins and hanging them on the wall, even the most modest digital camera will have plenty of pixels. Autofocus. You will be focusing manually, and your subject is stationary. Frame rate. Your subject is stationary. If you need a high frame rate to track your coin around the room, either something has gone very wrong or you are doing something well beyond the scope of this article. Low-light sensitivity. You should be using a tripod, so the exposure time can be long. That means the sensor will get plenty of light, enough to avoid image noise / grain. Viewfinder resolution. For wireless cameras, because they don’t have a mirror (like a SLR), the viewfinder is actually a small monitor. For macro photography, you will almost certainly be using the larger display on the back of the camera. Faster and bigger memory cards. Again, you aren’t taking shots at a high frame rate, and you are in the vicinity of the PC, so capacity is unlikely to be an issue. Other features that might matter Tethering might be a good option for you. This is when you have the camera connected (usually by cable, sometimes wirelessly) to your computer or other device. This gives you excellent control of camera settings, plus a better view of what the camera is seeing. And when you take a photo, it is on your PC or device immediately. No need to transfer it later. Older cameras may have limited functionality for tethering, or not support it at all. Resolution of the rear display. On older cameras (>12 years) the screens are pretty poor. For this task you don’t need to worry about brightness and viewing angle much, as you will probably be inside and directly behind the camera. But having a larger higher resolution screen would certainly be useful for framing and focusing. Focus peaking. This is a feature that uses the rear display to highlight the area of the image that is in focus. It is very useful when doing focus stacking manually, or just to confirm that what you want to be in focus, is in focus. Focus stacking. Taking multiple shots at different focus points, and merging them into one. Some cameras will do it automatically: you tell the camera how many shots, how much to change the focus between shots, and where to start. Press the button, and away it goes. What else am I going to need? Once you have the camera (body) and lens, you will need a memory card, a tripod and possibly some lights. Take a look at the Review of my gear to give you an idea of what is and isn’t important. In summary, choosing a camera If you are starting from scratch, my recommendation would be a cropped sensor mirrorless camera from Nikon, Canon or Sony. Examples that fit this description are below. These are not meant as specific recommendations, and are in no particular order. Do your own research, as everyone has different priorities. I have no personal experience of any of these models. Sony: A6100, A6400, A6600 Nikon: Z50 Canon: EOS R50, EOS R7, EOS R10
  7. 1980 Quin About 40 photos per stacked image, which is a lot. I was close to minimum focus, which means the coin was larger than the height of the frame. Therefore, I needed to do two passes, one for the bottom 2/3rds and one with the top 2/3rds. I think the large number of images caused some of the odd artefacts, like bloom and ghosting, visible in the final images. I will continue to experiment
  8. Looking to up your photography game by moving from a mobile phone to a 'real' camera? Or do you already have a camera, but need a macro lens to take close-up photographs of your coins? Let’s explain what a macro lens is and what to look for when choosing one for coin photography. I will go into a lot of detail, but I am assuming that if you are thinking of buying a macro lens for a camera, you are OK with that. Out of scope: I am not going to cover the type of macro lens that you clip onto a mobile phone, although many of the principles are the same. I am also not going to cover adapter lenses that you fit to the front of normal lenses to make them focus closer. What is a macro lens? A macro lens is configured so that it can focus on things very close. Macro lenses have the same ‘magnification’ as normal lenses, e.g. a 100mm macro lens will be the same amount of ‘zoomed in’ as a 100mm non-macro lens. The difference is that the macro lens will be able to focus on something about 20cm away, whereas the non-macro lens will need to be much further away, probably metres. Things to look for In decreasing order of importance, these are factors or specifications you should look for when choosing a macro lens. The first ones are highly relevant to making a good macro lens, and some things that are less so. Reproduction ratio The most important statistic. Most ‘proper’ macro lenses will allow you to get close enough to a subject that the image of that subject projected through the lens and onto the camera’s sensor is the same size as the subject. This is called a reproduction ratio of 1:1. For example, with a 1:1 lens a 22mm sovereign, at closest distance, will appear as 22mm on the sensor. Since a full-frame camera sensor is just 24x36mm, that's a perfect fit and a big image when viewed on a monitor. To make the image smaller, you just move away from the subject. But you can’t make it bigger, because moving closer would move within the minimum distance the lens will focus. With lenses that have a lower ratio, e.g. 1:2, it just means they can’t focus as close to the subject, making the resultant image smaller and the photography more cumbersome. You definitely would not want to use a 150mm lens with a 1:3 ratio, as you would need to be over a metre away from the coin. Some manufacturers still call these ‘macro lenses’ despite not reaching 1:1 ratio. At the other end of the scale, there are specialist ‘super macro’ lenses that have a ratio of 2:1 or even higher. They achieve this by allowing an even closer minimum distance. These are probably not to be recommended to anyone other than professional photographers, as they come with their own set of limitations and peculiarities. Considering that, to take a photo of a 1oz coin, you will already need to be further away than minimum distance for a 1:1 lens just to fit it on the sensor, going even higher is just unnecessary. Sharpness Obviously you want a lens that is sharp. This is especially true for macro photography, where you are attempting to reproduce tiny details. It is also especially true if your camera’s sensor has a lot of pixels, say more than about 10 million. Sharpness is a factor of the design and build quality of the lens. This is very much a “get what you pay for” factor. There is information online where sharpness has been scientifically measured. You can also read reviews that will tell you if a lens is sharp, and at what aperture it is sharpest. Typically, the optimum aperture is around twice the widest aperture. Focal length As the lens gets longer, the minimum distance extends. So a longer focal length does not lead to a large image - what you gain in ‘zoom’ you lose in distance. The main consideration here is convenience. If you have a longer macro lens, e.g. 150mm, your distance to the coin will need to be about 30cm or more. That can start to get awkward if you want to photograph downwards onto a table or desk. However, the focal length will probably not make a significant difference to the appearance of coin photographs. Just the convenience of taking them. Longer focal length macro lenses, >100mm, are useful for nature photography, where you don’t want to get too close to the subject because it might fly away (or attack you). This is unlikely to be a concern with coins. But you can go too short. Macro lenses <60mm are light and cheaper, but you start to have other practical problems. You need to be so close to the subject that you can block the light, and you may not be able to use axial lighting because there isn't room. Personally, I think the sweet spot for coin photography would be 60-100mm. If you are going to use the lens for something other than macro photography, then obviously the focal length may factor more into your decision. Shorter lenses will be better for street, architecture and landscapes. Longer lenses for sport, wildlife and portrait. If all other things are equal, typically the longer the lens, the more expensive it is. Smallest aperture Lenses often have an aperture that will go down to f/20 or f/24. Macro lenses often will go to f/32 or more. This increases the depth of field, keeping more things in focus. The issue though is that when you go beyond about f/16, you will begin to get noticeable softening of the image because the laws of physics take over and diffraction happens. Diaphragm The element inside the lens that varies the aperture to let more or less light through, is called the diaphragm. The number of leaves in the diaphragm can be relevant. If the diaphragm has a large number of leaves or elements (say above 8), the hole it makes will be more circular. This leads to smoother out-of-focus backgrounds (and foregrounds) called bokeh. It’s a subjective thing that sometimes matters, but is largely irrelevant for coins. Image stabilisation A very useful feature in any lens, to reduce handheld blur. But for a setup that will spend its life clamped down on a tripod, it is irrelevant. Of course, if you might use your lens for other things, it could be very handy. Auto-focus An area where some of the biggest advances in both lenses and cameras have been made over the last decade or so, is in the speed and accuracy of auto-focus systems. Fortunately for us, it doesn’t matter, because we will be manually focusing with macro photography, with the possible exception of an automatic focus-stacking process. Either way, the speed and accuracy of auto-focus is irrelevant. In fact some macro lenses are manual focus only, in order to reduce cost and give a very smooth feel to the focusing ring, for fine adjustments. Consider that your depth of field is often less than 1mm. That is not something a camera’s auto-focus system can reliably handle. Widest aperture The main factor that determines how much a lens costs, is its widest aperture. People spend a lot of money getting very wide aperture lenses, with f/1.2 or greater. Fortunately for us, this is almost completely irrelevant, since we will be taking macro photos with a fairly narrow aperture probably between f/8 and f/16. Zoom (variable focal length) Most lenses for general-purpose use are ‘zoom lenses’. They allow you to zoom in and out of a subject. A typical example would be a 24-70mm lens. The ability to zoom is not useful for macro photography, since as discussed earlier, increasing the focal length simply increases the minimum distance, so the net effect would be the same. It also adds cost to the lens and reduces the quality (e.g. sharpness). A true macro lens will normally be a fixed focal length, or ‘prime’, lens. How much to spend? The lens is more important than the camera body. This is something that people who are not familiar with interchangeable-lens cameras may not be used to. Put it another way. A camera body will last you somewhere between 3 and 10 years. The more features and technology you want, and the more you use it, the shorter its lifespan. A lens can easily last 20+ years, if you don’t abuse it. Where do you think your money should go? Personal experience: I have owned and replaced 4 camera bodies in 18 years. I am still using the first lenses I ever bought, never replacing any. Lenses are physical, mechanical things. Their quality is determined by optics and the craftsmanship that went into them. Sure, new features occasionally pop up, like image stabilisation and faster auto-focus. But the basic operation of a lens hardly changes between generations. That is definitely not true for camera bodies, which are basically akin to computers or mobile phones; electronics that constantly evolve. First-party lenses will cost you a lot more. For example, Canon lenses for Canon cameras. Nikon lenses for Nikon cameras. Third-party lenses, e.g. Sigma, Tamron and Tokina, are much better bang-for-the-buck, and are usually close to if not identical in quality. Rule of thumb. If you are starting out buying a camera and lens, consider the total price. If you are just buying one lens, spend ⅓ to ½ of your budget on the lens. If you are buying 2 lenses, then spend at least ½ of your budget on lenses.
  9. Hi This topic was inspired by comments from @theman73 and @Silverlocks. To summarise: trying to use a close-focusing telephoto lens to photograph coins. I have no idea how much you know about photography, so I will try to stay fairly basic. Some of what I say will not be 100% correct, as I may miss out scenarios and exceptions to rules. I welcome people correcting / augmenting my description in the comments. This topic is not meant to be a general tutorial on how to take photos of coins. Definitions (Feel free to skip if you are familiar with the terms.) Basically, aperture is how wide open the lens is. It is controlled by a diaphragm inside the lens that blocks the light. Sometimes this is fixed (most mobile phones), but sometimes it can vary. Confusingly, the wider the aperture, the smaller the f-stop number. f/1 is wide and lets in a lot of light, f32 is narrow and lets in a tiny amount of light. Put simply, depth of field is how much of a scene is in focus. A wide depth of field means both close and distant things are in focus. This is what most 'snappy' cameras and mobile phones want to achieve most of the time, because it's easy - when photographing groups of people, buildings and landscapes, you want everything in focus. A narrow depth of field means only a small 'range of distances' is in focus. This is useful for isolating subjects, like in portrait photography. Optically, depth of field is relative to the f-stop when the photo is taken, and that is determined by the ratio of aperture diameter (how wide open the lens is) to focal length (how long the lens is). The problem Mobile phone cameras have a relatively small diameter and therefore aperture. Normally, because the focal length is also pretty small, this leads to a kind of average f-stop of f/5.6 to f/11. This is a really useful range of apertures, and means that for most photography, most subjects are in focus and most backgrounds are pleasantly blurred. However, strapping a great big telephoto lens on the front means a small aperture coupled with a long focal length, which gives you a very small (high number) f-stop, say f/22 to f/32. So, you are not getting much light onto the sensor. To compensate for that, the phone will either decrease the shutter speed or increase the ISO (sensitivity), or both. Decreasing shutter speed leads to camera shake and motion blur, unless you are using a tripod. Increasing ISO leads to noisy photos and loss of detail. Also, having such a small f-stop has its own problems, as your lens starts to act as a diffraction grating, and you get blur. With such a small aperture, you would think that your depth of field would be pretty good. However, at macro sizes, your depth of field will still, at best, be a couple of millimetres. And that is only if you can get the phone to accurately focus with a third-party lens strapped to it. Put simply, there is no way a phone with a telephoto lens is going to match even the cheapest DSLR or Mirrorless camera with a macro lens. Physics just gets in the way at every turn. A lens and sensor that is 3mm across vs a lens that's ~60mm and sensor that's 35mm - no competition. What I would do Honestly, if your phone has a half decent camera on it with a high enough pixel count and good macro focusing (ultrasonic), take the lens off, hold the camera about 6-12 inches away from the coin, and take a photo. Even better, use a tripod, use manual settings to control the shutter speed and ISO, and that should sort out the camera shake issue too. Your coin will look tiny in the photo, but then crop it down - you have the megapixels to do it. How could it work? If you are thinking of buying a macro or close-focus lens for your phone, think long and hard. If you must, buy one from an established lens manufacturer, not a cheap plastic thing from Amazon. Optical quality makes a difference, and the example photos on Amazon are almost certainly fake. With or without a third-party lens, here are some tips: Use a modern phone. Something at the top of the range from the last 5 years or from a mid-range in the last 2 years. You need a high pixel count if you want to crop photos, and you need reliable focusing. Use a tripod. You can get pretty cheap mobile phone tripods. Get a metal one, not plastic, from a good tripod make. Plastic ones will be useless, and a waste of money. Use manual photo mode on the phone. Keep the shutter speed above 200 for hand-held. Let the ISO go wild - see post-processing. Take lots of photos and see what works - digital photos are free. Control the lighting. Precious metals reflect everything. If you can, build or buy a lightbox - a box about 1-2 feet on every side, with one side open for you, and drape some black cloth over the front to avoid light coming in. Use a flash or torch or some kind of light you can position. Lighting is a huge topic on its own. Learn how to do basic post-processing of photos. Find software that will remove noise from high ISO photos, and can crop and straighten images. I recommend G.I.M.P. which is free and has a lot of open-source community support.
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