Susan - What's Your Secret?

The camera is an Olympus C-750 Ultra Zoom. Bobby had already done most of the experimentation with the light and such. The camera has a macro setting that I use for individual coins. This is the most important setting for getting clear close-up pics of coins. I am constantly moving the lighting around depending upon the coin. Most of my pictures are not quite as good as Bobby's were, but some have been better. I'm still learning.

For large group pics, I use the scanner, unless the coins are uncirculated. I always use the camera for coins with luster because the scanner doesn't show it well.

If you search all unarchived topics in the Coin Photography section for user bobby131313, you will get more helpful info. Bobby who is actually the one who knows the answer to your question. He went through a lot of trial and error to get the setup right.

Sorry, SuperDave. You, too, have beautiful photos!. Sharing secrets?

I have a Canon Powershot S1 IS. This is the 1st generation with 3 megapixels, 10X zoom & image stabilization - but no macro settings. So I'm trying to compensate & get some good ideas on how to.

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No problem. In all honesty, although I think I have Bobby covered with copper, gold and worn silver, he's still my daddy with lustrous silver and proofs.

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Actually Bobby hasn't taken a picture for about 6 months or more. They are all mine now.

Unfortunately, I'm terrible at explaining any of this process. Dave, you do have gorgeous pics. I'm glad that you were able to explain your procedure.

The trouble with keeping the coin on edge is that it's darn tough to keep it straight up. It won't stay. Now, a little tilt won't completely kill your chances of getting a nice picture. However, you'll find that the depth of field you get with wider (lower numerically) apertures won't be enough to keep the whole coin in focus if it's slightly tilted away from the camera. Your camera is, I think, capable of no tighter than f/8.0 - the highest-possible numerical aperture setting, and therefore the one which will give the greatest depth of field. This is problematic with a coin that's tilted away from the camera. I'm not sure that f/8.0 will be enough. If you find that you're not able to get the whole coin in focus at one time, the aperture setting is the culprit and the only way out is to get the coin more square to the camera.

I regularly find myself in the f/16-18 range, especially when shooting stuff on a slight tilt, and I've been as high as f/24. For the record, I'm using a Canon 350D with a Canon 100mm f/2.8 Macro lens, an incredible piece of glass which is capable of easily hiding my failings as a photographer.

A fellow poster over at the ebay Coins and Currency Forum has this neat little rubber-tipped clamp with small tips; with it he's able to tilt and move the coin into all kinds of odd angles. That might be something to look into. Have a look at thebleeper's pics in this thread:

http://forums.ebay.com/db1/thread.j...179408778976

And, Susan, I apologise if I've characterized your photographic work to have been Bobby's doing. I remember the days, months back, when he was grumbling about getting the photo setup right, and that's what led me to telling it that way. I remember the light-panel setup he described; you are getting such excellent results with it, on coins that give me fits, that I'm going to have to implement something like it down the road.

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What do you think?

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I think it's an excellent start, but hard to figure because of the rough life the coin itself has had.

Your light was at about 10:00 to the coin, and a little lower than it might have been for optimal quality. That's why the bright spots appear in the front of the profile, while the rear of the head has just a little too much shadow. So here's Lesson #2, understanding that your first pics are a really good start, good enough to just "tweak" a little bit:

For every step you tighten the aperture (higher number), if you lengthen the exposure one step (lower number, of course), you should end up with about the same shot. Aperture settings actually affect the diameter of the "hole" opened into the camera; tighter apertures mean smaller "holes", and therefore less light, but if you give the light more time to get in (slower exposures), you'll understand how the end result will be similar. The only other thing affecting the quality of your shot in this sequence if the quality of the lens (what I refer to as "glass); some lenses have settings at which they give clearer results than others. In the case of your S1, I will assume that the quality of the glass plays no role over the range of your settings - I have an S2, and it has glass of such quality that I can't see the difference anywheres in its' range of settings.

Now, the ISO setting is a far larger change. It quantifies the sensitivity of the sensor inside the camera to light, and the difference between ISO 100/200, or 200/400, is a lot greater than one step of aperture or exposure. Using your coin as an example, if you switched to ISO 400, you'd probably have to use an exposure of at least 1/250, maybe faster, to get the same result. ISO 400 and 1/160 would wash the coin out to the point where you couldn't see details. Thought of another way, you could probably hold to 1/160, and at ISO 400 you could set the aperture all the way up to f/8.0 to get the same shot.

It is our goal to keep the exposure as short as possible, which allows for the sharpest possible focus, and the aperture as tight as possible, which allows the greatest depth of field. Both of these factors are critical in coin photography. We're not taking closeups of flowers here, we're shooting coins for evaluation by collectors, and we need every single detail as sharp as humanly possible. The two parameters I'm talking about here, focus and depth of field, are critical in coin photography. You have to absolutely maximize their quality, to a greater degree than almost any other type of photographic subject.

So, you might conclude that the highest-possible ISO is the solution, because it allows you the tightest aperture and shortest exposure for a given amount of light. Unfortunately, it ain't that easy. The tradeoff of higher ISO settings is noise - you begin seeing graininess in your shots at ISO 400 that wouldn't have been there at ISO 200. Luckily for us, macro photography of coins tends to minimize graininess, especially when you're using a lot of light. It's less a factor to us, here, than it would be to someone shooting pics of the family pet sitting in the living room, for instance.

It's very likely that ISO 400, the highest setting available to your S1, will not compromise the quality of your pictures.

Here's my suggestions for your next steps. You're using the maximum image quality settings, right? Image Quality sets at Superfine, and Image Size to Large. I would recommend that you use a larger coin than a dime for the learning process - at least a Quarter and preferably a Half. That will make your image large enough for you to clearly see the differences in detail that changes in settings will make. Use a coin that's a little worn - great luster makes the correct lighting much more difficult, and I'd rather you became comfortable with the manual settings of the camera before we start playing with light.

OK. For your next set of shots, use the same light in the same place. Set ISO to 400, aperture at f/8.0, and use the same 1/160 exposure. I don't know how bright the resulting shot will be - my guess is it'll be roughly the same. Don't worry about the light yet, or the fact that the front will be bright while the rear will be dim - concentrate on finding the sharpest image you can get.

If you find the coin to be really washed out, too bright, run the exposure up to 1/200 or better, to the point where the coin is just a little too dark for your taste. Save that shot, and write the settings for that one in your notebook. Then take a group of shots, using one step slower exposure for each shot, and recording the setting for each. My guess is you'll get a range of about 4 shots that you'll find more or less acceptable.

Then bring the aperture one step wider, to f/6.5 or whatever the next setting is, and repeat the process. If you started at 1/200 at f/8.0, you'll probably start at 1/160 at the new aperture. Don't be too picky about details, just take the shot, record the setting, and go through the range of settings that give you something reasonably acceptable.

Repeat this process all the way down to the widest aperture setting your camera has. Once you're done, it's time to open each and every single picture in whatever display software you have, and check the results. Make each picture as large as you can on the screen, up to the actual size of the image. Don't magnify it to bigger than the camera made it. At your camera's best setting, your pics will very likely be bigger than your screen can display - I want you to see the whole coin right now, not just a piece of it, because you're going to be looking for the half-dozen images you like the best of the whole bunch.

As you come across one you like, move it somewhere else. Once you get through the whole batch, take a second trip through the ones you moved, eliminating all but the best 4. You might find that you have more than 4 which are good enough.

This is going to be a whole lot of pictures. I have three reasons for recommending this process. First, it'll give you the chance to find out where your particular camera and glass are the happiest. My camera/lens is happiest around f/12-f/18; yours, of course, will be something entirely different. Second, it will make you comfortable with playing with your camera's manual settings - the goal is to make changing these settings a subconscious process which you don't have to waste much time thinking about. Third, it will give you a lot of practice actually studying coin images, and refine your judgment as to what makes for a nice coin picture.

OK. Now you're down to 4 pictures. It's time to go through them at a little magnification. You want to see which is the very sharpest of them, and looking at them with larger than normal magnification will help you see the differences in sharpness. You may end up with one that you prefer over the others; you may not. Ideally, I'd like to believe that you'll end up with one superior shot at each aperture setting - that will tell you that you've got a really good camera. If not, it will tell you what settings your camera is happiest at. These settings will be pretty consistent across all types of coins - once you figure this out, you will only be varying aperture by maybe one stop each way, and exposure by maybe two or three steps each way. You will be going down to ISO 200 for the very brightest coins, but the exposure and aperture won't be changing much.

Are you seeing where I'm going with this? I understand, it is a lot of work. That's how you become a good coin photographer. It's the only way. I have taken thousands of shots over the last few years to get where I am. I currently have on my hard drive 4,000 coin images, totaling over 3 Gigabytes, and those are only the ones I liked well enough to keep. Maybe 20% of the total.

I will not tell you to compromise or shorten this process, but it may be that you will be able to reach the goal of learning your camera, and your personal skill, more quickly. That is up to you.

Another question for SuperDave, or anyone can chime in:

In addition to the suggested settings above, what about photographing slabs? What changes should I make?

Not sure if this was mentioned yet, but DON'T SCAN SUSANs. They will turn up like dirt in the photo.

I get the best results with my digital camera.
1. I turn off the flash
2. I move the lense close to the coin standing strait up (DON'T ZOOM. It'll blur the image)
3. Turn on the macro setting (Flower Icon)
4. Take the photo and keep the camera 100% still, because no flash makes most digital cameras more suseptible to blurry movement.
5. Download into a photo editor and apply a blue color filter to balance the lighting enough to give the coin photo the same color as the actualy coin.

SuperDave you know a lot of things about photography.

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However, you'll find that the depth of field you get with wider (lower numerically) apertures won't be enough to keep the whole coin in focus if it's slightly tilted away from the camera.

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I do not agree with you here. Depth of field is a problem with your DSLR which has a much larger sensor. With the Ef 100mm2.8 you get half a milimeter depth of field at f/2.8 and 30 cm distance from the subject. With an S2, in the same conditions (16mm, f/2.8, 30cm distance) you get a DOF of 1 cm.
So as a general rule, the depth of field of a 1.6x DSLR is 20 times shallower than the DOF of a compact 1/2.5".
The S2 and most compact cameras work at 36mm equivalent with the macro function and with 0-10 cm distance from the subject.So:
36mm equiv, f/2.8, 10 cm distance: 0.8cm depth of field
36mm equiv, f/4, 5cm distance: 3mm depth of field.
With your Ef , at 100mm, 30cm distance, you need at least f/12 to get the same depth of field.
These are "extreme" conditions since going closer than 5 cm will usually result in a great loss of the available light.

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I regularly find myself in the f/16-18 range, especially when shooting stuff on a slight tilt, and I've been as high as f/24.

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At f/18, 100mm, 30cm distance, you get 0.4cm depth of field, so about the same as an S2 would get at f/2.8

So, using a compact digital camera, high apertures (small f numbers) shouldn't produce missfocuses due to insufficent field of view.Tilting a 3cm coin with 10-20 degrees is free of negative effects. And anyway, tilting a coin more than that would produce lens distortion effect, which is much more visible for small lenses and almost imperceptible with your mammoth.

One more thing I'd like to say is that, in my opinion, for compact cameras is highly advisable tu use large aperture, due to the diffraction limit phenomenon.
With your 350D, diffraction starts at about f/16. With a usual compact, it generally starts at abou f/4. The S3 IS is diffraction limited at aboutf/3.2, and most new-generation-many-megapixel cameras are diffraction limited at any apperture. Diffraction is a phenomenon caused by the fact that in a compact digital, pixels are much smaller than in a DSLR. This phenomenon affects details and usually is perceptible in areas with thin lines close to each other, like on the reverse of a 1865 2 cents.