Numismatic and History Discussions > Coin Photography, Conservation and Storage

Photographing scyphate (cupped) coins - Methods and setups

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Anaximander:
I typically use a 16mm extension tube on my macro lens, an Olympus 60mm Micro four-thirds. The lens itself is equivalent to 120mm in the traditional 35mm camera world.  I am uncertain of my effective lens size with the extension tube, but I find it gives me more working room.

In fact, it should be possible to stack two or more extension tubes, one atop the other.

Instead of buying a new lens, couldn’t Jay use a set of inexpensive extension tubes. Optically, since there isn’t any glass in an extension tube, there isn’t any distortion, and image quality does not suffer, right?

Ron C2:
Extension tubes usually increase magnification, so you can fill more of the frame with the coin, but they don't usually change the focal length to the focal plane and often you get less working distance, not more, but with greater magnification. To get more working distance, a teleconverter can sometimes be paired with a macro lens, or you can try an extension tube on a telephoto lens, some lenses perform well as quasi-macro lenses this way.

In essence, the extension tube increases the distance between the lens and the sensor. you can then focus closer to increase magnification. The longer the focal length of the lens you pair with the tube, the greater the working distance you can achieve.

In terms of image quality, the extension tubes can introduce vignetting and can lower image quality for some lenses, depending on the lens element group design. I usually have to try it to know which lenses will have detectable image quality reduction.

There is a good primer here: https://shuttermuse.com/ultimate-guide-to-extension-tubes/#how

FWIW, you should not need an extender with a M43 60mm olympus lens.  I use the 50mm 4/3 version of that lens with an M43 adaptor and I don't need tubes to get good working distance and sharp images.

Virgil H:
I am going to throw one more option here that has been my best bet so far as I do not have a macro lens. And it is an inexpensive solution if you already have a camera with a lens that has screws for filters. It is a "macro attachment" that screws into the front of the lens and basically acts like a magnifying glass. Downside is you have to get pretty close to the coin to get an in-focus shot that fills the frame. I have the camera on a tripod for stability, so you need a tripod that will tilt the camera true 90 degrees without obstructing the view. If you look at the last few photos I have posted (one yesterday in Greek section), my results are acceptable, but I need to work on lighting. These are my best coin pictures so far using just what I already have. The phone camera does not work for me, but I have a crappy and cheap phone. These macro extensions have glass, and are pretty thin, they are not extension tubes. They are very inexpensive, you just have to make sure you get the correct thread size for your lens. I have used it handheld, but shaky hands is a real issue, hence the tripod or stand.

Regards,
Virgil

Ron C2:
Virgil, I can't say I've used a macro converter lens to photograph scyphates, but the few times I tried them in the film era, they usually did not produce great depth of field at magnification. That said, technology constantly improves and the new stuff might be decent.

Have you had good results with scyphates and these adaptors? Any examples to share?

Virgil H:
Ron C2,

I did an example of a photo with the macro attachment. This is my only cupped coin, a BI Trachy of Alexius I Commenus. I spent a little time working on this, but the huge caveat here is i know my lighting is horrible. That said, ignoring how bad my lighting is, for this coin, the macro attachment seems to capture detail pretty well. I think this may be an option for those with older cameras and no macro lens. You can get these optical attachments for around $10 these days. I attached a photo of the attachment. I have an inexpensive and rather old Epson EOS camera. And I know my lighting is my biggest issue.

Regards,
Virgil

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