Author Topic: Cameras for coin photos  (Read 24152 times)

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Offline badon

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Re: Cameras for coin photos
« Reply #15 on: August 14, 2010, 07:42:41 PM »
Looks like a good loupe can be put in front of a camera lense to get even closer to your subject for macro photography:

http://www.google.com/search?q=loupe%20macro
http://www.google.com/images?q=loupe%20macro
http://www.flickr.com/search/?w=all&q=loupe+macro

Most of the photos were taken with very poor quality loupes. Once I decide on the loupe I want to get (probably a Belomo), then I'll give it a go and see how it turns out. In the meantime, check out my posting about loupes:

http://china-mint.info/forum/index.php?topic=878.0

Offline badon

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Re: Cameras for coin photos
« Reply #16 on: September 21, 2010, 01:41:11 AM »
Here's the loupe photos:

http://china-mint.info/forum/index.php?topic=934.0

It didn't work out so well with auto focus. But, luckily, the Canon S95 and G12 are finally announced, according to the latest rumors:

http://www.canonrumors.com/forum/index.php/board,3.0.html

Offline ?

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Re: Cameras for coin photos
« Reply #17 on: September 21, 2010, 05:48:14 PM »
@qwasty: Do you have any expercience with USB mircoscopes likie this one?

http://cgi.ebay.de/Digital-USB-Farb-MIKROSKOP-200x-Bild-Video-USB-2-0-/370352269226?pt=LH_DefaultDomain_77&hash=item563ab727aa

Thanks

anwir

Offline badon

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Re: Cameras for coin photos
« Reply #18 on: September 21, 2010, 06:01:44 PM »
Yes, I looked at those too. I decided they weren't worth the trouble, but I never bought one. If I want to, I can use a Joby Gorillapod to hold the camera over the coin in macro mode, and record a video of if, and then output the video to a large display using the camera's built in HDMI output port. Here's the Gorillapod:

http://joby.com/gorillapod

There might be good reasons to want a USB microscope, but I decided the higher quality and versatility I get from a real camera was better for me. I decided I wouldn't bother with such a thing unless I were going to get a professional stereo microscope.

If all you want to do is get good quality images of your coins, I think a USB microscope would only be a good idea if you wanted something cheap. I don't know how well it will work though. For me, getting the good quality camera saved me money because it's the only thing I need.

Offline SANDAC

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Re: Cameras for coin photos
« Reply #19 on: March 14, 2014, 07:43:36 PM »
A forum member PM me about my camera setup.  I thought I re-post my respond here with additional notes and a picture of my setup.
 
My camera setup is an evolving series of trial-and-errors and small improvements. My old point-and-shoot died last year and I purchased my first DSLR last Christmas, a Nikon 5300.  A camera stand is a must (http://china-mint.info/forum/index.php?topic=7931.msg46723#msg46723) so is a CPL filter (http://china-mint.info/forum/index.php?topic=7632.msg44407#msg44407).  I find natural lighting with large window and indirect light is best for pleasant-looking coin pictures but diagnostic pictures require more harsh oblique lighting. I have a couple goose-neck spot lights, but I'm currently playing with LED ring light.  I can get closer and more consistent lighting with a LED ring light. A remote shutter and camera stand mean shutter speed is not important so I usually shoot ISO400 in aperature priority mode with a F/stop of 8 for reasonable compromise between depth of field and diffraction loss.

Macro lens is nice, but I've discovered something called "extension tube" that's very cheap and convert regular lens to macro lens.  I put it on my 300mm and use it to photograph bugs and bees and they came out great.  So a dedicated macro lens is not really necessary.  

It is still evolving, the thing I'm fighting now is specular reflection between mirror coin surface and clear plastic slab.  I still have a lot to learn about coin photography so feedbacks are appreciated.  

Offline SANDAC

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Re: Cameras for coin photos
« Reply #20 on: October 21, 2015, 12:59:06 PM »
I'm trying a photography technique to show the 3-D details of a coin.  It is called focus stacking where a well-focused image is synthesized from better focused portions of many images.  The medallion below is synthesized from 8 images focused on different points of the tilted medallion.  The image synthesis is done automatically in Photoshop which is kinda amazing.  Compare that to the single image focused on the chest of the astronaut (second image) one can see the image is well focused from edge to edge.  My question is whether this technique is useful.  Does the synthesized image have undesirable artifacts from the blending of different images?

Offline KeepOnTrying!

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Re: Cameras for coin photos
« Reply #21 on: October 21, 2015, 01:53:33 PM »
Can you do your alternating coin sequence magic so to allow closer comparison?
KeepOnTrying and Never Give Up!
That lion is also after you!

Offline SANDAC

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Re: Cameras for coin photos
« Reply #22 on: October 21, 2015, 02:37:49 PM »
Ah, an excellent suggestion.  Should've thought of that myself.  Unfortunately the combined image is too large (13meg), I have to reduce resolution by 40% to upload.  Yes, you can see some discrepancies due to the merging of multiple images.  Some of them are due to differences in brightness of individual images which means I'll need to go to full manual mode to make sure all images are uniformly exposed.

BTW, the medallion is 3 inches in diameter and weight over 1/2 pound.  It is propped up 1 inch on one side. 

Offline fwang2450

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Re: Cameras for coin photos
« Reply #23 on: October 21, 2015, 06:32:36 PM »
Reviving this topic is certainly interesting. I have been trying to get clear pictures in the past two years. Recently a QQ group was organized in China for numismatic photography, led by a professional photographer/collector.

Here is my latest attempt, with a newly acquired Nikon 50mm f/1.8 micro lens and a 20mm extension tube.

Offline SANDAC

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Re: Cameras for coin photos
« Reply #24 on: October 21, 2015, 08:34:08 PM »
Very nice!  That is a gilt goldfish, right?  The detail of the goldfish tail is not as brilliant as some of the brass goldfish pictures I've seen.  You have a number of hand-carved medals and I think it would be really informative to see comparison of the original/restrike/plated carefully photographed.

I'm new to DSLR and after fiddling around with different lens, tripods, and borrowed cameras,  I've came to the conclusion that the limiting component is not the modern multi-megapixel camera sensor but the lens.  The zoom lens is nice for walking around, but nothing gives you a sharp image like a primary lens.  The Nikon 50mm/f1.8 is an amazingly sharp lens.  That and a set of extension tubes will serve you very well for coin photography.  The downside is that you can no longer blame your camera for bad pictures!    :laugh:

Offline fwang2450

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Re: Cameras for coin photos
« Reply #25 on: October 21, 2015, 08:55:05 PM »
Very nice!  That is a gilt goldfish, right?  The detail of the goldfish tail is not as brilliant as some of the brass goldfish pictures I've seen.  You have a number of hand-carved medals and I think it would be really informative to see comparison of the original/restrike/plated carefully photographed.

I'm new to DSLR and after fiddling around with different lens, tripods, and borrowed cameras,  I've came to the conclusion that the limiting component is not the modern multi-megapixel camera sensor but the lens.  The zoom lens is nice for walking around, but nothing gives you a sharp image like a primary lens.  The Nikon 50mm/f1.8 is an amazingly sharp lens.  That and a set of extension tubes will serve you very well for coin photography.  The downside is that you can no longer blame your camera for bad pictures!    :laugh:

This is brass, not gilt :) I am kind of proud to be able to capture the "soul" of brass medals.

I made a mistake. The 50 mm f/1.8 lens is not macro/micro, but prime. But its sharpness is superb, better than my 105 mm micro.

I totally agree with you that it is the lens, and the way to use them, that is the key to good pictures. I have been fumbling around, till I got hold of this lens, which gives really sharp pictures.

There is an interesting discussion on the setup of coin photography here: http://boards.collectors-society.com/ubbthreads.php?ubb=showflat&Number=6693713

Offline PandaCollector

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Re: Cameras for coin photos
« Reply #26 on: October 21, 2015, 10:04:58 PM »
In order of importance for good coin photos I would vote for 1: lighting 2: lens 3: camera. Getting all three right leads to 4: photographer.

Best wishes,
Peter Anthony
China Pricepedia
www.pandacollector.com

Offline dynamike51

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Re: Cameras for coin photos
« Reply #27 on: October 22, 2015, 12:27:52 AM »
This is brass, not gilt :) I am kind of proud to be able to capture the "soul" of brass medals.

I made a mistake. The 50 mm f/1.8 lens is not macro/micro, but prime. But its sharpness is superb, better than my 105 mm micro.

I totally agree with you that it is the lens, and the way to use them, that is the key to good pictures. I have been fumbling around, till I got hold of this lens, which gives really sharp pictures.

There is an interesting discussion on the setup of coin photography here: http://boards.collectors-society.com/ubbthreads.php?ubb=showflat&Number=6693713

fwang and SANDAC,

If I may suggest that, as long as you're using a DSLR w/ 40mm (or 50mm) prime lens, you step up your aperture (a.k.a f-stop) to 18. Looking at your setup, you have sufficient light source to compensate for the small aperture. Doing so will allow your camera to capture the details beyond the focal point. Also, you can set your shutter speed to 1/60 since this is a still photo.

http://improvephotography.com/photography-basics/aperture-shutter-speed-and-iso/

Offline SANDAC

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Re: Cameras for coin photos
« Reply #28 on: October 22, 2015, 11:38:59 AM »
My camera is mounted on a copy stand, so the shutter speed can be lower to a second or more. Like you said, the depth of focus is directly related to f-stop so higher f-stop (or smaller aperture) gives greater depth of focus.  Unfortunately smaller aperture also introduces more diffraction blur.  I routinely use f/16 for flower photography because I want the flower petals soft rather than sharp, but for coins I want to see the scratches, blemish, and extra materials in tight corners.  Therefore I want to operate the lens in its optimal sharpness zone which is usually one aperture stop from its maximum aperture.  For my 40mm f/2.8, which has a variable max aperture at the closest distance, I like to keep the aperture between f/4 to f/5.6 for the sharpest detail. The sweet spot of fwang2450's 50mm f/1.8 is probably f/2.8.  At that aperture the depth of focus is so shallow that he'll need to make a decision about whether to focus on the mirrored fields or the frosted devices.  This is where focus stacking becomes helpful merging focused fields of one image with focused devices of the second image to form a composite sharp image of both fields and devices.  Alternatively he can raise f-stop to 5.6 and focus on the frosted devices and call it good.  It seems such a waste of an excellent lens, though.

Offline fwang2450

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Re: Cameras for coin photos
« Reply #29 on: October 22, 2015, 11:51:46 AM »
According to Ray, owner of this site: http://www.macrocoins.com/, f5.6 is optimal for pennies and dimes, and f6 is best for dollar sized coins. I have been using large apertures on my Nikon 105 mm micro, which yielded not-so-sharp pictures. I was advised by the professional photographer that large apertures result in less sharpness. I have yet to test other aperture settings on this lens. But f5.6 did give excellent sharpness on the f/1.8 lens, known for its clarity.

This is where people discuss coin photography: http://www.coincommunity.com/forum/forum.asp?FORUM_ID=81