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 Replies: 35 / Views: 7,361 |
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Pillar of the Community
 United States
4038 Posts |
Quote:
You are *such* an engineer Thank you kindly! I have a lustrous 1883-CC MS65 that will make a good vehicle for some lighting experiments. Sounds like a project for the weekend...Ray |
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Pillar of the Community
 United States
627 Posts |
Hi Ray, Here are the full sensor images of the axial shot of the Grant Medal. I resized them to 900 pixels wide, and everything else is exactly from the camera. Is this what you expected to see?   |
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Pillar of the Community
United States
627 Posts |
Here is another set of pictures for comparison. This is a 1907 Proof Liberty nickel, graded PF66 by NGC. Proofs are appreciably different when imaged with axial lighting versus direct lighting. The axial image was gamma adjusted 0.75 and brightened 20, then cropped and resized. The direct lighting image was cropped and resized only. No other post-processing was performed.
Axial Lighting: Direct Lighting: |
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Pillar of the Community
United States
4038 Posts |
No, not what I was expecting. If the light is axial, why is there no reflection off the surface of the slab? ...Ray
Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Pillar of the Community
United States
627 Posts |
I'm not sure?
The Ott lights are completely diffused, and the exposure is more than 1 second long. The particular angle of the glass is that which lights the coin most, and when I am adjusting the angle there is a clear swath of light across the front of the slab (not visible in the full image, because the swath of light is wider than the medal diameter). The only light that could be getting to the coin is that reflected off of the glass and down onto the coin.
I will continue playing, but my guess is that the high diffusion of the light sources dampen the perception of glare. The "glare" is a large swath of light across the entire frame of view, and thus the exposure avoids any burnt-out spots, and the loss of contrast and overall "graying" is the glare?
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Pillar of the Community
United States
4038 Posts |
I need to get a piece of glass out of storage tomorrow to set up axial lighting but I thought I'd start on a couple other techniques first. I tried my "final" setup, as well as the "down-reflector" setup documented in the "Coin Photo Setup" thread. Subject is a MS65 1883-CC that is toning in the holder (was blast white when I bought it in 1989, I hear this is common of old ANACS slabs). I had to change over to a Nikon 105mm lens as my PB-4 is unfortunately a bit too long to image a Dollar with the 75ARD1. Anyway, here are the images: "Final" Setup  "Down-Reflector" Setup  I'll try to publish axial Sat night...Ray Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Pillar of the Community
United States
627 Posts |
I have got to make me some of those smile diffusers this weekend.  Beautiful shots Ray! |
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Rest in Peace
United States
9104 Posts |
I like the down reflector image better, and the second proof nickel.
Now if people would quit seeing how big they can make images, we could see them side by side.
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Moderator
United States
23522 Posts |
 I never expected the "Down Reflector" setup to provide results like that. It's staggering. That's as close to "perfect" (for my sensibilities) as I've ever seen a Morgan shot. I gotta go back and see how you built that. Which thread was it in? VAM-5, by the way. You may or may not see some fascinating die polish lines to the (viewer's) left of the wing. |
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Pillar of the Community
United States
4038 Posts |
SuperDave...is that you in the pic? Photoshopped, I hope. I documented the down-reflector in the Coin Photo Setup thread. I also pictured a version in a couple other threads. Here's a link: https://goccf.com/t/87392&whichpage=7The one shown is simply white paper. But the one I used for the Morgan photo is cardboard covered with aluminum foil. The white paper version acts as a diffuser and you get very little luster, while aluminum foil version acts as a reflector and luster is supported. The extra distance helps the Jansjos look "bigger" and eliminates any pinpoint source issues, so they have not extra diffusion. I'm actually surprised at how nice it came out, having only tried it on small coins before. Maybe I'll give it a try on some Cents again and see if I can get a better result than the Smile Directors. Thanks for the attribution of VAM-5, I had not attributed it before and don't have a VAM reference. Is the info for attribution available online? Or do I need to buy a book? ...Ray Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Moderator
United States
23522 Posts |
Quote:
Is the info for attribution available online? Or do I need to buy a book?
http://www.vamworld.com/1883-CC+VAMsYou've really got to enjoy datamining to have success at VAMworld, though. And no, that's not me. |
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Pillar of the Community
United States
4038 Posts |
Thanks! Yep, it's a VAM-5 all right. Good info...Ray
Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Moderator
United States
23522 Posts |
I am fighting a running battle with chroma- and luminance noise with the 550D. It begins to seem like Canon is pushing the envelope a little too hard with 18MP on an APS-C sensor. Throwing more wattage at the problem helps - much reduced with halogens vs. the Jansjos - so I begin to wonder if the Jansjos are the solution for me. Question, Ray - has anyone ever codified the actual resolution of the 75ARD in LP/mm or some other unit? I've ordered a pair of Xenon bulbs for my track goosenecks, and a ring light, from Amazon to see what sort of effect I get. The Xenons run cooler than the halogens for the same wattage, and may help with the near-welding temperatures I face. |
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Pillar of the Community
United States
4038 Posts |
Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Moderator
United States
23522 Posts |
Holy Cow. That's just silly.
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Replies: 35 / Views: 7,361 |
First Page
Posted 02/03/2012 7:02 pm
