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Pillar of the Community
United States
4132 Posts |
The obverse of this error is not flat, so I made my first swing at focus stacking. 3 shots at f/4.8 (obverse only, the reverse was fine with one shot at f/5.6).  2007-P Roosevelt dime Shattered Die by CaptainFwiffo, on FlickrThat worked well, so I thought get a little more ambitious and try it for closeups. 5 for the date and then 8 for "liberty" also at f/4.8.  1980 Lincoln Memorial cent DDO FS-101 (closeups) by CaptainFwiffo, on Flickr |
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Pillar of the Community
 United States
4038 Posts |
Captain...the shots look good, but may be a bit over-sharpened. When using CZP, It's best to have zero sharpening in the source images so the program has an easier time distinguishing in-focus and out of focus areas. Also, CZP does a fair amount of post-sharpening after stacking, so pre-sharpened source files will end up over-sharp if you're not careful. A lot of the stacked shots I've published are over-sharpened due to this, but I've been more careful with recent ones especially with the source files. Are these shots with the 75ARD1?
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Pillar of the Community
 United States
4132 Posts |
It's stupid flickr that's over-sharpening them when it makes the different sizes - I wish I could turn that off. I could make and upload different sizes myself (which would let me work around that stupid gamma bug), but it's not worth the effort and makes them hard to organize. Maybe I should use a different photo hosting service.
I turn off all sharpening during my raw processing, and usually find they don't need any sharpening after the fact. I think I only applied sharpening of any kind to the final version of the 1944-D I posted earlier to make the luster pop a bit, but only a touch.
They are all shot with the 75ARD1. I just used Photoshop to stack them and it seems like it did an acceptable job.
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Pillar of the Community
United States
4132 Posts |
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Pillar of the Community
United States
4132 Posts |
When focus stacking with the 75ARD1 do you recommend opening it up all the way or is it best to step it down a notch or two? It seems like most lenses aren't quite their best wide open...
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Pillar of the Community
United States
4038 Posts |
Focus stacking hides a multitude of sins. The long-CA is worse at f4, but if the stacker is working properly it won't pick up any of the off-color pixels since they aren't in focus. Field flatness is not as good at f4 but again stacking will completely compensate. I've done some very nice stacks with the 75ARD1 wide open and it is there that you will get the best resolution in a stacked image. That said, it's probably worth doing a stack at f4 and one at f5.6 to compare, but of course you will want to do fewer images at f5.6...
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Pillar of the Community
United States
4132 Posts |
Good point. I don't know what the sins of the 75ARD1 are when it's wide open. I guess stacking wouldn't help lateral CA or coma, but I don't think it has those particular problems.
I guess the answer is again to try different things and experiment.
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Pillar of the Community
United States
4132 Posts |
I've been playing around with focus stacking some more, not being satisfied with variety shots. 
1957-D Lincoln Wheat cent RPM Focus Stack by CaptainFwiffo, on FlickrThis is with the 75ARD1 at the maximum magnification I can get on my current setup. I ended up settling on f/5.6; I tried wider apertures, but they ended up softer or had artifacts. I think the lens has significant coma wide open at this magnification (at least, it looks like coma to me). Here's the "focus block" I built.  Lego Focus Stacking by CaptainFwiffo, on Flickr |
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Moderator
United States
23522 Posts |
OK, that focus block may be the coolest thing I've ever seen. Looks like you took a large pile of electrical panel grounding blocks, and a hit of acid.  |
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Pillar of the Community
United States
4132 Posts |
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Pillar of the Community
United States
4038 Posts |
Captain, you are a Lego master!
I have a comment on your 57-D pic...when taking pics of whole coins, lighting to emphasize luster is OK if that's the presentation you are looking for. But for variety details, significant diffusion usually gives a better result. I even resort to ring lights (gasp!) occasionally to get the best visibility of a variety. But other than the excess luster the shot looks excellent.
Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Moderator
United States
23522 Posts |
Quote:
It's 100% Lego. You are my hero. |
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Pillar of the Community
Australia
674 Posts |
 . Absolutely impressed not just with the tower but the mind that envisaged it.! I am going to show everyone I know at least twice.!!  |
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Pillar of the Community
United States
4132 Posts |
Lego Technic parts actually make it really simple to assemble a basic gear-train. There aren't any unusual parts or exotic construction techniques in there. This shot was really more of an artistic shot than a diagnostic one. I do have a ring-light, but I can't use it with the focus stacking rig unless I redesign it. It's held stable by being wedged between the frame of the bellows and the microscope platform. I need to build a low-profile version. I have tried the ring-light on proofs, although I haven't shot that many proofs; I'm not sure if I like it that much or not.  [/url] 2009-S Proof Lincoln Bicentennial Cent by CaptainFwiffo, on Flickr |
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Moderator
United States
23522 Posts |
That's a subjective thing; I consider what you've shot there to be the pinnacle of Proof photography. That's what a Proof should look like to me, which is why I'm such a fan of ring lighting for Proofs.
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Pillar of the Community
United States
4132 Posts |
Yeah, it's also really easy to set up. I would like the reverse effect though for comparison; light fields with darker devices, maybe via axial lighting.
I've mostly been photographing silver, but I'm wondering if I'm doing copper properly. After I white-balance them, they're a nice coppery orange, but really, that proof is a lot closer to coppery pink in-hand, and so is that '57-D. I didn't really notice at first, because it's still a subjectively nice color, but I don't think it's accurate.
I wonder if the if the combination of copper, plus the spectral characteristics of the LED lights and spectral sensitivities of my camera are fighting.
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Replies: 20 / Views: 4,307 |
Posted 08/04/2012 8:14 pm
