Scales of a Madacascar Sunset Moth (5x)

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fofx
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Scales of a Madacascar Sunset Moth (5x)

Post by fofx »

I received a beautiful moth as a Christmas gift. I'm blown away by the colors of the scales.

I'm also overwhelmed with how much retouching needs to be done. Most notably there are a lot of areas with a hazy glow from the really bright areas. It's especially noticeable where the bright and dark areas meet. I find that as I'm retouching with the original photos, the color difference is quite different, so as I'm retouching the glow off of a dark scale, the dark scale will be sharper with less glow, but the color is a much lighter shade than the stacked photo. Does anyone have some tips to speed up the touch up process or how to avoid these artifacts in the first place? I'm using Pmax with Zerene Stacker.

Image

Scarodactyl
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by Scarodactyl »

What optics are you using?

fofx
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by fofx »

Scarodactyl wrote:
Mon Dec 26, 2022 9:23 am
What optics are you using?
Mitutoyo 5x with a reversed TTL200.

rjlittlefield
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by rjlittlefield »

Scales like these are always troublesome. Bright highlights expand as they go out of focus, causing their out-of-focus blurs to intrude into nearby dark areas. Meanwhile the dark areas are very dark, with almost no visible detail, so in those areas the software has trouble figuring out what is real detail and should be retained, versus the edge of an OOF highlight that should be rejected. The problem is worse with directional lighting, because that causes the OOF blurs to have sharper borders that are easier to confuse for real detail.

For starters you should make friends with DMap. That's because DMap faithfully retains the color and contrast of the source images, while PMax tends to alter colors and increase contrast. In addition DMap settings can be adjusted so that DMap only looks at small scale detail, and there's a slider that gives you some manual control over bright halos in dark regions. For an image like this, with lots of fine detail where there is visible detail at all, I suggest to drop the DMap Settings > Estimation Radius to a small value like 3-5, versus its default 10. While you're doing that, the Smoothing Radius will automatically adjust to match. Then when you're running DMap, at the point where it pauses to adjust the contrast threshold slider, you can adjust the slider so as to eliminate bright blobs in the dark areas. There's a general tutorial about DMap on the Zerene Stacker website, "How To Use DMap". It does not specifically address the situation you have here, but it does explain some of how DMap works so hopefully that will help span the gap.

There are two more things it may help to know. First is that the default retouching brush paints details, not overall color and brightness. That's by design, to facilitate retouching with PMax. But for retouching DMap in this situation, I expect you'll be happier with the Pixels brush, which just copies pixel values like Photoshop's clone tool. Second is that the process called "slabbing" may help to reduce the effort of retouching. See https://zerenesystems.com/cms/stacker/docs/slabbing for more about that. The Pixels brush and slabbing are both "Pro-only" features, so if you're using Trial or Personal Edition, you'll get a warning about needing at least Prosumer Edition to continue using those features in the long term.

--Rik

fofx
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by fofx »

rjlittlefield wrote:
Mon Dec 26, 2022 11:08 am
Scales like these are always troublesome. Bright highlights expand as they go out of focus, causing their out-of-focus blurs to intrude into nearby dark areas. Meanwhile the dark areas are very dark, with almost no visible detail, so in those areas the software has trouble figuring out what is real detail and should be retained, versus the edge of an OOF highlight that should be rejected. The problem is worse with directional lighting, because that causes the OOF blurs to have sharper borders that are easier to confuse for real detail.

For starters you should make friends with DMap. That's because DMap faithfully retains the color and contrast of the source images, while PMax tends to alter colors and increase contrast. In addition DMap settings can be adjusted so that DMap only looks at small scale detail, and there's a slider that gives you some manual control over bright halos in dark regions. For an image like this, with lots of fine detail where there is visible detail at all, I suggest to drop the DMap Settings > Estimation Radius to a small value like 3-5, versus its default 10. While you're doing that, the Smoothing Radius will automatically adjust to match. Then when you're running DMap, at the point where it pauses to adjust the contrast threshold slider, you can adjust the slider so as to eliminate bright blobs in the dark areas. There's a general tutorial about DMap on the Zerene Stacker website, "How To Use DMap". It does not specifically address the situation you have here, but it does explain some of how DMap works so hopefully that will help span the gap.

There are two more things it may help to know. First is that the default retouching brush paints details, not overall color and brightness. That's by design, to facilitate retouching with PMax. But for retouching DMap in this situation, I expect you'll be happier with the Pixels brush, which just copies pixel values like Photoshop's clone tool. Second is that the process called "slabbing" may help to reduce the effort of retouching. See https://zerenesystems.com/cms/stacker/docs/slabbing for more about that. The Pixels brush and slabbing are both "Pro-only" features, so if you're using Trial or Personal Edition, you'll get a warning about needing at least Prosumer Edition to continue using those features in the long term.

--Rik
Thanks for the tips, Rik. I've been resisting using DMap for sometime now because it just wasn't working out the way I wanted on previous stacks. I'll give it another try with your suggestions.

I'm trying out a new piece of light diffusion that I expect will help with the glare too. I'll post back with some more pictures to share the comparison between my stacks.

wwheeler48
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by wwheeler48 »

I understand where you are coming from with DMap. The splurge freaked me out. But after discussions with Rik and Allan Walls I realized I was using DMap all wrong. Now i almost always use it as my retouching basis and pull details from PMap images, whether that is PMap of an entire small stack or slabs of larger stack. In addition, I often do multiple DMap at various sized radiuses. Its a great program, just takes some time to master, or in my case get semi competent

Marcepstein
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Re: Scales of a Madacascar Sunset Moth (5x)

Post by Marcepstein »

There's a general tutorial about DMap on the Zerene Stacker website, "How To Use DMap". It does not specifically address the situation you have here, but it does explain some of how DMap works so hopefully that will help span the gap.

There are two more things it may help to know. First is that the default retouching brush paints details, not overall color and brightness. That's by design, to facilitate retouching with PMax. But for retouching DMap in this situation, I expect you'll be happier with the Pixels brush, which just copies pixel values like Photoshop's clone tool. Second is that the process called "slabbing" may help to reduce the effort of retouching. See https://zerenesystems.com/cms/stacker/docs/slabbing for more about that. The Pixels brush and slabbing are both "Pro-only" features, so if you're using Trial or Personal Edition, you'll get a warning about needing at least Prosumer Edition to continue using those features in the long term.
Rik,
Thanks for the links for Dmaping and slabbing. I tried the Dmap suggestions you made in the tutorial on a stack and it worked Much better. I did have a question about the slabbing - is there a minimum number of images in a stack before you would apply slabbing? In other words, is a stack of 50 images to few too apply slabbing, for example?

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Re: Scales of a Madacascar Sunset Moth (5x)

Post by rjlittlefield »

Marc, I'm glad to hear that the tutorial helped.

About slabbing, there's no clear threshold for when it's helpful, but 50 frames definitely would not be too few to give a try.

--Rik

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