Interesting bi-color mandible on that beast!

--Rik

I am currently scanning film with Sigma 70mm art. However, this lens has quite a high and unpleasant contrast, in which I have the impression that details are lost. This sounds to me like your darks are getting clipped at black, or at least pushed below the black threshold of your monitor. This oft...

When the front to back distance exceeds the width, I get poor results. When I shoot something relatively flat and perpendicular to the lens, things go better. I agree, deeper stacks are tougher. The biggest problem I usually see is that the substantial width of the entrance cone allows the lens to ...

In truth, it strikes me as a bit "synthetic" when we shoot a series and select each image as the sharpest since every image actually used in the final composite would be would have been taken at the same distance from the camera which destroys the natural perspective where things closer appear larg...

I have not yet tried any false stereo from Zerene (actually, I resist the concept of false stereo I am curious to know what you consider "false" about Zerene Stacker's stereo images. They certainly are "synthetic", in the sense that off-axis views are derived from a single stack. But that synthesis...

Generally I prefer to avoid explanations that are based on pixel size because that opens another can of worms. https://clarkvision.com/articles/does.pixel.size.matter/#:~:text=The%20pixel%20size%20in%20digital,conversion%20limitations%2C%20and%20amplifier%20noise. That page of Clark's is exactly wh...

Nice! That's very effective at contrasting the thin flat shape of the scales against the globular shape of the amber-colored mystery object.

--Rik

So for the same framing, a crop camera has to be further away than the full frame - with Nikon the crop factor is 1.5 so presumably that means 1.5x further away. And this gives more DOF. Feff increases the closer you get to the subject. So at 1:1, given Feff = Flens(mag+1), then Flens(1+1) = 2xFlen...

Oh, I assumed it was more or less flat! Is it a spherical ball? If so then I'm reminded of silica gel. I have some larger balls that look exactly like that, but I have never checked to see if there are some small ones in the mix. Maybe a small ball of dried plant resin or nectar? Is it stuck to the ...

Some exotic weevils have scales that look something like that.

Was this a purchased specimen? If so then it may have gotten contaminated in handling at the supplier.

--Rik

https://youtu.be/J16EeaibdNE?si=gqpHpwbMwxx4k17g&t=890 https://www.youtube.com/watch?v=tynfwPHzLiU If you watch closely, you can see in each video that the barrel of the objective has several small holes that are filled with white stuff. I've been told that those holes are used to provide access fo...

Tony, I hadn't given much thought to the diffraction effects - I need to do some tests to understand the trade off there. I'm guessing it will vary by lens etc. I normally shoot at around f/13 with my Nikon D500 and Nikon 105mm and manage to end up with sharp images, especially after a bit of proces...

Lovely! You always have such interesting and unusual subjects!

--Rik

Tony, welcome aboard! I'm the fellow who wrote Zerene Stacker, and at this point, I may have studied and written more about DOF than anybody else on the planet. But I've never figured out how to write an explanation that is simultaneously correct, complete, and concise. I won't succeed this time eit...

FotoChris, that's a good point about this lens being closer to f/4 than f/2.8. ... Accurate measurements of their exit pupils would be evidence either for or against this hypothesis. Yes, that would be a very valuable measurement. Remember that for specification purposes, industry convention says t...