Moth Wing Scales

[Olympusman]

From Giant Leopard Moth

[Beatsy]

Nicely resolved "ladders" there, especially in the second image. Quite a bit of CA in the first though - was that done with an achromat?

[Olympusman]

Don't know if my 20X objective is an achromat - probably is. It is a 20X non-Plan from an Amscope microscope. Nothing special. But, from my experience, chromatic aberration can occur along any edge where there is a strong difference in contrast.
When I worked for a tech rep at Olympus, a new Camedia software for Olympus cameras would come out with a CA correction feature that I would need to assess. I knew which cameras to grad and what conditions to shoot under (usually the windows of Dunn & Bradstreet across the street).
Eliminating chromatic aberration does not come cheap. With the advent of HD video recording becoming more common and ambitious filmmakers want to shoot movies with hybrid still/HD cameras, their demands for image quality will be challenged. This is why optics companies such as Zeiss are remounting their cine lenses into digital camera mounts.
The difference between a consumer still camera lens and a professional cine lens? 8 to 10 thousand dollars. Tell me the last time anyone saw CA in a theater.

Still pushing the limits this side of empty magnification...
Mike

[Beatsy]

Don't know if my 20X objective is an achromat - probably is. It is a 20X non-Plan from an Amscope microscope. Nothing special.

Still resolves the necessary though. Thanks for the extra info.

Eliminating chromatic aberration does not come cheap.

Tell me about it! As a happy (but poorer) owner of all three Zeiss Otuses in the set, I could ask "what's chromatic aberration?" but even Otuses can exhibit longitudinal CA against very high contrast edges. It's barely a 4.5 micron pixels-worth and has never been a problem in practice - but it's there.

Tell me the last time anyone saw CA in a theater.

Indeed. But I'd give you odds that a few here *do* look for it!

[Pau]

Don't know if my 20X objective is an achromat - probably is. It is a 20X non-Plan from an Amscope microscope. Nothing special.

If nothing else is written on it it's just an achromat for sure. I suppose you used a better corrected lens for the second image.

[Lou Jost]

This seems like a good situation to use one of astrophotography's "fringe-killer" filters or low-pass filters, which are designed to reduce purple fringing in achromat telescopes. A famous one is the Baader fringe-killer but they (Baader) make several varieties. I am thinking of experimenting with one.

[Beatsy]

This seems like a good situation to use one of astrophotography's "fringe-killer" filters or low-pass filters, which are designed to reduce purple fringing in achromat telescopes. A famous one is the Baader fringe-killer but they (Baader) make several varieties. I am thinking of experimenting with one.

Those just kill the extreme ends of the red and blue parts of the spectrum, don't they. Could be a pretty good solution for colour images. Look forward to your results...

Of course, the trusty old green filter (then convert to black & white) serves admirably where colour is unimportant (like these butterfly scales).

[Lou Jost]

Yes, these cut the extremes, leaving a slight color tint that should be correctable in post-processing.