best lighting for entomolocal slides+ coverslip photography?

[Milou]

Hello,
As I would like to take picture, with my new Leica M420, of entomological slides (mainly genital structures with a rather relief surface), I wonder about the best lighting to use, in order to avoid bad reflections/glare on the glass slides with coverslip.....
I think to use translucent screens on 2 or more targeted lights tilted at more or less 45° (perhaps trying also an annular light?), but I'm not sure if an additional transmitted lighting would also be proper with this M 420, through slide and slip cover?
I don't know neither if flashe(s) could also be an useful complement for these slides?

Perhaps a polarizer adapter would also be necessary?

If anyone already has any experience for slides photography, thank you for your help

[TonyT]

You could light from below as done with compound 'scopes- never get reflections!

[zzffnn]

You can use reflection-free (coated) museum glass, such as TruVue or ArtToFrames. The smallest size available is around 5x5 or 4x6 in inches. They are expensive at around $30 per piece though.

I saw the TruVue museum glass in person (when I went to frame my sons’ drawings at a hobby store). It is really refection-free from any viewing angle. I have not tried ArtToFrames glass myself.

[Milou]

@TonyT
But did you get with only"bottom" light a good picture of fine irregular and uneven structures on the top of slide (eg rather thick chitinous parts) ?
In fact my slides are not as thin as eg vegetal or tissue cut!

@zzffnn
I didn't know this special glass, but in fact my slides are already made and therefore I can't use another glass!

[TonyT]

I must admit I was surprised by your question; the problem of light reflection from a coverglass has been solved many times.
Ping pong ball, styrofoam cup, tissue paper etc.
I have used a styrofoam cup to surround the slide, 2 flashes at about 45 degrees; thousands of moth genitalia images and never any reflections.
See:
http://extreme-macro.co.uk/macro-diffusers/

[Milou]

Thank you for information and link
Therefore no lighting from bottom in your setup for genitalia slides pictures!

You know, if I've experience in preparing moth genitalia, I've almost no one for schooting them
Just some try with a compound microscope of which head was replaced by tubes and a M4/3 body on top of it. And lighting with 2 halogen flexible neck + light from bottom through condenser and slide....

But now I would try to do that with a macroscope (Leica M420) I've not long ago bought .....
Therefore I've to buy flashes if my halogen neck isn't powerful enough.....

[TonyT]

Yes, most of my slide-mounted insects are with top (reflected) light.
I use flashes @ 1/250 second to prevent any blurring caused by movement.
Also, I take several exposures at different focus levels and then combine them into one image using Zerene Stacker.
You can see some of my images, including a genitalia mount, here:
https://www.microbehunter.com/microscop ... ia#p134328

[Milou]

Thank's for details of method used
Have you perhaps a picture of you setup showing how high and large is your styrofoam cup around the slide, please?

[TonyT]

A standard North American disposable drinking cup.
Can be easily cut to any length,

setup=slide-photos.jpg (112.28 KiB) Viewed 1852 times

[Milou]

Thank you
Nice setup....