two coin images (images added)

Images made through a microscope. All subject types.

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nielsgeode
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Post by nielsgeode »

rjlittlefield wrote:
Litonotus wrote:I remember that there WAS a solution for that highlight problem (without processing of course), unfortunately I do not remember it now
Are you thinking of "burning in"? This was a darkroom technique to recover detail from dense parts of a negative by giving them a longer exposure during the printing step. If you're talking about something to be done in setting up the shot, then I don't know any solutions other than careful lighting and sometimes use of polarizers (not applicable here with a metal subject).

--Rik
Why are polarizers not applicable when you have a metal subject?

Niels

rjlittlefield
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Post by rjlittlefield »

nielsgeode wrote:Why are polarizers not applicable when you have a metal subject?
With non-metallic subjects, polarizers are very helpful because 1) sub-surface reflections are non-polarized regardless of the illumination, while 2) surface reflections retain any polarization provided by the illumination and may be partially polarized even if the illumination is not. This combination allows surface (specular) reflections to be reduced or eliminated by cross-polarization.

With metallic subjects, all reflections simply retain the polarization of the illumination. If you try cross-polarizing to reduce the brightness of the hot spots, the brightness of almost everything else simply drops by the same proportion so you end up pretty much back where you started except for reduced exposure overall.

--Rik

Litonotus
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Post by Litonotus »

another try, I used a paper made cone-shaped diffuser here. I will try pingpong ball soon (:

they are technically better but when it comes to visual aspects I like better previous ones...

Image

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my FB page

I'm looking for the the extemely rare V-IM magnification changer for the E800 scope. If you have seen a listing or have one for sale please let me know.

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