Pol/DIC

[Mindwarp]

Hello gang,

I have a newbie question :
Some of my objectives are Pol ones. When I use an adequate DIC prism (and adequate condenser) with these polarized objectives it seems to work quite well as a DIC set up. Does I do/have something wrong ?

[viktor j nilsson]

Pol objectives have been checked by the manufacturer to make sure that they are strain-free. This means that the objective doesn't affect the polarization state of the transmitted light. Since both DIC and polarization microscopy rely on polarized light, both techniques need objectives that are strain-free.

In many cases, pol and non-pol objectives are identical, the ones marked pol just go through an extra inspection before being marked as such. Very many objectives that aren't marked as Pol works perfectly well for DIC and polarization work.

[Mindwarp]

Very interesting piece of information @Viktor. Does it leans that I do not need DIC Neofluar to achieve DIC (as long as the condenser and the prism bounty fit) ?

[viktor j nilsson]

I can't say that for sure. DIC compatibility is determined by several factors, in particular objective focal length and location of back focal plane. Objectives with the same magnification from the same manufacturer will typically have the same focal length and the back focal plane will often, but not always, be located at a similar position. So it wouldn't surprise me if your objectives work, even if they aren't the ones specified by the manufacturer. Just try it and see if you are happy with the results. If you are, I wouldn't worry too much. Go search for DIY mismatched DIC or something like that, you might be surprised at the number of crazy combination that work well.

[viktor j nilsson]

Here's a good thread:
https://www.photomacrography.net/forum/ ... sc&start=0

If you are using matched objective and condenser prisms on the correct stand, and objectives from the same manufacturer, then you are a lot closer to what the manufacturer intended than a lot of the examples in that thread!

Many manufacturers recommend relatively simple plan Achromats for their DIC equipment. Presumably because these simpler designs are less likely to develop strain in the production process. But many users use planapo's with good - I would say superior - results.

[Mindwarp]

@viktor, thanks you a lot. These article are a huge source of more than precious informations...