nikon BD vs M objectives

[blekenbleu]

If I was wanting to do a DIC setup would standard bdplan objectives work? Also i some kind of prisms needed for the head. I see lots of them for nosepiece and nothing for the head.

Some were marked specifically for DIC, but BD Plan objectives seem to work fine;
DIC prisms should be close to objective back focal plane.
I have read about placing a DIC prism on the objective before screwing into the nosepiece turret.
Slider in head is analyzer (polarizing filter) required for DIC; orientation of analyzer to prism is critical:
https://www.microscopyu.com/tutorials/w ... microscopy

[Scarodactyl]

If I was wanting to do a DIC setup would standard bdplan objectives work? Also i some kind of prisms needed for the head. I see lots of them for nosepiece and nothing for the head.

The only prisms you meed are the ones built into a dedicated epi dic nosepiece. There are like three compatible models, but I'd be careful with this one:

Because it's way overdesigned mechanically, movement gets stiff very easily and it is hard to fix. Check to make sure all the prisms appear to be in it and that they say it moves smoothly. But if you find one really cheap all bets are off of course.
Aside from that as blekenbleu said you just need a polarizer and analyzer, but you do need the rotating polarizer to get full control over the effect.

[viktor j nilsson]

But that nosepiece is RMS, so the BD objectives won't fit with their larger diameter thread, and an adapter would add some length and push the objective back focal plane away from the inference fringe, which can be highly detrimental. So I'd stay with M Plans, but you likely won't need the 'DIC' marked ones as they should be optically identical to the non-DIC ones, just guaranteed to be strain-free. But most objectives are strain-free enough for DIC.

[Scarodactyl]

But that nosepiece is RMS

The one pictured has m26 threads for bd plans. They also made a 4 position bd plan one with better mechanics and iirc there was one other m26 variant but I am not certain, it's been a while.

[viktor j nilsson]

But that nosepiece is RMS

The one pictured has m26 threads for bd plans. They also made a 4 position bd plan one with better mechanics and iirc there was one other m26 variant but I am not certain, it's been a while.

Oh cool, I've only held the RMS versions in my hands. Sorry to confuse!

[blekenbleu]

They also made a 4 position bd plan one with better mechanics

Most of the Optiphot BD Plan DIC turrets seen on eBay appear to be missing prisms:

[Scarodactyl]

Sad but true.

[phansen39]

It looks like the prisms block the darkfield on the bd objectives?

[blekenbleu]

It looks like the prisms block the darkfield on the bd objectives?

Yes, there is no darkfield DIC; pull out prism slider for darkfield.

For completeness, eBay currently lists an Optiphot DIC BD Plan Nosepiece
shown with prisms... but it is bent: https://www.ebay.com/itm/324897639962

Optiphot 210 tube length BD DIC nosepiece has a compensating lens above the turret:

Whether an unbent EPI nosepiece part is compatible with bent EPI DIC part seems unlikely.

Weirdly, there are a couple of listings for Optiphot 100 DIC microscopes,
which are Optiphot 2 frames with vertical illuminators having a tube lens for infinity objectives,
but they instead have finite Optiphot DIC BD nosepieces and/or objectives:

• this one even lists 210 objectives:

https://www.ebay.com/itm/202650186163

• This one does not, but some objectives have finite knurling:

https://www.ebay.com/itm/204074584066

This one appears to have Optiphot 100 EPI DIC parts that match:
https://www.ebay.com/itm/224572548833

[Scarodactyl]

Weirdly, there are a couple of listings for Optiphot 100 DIC microscopes,
which are Optiphot 2 frames with vertical illuminators having a tube lens for infinity objectives,
but they instead have finite Optiphot DIC BD nosepieces and/or objectives:

• this one even lists 210 objectives:

https://www.ebay.com/itm/202650186163

You can get away with this since both the finite and infinity illuminator will only have empty space between the objectives and head, and the height is about the same. The finite heads are smaller than infinity ones but not by much and you can just screw the thumbscrew in further. The apertures on the illuminator might be in the wrong position, not sure by how much. But it would function.

[phansen39]

Those prices are way out of budget. lol. I will keep looking. Got an offer for an 4 part M turrent with 2 prisms for 300 us. It has the 5 and 20 prisms. Dont know what prisms go in for a 10 and maybe 40 or 60x objective. I have 40x bd and would like to try 60x Also have a 40x m plan. 2.5 x m plan. Got a good deal on a 5x and 10x but they are coming from japan. Anyone know which prisms match this dic nosepiece?

[viktor j nilsson]

Those prices are way out of budget. lol. I will keep looking. Got an offer for an 4 part M turrent with 2 prisms for 300 us. It has the 5 and 20 prisms. Dont know what prisms go in for a 10 and maybe 40 or 60x objective. I have 40x bd and would like to try 60x Also have a 40x m plan. 2.5 x m plan. Got a good deal on a 5x and 10x but they are coming from japan. Anyone know which prisms match this dic nosepiece?

That's the one I have. The two missing are two identical prisms labelled 10.40.100x.

[phansen39]

Have a pic on what they look like?

[viktor j nilsson]

Have a pic on what they look like?

Well, I have one image of them disassembled:
https://www.microbehunter.com/microscop ... 63#p111763

[phansen39]

Thanks, So a small square in a square metal frame.. Have any of to 10,40,100 left?