Olympus prism dimensions

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Macro_Cosmos
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Olympus prism dimensions

Post by Macro_Cosmos »

Hi everyone!

Edit: found a cheap U-ANT offered by a contact, lucky.

Additionally, the thickness and diameter of DIC prisms for UIS/UIS2.

My condenser (U-UCD, neither the B nor 8, it's likely a renamed BH2-UCD) came with these weird things:
condense.jpg
I was initially excited, thought I scored an absolute steal as it came with 4 DIC prisms. Looking at them now, they don't look like DIC prisms at all. Anyone has a clue? They sort of look like infrared bandpass/notch/high-pass filters because they are so dark, but a couple has this circular pattern on the optics.
Haven't received it yet.

Thanks for your trouble, appreciate the help.
MC
Last edited by Macro_Cosmos on Tue Sep 01, 2020 2:12 am, edited 2 times in total.

Ichthyophthirius
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Re: Olympus U-ANT and prism dimensions

Post by Ichthyophthirius »

Macro_Cosmos wrote:
Mon Aug 31, 2020 12:55 pm
Looking at them now, they don't look like DIC prisms at all. Anyone has a clue? They sort of look like infrared bandpass/notch/high-pass filters because they are so dark, but a couple has this circular pattern on the optics.
Are they not simply ring apertures for phase contrast?

Perl
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Location: Sweden

Re: Olympus U-ANT and prism dimensions

Post by Perl »

phase disc
try to make you own pol filters and DIC prismas
much cheeper :shock:

Best Regards
Pär
****** Seeing is Believing ******

René
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Re: Olympus U-ANT and prism dimensions

Post by René »

sounds great Par, but how do you suggest to make yourself the DIC prisms?

Regards, René

Macro_Cosmos
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Re: Olympus U-ANT and prism dimensions

Post by Macro_Cosmos »

Ichthyophthirius wrote:
Mon Aug 31, 2020 3:29 pm
Macro_Cosmos wrote:
Mon Aug 31, 2020 12:55 pm
Looking at them now, they don't look like DIC prisms at all. Anyone has a clue? They sort of look like infrared bandpass/notch/high-pass filters because they are so dark, but a couple has this circular pattern on the optics.
Are they not simply ring apertures for phase contrast?
They look too dark though, I initially thought they were PH discs too.
It could be an angle and underexposure. I think you're right.
Still a good deal then. I can sell these rarer big PH discs off.
They should be for the BX ones. The other under the dry top is likely the darkfield ring.
Then they still look weird, maybe it's a DIY part... I thought those discs have 3 thin sections joining the concentric circles. Manufactures probably do this to make mass manufacturing easier.
annuli.jpg

Ichthyophthirius
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Re: Olympus U-ANT and prism dimensions

Post by Ichthyophthirius »

Macro_Cosmos wrote:
Tue Sep 01, 2020 12:47 am
Then they still look weird, maybe it's a DIY part... I thought those discs have 3 thin sections joining the concentric circles. Manufactures probably do this to make mass manufacturing easier.
The condenser phase annuli were originally made from a photoresist layer on a glass disc (Zeiss, Leitz) and didn't have the three arms holding the centre. The newer ones are cut out from plastic (no doubt cutting costs as well) and need the three arms to hold the centre in place.

You can see a phase annulus like these in this study https://media.springernature.com/lw685/ ... pg?as=webp but it's not 100 % clear from the paper if it was custom-made.

"N" could mean narrow, "W" could mean wide, that would explain why there are two different annuli for 20x ... so maybe this is an experimental setup ...

Macro_Cosmos
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Re: Olympus U-ANT and prism dimensions

Post by Macro_Cosmos »

Ichthyophthirius wrote:
Tue Sep 01, 2020 2:37 am
The condenser phase annuli were originally made from a photoresist layer on a glass disc (Zeiss, Leitz) and didn't have the three arms holding the centre. The newer ones are cut out from plastic (no doubt cutting costs as well) and need the three arms to hold the centre in place.

You can see a phase annulus like these in this study https://media.springernature.com/lw685/ ... pg?as=webp but it's not 100 % clear from the paper if it was custom-made.

"N" could mean narrow, "W" could mean wide, that would explain why there are two different annuli for 20x ... so maybe this is an experimental setup ...
I've actually briefly skimped through this study as I was ravaging the net for a condenser, finding every obscure source I can land on. I just assumed their rings were DIY.
That explains a lot then, this UCD is definitely old. I really hope it's compatible with my DIC prisms that are also coming, or else I'll be pretty well... upset to say the least.

Do you have the diameter of these discs in mind? I want to experiment with a kind-of-DIY "UCD" setup and compare the results.

Thanks!

Ichthyophthirius
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Re: Olympus prism dimensions

Post by Ichthyophthirius »

The DIC inserts have a mini-dovetail to fit into the condenser centering mechanism.

Prism U-DPA40:

upper diameter of insert: 29.95 mm
minimum dovetail diameter: 27.90 mm (difficult to measure)
bottom dovetail diameter 29.95 mm
insert hight: 5.36 mm

They also have a pin that keeps the prism insert in place and in the correct orientation. The pin fits into a notch which fortunately is present in your condenser positions!

Macro_Cosmos
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Re: Olympus prism dimensions

Post by Macro_Cosmos »

Ichthyophthirius wrote:
Tue Sep 01, 2020 6:06 am
The DIC inserts have a mini-dovetail to fit into the condenser centering mechanism.

Prism U-DPA40:

upper diameter of insert: 29.95 mm
minimum dovetail diameter: 27.90 mm (difficult to measure)
bottom dovetail diameter 29.95 mm
insert hight: 5.36 mm

They also have a pin that keeps the prism insert in place and in the correct orientation. The pin fits into a notch which fortunately is present in your condenser positions!
Thanks! 30mm, that should be workable.
I think this condenser has some kind of centering thing too, there's a bunch of dials and screws. Only info I can find is a repair manual on Alan Wood's website, who also posts here.
http://www.alanwood.net/downloads/olymp ... manual.pdf
This is assuming the bh2-ucd is the same as the one I have.
"Two allen wrenches for centering the elements are provided."
Hopefully it's as good if not better than the U-UCDB types. The U-UCD8 manual even suggests the user to swap the antenna out for set screws. I've found out that with the antenna, it's easy to knock the filter wheel, thereby making the entire centering effort futile. Those with the U-PCD should know what I mean.

I somehow think the UCD condensers is just one of these with a filter wheel.
download.jpg

If that's true, then it's entirely possible to DIY based on the more commonly available swing-out condenser, that's also cheaper (paid $120 for mine).

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