MicrobeHunter.com Microscopy Forum

Unless you can 3D print optical lenses, you will need to buy an apochromatic reducer, or use no reducer at all. Oh that's interesting. I didn't know it was a thing! Do you know any model I can check? I also tried without any reducer but my sensor is too small and the image is heavily cropped. I can...

Hello, I'm looking for a way to replace a Touptek FMA050 camera adapter. It seems to add a lot of chromatic aberration. Do you know something better to mount a C-mount camera on a custom microscope? It's a small sensor: 1/3" I can 3d print an adapter to fit the microscope if needed (it's a PUMA micr...

Frequently a 1x compound objective will need a contrast cap, especially for reflected light applications. A polarizer is placed in the light path, and the contrast cap is mounted over the front of the objective. It is essentially a 1/4 wave plate that can be rotated for the best contrast as you obs...

The "Spezial" is for use with the Jenaval scopes with a special condenser : (page 8) https://www.zeiss.com/content/dam/Microscopy/us/download/pdf/end-of-service/upright/upright-jenaval.pdf I think the condenser is called "Aplanat 0.12", it's a rather elaborate process. EDIT: by the way, I think the...

Hello, So I finally bought the complete set from the same seller (sadly, no 100x oil in the set) and I got a weird objective. The one on the left: jena GF planachromat.jpg No infinity symbol on it: 1 x 0,03 spez/-A I tried it with the same setup than other objectives but I don't have any image. Any ...

Oh I see, thanks!

Illuminations techniques are really an interesting subject.

Thanks for the precision. I'm not really sure why I have more troubles to understand Köhler in epi illumination, but I'll have to play with a real world application to understand I guess :roll: This kind of modular epi illumination seems pretty cool: https://www.thorlabs.com/newgrouppage9.cfm?object...

Thank you.

But in the case of epi illumination, the objective is the condenser right?
It is the same than an infinity condenser?
That's why I was wondering if parallel beams were needed in this specific case.

Hello, Maybe this is a stupid question, but is there any difference between epi Kölher in a finite and infinity corrected system ? Isn't the light beam supposed to present to the infinity-corrected objective as parallel rays? But in this case the light source image can't form at the objective back f...

So, I received and tested the objectives on my Olympus BH2 with the epi head. The quality is really good and I'm pretty happy. Using the 1.5x magnification of the magnification wheel. GF Planachromat 50x/0.80 using focus stacking and channels alignment: 50x-1.5_FS.jpg By comparison my LWD MSPlan 50x...

Thank you. I'll try to buy a 50x and a 25x.
They are 50€ each, seems to be a very reasonable price for this kind of objectives.

-A means it is internally corrected (ie part of the CF250 system, using a 250mm focal length tube length neutral tube lens, no eyepiece corrections). -This one is meant for reflected light )but you could get away with transmitted light.) -I believe they have a 25mm thread. -250mm Oh, so the A is go...

Hello, I can get some Gf-Planachromat objectives, but I'm not 100% sure of the specs. I would like some details before deciding to purchase them. aus JENA GF Planachromat 25x / 0.50 ∞/0-A My questions: - What does 0-A mean? I guess 0 is for 'no coverslip' but this is the first time I see this A - Ca...

Saul wrote: ↑

Fri Mar 01, 2024 9:24 pm

Impressive ! What is used to control steppers ?

Thanks! A RAMPS board / Arduino mega / TMC2208 drivers.
Something that was very common for controlling 3D printers a few years ago.

Hello, Here is my Olympus BH2 I motorized some time ago. motorized_bh2_50p.jpg I also made a frame/box to protect it from dust. It works pretty well. I'm using it to make microchips captures. TL082CN_small.jpg It is precise enough to capture images with a 100x/1.25 oil objective. Some of my captures...

Thank you very much for the detailed answer.

I don't think the objective have been dismantled.
It was a demonstration objective from what the seller told me. So it should be almost new.

Too bad.

Scarodactyl is correct. The objective has most likely been disassembled without observing and marking the original alignment of the lens cells and then reassembled carelessly. The seller is incorrect. The objective can likely be repaired but with considerable effort and time. I would try to return ...

I can return the objective, that's why I want to know for sure. I know some corrections are also made in the tube lens, but I don't think it explains the difference between my 100x/80x and this 40x. Reconsider that point. Do you think because it is an apochromat it will pose more problem than my oth...

Scarodactyl wrote: ↑

Wed Feb 21, 2024 6:31 pm

I think your objective is decentered or otherwise borked. Darn shame.

Oh no

Any tests I can do to verify this?

Edit:
I made some videos of the focusing, just to be sure:
https://youtu.be/fFSmYJn81VM
https://youtu.be/ASY_i08vNC4

Hello, I have an Olympus BH2, with the vertical illuminating system and infinity corrected objectives. Default objectives are MSPlan objectives. But I also use with success (and a neutral eyepiece) two other objectives. An Olympus Plan 100x/1.25 oil infinity/- And a dry Zeiss 80x/0.95 infinity/- obj...

Macro_Cosmos wrote: ↑

Tue Feb 20, 2024 2:58 am

onilink_ wrote: ↑

Sun Feb 04, 2024 10:48 pm

Is there a version with values < 1.0x? (It is even possible?)

No, but it is possible. I have seen an off-brand BX (u-ca) one with 0.5x.

Thanks! It's good to know.

Oh it's really a great piece of documentation, with lots of terms I didn't know.

Thanks a lot!

Thank you for your answer dtsh!
I'll try to experiment with that.

There's a sort of carousel inside, typically with achromat doublet lenses for the magnification and often a Bertrand lens. Not sure Olympus made one with something below a 1x magnification. Thank you for your insight! So in theory, if I place an achromat doublet at the same position, I should see s...

Hello,

Is there a simple method for determining the back focal plane of any 160mm biological objective?

I have an Olympus BH2 and it seems that my magnification changer has a Bertrand lens.
Would that be useful?

Thank you

Hello, Can anyone explain how the magnification changer works on the Olympus BH2 systems? What type of lenses are we talking about? Is there a version with values < 1.0x? (It is even possible?) On my case it is placed after the vertical illuminator (a BH2-MA, and I have MSPlan objectives), but I ima...

Your BH2 does NOT have an infinity corrected optical system, it is finite so a NFK correction eyepiece IS required. I have the epi-head and the objectives are infinity corrected, so my BH-2 is a strange beast :mrgreen: But yeah I know I need the NFK. That's why I bought it. Using the L-tube or the ...

If you want a round image, you will need to shoot through the eyepiece afocally. That's what it's called when you shoot through the eyepiece like you look through it as you would with a cell phone. Parfocality is having the eyepiece and camera views in focus together at the same place. When you loo...

I use the U-PMTVC and a 3.3x NFK projection lens for my Panasonic GH4 to shoot 4K video. I get the eyepiece corrections from the NFK, and the frame size reduction back to essentially direct projection (3.3x x 0.3x = 0.99x). Even that's only good, not perfect. And as I recall, not all that good for ...

Compensation is a way of evening out the various aberrations in an optical system by first overcorrecting in one component and then undercorrecting in another downstream component. The undercorrecting component is called a compensating lens and more often than not is usually a compensating eyepiece...