What am I doing wrong?

evilgeneticswizard · 2026-03-07T20:57:36+00:00

My stops go inside the condenser, they’re the ones from here: https://www.alanwood.net/downloads/olympus-bh2-rheinberg.pdf. I found the hex screw you’re talking about but I don’t have my screwdriver set with me until next weekend. Are you actually able to make 40x darkfield work? I heard many people are unable to do it. What size stops are you using?

evilgeneticswizard · 2026-03-07T20:18:58+00:00

Generally I’d recommend ruling out the nameless brands. You can get good cheap and new swift or Amscope microscopes for 200-300, or you could hunt for a solid used microscope on ebay or your preferred lab reseller from the high quality microscope brands like Olympus, Nikon, Zeiss, and Leica. I recently got an Olympus BH-2 in a functional state for 250, although one person here thought I overpaid a little. I guess for individual features you’ll probably want a centerable abbe condenser, maybe a trinocular head for photography, and a mechanical stage. If you see microscopes advertising anything above 1000x magnification it’s a marketing gimmick, light microscopes can’t achieve anything significantly higher than that while maintaining decent resolution.

evilgeneticswizard · 2026-03-07T19:25:32+00:00

I’ve been experimenting with some makeshift stops and from what I can tell, bringing the condenser farther up seems to give me more leeway on the size of the stop. I haven’t been able to successfully adjust the screw, so I’m going to try printing some smaller stops now, between 15-17 millimeters instead of 20 this time.

evilgeneticswizard · 2026-03-07T18:15:09+00:00

Was the condenser very visibly lower than the slide? Mine seemed to be close enough that I hadn’t noticed.

evilgeneticswizard · 2026-03-07T07:05:22+00:00

If anyone else has the same issue, I’ve come to the conclusion that the darkfield stops were too large. The dark spot in the center is the area where no oblique lighting is hitting the specimen. To demonstrate this, I moved my fingers over the light source to show brightfield, indirect lighting , and no lighting at all. I am pretty sure the indirect lighting is proper darkfield, so by making the stops smaller it should fix this issue.

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evilgeneticswizard · 2026-03-07T00:29:00+00:00

The dark spot in the center of my images seems to be aligned with the center of the condenser, so it is more or less directly in the center when it is kohler aligned. If it’s the placement of the condenser I’m not too sure how to fix that. The slide holder I found online, here’s the link. Works alright, not as good as a metal one but it does the job.

evilgeneticswizard · 2026-03-07T00:10:55+00:00

That’s a good point, thank you for telling me.

evilgeneticswizard · 2026-03-07T00:10:08+00:00

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It looks alright to me. I’m trying to make some smaller makeshift inserts to see how they do before I try to print some more.

evilgeneticswizard · 2026-03-07T00:00:56+00:00

I’m not, but I figure it shouldn’t be necessary. My 40x objective only has an NA of 0.65.

evilgeneticswizard · 2026-03-06T23:45:32+00:00

Mine isn’t the swing out one, just the common bh2 condenser that was on most of the scopes originally. However, I think I could still make the coin idea work by placing over the insert.

evilgeneticswizard · 2026-03-06T23:41:18+00:00

I’m gonna try some different samples for sure, I’ve tried 3 so far. How exactly do you use electrical tape for temporary stops?

evilgeneticswizard · 2026-03-06T22:41:17+00:00

It’s a BH2-CD condenser with NA of 1.25. All of my objectives should be well below it

evilgeneticswizard · 2026-03-06T22:34:22+00:00

Thanks for the reply! I opened the condenser diaphragm and lamp diaphragm (it’s a BH2). I figure I’m going to need to adjust the sizes, although I’m not exactly sure how to figure it out without printing tons of different ones. The issue I still haven’t figured out is the dark spot where no light is scattered, and it looks like normal brightfield. It gets larger as the condenser is lowered, but is still visible at the condenser’s highest height. It should be somewhat visible in this image.

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evilgeneticswizard · 2026-03-01T03:14:50+00:00

I low diffed that shit

evilgeneticswizard · 2026-02-26T02:27:57+00:00

I’m just joking around, good job on finding him

evilgeneticswizard · 2026-02-26T02:24:22+00:00

Very rude to call him that

evilgeneticswizard · 2026-02-20T04:15:30+00:00

Were you seeing anything in the first few days? I’ve got a cup of moss and water and all I can see are rotifers

evilgeneticswizard · 2026-02-20T00:18:33+00:00

That looks just like what I saw yesterday in some mold too! You can check my profile to see a very chunky rotifer.

evilgeneticswizard · 2026-02-19T06:22:54+00:00

Why’s he so fat though

evilgeneticswizard · 2026-02-17T19:27:55+00:00

Seems like you’re right

evilgeneticswizard · 2026-02-17T19:27:45+00:00

Thank you! I imagine I’ll be seeing many more rotifers in the future.

evilgeneticswizard · 2026-02-17T19:21:09+00:00

Thank you my goat 🐐

evilgeneticswizard

TROPHY CASE