Things that I have - what can I do with them?

Starting out in microscopy? Post images and ask questions relating to the microscope and get answers from our more advanced users on the subject.

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ChrisJones
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Things that I have - what can I do with them?

Post by ChrisJones »

My current vague goal is to be able to take decent images of Drosophila melanogaster. At the moment all I have set up is SMZ800 with a VariMag II and a Nikon D5200, which is reasonably simple, but not amazing. I had a poke around in the lab today to see if I could find anything with potential to produce better images. We have various microscopes, but most are in use and any spare objectives tend to be too high magnification (>10x).

I did find an Olympus CK2 inverted microscope plus phototube that's not being used:
Image

Unfortunately I couldn't find any photo eyepieces or any of the rest of the bits required to attach a camera. I may be able to attach my VariMag with an adapter though (I need to check with the company, the CK2 is not listed specifically). However, I'm not sure how useful an inverted microscope could be for my purposes. I'd have to light the fly from below, which could be a problem.

The alternative I have is to do something with the objectives from the CK2, or a spare Zeiss objective:
Image

Unfortunately I don't know if any of these are any good, or what kind of setup they would need. Could I do something with a 70-300mm lens?

Charles Krebs
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Post by Charles Krebs »

The trinocular head has a "standard" 23mm tube. There should be no problem at all putting your VarimagII onto this. One "catch" is that the Olympus objectives you show all were intended to be used with eyepieces and photo-eyepieces that were corrective (for photo-eyepieces, specifically the NFK series). You'll need to try it and see how bad the uncorrected chromatic aberration will appear in the pictures. The three Olympus objectives you show are very "basic" models. Still, I would expect better images than you showed earlier, especially with the 0.25NA of the 10X (as long as the CA mentioned earlier is not too severe).

The Zeiss is an infinity type objective. The tube lens focal length for Zeiss is (IIRC) 164.5mm, and it also provides some color correction. So it is not the best candidate for mounting on a camera lens. I would however give it a quick test on your 70-300 since you already have both. You never really know how problematic the (uncorrected) color problems will appear until you try it.

ChrisR
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Post by ChrisR »

For a whole fly you'll need the 4x? I've tried an Olympus 4x 0.1 on a camera, ie without any CA correction. I regret to report, that I don't think you'll like it :( .
If you go the "infinity objective on camera lens" route, it would give you, with a base-model NA 0.1 and your 300mm,
4*(300/200) = 6x, but at effective aperture
6/(2* 0.1) = "F30" = not too bad but not great either.
At least you can use that Narishige(?) manipulator to hold it up :)

You'd be about as well using a reversed enlarger lens (<50 £/$ used) on some cheap extension tubes (<10£/$ new).
Last edited by ChrisR on Mon Apr 08, 2013 2:40 pm, edited 1 time in total.

Pau
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Post by Pau »

I agree, an inverted microscope isn't the best option for this kind of work.

I would try the Zeiss 10X coupled on the zoom, perhaps the combo may provide enough coverage.
Some time ago I took this pictures with an infinite Nikon 10X on a zoom
http://www.photomacrography.net/forum/v ... 2970#62970

As Charles says this objective do need some CA compensation but if it is not too big you may deal with it shooting RAW and correcting it during the RAW conversion.
(all I say is a bit too speculative, but you can test it with very little inversion: just a flat RMS to your filter thread adapter)
Pau

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