Paramecium, Euplotes and an Unknown

[Mitch640]

Thanks NU, got it. How embarrassing. LOL but I do it all the time, even with my brothers, just part of retirement.

I'm not use to the terminology yet either. There is a lens in the trinocular port that is part of the scope. No way to remove it. It doesn't just lift out. On top of that, goes an adapter that came with the scope. This part has a length adjustment in it, but no glass, and it adapts to different ends, C-mount, and some others that so far are not useful with any of my cameras.

After buying a cheap E-Bay adapter, which did work to mount the camera body, but had no lens in it, I decided to try one more time, with a better, meaning more costly, model I found for the EOS mount, at Microscopenet.com. It turned out to be a very well made piece, fit right on the 1D3, fit the scope in an eyetube, and the adapter I just mentioned, and has a 2x lens built in. That seems to be the secret, the adapters do need a lens inside them, and I have seen other adapters, even more expensive, that all have lenses built in.

One more thought that has been tumbling around inside what's left of my mind, and I learned this when shooting more conventional subjects, is the coatings on the lenses used in microscopy. These coatings, whether they be on lens or filter, need to be multi-coat and specifically made for digital sensor cameras, or you get all sorts of chromatic aberrations, lines, and other artifacts you do not get with made for digital coatings. I just doubt that many scope manufacturers coat their glass with these made for digital coatings. Maybe it can't be done. Coatings have thickness in themselves that might change the whole anatomy of the lens itself. I don't know. But I do know this well known problem in regular photography when I see it.

Here's the link to the adapter.

[Charles Krebs]

That should be a good adapter for the 1D size sensor. (2X is just about right for that sensor size... 19.1x28.7mm. Hopefully the optical quality is good).

need to be multi-coat and specifically made for digital sensor cameras, or you get all sorts of chromatic aberrations, lines, and other artifacts you do not get with made for digital coatings.

Not really... flare yes, but not chromatic aberrations. Digital cameras definitely do seem to have a larger issue with flare than film cameras due to the extremely flat surface of the filters sandwiched onto the sensor. Multi-coating is certainly important, but the shape of optical elements also plays a big part. (And multi-coating has gotten better and more effective over time, but there is no magical "digital" coating).

On the microscope it seems that many of the relatively inexpensive USB "eyepiece" cameras have reduction lenses (to fit the intermediate image onto the small sensor) that cause flare issues, often seen as a circular or ring-shaped "hot-spot". Also, it's not that unusual to see the same thing when the afocal method is used, (camera with camera lens attached, pointed into "regular" eyepiece). Often this is due to the shape of glass elements in the eyepiece.

[Mitch640]

Charles, check this thread out. This happened to me, and many other people, when using cheap, or old film, filters. This is what I was talking about. Not sure if it's the same thing happening with my scope, I don't see diagonal lines, but the colors are certainly way off, or non-existant. I see colors in the eyepiece that don't come through to the Canon or my eyepiece USB video cam. It may not be the coatings, but it's definitely something.

[rjlittlefield]

Charles, check this thread out.

Perhaps not the best of references, since the OP in that case also writes that

I have mentioned a couple of times that I have tried it with & without the UV filter.

It's too bad that final resolution of that problem was never posted. As other posters pointed out, it was clearly a bokeh problem, affecting only OOF areas. That implies either a malfunctioning aperture or a large amount of some asymmetric aberration. There's something to be said for the final poster's suggestion of a fingerprint on the rear lens element.

In any case, I believe Charles' point is that digital sensors should be no more or less sensitive to this sort of problem than film. If you're aware of evidence to the contrary I'd be interested to read about it. As it stands, I'm inclined to imagine that the reports are due to other changes that came along with the digital sensor, like say new lenses that might be more sensitive to filter imperfections. A head-to-head comparison with everything the same except the camera would be very interesting.

...but the colors are certainly way off, or non-existant. I see colors in the eyepiece that don't come through to the Canon or my eyepiece USB video cam.

Hhmm...this is a puzzling problem. Does the lack of color persist when you use the workflows suggested by Pau and Charles? If so, then again using a static test subject, can you characterize which colors are missing?

--Rik

[Craig Gerard]

Oh, and that linked thread was just beginning to get interesting. The last post may have 'nailed' the problem; but we will never know how the story ended

Mitch, I am also curious about the "colors" you've mentioned. Do you notice the presence of those "colors" when using a standard viewing eyepiece in the trinoc tube for observation? You have indicated the USB eyepiece camera has the same, deficiency, if that is the appropriate word and if I have understood your visual assessment correctly. How severe is the difference, is it a colour space issue?

Craig

[Charles Krebs]

Not sure what your problem might be. Could be a flare issue.

Craig's suggestion is a good one... put a regular viewing eyepiece in the trinocular tube and see if it "matches" what you are seeing through the viewing ports.

Next I would place a slide on the microscope and focus on a subject. Leave your adapter in place and remove the camera body. Look down the trinocular tube, through the adapter and move your head around so you are looking through at different angles. See if there are any internal surfaces that appear as if there is bright light being reflected off of them. Try it again with the camera adapter removed so you are looking down the empty trinocular tube.

(I don't really see any obvious flare issues in the three shots you have posted here. As far as color goes there's no real color in these three subjects so it's tough to make any judgment in this regard based on these shots.)

[Mitch640]

As for the filter problem in that other thread, my cheap filter would cause the lines in the background, and take it off, using the same camera, they would go away. This happened over several models of Canon bodies, until I got rid of the filter. Of course, then I quit thinking about it, but I kept the bookmark, cause others were coming up with it and I would see it occasionally in other posters images and bring it up. Getting rid of the filters always solved the problem. Which doesn't mean your going to get that problem with microscope lenses. I bring it up, cause something is causing a problem.

As for what I see with my eye, I see lots of greens and some reds, and occasionally blues. Not all from living organisms. It seems the water from the Mississippi has a lot of blue and red fibers of microscopic sizes in it and I see them in almost every drop of water I look at. The greens seem to come through in images, although a little muted, the reds occasionally, but they are very muted, and blues seem to be missing altogether. On the other hand, yellow seems to show up a lot, and there is no yellow when looking by eye. This is probably why my first thought was coatings were the problem. I'll see if I can find an example next time and record it. Maybe someone needs to come up with a color wheel on a microscope slide, like the measuring ones.