Objective Identification.

[Tesselator]

I've been reading about photography using microscope objectives for a few years now (I know, I'm slow) and decided to give it a try. I have a garage full of microscopes new and old (though mostly old) and wouldn't mind hacking up or disassembling a few in order to build a nice stage like I'm seeing posted here on photomacrography. Using stages like that is a new idea to me. I probably have 150 to 200 objectives that are orphaned from their mommy-mics and just sitting in their individual cases strewn throughout various boxes.

As a first step I'd like to identify which are good for use on a DSLR body. I know what they look like (IQ, etc.) through a nice scope but in that arena things like WD and etc. aren't as critical. So I made an indexed click-page so that I could show them to you good folks here without plastering 50 images into my post. Here's that:

http://tesselator.gpmod.com/Microscope_Objectives/

Cell #1 shows the maker/serial side of the objectives and provides a size perspective of the various objectives. The individual objective images show the spec info side of them.

My bellows only extends to about 160mm and I was wondering if that's going to be a problem at all? What are the advantages of a longer bellows - sensor coverage & magnification or only magnification? What's the cheapest bellows (any mount)?

I'm also interested in discovering how much these are worth on the open used market. I have no idea so if you know about how much any one, several or all of these are worth please post it up! I'd like to start selling some of these off and I have no idea what to ask for them nor which one's I should keep for myself. If there's a few that you think are worthless junk don't be afraid to say so - I'm not emotionally attached to them or anything. On that note I included one that has fungus damage (Cell #23) so that you can see what that looks like under this lighting and at this particular camera angle.

Thanks! And if nothing else just have fun looking at the images. Feel free to journey into any topic area - it's all good!

[Charles Krebs]

Tesselator,

Quite a collection! I'll have more time to peruse these later today.

Certainly any Plan Apos (or Apos) might get a few bucks on eBay.

For bellows use (with opaque subjects) working distance will be a key issue. Typically you have a decent shot at usable working distances with a 4X or 10X (not guaranteed... some 10X have quite short WD). With 20X it would be rare to have enough WD with a "normal" objective, but sometimes it is barely possible. For 20X and higher the ones that can be useful are typically ones designed for longer than "normal" working distances, and are usually marked as such (LWD, ELWD or something like that). You have some infinity corrected ones, and these are not the ones you want for a bellows. (There is currently a fairly long thread going on about these). You have several 100X. These are really only useful on a compound microscope, and unless they a "special" in some way (Plan Apo) don't usually fetch much when sold.

Then, when you isolate the ones with usable working distances you will need to "test" to find the ones with the least amount of chromatic aberration. From a cursory look, nearly all of these are from systems where, by design, final chromatic corrections were made in an eyepiece. When used alone on a bellows the uncorrected aberrations can really be an issue (while sometimes they are not too bad at all). Have to try them to find out.

[Tesselator]

Tesselator,

Quite a collection! I'll have more time to peruse these later today.

That would be quite awesome! Thanks!

Certainly any Plan Apos (or Apos) might get a few bucks on eBay.

Yeah, I'd like to fund a good camera body purchase. I sold my D2x a few years back to pay for a friends' medical bills and haven't really replaced it yet. I keep waiting for the right combination of sensor and features. Sony is getting close to filling the bill tho.

For bellows use (with opaque subjects) working distance will be a key issue.

But the bellows length is not much of an issue? 160mm is OK? Here's the bellows on one of my film cameras:

Typically you have a decent shot at usable working distances with a 4X or 10X (not guaranteed... some 10X have quite short WD). With 20X is rare you'll have enough WD with a "normal" objective, but sometimes is barely possible. For 20X and higher the ones that can be useful are typically ones designed for longer than "normal" working distances, and are usually marked as such (LWD, ELWD or something like that). You have some infinity corrected ones, and these are not the ones you want for a bellows. (There currently a fairly long thread going on about these). You have several 100X. These are really only useful on a compound microscope, and unless they a "special" in some way (Plan Apo) don't usually fetch much when sold.

Yeah, with powers of 50 and lower I can tell the WD by looking through the objective directly with my eye - I think. Some of them (even at 40x) have like a one or two CM focus point while others (even one of the 10s and one of the 4s) are like 1mm or 2mm. Is this assumption correct or is what I'm seeing unrelated?

Then, when you isolate the ones with usable working distances you will need to "test" to find the ones with the least amount of chromatic aberration. From a cursory look, nearly all of these are from systems where, by design, final chromatic corrections were made in an eyepiece. When used alone on a bellows the uncorrected aberrations can really be an issue (while sometimes they are not too bad at all). Have to try them to find out.

Yup, there are a few like that but not too many. I've put almost all of these on one of my straight scopes with various normal eyepieces to check quality, dirt, CA, and fungus. There were a few of the smaller Olympus 40's and more than half of the 100's that had noticeable CA which would ruin a photo at anything above 33% scale. Most were surprisingly good and of course the APO's were.. umm, well, apochromatic! YAY!


Thanks for all the info and comments! Very appreciated!!!

[rjlittlefield]

But the bellows length is not much of an issue? 160mm is OK?

That would be fine. Your 160/ objectives are designed to create their image 150 mm from the shoulder of the mounting threads. But at low NA (0.30 and below), you can change that distance quite a lot without degrading the image.

Yeah, with powers of 50 and lower I can tell the WD by looking through the objective directly with my eye - I think. Some of them (even at 40x) have like a one or two CM focus point while others (even one of the 10s and one of the 4s) are like 1mm or 2mm. Is this assumption correct or is what I'm seeing unrelated?

Your assumption is correct. The working distance when photographing will be almost exactly the same as the working distance when holding the objective close in front of your eye and using it as a magnifying glass. If you have a 40X objective that gives 1 cm working distance and makes a good image, hang onto it!

--Rik

[Tesselator]

Awesome info bro! Thanks!

[Charles Krebs]

I've looked over the pictures and "recognize" some of these. Probably the best quality (and most salable) are some of the Nikon ones in the first 10 images. You can find a few of these (the Fluor models) in this pdf:
www.krebsmicro.com/Nikon_CF.pdf

I'm pretty sure the Plan Apos (picture #4 and #5) are the first "CF" models (prior to the ones in the brochure above). I can't be 100% sure because Nikon didn't mark all the CF objectives, and these were before my "time" in microscopy. Objective brochures from that era are not commonly found (at least by me . ). I'd love to get a copy of the first "CF" objectives brochure. The one given above is mostly for the second generation of Nikon's CF biological objectives.

So the 10/0.4 Plan Apo could be great on a bellows, but my suspicion is that the working distance will be very small (typical of most PA's above 4X). And depth-of-field would be astonishingly shallow.

The older Nikon objectives with an "s" above their engravings were from their "S" series stands (60's vintage). These used corrective eyepieces.

Two other older ones that I have a little info on are the 1.2/0.03 Plan and the 40/0.65 NCG (no cover glass). The 1.2X has a focal length of 35.8mm and a working distance of 29.7mm. The numerical aperture is low, so you would likely get better results with most any decent macro lens. The 40/0.65 NCG is interesting in that you don't see to many 40X biological objectives designed for no cover. It has a working distance of 1.3mm. Too small really to be of use (Nikon made 40X CF M Plans with working distances of 3, 10.1 and 14.9mm... far more useful on a bellows). But it might be interesting to try and squeeze a little light in past that 1.3mm and try it since it's just sitting there!

[OzRay]

Charles

Someone will have to bottle your blood, it's got to be worth more than gold.

Cheers

Ray

[Tesselator]

I've looked over the pictures and "recognize" some of these. Probably the best quality (and most salable) are some of the Nikon ones in the first 10 images. You can find a few of these (the Fluor models) in this pdf:
www.krebsmicro.com/Nikon_CF.pdf

I'm pretty sure the Plan Apos (picture #4 and #5) are the first "CF" models (prior to the ones in the brochure above). I can't be 100% sure because Nikon didn't mark all the CF objectives, and these were before my "time" in microscopy. Objective brochures from that era are not commonly found (at least by me . ). I'd love to get a copy of the first "CF" objectives brochure. The one given above is mostly for the second generation of Nikon's CF biological objectives.

So the 10/0.4 Plan Apo could be great on a bellows, but my suspicion is that the working distance will be very small (typical of most PA's above 4X). And depth-of-field would be astonishingly shallow.

Yeah, #3 ~ #11 are all short WD objectives. The WD of #5 is about 3mm which is the longest of that set (<#12). #4, and #5 are exceptionally bright and clear with what seems to me to be an incredibly deep DOF for a mic. objective. Maybe a whole millimeter or so. #3 and #7 (and 8 and 6 too) are almost as bright and clear but DOF is so small I would probably have to stack hundreds of images to get a decent result on something the thickness of a dime.

The older Nikon objectives with an "s" above their engravings were from their "S" series stands (60's vintage). These used corrective eyepieces.

Two other older ones that I have a little info on are the 1.2/0.03 Plan and the 40/0.65 NCG (no cover glass). The 1.2X has a focal length of 35.8mm and a working distance of 29.7mm. The numerical aperture is low, so you would likely get better results with most any decent macro lens.

Ah, good to know. That's one of the markings I didn't know. I had been using these for idents which doesn't list the "s":



http://micro.magnet.fsu.edu/primer/anat ... tions.html

The 40/0.65 NCG is interesting in that you don't see to many 40X biological objectives designed for no cover. It has a working distance of 1.3mm. Too small really to be of use (Nikon made 40X CF M Plans with working distances of 3, 10.1 and 14.9mm... far more useful on a bellows). But it might be interesting to try and squeeze a little light in past that 1.3mm and try it since it's just sitting there!

Yup. I think that hemispherical ping-pong ball idea with some BRIGHT white LEDs would probably fit the bill for that. And if nothing else I can just put it on my Eclipse 80i and use it normally. The only trouble with that is that I don't have the optional digitizer for it and neither a DSLR adaptor, so I'm having to use a point & shoot straight up through an eye-piece. That's fantastic for single images but for stacking it can be a pretty huge pain. :p


One interesting note: #22 seems to be the same objective as shown in the e-bay auction of that $33,000 universal stage. See his fifth image. I think I have the others in that set (in his image) as well but in another box somewhere. I'll have to have a look.

Also on page 2, #18 there's a Nikon I can't figure out what "BM" stands for. Do you have any idea?

Some great info here man! I really appreciate it! I'm starting to have a pretty good understanding of what's desirable and what will present some problems.

[PauloM]

BM might refer to a type of phase contrast objective, same as DL and DLL.
Take a look at this article:

BM (Bright Medium - High Negative Contrast) - Often referred to as negative phase contrast, BM objectives produce a bright image outline on a medium gray background. BM objectives are ideal for visual examination of bacterial flagella, fibrin bundles, minute globules, and for blood cell counting.

Take a look at the back of the objective and see if you spot a phase ring of some sort. I suppose might look different from the usual DL phase rings, but it should be recognizable nevertheless.

#44 is not really an objective. It's an accessory for centering a fluorescence illuminator's lamp. You're supposed to attach it to a nosepiece in place of an objective, and adjust the lamp house's centering screws until a bright green crosshair is superimposed on the crosshair that's printed on the accessory. Don't know if it would be useful to center visible-light epi-illuminators as well.

P

[Tesselator]

BM might refer to a type of phase contrast objective, same as DL and DLL.
Take a look at this article:

BM (Bright Medium - High Negative Contrast) - Often referred to as negative phase contrast, BM objectives produce a bright image outline on a medium gray background. BM objectives are ideal for visual examination of bacterial flagella, fibrin bundles, minute globules, and for blood cell counting.

Take a look at the back of the objective and see if you spot a phase ring of some sort. I suppose might look different from the usual DL phase rings, but it should be recognizable nevertheless.

Excellent thinking! And yup, sure enough, there it is:



Looks just like DLL or DL to me though.

#44 is not really an objective. It's an accessory for centering a fluorescence illuminator's lamp. You're supposed to attach it to a nosepiece in place of an objective, and adjust the lamp house's centering screws until a bright green crosshair is superimposed on the crosshair that's printed on the accessory. Don't know if it would be useful to center visible-light epi-illuminators as well.

Hey, I knew that! And yeah, I've stuck it on a phase contrast rig before and it's a little helpful for centering if using the iris wide open. Stopped down there's little difference.. maybe efficiency or something.


Thanks mate! Very appreciated!

[Cactusdave]

An enviable collection of objectives. If they are only a fraction of your total collection, and the rest is of equal quality, then I don't think that you will need to part with too many to fund even a top DSLR . I have sent you a PM about a couple of the objectives.

[Tesselator]

An enviable collection of objectives. If they are only a fraction of your total collection, and the rest is of equal quality, then I don't think that you will need to part with too many to fund even a top DSLR . I have sent you a PM about a couple of the objectives.

Thanks man! Don't expect me to know what I'm talking about though.

As stated I have no idea what any of these go for nor how much variance in price there is from model to model and type to type.