Reichert Stereo Star 580 vs B&L Stereozoom 7 vs Nikon SMZ-U vs Olympus SZH vs Leica M80

[einman]

I could have included a Zeiss SR but the original eyepieces, although functional, have a fungus on the lenses. So I currently use Nikon 10x/26.5 eyepieces. Given they are not the original eyepieces I did not include it.

[einman]

I enjoy reading your spots, thank you einman!

Isn't apparent DOF affected by perceived contrast? One would think resolution/NA determines DOF for the same optical design. But then, those scopes probably do not have the same optical design.

I agree that resolution is not that important for dissecting scopes. They are used for their long WD and sample preparation mainly, at least in my hands. Critical high resolution examination or focus stacking is always best left for compound scopes.

You made a good point about providing good strong lighting. Even though NA 0.1 sounds about good enough for 40x total visual magnification, all those scopes herein go up to 60x or more (so they need better light at higher magnification). After reading your posts, I can remember this now; it was indeed at around 50-60x, where I saw image degradation, from my SZ7. 30x and below did look pretty good.

Actually the NA is measured at the highest zoom factor. So as you increase the zoom magnification the NA increases. It is the change in the DOF etc that results in apparent image degradation.

I chose 40X because that is generally the highest magnification of generic stereoscopes although by so doing I may be limiting a given scope depending on its design. It is the intent of my study to get an idea of what you can purchase in terms of performance and not so much proving the technical superiority of one scope over another. That is just way too much to do and is in part why I got bogged down.

[MichaelG.]

Maybe a bit out of left field, but is there a correlation of alphabet letters to features in the designations such as 'SMZ', 'SZH', etc.?

I may be wrong [and I'm very happy to be corrected], but I think the usage of the letters is fairly consistent:
S = Stereo
M = Microscope
Z = Zoom
H = High performance

MichaelG.

[apochronaut]

[quote="einman"]I used a digital caliper and repeated my measurements for the 5th time. I get 20 mm for the cat 31-15-75 15x UWF eyepieces at 1.0x. They coincidentally match Leica's technical specifications which gives me more confidence in my results. Would you like a copy? You have not commented at all on the fact my data is supported by Leica. Here is a pic I just did. This time I marked the lines at the widest section of the FOV. I then measured the marks. A slightly different method but with the same results.

[/quote

Sure, send me the specs from Leica....and a picture of the eyepiece. Maybe we are talking about different eyepieces. I am talking about the Bausch & Lomb U.W.F. 15X. The cat. # you are quoting is a B & L #. and I am pretty sure that I have seen them with Leica branding but usually Leica used entirely different #'s for older parts from B & L, Reichert etc. Perhaps they were changed for some reason by the time Leica came on the scene, I don't know. What I do know, is that the field with the Bausch & Lomb examples I have ( 2 sets and one branded FJW), when viewed with a 1 x objective at 15X total magnification is 22mm across when actually measured on the stage . At 10X it is 29.5 , so the field coverage when compared to the standard 20mm field covered by a 10X eyepiece is almost 50% more at 10X and even with a 50% bump in magnification, it is still 10% greater. ...and they don't cost an arm and a leg, to acquire a set.

Your method of measuring is a bit cumbersome. Why don't you just put a metric ruler or scale on the stage and see what field the eyepieces actually provide? If you don't have a a small metric scale the imperial equivalent is very close to 25/32" for 20mm and just a hair under 7/8" for 22mm.

The nice thing about the B & L 15X U.W.F., is that when they show up at low prices, which they do, one can utilize them on any B & L stereozoom 3,4,5, 7 ..doesn't matter or an AO stereostar to get a really W.F. instrument. It's pretty surprising performance for 1970's technology. The whole microscope could be as low as 250.00 and up to 550.00 or so and you would be getting a field that you would normally have to invest over 1000.00 to acquire, likely a lot more. It is almost impossible to find a Nikon SMZ-U or Olympus SZH for under 1000.00 used, so those B & L U.W.F. eyepieces offer a nice way of putting together a nice U.W.F. microscope for low cost.

I'm still curious about the 14mm measurement you got for the 31-05-68? Doesn't that seem rather low?

[MichaelG.]

Regarding field-of-view comparisons ...

As mentioned in a previous thread:
viewtopic.php?p=48592#p48592
I find it convenient to print a set of concentric circles.
The sample uses 5mm increments of diameter; which will usually suffice for StereoMicroscopes.

MichaelG.

[PeteM]

Reason I asked is about your goal for the comparison is because I'm gradually putting a guide together on relatively affordable compound and stereo microscopes for parents and kids.

So far, I just have photos and notes from 100+ microscopes so far fixed. up. Like you, it may take a while. I've tried to get multiple examples of used scopes that seemed good candidates - typically just one of a few newer scopes - and have so-far donated around 70+ to a kids program, our library, etc.

At some point I hope some of the many experienced users here, like yourself, will be willing to add their own experience.

Seems to me, especially when places like Ebay are the main source, that availability and price is another important criterion you might want to consider?? For example, of the four B&L Stereozoom 7 I bought, all had defects or undisclosed missing parts. I was able to cobble together one good one. Most troublesome were the two likely used for years of soldering -- the bottom lenses were so hazed that all contrast was lost.

You're right that it's a fine instrument if you find a great example. My limited experience is that those fine examples are hard to come by. They 7x zoom part (pretty amazing) is also mechanically very complex and with small aperture lenses. I'm willing to tear into things like trinocular heads with loose prisms and most misaligned stereo microscopes -- but that one B&L 7 that stalled midway through the zoom, once opened up, looked pretty daunting to me.

Anyhow, others' experience on common problems and their resolution might be something to add?? For example, Apochromat's point in an earlier thread about the Reichert 410/420 having a common problem -- but also easily fixed -- to yield a great value in an infinity microscope seems worth passing on. There is a similar common but easily fixed problem (fine focus gear) with the otherwise excellent Nikon Labophot.

Anyhow -- looking forward to your evaluation. The stereo scopes I'm finding comfortable to use, in generally decent or repairable shape, widely available, and reasonably priced for parents include the Olympus SZ (3 etc.), the B&L StereoZooms from 2 to 4, the Nikon SMZ-2, the AO Cycloptics, most anything Meiji, and the AO 570/580 that you're also including in your evaluation. So far a lot of the Olympus need alignment but are otherwise very good and the Cycloptics often need prisms re-glued and subsequent alignment. Once that's done they've tended to be fine.

[apochronaut]

Regarding field-of-view comparisons ...

As mentioned in a previous thread:
viewtopic.php?p=48592#p48592
I find it convenient to print a set of concentric circles.
The sample uses 5mm increments of diameter; which will usually suffice for StereoMicroscopes.

MichaelG.

Yes, those are good. and concentric circles are quite useful for assessing spherical distortions ; the beginning point and extent. for instance. However, in lieu of that being available this is a simple matter of looking through the eyepieces at a ruler along the mid line of the field, set to one edge of the field and seeing what the measurement is on the other side. The numbers on the scale can't be wrong.

I had a subsequent thought regarding my questioning of the 14mm f.o.v. for a 15X eyepiece with a 1X objective( 15X). It seems more in line with the field of a 20X eyepiece. Testing, the 20X cat. # 31-05-63 eyepiece; the one catalogued for all the B & L stereo and stereozoom pods, I get exactly that, 14mm with a 1X objective( 20X)

[einman]

"Your method of measuring is a bit cumbersome. Why don't you just put a metric ruler or scale on the stage and see what field the eyepieces actually provide?" Actually that is how I did the measurement initially!! The pic I posted was a quick re-check using "another" method as I believe I mentioned.

Sorry I have been traveling and have not been on the forum for a while. Hey Phil I hope to get up your way sometime this year. Perhaps we can get together. I will let you know.

[apochronaut]

Why sure. The farm house goes into reno., this summer, so bring your tick repellant and a plastering trowel. However, if you stay close to town, bring a tourist repellant.

[einman]

Why sure. The farm house goes into reno., this summer, so bring your tick repellant and a plastering trowel. However, if you stay close to town, bring a tourist repellant.

LOL. I have some strong tick repellant. No experience with plastering but can learn. Glad to see the farm house is getting renovated! I will keep in touch. The wife has been wanting to go to Canada for a while now.