Advice on buying Stereo Microscope

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PeteM
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Re: Advice on buying Stereo Microscope

#31 Post by PeteM » Fri Mar 26, 2021 6:58 am

dazz wrote:
Fri Mar 26, 2021 2:58 am
Hi
I found this post because I am searching for advice on buying a stereo microscope for use with electronics. . . .

Dazz
Here's one set of opinions you might find helpful: https://engraverscafe.com/threads/stere ... void.3451/

I've had a Kyowa scope and thought it was well built. Not sure, though, about a supplemental objective for it to get the lower magnification and greater working distance you might want for soldering and electronic work.

Leica quality tapered off for a while and I think the $599 Leica SZ4 scope you listed might have been built about that time. It might be of lower quality than its B&L precursors. Others will likely know. It seems overpriced to me - but does have about the right magnification range for most electronics work.

Some of the older (and more affordable) Nikon and Olympus scopes have a zoom range from 7 or 8x to 30 or 40x and a 21- 23mm field of view. Those should work if you find one priced right.

Seems to me the ideal would be a scope on a boom stand, so that's another consideration. Some people need to document their work - so a trinocular head is another question.

I've had a couple Chinese zoom scopes priced new under $500. One had a broke zoom gear. The other had its zoom magnification wander a bit in the range. Still, I think one that performed OK out of the box (test it for alignment and zoom parfocality) would usable and last for quite a while given reasonable care.

dazz
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Re: Advice on buying Stereo Microscope

#32 Post by dazz » Fri Mar 26, 2021 8:46 am

PeteM wrote:
Fri Mar 26, 2021 6:58 am

Here's one set of opinions you might find helpful: https://engraverscafe.com/threads/stere ... void.3451/
Thanks for the link. It makes a good read. Most of the brands mentioned (good or bad) I have never seen for sale in New Zealand.
PeteM wrote:
Fri Mar 26, 2021 6:58 am

I've had a Kyowa scope and thought it was well built. Not sure, though, about a supplemental objective for it to get the lower magnification and greater working distance you might want for soldering and electronic work.
The high auction price of the Kyowa scopes selling here are an indication of how thin the market is here.
PeteM wrote:
Fri Mar 26, 2021 6:58 am
Leica quality tapered off for a while and I think the $599 Leica SZ4 scope you listed might have been built about that time. It might be of lower quality than its B&L precursors. Others will likely know. It seems overpriced to me - but does have about the right magnification range for most electronics work.

Some of the older (and more affordable) Nikon and Olympus scopes have a zoom range from 7 or 8x to 30 or 40x and a 21- 23mm field of view. Those should work if you find one priced right.
I could be looking for a long time.
PeteM wrote:
Fri Mar 26, 2021 6:58 am
Seems to me the ideal would be a scope on a boom stand, so that's another consideration. Some people need to document their work - so a trinocular head is another question.
I only make/work on small electronic boards (phone sized but not phones).
PeteM wrote:
Fri Mar 26, 2021 6:58 am
I've had a couple Chinese zoom scopes priced new under $500. One had a broke zoom gear. The other had its zoom magnification wander a bit in the range. Still, I think one that performed OK out of the box (test it for alignment and zoom parfocality) would usable and last for quite a while given reasonable care.
My preference is to buy good used rather than new crap. I buy a lot of stuff from Aliexpress but buying a microscope would be the option of last resort.

Stomias
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Re: Advice on buying Stereo Microscope

#33 Post by Stomias » Fri Mar 26, 2021 1:10 pm

Bought one of these for $90. https://photos.app.goo.gl/2cMWjwm9yEagkpoH9 Had 10x eyepieces and 1x and 2x objectives. Found a 3x objective for it for $25. The objective actually came with another AO 25 body and 6 eyepieces (20x and 15X) I have since bought 5X and 20x eyepieces. I now have 5X-60X magnifications. Bought a Battery powered LED ring light for below the subject and a couple of different lights for above the subject. All in for WAY under $300 with excellent optical quality. 50 year old AO Spencer. Optics great, built like a tank. Note the 20x eyepieces are seldom used, I'd imagine you knpw why :)

dtsh
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Re: Advice on buying Stereo Microscope

#34 Post by dtsh » Fri Mar 26, 2021 6:00 pm

Frequently more expensive than what Stomias mentioned are the AO Cycloptics. If you're patient you can pick them up for around $100 (give or take $25).

Cycloptic reference manual: https://user.xmission.com/~psneeley/Per ... Manual.pdf


There are tons of nice used stereos if you're willing to hunt through the junk and read up on the models you find. Many of them are very good and for the money, one would need to spend a lot more to get better.

PeteM
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Re: Advice on buying Stereo Microscope

#35 Post by PeteM » Fri Mar 26, 2021 6:36 pm

The AO Cycloptics were (are) wonderful scopes for their time. Be sure, though, that the prisms in the head aren't loose or misaligned. They're often loose or poorly glued back in place - and very time consuming to repair without the original factory alignment tools.

Most electronics people I know prefer a zoom, with as wide a field as possible. The step-type microscopes like the Cycloptic and Wild M3 and M5 can provide wonderful images, though.

dazz
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Re: Advice on buying Stereo Microscope

#36 Post by dazz » Wed Mar 31, 2021 3:21 am

Hi
I see there a lot of micro-scope heads without bases on e-bay. I am looking at B&L Stereo Zoom 4 because they seem to be plentiful on e-bay and reasonably priced. Buying a head only appealing to me because the cost of shipping a base is likely to exceed the cost of me making a base. I have the tools needed to make a base.

The thing I don't know is why there are so many heads for sale? Is it because the heads are worn out and replaced with new heads?



Dazz

BramHuntingNematodes
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Re: Advice on buying Stereo Microscope

#37 Post by BramHuntingNematodes » Wed Mar 31, 2021 4:47 am

The classic B&L SZ4 is perhaps the most rugged and durable of any microscope I have handled, and that includes their shop scope which was designed to be dropped. I have seen some broken ones and some with chemical etched optics but mostly just dinged and dirty. There were many custom inspection rigs used in industry that had heads mounted on larger pieces of machinery. Several older microtomes also had a stereozoom pod attached to monitor sectioning. There are also many stands and frames that get sold by themselves as well, although pricing suggests they are less common generally. Making a stand shouldn't pose too much of a problem. The focus mount is not exceptional save for its ruggedness, again. The outline of the heads is not circular, but a sort of squarish shape.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

PeteM
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Re: Advice on buying Stereo Microscope

#38 Post by PeteM » Wed Mar 31, 2021 5:50 am

I'd suggest you look for a B&L focus block with a holder meant to be boom mounted. It is fairly light mostly cast aluminum and compact. It won't add much to the cost of shipping and is likely worth the additional cost vs. making that part and a focus block on your own. The stand to hold it - easy and appropriate to make.

I like the old B&L stereozooms -- they work well for our "Micronauts." However, I don't think the optics are quite as good as some of the contemporary or slightly newer Meiji, Nikon, and Olympus zoom scopes. The latter have somewhat wider fields of view and tend to use glass prisms rather than first surface mirrors to get the images up into the eyepieces - making cleaning a bit less risky. While most microscope heads are sealed, seals deteriorate and dust and industrial mists find a way in. The B&L SZ 7 does use prisms up top, but has so many small lenses to achieve its wide zoom ratio that many used in industrial environments have lost contrast.

BramHuntingNematodes
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Re: Advice on buying Stereo Microscope

#39 Post by BramHuntingNematodes » Wed Mar 31, 2021 6:10 am

The other thing about the SZ7 is that if it has the coaxial illuminator the polarizers in it have undoubtedly delaminated, putting a crinkly, hazy plastic-glass sandwich in both optical paths. The plastic lower lens mounts are also prone to breaking as they are under constant tension. Great scope after you've worked on it for month.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

dazz
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Re: Advice on buying Stereo Microscope

#40 Post by dazz » Fri Apr 02, 2021 9:10 pm

Hi
A boom mounted head would be an ideal choice for me.
Trying to identify a suitable microscope head that I can't inspect or return if faulty is a gamble, especially from e-bay.
The cost of shipping will be the same regardless of the value of the microscope. Shipping cost is dead money.

As time goes by, I am learning more about microscopes. I think I will continue to watch and learn before diving in.
I think I need to find a reliable e-bay dealer.

Dazz

dtsh
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Re: Advice on buying Stereo Microscope

#41 Post by dtsh » Fri Apr 02, 2021 10:44 pm

dazz wrote:
Fri Apr 02, 2021 9:10 pm
Hi
A boom mounted head would be an ideal choice for me.
Trying to identify a suitable microscope head that I can't inspect or return if faulty is a gamble, especially from e-bay.
The cost of shipping will be the same regardless of the value of the microscope. Shipping cost is dead money.

As time goes by, I am learning more about microscopes. I think I will continue to watch and learn before diving in.
I think I need to find a reliable e-bay dealer.

Dazz
With eBay it's important to ask a lot of questions of the seller and to keep in mind that a "used" listing means in working condition, it doesn't mean "used, abused, and missing parts". If you buy a used item and it isn't in working condition the seller pays for return shipping by eBay policy as a non-working item is "non-working, for parts" and not used. When gambling on "deals" at eBay I think it pays to be a tinkerer too and to buy several to piece together the best bits, but not everyone likes to tinker.

I have had pretty good luck in the buy/sell subforum here. The chances that the person you are dealing with actually has a clue of the instrument's actual condition is much higher too. Price-wise my experience has been fair, I've gotten a microscope for less than the comparable in eBay and I've paid a little more than the average for another. I don't mind paying a bit more for what I want in good condition; sometimes one can save a little money cobbling, sometimes not.

dazz
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Re: Advice on buying Stereo Microscope

#42 Post by dazz » Sat Apr 03, 2021 6:37 am

dtsh wrote:
Fri Apr 02, 2021 10:44 pm


With eBay it's important to ask a lot of questions of the seller and to keep in mind that a "used" listing means in working condition, it doesn't mean "used, abused, and missing parts". If you buy a used item and it isn't in working condition the seller pays for return shipping by eBay policy as a non-working item is "non-working, for parts" and not used. When gambling on "deals" at eBay I think it pays to be a tinkerer too and to buy several to piece together the best bits, but not everyone likes to tinker.

I have had pretty good luck in the buy/sell subforum here. The chances that the person you are dealing with actually has a clue of the instrument's actual condition is much higher too. Price-wise my experience has been fair, I've gotten a microscope for less than the comparable in eBay and I've paid a little more than the average for another. I don't mind paying a bit more for what I want in good condition; sometimes one can save a little money cobbling, sometimes not.
Hi
e-bay is the option of last resort for me. A lot of traders won't ship out of the USA or even accept foreign payment. e-bay is absolutely awful. A few years ago, e-bay tried to establish a New Zealand business but couldn't even scratch the local on-line auction site trademe.co.nz. If you go to e-bay.co.nz, there are no local listings. Unfortunately the local market for stereo microscopes is severely constrained so I am forced to look out of country.

I wasn't actually aware that this site has a buy/sell section so I will look there.

I used to work briefly in an optical workshop that repaired and collimated binoculars. I have some relevant skills and a reasonably well equiped workshop. I could have a go at tinkering with one or two.

Dazz

dazz
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Re: Advice on buying Stereo Microscope

#43 Post by dazz » Thu Apr 15, 2021 11:10 pm

Hi
I am seeking opinions on this microscope https://www.ebay.com/itm/Wild-Heerbrugg ... 0667.m2042

It has the functionality I am looking for but I have never seen one of these first hand.
I can't inspect before buying.
I don't know what questions to ask the trader about this specific make/model of scope.
Does it look like it is complete?

The trader accepts offers, but I don't know what the ebay etiquette is for offers.

Any advice would be much appreciated.

Dazz

Scarodactyl
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Re: Advice on buying Stereo Microscope

#44 Post by Scarodactyl » Fri Apr 16, 2021 1:26 am

The m1 is an ultrabasic student scope. No way to change the magnification aside from changing thr main objective. I would not bother with one, if you want a long working distance microscope a nikon smz-1 or smz-2b will cost similarly and have better functionality, or you can spend a bit more ans get a Wild m7 which is even better.

dazz
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Re: Advice on buying Stereo Microscope

#45 Post by dazz » Fri Apr 16, 2021 1:49 am

Hi
That is the sort of advice that I would probably not be able to find by myself. Thanks for that.

A basic student scope is all I need for my application, but if I can get a better one for about the same price, I should do that.

Dazz

dazz
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Re: Advice on buying Stereo Microscope

#46 Post by dazz » Fri Apr 30, 2021 9:25 pm

Hi
I have been following e-bay for a while now and there are a steady stream of potentially suitable scopes but:
  • a lot of them look like they have had hard life
    some could have mold on the optics,
    many are missing eye pieces = more $$$ to find, buy and ship,
    many are missing a suitable bracket for a home built boom stand,
    the good ones are $$$$$$
    returning an item is not a practical option when buying outside the USA border.
Can anyone offer some advice on e-bay buying??

Dazz

BramHuntingNematodes
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Re: Advice on buying Stereo Microscope

#47 Post by BramHuntingNematodes » Fri Apr 30, 2021 9:30 pm

If you get am SZ7 I have a repair manual I can scan and send. They are not very hard to take apart but the alignment is sometimes out of whack and the manual has instructions on how to fix.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

dazz
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Re: Advice on buying Stereo Microscope

#48 Post by dazz » Sat May 01, 2021 1:29 am

BramHuntingNematodes wrote:
Fri Apr 30, 2021 9:30 pm
If you get am SZ7 ...
Brand?

Dazz

BramHuntingNematodes
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Re: Advice on buying Stereo Microscope

#49 Post by BramHuntingNematodes » Sat May 01, 2021 1:35 am

Bausch and Lomb or Leica. Don't.know know who else.makes a SZ7.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Greg Howald
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Re: Advice on buying Stereo Microscope

#50 Post by Greg Howald » Sat May 01, 2021 2:45 am

Well by now you know that asking advice draws great response. Everyone has an opinion. Sorting through it all must be quite the challenge.😃
Greg

dazz
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Re: Advice on buying Stereo Microscope

#51 Post by dazz » Sat May 01, 2021 5:51 am

Hi
The variation in recommendations indicates many solutions that would do the job.
I understand that a good Bausch and Lombe would be a good choice but I understand that it includes mirrors. So cleaning one risks scratching the mirrors.

Nikon, Wild, Leica and B&L have all been recommended. Finding one at the right price in the right condition in the right configuration is the challenge.

This one looks promising. https://www.ebay.com/itm/194078467177?s ... 1438.l2649
except no eyepieces.
The missing stand is a bonus. I don't want the heavy stand that normally comes with a boom because of the high cost of shipping.

Dazz

dazz
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Re: Advice on buying Stereo Microscope

#52 Post by dazz » Thu May 13, 2021 7:12 am

Hi
I have taken a stab at buying a B&L stereo zoom microscope on ebay https://www.ebay.com/itm/133750872535?s ... true&rt=nc

It is exactly what I am looking for in features.
It is complete with eye pieces and the boom mount.
The missing boom base is good because the cost of shipping this would be higher than the cost of making it.
It includes a Barlow lens so even if this is the wrong magnification, it should have acted as a lens protector.
I might be able to sell the Barlow lens if it is the wrong magnification.

I wouldn't say the price was a bargain but about half of what the many dealers on ebay would want. It is cheap enough to take the risk that the scope is only good for parts.
I have never seen a B&L SZ in my country. They are probably here but not put up for sale.

Now I just have to wait a couple of months for it to get from the USA to my country (cheapest and slowest service).
Dazz

Scarodactyl
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Re: Advice on buying Stereo Microscope

#53 Post by Scarodactyl » Thu May 13, 2021 7:26 am

That's a 0.3x auxiliary lens. It is rare and should be pretty sought after since it gives even greater working distance than the already-sought 0.5x.

dazz
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Re: Advice on buying Stereo Microscope

#54 Post by dazz » Thu May 13, 2021 8:05 am

Scarodactyl wrote:
Thu May 13, 2021 7:26 am
That's a 0.3x auxiliary lens ...
Hi
That is something to look forward to. A 0.3x will be perfect for my application.

Do the B&L aux lens have a thread on the bottom edge?
I have made microscope ring lights based on LED car angle lights https://www.aliexpress.com/item/3278977 ... 4c4dpFkDX5
I 3D print a suitable fitting and they work really well. No spots from the LEDs in the ring. An oversize ring seems to work best because it reduces reflections back into the lens.

If the B&L lens has a thread, I can attach the ring light to that.

Dazz

dazz
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Re: Advice on buying Stereo Microscope

#55 Post by dazz » Tue Sep 14, 2021 10:34 am

HI
After a 4 month wait for shipping, my B&L SZ4 has finally arrived. It looks like it has come out of a clean working environment and had an easy life.
First thing I am going to do is take it apart and clean it. That is what I always do when I get a new old item.
Next I need to make a base plate and an adapter to mount it on the computer monitor arm.
I also need to make a LED ring light.

Dazz

viktor j nilsson
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Re: Advice on buying Stereo Microscope

#56 Post by viktor j nilsson » Tue Sep 14, 2021 10:38 am

BramHuntingNematodes wrote:
Fri Apr 30, 2021 9:30 pm
If you get am SZ7 I have a repair manual I can scan and send. They are not very hard to take apart but the alignment is sometimes out of whack and the manual has instructions on how to fix.
Hadn't seen this before - I'd love to have that if it's not too much trouble!

BramHuntingNematodes
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Re: Advice on buying Stereo Microscope

#57 Post by BramHuntingNematodes » Tue Sep 14, 2021 6:15 pm

viktor j nilsson wrote:
Tue Sep 14, 2021 10:38 am
BramHuntingNematodes wrote:
Fri Apr 30, 2021 9:30 pm
If you get am SZ7 I have a repair manual I can scan and send. They are not very hard to take apart but the alignment is sometimes out of whack and the manual has instructions on how to fix.
Hadn't seen this before - I'd love to have that if it's not too much trouble!
I apologize for presenting this in the worst possible format I am having trouble with scanning.

https://imgur.com/a/Ov5adBc
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

PeteM
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Re: Advice on buying Stereo Microscope

#58 Post by PeteM » Wed Dec 22, 2021 4:19 am

Curious about the Wild M7a, today I plundered my budget and bought four of them. I'm pleased with the quality of this scope - and thought a report might be useful to others. There seems to be much more information about other Wild M series (M3, M3x, M3z, M5, M8 etc.) scopes available on various forums.

These were apparently last serviced decades ago, yet all but one came to me still aligned and with a smooth and parfocal zoom function. Perhaps a testament to their design and build quality.

One of the four had a sticky set of zoom elements. It would hesitate a bit after turning the zoom ring for the springs inside to pull the zoom elements parfocal. Opening it up was simple - three screws. Just taking a foam swab with a bit of oil and cleaning off the some sticky grease on the guide bars restored the zoom function.

The inside of these is beautifully precise and functional. For example, the zoom cam is machined out of brass and the balanced cam followers are ball bearings. I'd be surprised if any new scope under $10K is better built mechanically. The bottom line being, I think one of these could outlast a few Chinese zoom scopes with plastic gears and guides.

The zoom on these goes from 6x to 31x with 10x eyepieces. The 1x objective (fixed by three screws) is apparently plan achromat. It has better field flatness than a Wild M3 or a Nikon SMZ-10 as examples. I suspect that the difference between the M7 and M7a is a flatter-field objective as was done with the Nikon SMZ-10a superseding the otherwise excellent SMZ-10? Someone like jfresto or Scarodactyl might know?

A 6x low magnification is quite useful - much better to my mind than a scope whose lowest magnfication is 10x. 31x is more than most people need in a stereo microscope since 40x from a compound microscope might be the next step up. I tested both the Wild/Leica .5x and 2x clamp-on auxiliary lenses and they work fine. At the high end there is still useful magnification. The .5x reduction lens might be perfect for someone building a model or doing circuit board work. So a range from 3x to 62x is feasible.

The one minor puzzle in quickly testing was that the zoom on one of these (the previously balky one) tended to drift down on its own - with springs inside providing tension. Turns out there's a thumbscrew on the side to stiffen this up or even lock the zoom to a single focus. It could be -- and someone might inform me -- that greasing the large helicoid with a damping grease might also have been an OEM spec?

Comparing this scope to something like a Bauch & Lomb StereoZoom 4, the Wild M7a it is better made, avoids the use of hard-to-clean first surface mirrors, has a wider field of view, a slightly wider zoom range, and (to my eye) a better image. It should also be easier to maintain over the years. The B&L SZ4 is a very decent scope. This one is significantly better IMO.

Comparing this scope to something like the next step up Wild M8, it appears to accept the same heads, photo heads, irises etc. - but not the screw-in objectives. The M8 will have a still-wider zoom ratio, but also likely a significantly higher price tag. Mechanically, the M7a probably cost more than the M8 to build.

Comparing it to something like an Olympus SZ-4045, it seems optically about the same, but with a better build quality.

I also tested this with Chinese 10x/22 eyepieces machined to reach further into the tubes (beside the Wild Leica 10x/21b). They work fine, with an extra 1mm field of view without vignetting.

Bottom line - a very nice scope if you find one affordably priced. I'd prefer one of these in good shape to the $500 or so new Chinese zoom scopes I've seen so far.

Scarodactyl
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Re: Advice on buying Stereo Microscope

#59 Post by Scarodactyl » Wed Dec 22, 2021 6:13 am

The m7a really is a superb scope. I will probably pick one up as my personal stereo once I clear out some of the excess stuff I've piled up. The planarity and color correction are as you say a lot better than a normal achromat-equipped m3 and it just handles nicely. I suspect the smz10 was strongly inspired by the m7.

jfiresto
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Re: Advice on buying Stereo Microscope

#60 Post by jfiresto » Wed Dec 22, 2021 7:23 am

I am pretty sure the M7A is only semi-plan which is plan enough for me. The M7A/M7S brochure shows a modified identical plano convex pair to minimize spherical aberration:
wild_m7a_objective.jpg
wild_m7a_objective.jpg (29.76 KiB) Viewed 5336 times
You notice the objective's added flatness when you use an auxiliary lens, and am I starting to suspect, a photo tube: the 'tube seems to lose ambition outside the one-inch sensor area. The M7A has enough resolution to support 20X eyepieces without empty magnification, effectively doubling the maximum zoom vs. 10X, although not at a camera.

I understand that Leica/Wild had no problem selling the M7/M7A – its production spanned two generations and revisions of the M3/M3x – but the design had become too costly. Leica tried to outsource the model to Motic, but they were not quite up to it back then.
-John

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