Wanted: 0.5 Barlow lens for AO 569 stereoscope
Wanted: 0.5 Barlow lens for AO 569 stereoscope
Hi all, I’m looking for an 0.5 Barlow lens for my American Optical 569 Starzoom 0.7-3 scope.
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
There are 2 of those. Cat.# 575 will be marked on the barrel of one of them. It is quite long compared to all the other aux. lenses, almost 2". It has a 5.7" working distance.
The other one is a special order .5X with an 8" working distance. The cat. # is K2595. K numbers were usually reserved for special purpose accessories and are not often marked on the part, probably because there were no blanks made up. The # would have had to have been hand stamped. Not a good idea on a lens housing.It is shorter, maybe about 11/16" deep and resembles the .3X but the .3X will be marked as such with #573 additionally.
There are also many more Cycloptic aux. lenses out there and they superficially resemble those for the Stereostars. Most are marked with a catalogue number but a few are not. The Cycloptic lenses have a smaller thread, 1 13/16" diameter.
The Stereostar thread is 1 7/8", which is very close to 48mm, about 1/3mm short. 48mm is a kind of standard size for stereo aux.lenses. I rechecked the stereostar thread and I can run a 36 t.p.i. gauge around the perimeter. Neither a 32 t.p.i. or M .75 will, so I would say it is 1 7/8" X 36 t.p.i.. However, in a pinch the M48 X .75 .5X lens could probably be made to thread on enough to work, so depending if you can find an AO one, those Chinese ones aren't expensive.
Anyone tried one of those?
The other one is a special order .5X with an 8" working distance. The cat. # is K2595. K numbers were usually reserved for special purpose accessories and are not often marked on the part, probably because there were no blanks made up. The # would have had to have been hand stamped. Not a good idea on a lens housing.It is shorter, maybe about 11/16" deep and resembles the .3X but the .3X will be marked as such with #573 additionally.
There are also many more Cycloptic aux. lenses out there and they superficially resemble those for the Stereostars. Most are marked with a catalogue number but a few are not. The Cycloptic lenses have a smaller thread, 1 13/16" diameter.
The Stereostar thread is 1 7/8", which is very close to 48mm, about 1/3mm short. 48mm is a kind of standard size for stereo aux.lenses. I rechecked the stereostar thread and I can run a 36 t.p.i. gauge around the perimeter. Neither a 32 t.p.i. or M .75 will, so I would say it is 1 7/8" X 36 t.p.i.. However, in a pinch the M48 X .75 .5X lens could probably be made to thread on enough to work, so depending if you can find an AO one, those Chinese ones aren't expensive.
Anyone tried one of those?
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
I ran some numbers and 36tpi seems to be a close match for 0.7mm pitch (36TPI = 0.706mm), which is probably close to tolerance. M48 as you mentioned looks to be a tolerable match for 1-7/8", but I don't expect much likelihood of finding a compatible lens threaded for M48 with a 0.7mm pitch. I don't think 0.7mm pitch is used much outside some of the small metric bolts.apochronaut wrote: ↑Thu Jul 08, 2021 2:35 pmThe Stereostar thread is 1 7/8", which is very close to 48mm, about 1/3mm short. 48mm is a kind of standard size for stereo aux.lenses. I rechecked the stereostar thread and I can run a 36 t.p.i. gauge around the perimeter. Neither a 32 t.p.i. or M .75 will, so I would say it is 1 7/8" X 36 t.p.i.. However, in a pinch the M48 X .75 .5X lens could probably be made to thread on enough to work, so depending if you can find an AO one, those Chinese ones aren't expensive.
Anyone tried one of those?
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
0.75mm would be standard for optics though not universal. I've had instances where 0.75 mm threaded fine into 0.70 MM, and instances where they did not.
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
0.75mm pitch correlates pretty close to 34tpi (34tpi = 0.747mm / 0.75mm = 33.87tpi) (apologies if this is just noise).Scarodactyl wrote: ↑Thu Jul 08, 2021 5:44 pm0.75mm would be standard for optics though not universal. I've had instances where 0.75 mm threaded fine into 0.70 MM, and instances where they did not.
If one could find a compatible lens and has access to, or friends with, machining equipment (3D printer, possibly?), it shouldn't be a difficult task to create a mount/holder/barrel for it. The effort required may well exceed the value, but different people have different measures of what's reasonable. I've had poor luck making fine threads with 3D printing, but I have had reasonable luck making tight interference fits and using the threads to "cut" into and hold onto the plastic; it usually involves some sanding and fitting of the 3D printed part. I have a holder for a Cycloptic 2x barlow that works that way.
I'm certainly not suggesting this as a good option, but if one can't find the correct part and really wants the functionality badly enough it may be a solution.
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
I have gotten threads down to 0.5mm pitch to work with 3d printing (for a Nikon trinoc head). They jst have to be dialled in, and internal threads have to be oversized a bit since they print tight.
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Interesting. Do you print your own 3D stuff, or do you commission somebody else to do it? On another front, if you're still interested in selling that rusted 577s lens you have, I'm interested.Scarodactyl wrote: ↑Thu Jul 08, 2021 8:31 pmI have gotten threads down to 0.5mm pitch to work with 3d printing (for a Nikon trinoc head). They jst have to be dialled in, and internal threads have to be oversized a bit since they print tight.
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
I won't sell it but I'd send it for the cost of shipping, probably like 5 bucks. Some cleanup, knock out the corroded lenses and it should be good to go. Shoot me a pm with a paypal address.
I print them myself on my ender 5.
I print them myself on my ender 5.
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
If you use a barlow. You can clamp your ringlight directly onto that but obviously will need the 577 blank otherwise.
There are two incarnations of the M48X .75 barlows available.
https://www.ebay.com/itm/273469486556?_ ... %3A2047675
This one has a slightly longer W.D. but both are over 6" This appears to be the same one Amscope sells at twice the price and oddly gives a thread diameter of both
1 7/8" as well as 48mm. Running a .75 mm thread gauge into the female thread of a 570 , the gauge started to bind about 1/3 of the way around. With the extra leverage provided by the lens housing it will probably go on 1/2 turn or a little more, so about 1/2 way to lock. A lens with the correct thread turns 1 1/3 turns to lock.
https://www.ebay.com/itm/274333279910?_ ... %3A2334524
There are two incarnations of the M48X .75 barlows available.
https://www.ebay.com/itm/273469486556?_ ... %3A2047675
This one has a slightly longer W.D. but both are over 6" This appears to be the same one Amscope sells at twice the price and oddly gives a thread diameter of both
1 7/8" as well as 48mm. Running a .75 mm thread gauge into the female thread of a 570 , the gauge started to bind about 1/3 of the way around. With the extra leverage provided by the lens housing it will probably go on 1/2 turn or a little more, so about 1/2 way to lock. A lens with the correct thread turns 1 1/3 turns to lock.
https://www.ebay.com/itm/274333279910?_ ... %3A2334524
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Just did a test on a bad 569 I forgot I had. An olympus 48mm 0.5x doesnt quite thread on, but a 48mm plastic ring light adapter that came with a ring light did thread on with a little effort. That would probably be much better than having to modify the broken auxiliary lens ane I can send it for the same price.
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Scarodactyl, I had bought a ring light with a plastic 48mm ring, that kept popping off when I tried to screw it in place. But I hadn’t tried to wrestle it into place until I read your last post. I was worried about damaging my scope. But having heard that you used “a little effort” to attach what sounds like a similar adaptor, I tried a bit harder and was able to get it on far enough to stay in place and hold my ring light! If I pull on it with any force, it pops off, but it’s firm enough to hold the ring light.
Thank you all for your suggestions. I’ll try to take a picture and post it.
Thank you all for your suggestions. I’ll try to take a picture and post it.
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Here are some pics
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Excwllent, I'm glad that worked!
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Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
That's a good start. How does the .5X barlow fit into the picture?
Re: Wanted: 0.5 Barlow lens for AO 569 stereoscope
Oops. I posted that in the wrong thread. Nothing to do with the Barlow. My bad.apochronaut wrote: ↑Fri Jul 09, 2021 2:02 amThat's a good start. How does the .5X barlow fit into the picture?