Three odd surplus store finds

[Scarodactyl]

Hey everyone! I just got back from visiting relatives, and along the way we stopped in at a surplus equipment shop. I came across three lenses that looked like they might be fun, and figured I should ask if anyone might know anything about them and whether (and how) I should try to hook them up to a camera.

First up, I kind of assume this one is an industrial zoom inspection lens? It has what look to be two motors whose cords have been cut. I can turn one of them which controls the zoom. I assume the other one controlled vertical position for focus. So probably a standard c-mount zoom lens?




Next up is a fixed lens which is attached to a plate of some sort. I am not quite sure why it's arranged as it is, but it is marked Oriel--they make spectrometers, so maybe it's a part from one? Just looking through it it seems to magnify nicely.





Last, and maybe most intriguing, is this big 'ol thing. One side of the box said CRT lens, but the other side has this label:

"Perkin-Elmer
NTSC finite conjugate TV copy lens Prototype for CBS labs circa 1968; obtained from Bob Rhuel of EO mktng."\
It's really hefty, and both sides have a yellow filter of some sort. The filters have some scratches too, probably fine inside though. I am not quite sure what to do with it, but with how it was priced I couldn't leave it.

Anyway, I'd really appreciate any advice on these. They looked like fun anyway.

[genera]

The first piece looks like it has dovetails on both the x and y axes. Probably for some sort of distortion correction. I'd hang on to this but probably forget about it before I found a use for it. The threaded end looks like it might fit a C mount video camera as you've said. If you have a C mount camera hook it up and see what you get.

The black device marked Oriel 62020 on the second assembly is a filter holder for a stack of 2" diameter filters. It's sized to fit the 2" lenses on Oriel's UV and QTH lamphouses. Not necessarily how this piece was used though.

Where's this surplus store? There used to be a lot of great ones in the L.A. area but they're almost all gone or just a shadow of what they used to be.

[Lou Jost]

These kinds of finds are always exciting! How lucky to be able to physically search for hidden treasures, much more fun than eBay searches.

[AlxndrBrg]

no idea about the lenses, but the stepper motors are certainly usable for making an automated stacking rail, if they work that is.

[Scarodactyl]

The surplus store was P&E surplus in Kingston, NY. They had a fair number of microscopes in various states of assembly as well as bits and pieces scattered throughout--I also picked up a nice AO 570 stereoscope for my uncle at a very nice price. It is kind of a wonderland honestly, and I'd strongly recommend it if anyone here is ever in the area.

I'm not sure why I hadn't thought to just hook the first one up--I even have a c-mount to canon adapter already set up for my Wild makrozoom. I had a go at it, but it seems that I was wrong. Rather than zooming the knob seems to instead change the working distance (? maybe the wrong term) of the lens, ranging between significantly shorter than the metal lip that extends past the end of the lens to about 1 meter. Either way, the image quality in my bad test shot (greatly limited by the fact I was holding the whole thing freehand, and was also sitting down and didn't want to get up) is far from mind-blowing so I will probably as suggested just set that one aside for now. I have no idea what that would be for, and I'm definitely running against the limits of my very limited knowledge of optics. I also don't know if the motors are salvageable with the wires cut--I know very generally that kind of damage can range from a minor pain to total roaching.

Anyway, I will try to poke at the other two when I get the chance.

[ray_parkhurst]

The motor I can see appears to be a Vexta with dual-shaft. That's nice to have for manual movements. What is the model number? If it starts with a 5, its going to be tough to find a controller. If it starts with a 2 it might be useable with Stackshot/WeMacro/MJKZZ controller.

[Chris S.]

I also don't know if the motors are salvageable with the wires cut--I know very generally that kind of damage can range from a minor pain to total roaching.

The motor I can see appears to be a Vexta with dual-shaft. . . . What is the model number? If it starts with a 5, its going to be tough to find a controller. If it starts with a 2 it might be usable with Stackshot/WeMacro/MJKZZ controller.

I also winced at how closely the wires had been cut. Why didn’t whoever cut them leave more room for salvage?

This said—and having no argument with Lou that the motor might be a dual-shaft Vexta—do I see six wires? If so, this is not the easiest sort of stepper motor to drive. (Though if you have sufficient interest in driving stepper motors, you can certainly learn to make a six-wire stepper work.)

I’ve lately spent considerable time with stepper motors, and found valuable learning in the experience. Be aware that quality stepper motors of known provenance and published data sheets are inexpensive and easily purchased on eBay, Amazon, etc. To my mind, the easiest stepper motors to drive are four-wire, bipolar stepper motors. So far as I know, this type of stepper motor is also compatible with each of the common macro-stepping controllers (Cognisys StackShot, WeMacro, and MJKZZ).

As these motors are inexpensive and easily obtained, it might not be efficient cost/benefit to spend much time salvaging the existing motor—unless you have enough interest in stepper motors that the education from this exercise is worth your time.

On the other hand, in your images, there seems to be a set of cut wires leading to a black object that looks to be made of aluminum. What is this, I wonder? Unlike the black and silver assembly, the identity of this seems less clear. Is it a servo motor, piezo-motor, or something else? Perhaps worth investigating.

Cheers,

--Chris S.

[mawyatt]

Chris,

I can confirm that the Stackshot, Wemacro & MJKZZ 4 wire stepper motors all work and are interchangeable with the controllers for each as well. You just need the right custom made adapter cable, and take into account (or program) the stepper motor step size (200 or 400 steps per rotation) with the screw thread pitch to properly compute the step size at the focus rail stage.

This is very nice and convenient for us users, and hat's of the Paul, William and Peter for making this happen

I also wondered about the "Black Box", maybe an encoder

Best,

[ray_parkhurst]

This said—and having no argument with Lou that the motor might be a dual-shaft Vexta—do I see six wires? If so, this is not the easiest sort of stepper motor to drive. (Though if you have sufficient interest in driving stepper motors, you can certainly learn to make a six-wire stepper work.)

Don't be afraid to work with the 6-wire motors, which are generally unipolar types. They will usually have two black wires, which are the center tap points of the two coils. If you simply leave those wires "floating", and just use the other 4, the motor will operate in bipolar mode. Only caveat is if the windings were designed for high voltages, in which case putting two in series will increase the required operating voltages even higher, possibly making it impossible to work with the controllers that have been discussed. If the motor is rated for 6V or higher in unipolar mode, it's not going to work with the WeMacro or MJKZZ controllers with two windings in series. I don't know the limitations for the Stackshot.

[Scarodactyl]

Alrighty, some updates here.
I took the motor assembly off to look at more closely. The motor is branded by a company called Distributed, Inc., with a part number and a serial number as well as a phone number:

A quick googlin' didn't give me anything.
Another sticker says Oriental Motor Co Ltd, with Vexta peeking out from under. It does indeed have six wires.
I took the cover off the black box and got some pictures:



Beats me, but I don't know anything so that isn't surprising.

I didn't feel great about doing a quick bad test of the lens and then abandoning it, so I thought I should try something a bit better. I realized with the motor off I could almost fit the lens onto my Nikon smz-1b's base. All I had to do was take off the two bottom shiny metal things (still attached one bottom left):

It prevents the lens from, uh, doing what it's doing in the picture. I'm curious what that is about.

Speaking of things I'm curious about, I kind of wonder what the parfocal lock does.
Anyway, it fit close enough that the set screw mostly held it in place:

I took a few shots of an old dusty piece of RAM because I had it on hand and it gave me a sense of the depth of focus I guess. It was definitely different from handling a stereozoom scope, changing the distance to the RAM with the microscope focus mount and then change the focal length(?) with the gear control until it was in focus. Note there is probably plenty of vibration going on and the lighting is a fiber optic source held in my hands so this isn't the most scientific test, just in case you thought it was.



100% crop
Unfortunately, in spite of how much fun it was to cobble this together I think the results are pretty underwhelming. I imagine better performance could be coaxed out of it with less vibration and finer focus but probably nothing that great. But it is technically functional.

I also had a look at the oriel. It comes easily off the base and the filter holder comes off easy too.

But beyond that I have no idea how to use the thing. Just by looking through it with my eye it seems to magnify things a little bit, with a similar effect in either orientation. I can take pictures through it with my phone camera which come out OK. There are no threads so to hook it up to the camera I'd probably have to insert an appropriately-sized tube (43mm) into the metal lip above the lens which does have a pair of set screws (one sheared off). But just holding it against my lensless camera had about a foot-long focal length(working distance?), and images captured were very very soft.

I don't know if this means the lens needs to be a further from the camera? Or if it needs some more optics to function? Whatever it is, I know I'm not doing it right.
I am coming to the conclusion I need to learn a lot more about optics.

[mawyatt]

Vexta is the motor manufacture I believe.

The items in the black box apparently are as mentioned some sort of shaft encoder. The position of the shaft is sensed as the half disc rotates thru the 2 optical detectors (black plastic "U" shaped devices) and blocks the LED (one side) light to the photo detector (other side). The 3 wires going to the connectors to each detector are Ground, Signal and Power most likely. It appears as each detector has a single resistor which would be a current set for the LED. My guess is with the 2 detectors the Controller could sense when the shaft half disc is between the 2 detectors (one ON and one blocked OFF) and which way the shaft is rotating (timing between detector's ON and OFF).

Sorry, cant help with the optics, others can help here.

Best,

[Scarodactyl]

That makes sense! And now I know what was on my standalone Makrozoom setup--a shaft encoder sans motor.


OK, time for another wall of pictures with my further experimentation.

First up, a bit more on the big yellow lens.
So, I unscrewed the set screws and took off the yellow filters from either end...


except the 'filters' are colorless and everything else is so yellow.
OK, maybe the next layer is a filter. We've got those dual slot things to unscrew it, and once again I have a highly specialized at hand just for this job:


The black retaining ring unscrewed easily enough. But shaking the lens, etc didn't make them come out, so it was time for another highly specialized tool:

Yes that's off my GPS mount. It got a great grip, held on tight and the lens/filter didn't budge at all.
So I'll be honest I'm not sure what my next move is? I guess take some really yellow pictures?

And onwards to the last lens on this list, the Oriel lens. The results I got last time were really poor, but looking through it just with my eye yields such better results that I wanted to have another go at it.
So to start out, ehre's a quick shot of my carpet through the lens with my phone:

So, the first time around I just held it against the camera and took a few shots. They showed a lot of haloes and looked awful.
So, in my shotgun approach, I figured my first attempt should be direct projection with a longer tube length. The wrinkle: the side I wanted to put it on has a 43mm diameter ID which isn't very standard.

Fortunately I have pvc and duct tape. A bit of sandpaper on the other end of the pvc let me thread an m42 mount on it, not perfectly but close enough to hold it.

Summary: bad results again.

Obviously shiny white PVC isn't the best material but I don't think that's the problem there. I figured the shiny metal bit at the end, which has a flat glass plate in it, might be causing problems, so I removed it.Unfortunately my beautiful improvised mount attached to that metal bit, so I just taped it together.


I should have done this on the carpet again. It is a little better, but even lower light has a lot of that bad glow.
As a side-note, I also tried just holding the lens against the front of the camera again with no extension, and it now focuses...two rooms away??

I really need to learn more about optics. I guess it's just a lot closer to the sensor now?
In a last-ditch effort I figured, maybe...

This is one of the heads off my AO one ten. Why not try some infinity correction? It's not trinocular unfortunately so just shot through the eyepiece with my camera


Ugh. It's a bit better but still awful.
But if I just hold it over my phone, there's obviously a lot of vignetting (this is cropped a lot) but the image is a million times better.


So... I have no clue. I guess either a) I am going about this adaptation all wrong (quite likely) or b) you can't judge a lens by how well it works when held over your phone camera (also likely).

[Lou Jost]

I definitely admire your determination and tool creativity!

[genera]

That isn't a shaft encoder. It's two end of travel limit switches to keep whatever the motor was moving from driving into hard mechanical stops and possibly jamming. If you look closely you'll see that there are two independently adjustable half-discs. I suppose they could be used to determine direction but it seems like a very costly and overly complex way to determine something that the stepper controller should already know.

I've heard one explanation for cutting wires or inflicting some other damage that makes some sense to me. If an item that has been fully depreciated for tax purposes, still has value when it's disposed of, the company has to account for that residual value as profit. To avoid the paperwork that goes along with that they damage the item to render it inoperable and valueless. I've purchased a number of items over the years that have had similar treatment: power switches bashed in, fuse holders removed, or power cords or other cables cut.

A recent example, that I think falls into this category: I bought a Newport motion controller on eBay that was advertised as "not working". When I got around to looking at it I found that the power supply for the LCD backlight had been removed and taped to the inside of the top cover. The only repair required to make the controller fully functional was the re-installation of that little power supply. IMO someone took a more thoughtful approach to damaging the controller. You might consider that as soft damage, similar to cutting a cable to a length where it could be spliced, as opposed to hard damage (possibly inflicted by someone with no discretion in the matter) such as cutting a cable too short to splice or throwing a power supply away.