Thorlabs SM2 Tube System Project

[RobertOToole]

Finally, after what seems like a couple of years, I finally picked up some SM2 parts from Thorlabs.

The fit and finish of the SM2 gear, at least so far, is great. Its good to see that the tubes fit very tightly with zero play or flex. The Thorlabs F-mount adapter seems to fit well also.



The SM2 setup should be more rigid, more flex free and easier to set up than my 52mm or 42mm set-up that I am using now.

BTW Thorlabs makes a nice externally threaded SM2 collar that slides over the Scanner Nikkor and makes a super convenient way to mount the lens.



A 1 inch front SM2 sleeve on the front of the lens can be used to mount a hood and for reverse mounting the lens.



These are some of the parts threaded together with the Scanner Nikkor installed (with lock ring) just to check the fit. I still have to mount the tube clamps to the quick release plate. I might also add a spacer between the clamps and the plate for more clearance.

FYI the SM2 Ø2" lens tube parts are compatible with female 52mm x 0.75 threads.Thorlabs (and Newport) use 2.035-40 threads that work perfectly with female 52mm x 0.75 threads but the female 2.035-40 threads will not accept the 52mm male threads more than a few turns.

PNs for the parts mentioned above.

SM2L15 Stackable Lens Tube 2" x1.5"
SM2RC SM2 Series Slim Slip Ring
SM2NFM2 Nikon Male F-Mount with SM2 ExternalThread
SM2T10 SM2 Lens Tube Coupler,1.0" Long
SM2T20 SM2 Lens Tube Coupler, 2.0" Long

More SM2 info on the Thorlabs site:
https://www.thorlabs.com/navigation.cfm?guide_id=2070


Robert

https://www.closeuphotography.com/[b][/b]

[typestar]

...These are some of the parts threaded together with the Scanner Nikkor installed (with lock ring) just to check the fit. ...

PNs for the parts mentioned above.
SM2L15 Stackable Lens Tube 2" x1.5"
SM2RC SM2 Series Slim Slip Ring
SM2NFM2 Nikon Male F-Mount with SM2 ExternalThread
SM2T10 SM2 Lens Tube Coupler,1.0" Long
SM2T20 SM2 Lens Tube Coupler, 2.0" Long...

Very nice setup, Robert!
As to be sure about the correct order, can you - please "put in order"
all shown/uses used parts - from rear to front?

.FYI the SM2 Ø2" lens tube parts are compatible with female 52mm x 0.75 threads.
Thorlabs (and Newport) use 2.035-40 threads that work perfectly with female 52mm x 0.75 threads but the female 2.035-40 threads will not accept the 52mm male threads more than a few turns.

So, in order to use an original NIKON BR2-A mount-adapter (which is less expensive compared to the Thorlabs SM2NFM2) --
will there fit a M52 x0,75 female to female M52 x0,75 adapter, mounted on the last tube used -- so inside this the Nikon BR2-A could be screwed in, then...?

Thankyou for your guidance !

christian

[mawyatt]

Hi Robert,

This looks great.

The Thor stuff is top notch...and expensive I know, I have bench, rail and a couple sliding clamps.

Are you mounting the clamps to the ARCA plate, then the plate to an ARCA clamp on the focus rail?

Best,

Mike

[RobertOToole]

These are some of the parts threaded together with the Scanner Nikkor installed (with lock ring) just to check the fit. ...

Very nice setup, Robert!
As to be sure about the correct order, can you - please "put in order"
all shown/uses used parts - from rear to front?

Hi Christian,

On a short 2 day holiday get-a-way with my wife so I have to be quick.

Here you are, order back to front.

SM2NFM2 Nikon Male F-Mount with SM2 ExternalThread
This part has male 2.035-40/ M52 threads.
SM2M30 SM2 Lens Tube 3" Long Extension
Female to female tube
SM2L15 Stackable Lens Tube 2" x 1.5"
Normal extension tube
SM2T20 SM2 Lens Tube Coupler, 2.0" Long
Rear sleeve for SN lens
SM2T10 SM2 Lens Tube Coupler,1.0" Long
Front sleeve for SN lens
SM2L15 Stackable Lens Tube 2" x1.5"
Normal tube used here as a lens hood

SM2RC SM2 Series Slim Slip Ring
These are used as tube clamps and will mount to the QR plate

So, in order to use an original NIKON BR2-A mount-adapter (which is less expensive compared to the Thorlabs SM2NFM2) --
will there fit a M52 x0,75 female to female M52 x0,75 adapter, mounted on the last tube used -- so inside this the Nikon BR2-A could be screwed in, then...?

Thankyou for your guidance !

Yes, a M52 x0,75 female to female M52 x0,75 adapter should thread into the BR-2A and the Thorlabs 2.035-40 normal tube (with male rear threads) or another brand 52mm tube without a problem. I tried a few.

The BR-2A was my original choice BTW. I decided to spend the extra money on the Thorlabs adapter to eliminate the extra female to female 52mm tube.

All the best,

Robert

[RobertOToole]

Hi Robert,

This looks great.

The Thor stuff is top notch...and expensive I know, I have bench, rail and a couple sliding clamps.

Are you mounting the clamps to the ARCA plate, then the plate to an ARCA clamp on the focus rail?

Best,

Mike

Yes thats the idea exactly.

My friend that's a machine shop guy, he usually helps me finish the projects before I mess things up too much at his shop, recommends that we open the 8-32 mounting hole and make it a 1/4-20. Then we (we means he) should mill a groove to seat the clamp slightly into the plate to take the stress off the 1-4-20 threads and fastener.

I am worried that there might not be a little bit of a clearance issue with the bottom of the camera body and the rail or column, since the slip ring mount height is so short.

I was thinking it might be best to add some kind of spacer between the slip ring clamps and the QR plate to give me more clearance for the camera body.

What do you think?

Robert

[mawyatt]

Hi Robert,

This looks great.

The Thor stuff is top notch...and expensive I know, I have bench, rail and a couple sliding clamps.

Are you mounting the clamps to the ARCA plate, then the plate to an ARCA clamp on the focus rail?

Best,

Mike

Yes thats the idea exactly.

My friend that's a machine shop guy, he usually helps me finish the projects before I mess things up too much at his shop, recommends that we open the 8-32 mounting hole and make it a 1/4-20. Then we (we means he) should mill a groove to seat the clamp slightly into the plate to take the stress off the 1-4-20 threads and fastener.

I am worried that there might not be a little bit of a clearance issue with the bottom of the camera body and the rail or column, since the slip ring mount height is so short.

I was thinking it might be best to add some kind of spacer between the slip ring clamps and the QR plate to give me more clearance for the camera body.

What do you think?

Robert

If the ARCA clamp is attached to the focus rail you may end up with enough clearance since the clamp sits above the focus rail stage. If you position the clamp towards the end of the stage if you can, this just might work. Sliding the lens down toward the end of the tube clamps will give additional clearance for the front.

Think you will end up with a slightly stiffer system by pushing the lens forward and have the ARCA clamp sitting forward on the focus rail stage rather then extending the tube clamps above the ARCA plate. Also the tube clamps don't have much surface interface area, where they attach to ARCA plate.

Anyway, just my thoughts.

Best,

Mike

[mawyatt]

Another thought looking at your image is to use a shorter ARCA plate, this will free up lens front.

If your thinking of a somewhat permanent lens mounting system for the SN, you could get the lens precisely aligned to the ARCA plate, then have your friend spot weld the tube clamps to the ARCA plate. Another option would be to use some strong long setting epoxy (not the 5 minute type, more like 2~4 hours setting time) between the tube clamp and ARCA plate, which would allow you to precisely align the lens before the epoxy sets.

Either way you would have a pretty stiff mounting clamp system for your SN lens.

Best,

Mike