Etendue Mejiro lenses on eBay now

physicsmajor · Post by **physicsmajor** » Wed May 27, 2020 12:59 am

You can tell Raf they've got at least one more customer if they did go straight to SM2 from V38 (I'd buy 3 of those).

chris_ma · Post by **chris_ma** » Wed May 27, 2020 2:57 am

quick update:
Raf confirmed that he can make a V38 to SM2 (without flange, so that it can be fully inserted into the SM2 tubes), it will be around 30USD.

I ordered two and will report back about the fit on the Mejiro and SK lenses (can't imagine any problems since Robert mentions the other adapter fitting well).

RobertOToole · Post by **RobertOToole** » Fri May 29, 2020 11:42 pm

chris_ma wrote:I've sent a mail to Raf asking if it's possible to make an adapter V38 to SM2 since that would be more useful then to M42 for me - will report back when I hear back.
chris

Good idea, I'm sure he can do it, I would buy some at the same time if he does a run. I did not ask for this the first time since I was using both M42 and SM2 but since the early days in 2017, I now use the SM2 exclusively, so the M42 setup has been sitting on the shelf since then. V38 to SM2 would be better.

Also V38 to V38 would be a good one also, for lens stacking coupling.

Best,

Robert

dmillard · Post by **dmillard** » Mon Jun 01, 2020 8:22 am

The seller now has an additional group of these lenses for sale:

https://www.ebay.com/itm/283898700866?ul_noapp=true

physicsmajor · Post by **physicsmajor** » Thu Jun 11, 2020 12:48 pm

Raf just made available V38 to SM2 male adapters which should make using these (and other V38 mount lenses) as tube lenses a real pleasure with Thorlabs gear. My order is in.

Not sure if I can directly link to Raf's site, but it is called "38mm clamp to SM2".

The second batch of these lenses still has 4 available as of this writing.

chris_ma · Post by **chris_ma** » Thu Jun 11, 2020 12:52 pm

physicsmajor wrote:Raf just made available V38 to SM2 male adapters which should make using these (and other V38 mount lenses) as tube lenses a real pleasure with Thorlabs gear.

good to know, haven't heard back from Raf about the prototype, will check with him tomorrow.
chris

ps: hmm, the web page lists 8 in stock, maybe he has shipped mine already and forgot to tell me :)

JKT · Post by **JKT** » Thu Jun 11, 2020 2:45 pm

RobertOToole wrote:Also V38 to V38 would be a good one also, for lens stacking coupling.

For Makro Iris lenses 37mm to 37mm reversing ring should work as well and that is coming soon.

RobertOToole · Post by **RobertOToole** » Thu Jun 11, 2020 6:09 pm

JKT wrote:
RobertOToole wrote:Also V38 to V38 would be a good one also, for lens stacking coupling.
For Makro Iris lenses 37mm to 37mm reversing ring should work as well and that is coming soon.

The hood sets the element back a few mm on some lenses so really the best way would be V38 to V38 or even better mounting in the Sm2 tube at the rear so the lenses can touch or even mount one inside the shroud of another. Male to male thread mounting using two hoods adds a few mm on some lenses I think.

Lens combos need to be tested for sure, some like spacing, some have to almost be touching. Tube mounting helps.

Best,

Robert

RobertOToole · Post by **RobertOToole** » Thu Jun 11, 2020 6:12 pm

Also it might not be a bad idea for US guys to share express shipping costs to reduce the cost per adapter, normal mail from the RUS takes forever!

I will have some adapters coming soon express if anyone is interested.

Best,

Robert

JKT · Post by **JKT** » Fri Jun 12, 2020 12:16 am

I agree that the SM2 solution is very handy ... as long as both lenses fit inside the tube. For the Macro Irises that is likely the case. The adjustment and lens change is not as easy I would like, though.

The problem with the V38 to V38 adapter is that it is fixed length while the lenses are not. So it is better than 37mm to 37mm, but still not optimal. I'll have to see if I could design an adjustable and modular adapter for that. The modular part would mean I could change the V38 on one end to filter thread when necessary.

RobertOToole · Post by **RobertOToole** » Fri Jun 12, 2020 7:46 am

JKT wrote:I agree that the SM2 solution is very handy ... as long as both lenses fit inside the tube. For the Macro Irises that is likely the case. The adjustment and lens change is not as easy I would like, though.

Not true, both lenses do not have to fit inside of the lens tube. I've been using the same Thorlabs SM2 tube setup now for 4+ years and it turns out that the main strength of the setup is ability to reconfigure for a new lens, or stacked lens combinations in this case. You only need threads on one side of each lens to set it up, and the rear lens or both lenses can be a larger diameter than the SM2 tube. Simple. Easy.

Feel free to come up with a better solution, just don't forget to share the results here. I'm always looking forward to trying new ideas and giving them a test drive

Best,

Robert

JKT · Post by **JKT** » Sun Jun 14, 2020 1:11 pm

IF I think I have a solution, I'll post the sketches for comments. Way cheaper that way.