Thorlabs SM2 Parts Available From China

[RobertOToole]

After Lou posted a link just now for a Neewer Z-flex tilt head on Amazon it reminded me to search Alibaba for Chinese SM2 threaded parts. The reason is that I think I might have bought some Thorlabs knock-offs on eBay last week, maybe, maybe not, but I emailed Thorlabs and they weren't concerned at all and told me nothing to worry about. That made me think Thorlabs already knows about it.

So it turns out you can now source SM1, SM30, SM2 threaded parts from China now. They look interesting.They aren't knock offs I notice, the parts are different, not exactly the same dims and features as Thorlabs gear but still interesting. Some parts cost the same generally some are up to 40% cheaper. I might order something to try them out.

Thanks for the reminder to do the search Lou!

Best,

[Lou Jost]

Wow, thanks for sharing your discovery!

[Macro_Cosmos]

Yeah, OEAbt has been lifting .step files from Thorlabs' website and making identical parts. The quality is alright. I really, really dislike the labelling on the tubes.
Cannot really blame them, if you go to thorlabs.cn and check the prices, items are twice as expensive, likely due to the governments of both countries.

SMxx is not something owned by Thorlabs, it is a standard imperial specification for optics. Anyone can lift the files and get them made for cheaper prices, the issue would be the threading. There are various Chinese companies that sell SM-specification taps, the SM2 type is $100. For both internal and external threads, that would be a hefty $200.

[RobertOToole]

Yeah, OEAbt has been lifting .step files from Thorlabs' website and making identical parts. The quality is alright. I really, really dislike the labelling on the tubes.
Cannot really blame them, if you go to thorlabs.cn and check the prices, items are twice as expensive, likely due to the governments of both countries.

SMxx is not something owned by Thorlabs, it is a standard imperial specification for optics. Anyone can lift the files and get them made for cheaper prices, the issue would be the threading. There are various Chinese companies that sell SM-specification taps, the SM2 type is $100. For both internal and external threads, that would be a hefty $200.

Yes. Correct. SM2 is just easier to remember, rather than 2.035"-40.

Newport (someone bought the company now) makes a 2 inch lens tube system and they all work together with SM2 perfectly since they use the same threads. I used to buy more Newport since there was more available, they made more parts, now Thorlabs seems to be the biggest with lots of new stuff all the time.

Also RAF will make SM2 compatible parts and sell them as SM2 threaded but wont copy a part directly. Even RAF adapters are being copied now though it looks like.

Newport: https://www.newport.com/f/lens-tube-mul ... ns-holders

Best,

Robert

[rjlittlefield]

SM2 is just easier to remember, rather than 2.035"-40.

My curiosity is overwhelming.

Normally a thread diameter will be some nice round number, either in the units where it is specified or in some original units that have been converted. But I can't see where 2.035" fits that pattern.

So, how on earth did SM2 come to be specified as 2.035"-40?

--Rik

[blekenbleu]

My guess: threads formed by rolling on nominal 2-inch o.d. tubing

[RobertOToole]

SM2 is just easier to remember, rather than 2.035"-40.

My curiosity is overwhelming.

Normally a thread diameter will be some nice round number, either in the units where it is specified or in some original units that have been converted. But I can't see where 2.035" fits that pattern.

So, how on earth did SM2 come to be specified as 2.035"-40?

--Rik

Originally I was attracted to SM2 parts when I read somewhere that that SM2 and M52 are interchangeable/compatible. Not everything on the internet is true, big shock right, they are not, but they are close enough that standard M52 that Male SM2 will thread into Female M52 but not the other way around unfortunately. Could that be a factor maybe?

Best,

Robert

[Macro_Cosmos]

My guess: threads formed by rolling on nominal 2-inch o.d. tubing

The 2-inch is not o.d., it is i.d. and it is slightly more than 2 inches, 2.035 or something ridiculous.

[Bakwetu]

I really need to finally make my build with sm2 tubes, but I am having a hard time estimating what I need. The adapters I think I get but what SM2 tubes do I need? Anyone with experience that has some input?
I use a full format Canon eos 5dsr and have these tube lenses:
Scitex LFOV 108 mm/f5.6 - RAF has M45 to SM2
Mejiro etendue OTH075 90 mm/f5.6 & OTH050 90 mm/5.6 (attached to a Dalsa industrial camera now) - Raf has V38 to SM2
Schneider componon 150/f5.6, black with silver filter threads - Raf has M42 to SM2. This will not fit inside the SM2 tubes I guess.
Schneider macro symmar 120/5.6 with some v83 to M58 mm adapter attached now - V38 to SM2

main lenses to be reversed:
Schneider componon 35mm/2.8 newest model - V38 to SM2
Schneider componon 28mm/2.8 newest model - V38 to SM2
Schneider componon 35/4 modded with 80mm's aperture to open fully - m30.5 to m42X1 then the M42 to SM2?

I already have a mjkzz setup that I can use with the Raynox tube lenses and the Mitutoyo's I have.
On elongation I have Rayfact VL1.4X - If I interpret Robert's setup right, this needs a 6'' tube and a m55 f - m52 m stepdown or I could get a m55 to sm2 from Raf

So I need :
SM2 to Canon EOS EF adapter
2 v38 to SM2
1 or 2 M42x1 to SM2
M30.5 to M42x1
SM2 Variable extension tube
SM2 tube (size?) female to female
SM2 tubes female to male, I'm uncertain which ones I need?
arca swiss plate, clamps and sm2RC rings

[RobertOToole]

Hi Bakwetu,

There is lots of info all over my site, these two links have equipment lists, there are more:

SM2 parts list on my site: https://www.closeuphotography.com/52mm-setup

CPN2.8/28 setup: https://www.closeuphotography.com/schne ... ponon-lens

I really need to finally make my build with sm2 tubes, but I am having a hard time estimating what I need. The adapters I think I get but what SM2 tubes do I need? Anyone with experience that has some input?

There is a seller now on eBay here in the US with a nice selection of SM2 parts for 30-40% off Thorlabs direct selling prices.
Search 'Thorlabs SM2' on eBay. The seller is excellent with communication and after sales help.

I use a full format Canon eos 5dsr and have these tube lenses:
Scitex LFOV 108 mm/f5.6 - RAF has M45 to SM2
Mejiro etendue OTH075 90 mm/f5.6 & OTH050 90 mm/5.6 (attached to a Dalsa industrial camera now) - Raf has V38 to SM2
Schneider componon 150/f5.6, black with silver filter threads - Raf has M42 to SM2. This will not fit inside the SM2 tubes I guess.
Schneider macro symmar 120/5.6 with some v83 to M58 mm adapter attached now - V38 to SM2


main lenses to be reversed:
Schneider componon 35mm/2.8 newest model - V38 to SM2
Schneider componon 28mm/2.8 newest model - V38 to SM2
Schneider componon 35/4 modded with 80mm's aperture to open fully - m30.5 to m42X1 then the M42 to SM2?

For the f/2.8 lenses, the normal stackable SM2 tubes and the V38-SM2 adapters allow mounting inside the Sm2 tubes. For the 4/35 it depends on the model, I usually mount these from the front for reverse install in a stacked setup. You can use a step-up to M52 and use a thorlabs external only threaded tube to mount the 4/35 backwards on the TL tube.

I already have a mjkzz setup that I can use with the Raynox tube lenses and the Mitutoyo's I have.
On elongation I have Rayfact VL1.4X - If I interpret Robert's setup right, this needs a 6'' tube and a m55 f - m52 m stepdown or I could get a m55 to sm2 from Raf

So I need :
SM2 to Canon EOS EF adapter
2 v38 to SM2

The V38>SM2 are the main adapters I use now.

1 or 2 M42x1 to SM2
M30.5 to M42x1
SM2 Variable extension tube
SM2 tube (size?) female to female
SM2 tubes female to male, I'm uncertain which ones I need?

if you have the budget its best to buy both stackable, these have male and female threads, and external only threaded tubes and internal only threaded tubes. This way you can adapt almost any kind of setup.

arca swiss plate, clamps and sm2RC rings

See this link for SM2 studio setup with a typical parts list: https://www.closeuphotography.com/52mm-setup

I do plan to post more examples and more parts lists for typical setups on my site, but other more important issues have taken up and will be taking up more of my time. I thought things were supposed to get better after the peak of the pandemic? At this rate I wont have time to update the SM2 pages on my site until sometime in 2023!


Feel free to message or email me with specific recommendations and I promise to answer when I get some free time.


Best,

Robert

[RobertOToole]

Quick addition to the thread that hopefully will help people visualize using tube lenses and reversed lenses in a stacked setup with Thorlabs SM2 parts.

I actually found the page using google search! The information below is from my Scitex S3 110mm test, this lens one of the best tube lenses I l've ever tested FYI.

For more info and a larger version of the illustration above:

https://www.closeuphotography.com/scitex-s3-110mm-lens

PARTS LIST AND LINKS
Tube lens: Rodenstock Scitex S-3 5.0/110 lens
Front lens: Schneider Componon 2.8/35 lens
-Thorlabs Stackable SM2 lens tube, SML03 to SM2L30: https://www.thorlabs.com/newgrouppage9. ... up_id=3383
(note that a pair of SM2 retainer rings are included with an SM2 tube)
-Thorlabs SM2A29 - Adapter with External SM2 Threads and Internal M39 x 1.0 Threads: https://www.thorlabs.com/thorproduct.cf ... ber=SM2A29
-RafCamera 38mm clamp to SM2 male thread adapter: https://rafcamera.com/

Hope this helps.

Robert

[Bakwetu]

Thanks, I've looked through your site of course, but I think it is not until you actually used the setups that you find out what you need. The sm2 is system is a bit expensive so I thought I'd ask people with experience what you really need. Like which and how many tubes are needed for a setup?

Just thinking about the tube lenses I have now (SK makro-symmar 120, Mejiro 90, LFOV 108 & maybe SK 150mm) what is needed for going to infinity? Any extra lock rings needed?
In your example above with makro-symmar 120+SK 28 it looks like you have one 3'', one 1.5'' and one 1'' tube. All stackable fem-male ones.
I am guessing the fem-fem tubes are mainly to connect the variable tube with external threading?

[RobertOToole]

Hi Bakwetu

Thanks, I've looked through your site of course, but I think it is not until you actually used the setups that you find out what you need. The sm2 is system is a bit expensive so I thought I'd ask people with experience what you really need. Like which and how many tubes are needed for a setup?

Wish my site was more helpful in regards to detailed featured setups, in all seriousness I planned to get a lot more updates in regards to SM2 part setup but I have problems finding enough time, maybe this summer hopefully?

Look at: https://www.ebay.com/usr/onroutetwo?
I've bought from the guy before. Very helpful. He has 3 inch SM2 SM2L30 for $26 and 2 in SM2 SM2L20 for $23. Even the SM2V10 adjustable for $34.

Just thinking about the tube lenses I have now (SK makro-symmar 120, Mejiro 90, LFOV 108 & maybe SK 150mm) what is needed for going to infinity?

And I just had a Makro-Symmar 120 set up two days ago. I should have thought of taking some pictures of the setup! Also the SK 150!

If I have time I can help this weekend maybe I can help with setup and add the details to my site and post them here.

Any extra lock rings needed?

A pair of rings usually comes with each tube from Thorlabs. You don't have to use them, I just like keeping things tight rattle free.

In your example above with makro-symmar 120+SK 28 it looks like you have one 3'', one 1.5'' and one 1'' tube. All stackable fem-male ones.
I am guessing the fem-fem tubes are mainly to connect the variable tube with external threading?

Yes, instead of using one, I use multiple shorter tubes so changing lenses is quicker, like going from 2.8/35 to 2.8/28.

I'll see if I can help this weekend.

Best,

Robert

[Bakwetu]

Don't worry, your site IS very helpful and you do have photos with setups to explain how things work. But photos of more setups is always welcomed and especially which sm2 tubes are needed.

I have looked at US ebay listings, but since I'm in EU the total price will be worse. Apart from shipping we also pay 25% VAT on the total price, including the shipping cost and we also pay an extra fee for each shipment for the customs to make the paperwork. As an example, there is a listing for a 3'' sm2m30 now at $32+$16.65 shipping. With tax and customs fee it will end up $70 which is higher than from Thorlabs themselves. With prices like that I have to take some care with what I buy. Oneroutetwo does not ship to the EU unfortunately. There is someone in Ireland that sells the adjustable tube sm2v10 at a good price, but he doesn't sell to private buyers in the EU.

I have searched now and then for sm2 parts on ebay but it is rare that they will come up at prices that make sense, so I think I'll have to buy from Thorlabs directly since they ship from inside EU and I can get more tubes in one shipment without the hassle of ebay.

[RobertOToole]

Bakwetu,

Don't worry, your site IS very helpful and you do have photos with setups to explain how things work. But photos of more setups is always welcomed and especially which sm2 tubes are needed.

Thanks. I'll work on that.

The whole point of my site is to help people, I make no money from it, so I'm always interested in improving the content. Other sites, almost all camera and lens sites, push products with lists of links to make a sales commission, every "rumor" site is setup this way.
I don't push anything on buyers but then I don't have complete lists of products to buy either.

.....I have looked at US ebay listings, but since I'm in EU the total price will be worse. ......

I didn't take duty into consideration!

We are spoiled in the US. In my entire life, I'm 52, I've only been charged duty once, on a Qioptiq Linos inspec.x lens, they charged me $26 and I was complaining but it was the first time I had to pay duty. The only reason is was $26 is because the shipper in Korean helped me out with the cost declaration, if you know what I mean, without me even asking for help. Korean sellers are world-class!

Once I was told by the owner of a big US company that instead of saving money on shipping imported products into the US in bulk, they break shipments up into 10 shipments to avoid duty. They ship them USPS and only one out of 10 or 20 actually gets inspected and the duty is much less since its a 1/10th of the quantity! Avoiding taxes and duties is the very core of the way-of-life for business here in American. All our largest US companies, aren't American at all, they are based in Ireland or the Seychelles to avoid tax and it's accepted and even revered.

Best,

Robert