$15 Rodenstock 240mm Ysaron vs Raynox vs ITL200 TL Test

[RobertOToole]

Thanks Robert. That is so elegant.

BR

John

Thanks.

Just made this to help, it's a little crude

Is this better?

[dolmadis]

Very interesting. Thank you for the diagram.

I think that I need to purchase some of the parts and play with them to get a real appreciation of the mounting innovation.

To make things more certain for ordering could you tell me what the parts are called (part numbers would be ideal) and how many of each I would need to create a trial set up.

Thanks Robert,

BR


John

[RobertOToole]

Very interesting. Thank you for the diagram.

I think that I need to purchase some of the parts and play with them to get a real appreciation of the mounting innovation.

To make things more certain for ordering could you tell me what the parts are called (part numbers would be ideal) and how many of each I would need to create a trial set up.

Thanks Robert,

BR


John

Yes, of course.

Basic set-up; Tubes, and M42 to SM2 adapter.


Thorlabs SM2 Stackable Extension Tubes
Official name: Ø2" Stackable Lens Tubes
Retail price: $23-36 ea.
Link to Thorlabs site:https://www.thorlabs.com/newgrouppage9. ... up_id=3383
Note: 3 or 4 pcs in different lengths are recommended

Thorlabs SM2 Adapter
Official name: SM2A24
Specs: Adapter with External SM2 Threads and Internal M42 x 1.0 Threads
Retail Price: $23.64 each
Link to Thorlabs site: https://www.thorlabs.com/thorproduct.cf ... ber=SM2A24
Note: 2 pcs are recommended

You would also need a SM2 to camera mount adapter. Raf has SM2 to Sony E or Nikon or can make anything you need. You can also use M52 Female to camera mount adapters.

Note: SM2 male will not thread into M52 female, but M52 male will thread into SM2 Female.

Recommended but not necessary:

Thorlabs Variable Extension Tube
Specs: SM2V15: 1.31" (33.3 mm) Ø2" Lens Tubes with Rotating Optic Adjustment)
Retail Price: $53 each
Link: https://www.thorlabs.us/thorproduct.cfm ... ber=SM2V15


This is for the basic setup but not the mounting gear, I can send that list separately.

Best,

Robert

[dolmadis]

Thanks Robert.

Yes, I would like the mounting gear list when you have a mo.

I had not appreciated SM2.

BR

John

[RobertOToole]

Thanks Robert.

Yes, I would like the mounting gear list when you have a mo.

I had not appreciated SM2.

BR

John

The Thorlabs parts are not too expensive direct but if you are patient SM2 parts do turn up on eBay from time to time. I have picked up SM1 and SM2 iris assy. this way.

Also the SM2 uses the 2 inch industry standard thread size that is shared with Newport 2 inch tube systems:

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

I can confirm that the threaded parts are interchangeable, some of the hardware like clamps might not be, but its nice to be able to use tubes, etc, interchangeably.

The proper thing to do would be for me to post the hardware list in a new thread so it will be easier to find in the future. I'll do that later when I get some free time and post the link here.

Best,

Robert

[dolmadis]

Great idea for a new thread..........may be a FAQ?

BR

John

[Saul]

If somebody is interested:

Ysaron 240mm tube lens M42 adapter
http://www.photomacrography.net/forum/v ... 733#250733

[dolmadis]

yes, thanks, Saul

[Macro_Cosmos]

I'm going to suggest against mixing the thorlabs m52/SM2 with ordinary m52x0.75 accessories without a proper adapter. Sure it's possible to fit them in with brute force, I used to do that. The optical axis throw off is enough to be visible. I wrote about it in my capstone thesis project, which I might release to the public soon. It has something to do with focus stacking, microscopy, and building a setup.


(Oh no, it's simple not simply... oh well, too late.)

Thorlabs offer these:
https://www.thorlabs.com/thorproduct.cf ... ber=SM2A52 extSM2 int m52x.75

https://www.thorlabs.com/thorproduct.cf ... ber=SM2A53 extM52x.75 int SM2

They are even cheaper than the Raf part. The Raf ones are $25 or $29, these are $20.


For the F-mount, buy this:
https://www.thorlabs.com/thorproduct.cf ... er=SM2NFM2
Yeah, $117.67 is a lot, but you won't regret it. It does not wobble at all, even less than mid-tier Nikon lenses. Very precise and tight fit. I have simply not used a camera adapter that is more precise than this one. I've tossed out all my cheap adapters and now exclusively use this one. You will need to salvage a screw to enable the lock stop mechanism, luckily Thorlabs have left grooves for the screw to fit. The screw can be found on cheapo adapters, take one off and throw the adapter away.

To save some bucks, one can get the Nikon BR2/BR2a and combine it with an M52x.75int>SM2
The BR2 is really tight as well. I used to think that $118 premium adapter is a waste of money, since it doesn't even provide the stopping screw or anti-reflectance internal coatings; but I've grown to appreciate it. It never failed me.

Thorlabs' SM2 tubes do not have any internal anti-reflectance coatings, pretty unacceptable for that high pricetag. I just roll flocking adhesives and insert them into the tubes.

[Lou Jost]

Macro-Cosmos, is this really important when stacking? The blurry corner in one frame will be sharp in another.

[Macro_Cosmos]

Macro-Cosmos, is this really important when stacking? The blurry corner in one frame will be sharp in another.

Optical axis misalignment? Yeah it will have an effect, whether detrimental or not would depend on the mag. I assume you mean focus stacking not stacking lenses? Yes the effect is visible and bad. I have many sample images to illustrate the issue. Will write up a post after the annoying exams today.

In short, weird complications arise when there's a misalignment, especially with my setup where the itl200 isn't focused to infinity. It causes fine details to duplicate themselves, producing overall soft images. CA may also be exacerbated, and the usually negligible highlight haloeing on some specimens such as blue and green papilio butterflies will become smears in the stack. At 10x, I can't see the issues, but 20x it's pretty horrible. My 20x is also slightly decentered.

The 2x I illustrated above was bad enough to be visible on a 1080p monitor without zooming in. I used m52x.75 ring forced into SM2, and also a focusing helicoid which wasn't cheap. The manufacture was honest enough to tell me that optical axis was never a concern as close to all his customers use the helicoid for non-macro means.

When the misalignment is severe, one would discover that no matter how the lens is focused, it always seems to be not in focus. Being in the corner just makes this worse.

I have also found out it's important to use retaining rings which I'm sure Rob is well accustomed to, the thorlabs tubes all come with retaining rings to fix the optic in place so it doesn't wobble. My very first itl200 setup was bad because of that.

Hope my ramblings make some sense.

[Macro_Cosmos]

In addition to above, my findings might be somewhat anecdotal. When a tube lens isn't focused to infinity, optical axis misalignment really matters. Slight alignment shouldn't theoretically matter with an infinity setup, if my understandings are right. So what's illustrated above might be almost entirely due to my qwerky itl200 setup.