Stacked Lens vs APO objectives at 4x with Surprising Results

Have questions about the equipment used for macro- or micro- photography? Post those questions in this forum.

Moderators: Pau, rjlittlefield, ChrisR, Chris S.

ray_parkhurst
Posts: 2756
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Post by ray_parkhurst »

dolmadis wrote:Robert

Yes, I can see how that suggestion arose now.

I mentioned the 23mm lens because I have seen some guys in Poland on the Facebook Groups using this Reversed stacked on a Takumar 200mm f/4.

BR

John


Edit to add "Reversed"
Wow, that's 8.7:1. Would be good to see what they are getting.

ray_parkhurst
Posts: 2756
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Post by ray_parkhurst »

ChrisR wrote:
What will be the WD for these C-mount lenses?
17.526mm apparently:


http://www.ikegami.com/cb/products/pdf/ ... smount.pdf
Thanks for that. I was wondering what the difference between C and CS was.

So if the front 12mm threaded portion is removed, these lenses would have ~29mm WD. That's not too bad at all.

Edited to add: I'm referring to the 35/1.8 APO

dolmadis
Posts: 737
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Post by dolmadis »

ray_parkhurst wrote: Wow, that's 8.7:1. Would be good to see what they are getting.
From my notes..............

Actually one reported he used it at 3x to 8x varied by tube length without further details (I tried).

Field of view 5mm?

One had the lens mounted reverse on an RMS turret with the SMC Super Takumar 200mm f/4 mounted on to the trino.

The other custom reverse mounted the lens to a microscope tube in place of the turret where I assume that that this was an infinite microscope. His images were reported at 9x. Looked good but they were on FB format.

HTH


John

dolmadis
Posts: 737
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Post by dolmadis »

Addendum

There are two main versions of the 23mm.

One with an 09xx suffix on 5mp. Could be Apo.

The other (earlier) with 05xx. 3mp? Likely non Apo.

BR

John

dickb
Posts: 261
Joined: Mon Jul 05, 2010 1:54 am

Post by dickb »

ray_parkhurst wrote:So if the front 12mm threaded portion is removed, these lenses would have ~29mm WD. That's not too bad at all.

Edited to add: I'm referring to the 35/1.8 APO

Just to make sure everyone understands "removing the threaded portion" means cutting it off, not just removing the focussing adapter.

The rear lens of the 35/2.0 APO is much closer to the rear of the lens barrel, nowhere near as much WD can be gained by hacksawing that one.

dickb
Posts: 261
Joined: Mon Jul 05, 2010 1:54 am

Post by dickb »

dolmadis wrote:Addendum

There are two main versions of the 23mm.

One with an 09xx suffix on 5mp. Could be Apo.

The other (earlier) with 05xx. 3mp? Likely non Apo.

BR

John
No, both are the same non apo lens in slightly differing barrels. The 09xx has a 30.5mm filter thread, the 05xx doesn't, it is designed for clamp on filters. Same for the 28/2.0, 35/1.9 and others.

The apo 23/1.4 is clearly larger.

People looking for 23/1.4 Xenoplans should be wary of the 23/1.4 (4.0) variant - it is the same lens but has a fixed circular 4.0 waterhouse type stop instead of a variable aperture.

elimoss
Posts: 41
Joined: Wed Sep 12, 2018 11:31 am

Post by elimoss »

Robert, how do you align the wafer to the sensor plane for the test. Do you use some sort of shim tape or do you need something more precise?

RobertOToole
Posts: 1618
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

elimoss wrote:Robert, how do you align the wafer to the sensor plane for the test. Do you use some sort of shim tape or do you need something more precise?
:shock:

You are the very first person to ever ask me that!

I use Children's clay that I buy bulk on Amazon. I make 5 cone shapes to hold up a aluminum plate with the subject. Then I lower the camera rig, usually without the objective, on to the subject plate to deform the clay cones and align the plate.

Works perfectly to align the sensor and subject to about 20x or so in my experience.

Gionometers and shims also work but I found they can take 10X the effort and time for the same results.

Sometimes stupid simple is the best way :D

Best,

Robert

elimoss
Posts: 41
Joined: Wed Sep 12, 2018 11:31 am

Post by elimoss »

RobertOToole wrote:
elimoss wrote:Robert, how do you align the wafer to the sensor plane for the test. Do you use some sort of shim tape or do you need something more precise?
:shock:


I use Children's clay that I buy bulk on Amazon. I make 5 cone shapes to hold up a aluminum plate with the subject. Then I lower the camera rig, usually without the objective, on to the subject plate to deform the clay cones and align the plate.
That's pretty clever!! Thanks, Robert -- I'm going to have to try something like this with flat subjects.

Lou Jost
Posts: 4593
Joined: Fri Sep 04, 2015 7:03 am
Location: Ecuador
Contact:

Post by Lou Jost »

Yes, very clever!

dmillard
Posts: 595
Joined: Tue Oct 24, 2006 7:37 pm
Location: Austin, Texas

Post by dmillard »

RobertOToole wrote:Then I lower the camera rig, usually without the objective
:wink:

RobertOToole
Posts: 1618
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

dmillard wrote:
RobertOToole wrote:Then I lower the camera rig, usually without the objective
:wink:
Usually the crunching sound gives it away when I forget to remove the lens :shock:

RobertOToole
Posts: 1618
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

elimoss wrote:
RobertOToole wrote:
elimoss wrote:Robert, how do you align the wafer to the sensor plane for the test. Do you use some sort of shim tape or do you need something more precise?
:shock:


I use Children's clay that I buy bulk on Amazon. I make 5 cone shapes to hold up a aluminum plate with the subject. Then I lower the camera rig, usually without the objective, on to the subject plate to deform the clay cones and align the plate.
That's pretty clever!! Thanks, Robert -- I'm going to have to try something like this with flat subjects.
I didn't invent that technique, I need to give credit to Chris R.

mjkzz
Posts: 1237
Joined: Wed Jul 01, 2015 3:38 pm
Location: California/Shenzhen
Contact:

Post by mjkzz »

RobertOToole wrote:
elimoss wrote:Robert, how do you align the wafer to the sensor plane for the test. Do you use some sort of shim tape or do you need something more precise?
:shock:

You are the very first person to ever ask me that!

I use Children's clay that I buy bulk on Amazon. I make 5 cone shapes to hold up a aluminum plate with the subject. Then I lower the camera rig, usually without the objective, on to the subject plate to deform the clay cones and align the plate.

Works perfectly to align the sensor and subject to about 20x or so in my experience.

Gionometers and shims also work but I found they can take 10X the effort and time for the same results.

Sometimes stupid simple is the best way :D

Best,

Robert
Wow! I gotta try that sometimes, thanks Robert.

Post Reply Previous topicNext topic