DIC Question

Here you can discuss different microscopic techniques and illumination methods, such as Brightfield, Darkfield, Phase Contrast, DIC, Oblique illumination, etc.
Message
Author
microb
Posts: 729
Joined: Wed Mar 27, 2019 6:39 am

Re: DIC Question

#181 Post by microb » Tue Jul 20, 2021 7:42 pm

Breaking Taps had a video showing the fringing on a molded acrylic lens, which I think was actually polypropylene:

https://youtu.be/JNXgHbBIRYQ?t=1016

[I know I had added the link, but it disappeared. So added it.]
Last edited by microb on Wed Jul 21, 2021 5:53 am, edited 1 time in total.

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#182 Post by hans » Wed Jul 21, 2021 3:40 am

Got 3/32 bar from McMaster per Rathi, unsurprisingly shows similar strong inherent birefringence as the 1/16 and 1/8 I already had, didn't bother taking a photo. So why does Rathi fig. 3(b) shows so little shift of the fringe pattern? McMaster changed suppliers, or supplier changed manufacturing method? One confusing thing about fig. 3(b) is that going by the 10 mm scale bar the diameter of the circular stop is slightly more than 20 mm, but the widest bar shown in fig. 2 is 20 mm? Is your interpretation of 3(b) that it is showing close to the full width of the bar? McMaster currently does not sell bars narrower than 1" so maybe the bar in 3(b) is actually 1" and the 20 mm in 2(a) was just some preliminary sketch they didn't actually follow? (Seems like a lot of trouble for no obvious benefit to buy 1" bars and cut them down to 20 mm...)
microb wrote:
Tue Jul 20, 2021 7:42 pm
Breaking Taps had a video showing the fringing on a molded acrylic lens, which I think was actually polypropylene:
Link is missing...

microb
Posts: 729
Joined: Wed Mar 27, 2019 6:39 am

Re: DIC Question

#183 Post by microb » Wed Jul 21, 2021 5:56 am

hans wrote:
Wed Jul 21, 2021 3:40 am
Link is missing...
I know I had it there, so I edited it above. What I thought was interesting is that he molded the lens and where the plastic was pushed in there was more stress. So he built into the plastic a level of stress. I wonder if that could be done but I guess the rig with the screws is adjustable and the manufacture with a mold would probably be less predictable.

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#184 Post by LouiseScot » Wed Jul 21, 2021 10:11 am

hans wrote:
Wed Jul 21, 2021 3:40 am
Got 3/32 bar from McMaster per Rathi, unsurprisingly shows similar strong inherent birefringence as the 1/16 and 1/8 I already had, didn't bother taking a photo. So why does Rathi fig. 3(b) shows so little shift of the fringe pattern? McMaster changed suppliers, or supplier changed manufacturing method? One confusing thing about fig. 3(b) is that going by the 10 mm scale bar the diameter of the circular stop is slightly more than 20 mm, but the widest bar shown in fig. 2 is 20 mm? Is your interpretation of 3(b) that it is showing close to the full width of the bar? McMaster currently does not sell bars narrower than 1" so maybe the bar in 3(b) is actually 1" and the 20 mm in 2(a) was just some preliminary sketch they didn't actually follow? (Seems like a lot of trouble for no obvious benefit to buy 1" bars and cut them down to 20 mm...)
microb wrote:
Tue Jul 20, 2021 7:42 pm
Breaking Taps had a video showing the fringing on a molded acrylic lens, which I think was actually polypropylene:
Link is missing...
The Rathi paper isn't great for an apparently peer-reviewed publication. It would appear she was just an undergraduate student at the time - https://you.stonybrook.edu/sonikarathi/ ... nd-grants/
I suspect things in the paper have been somewhat idealised (as students often do... ) The paper has never been cited by anyone else. I'll still have a go at getting it working next month. If I don't get anywhere by the end of August then I'll abandon it.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Hobbyst46
Posts: 4277
Joined: Mon Aug 21, 2017 9:02 pm

Re: DIC Question

#185 Post by Hobbyst46 » Wed Jul 21, 2021 4:43 pm

LouiseScot wrote:
Wed Jul 21, 2021 10:11 am
The paper has never been cited by anyone else.
Agreed.
However, the likely audience of her paper is hobby microscopists rather than researchers, and hobby microscopists apparently rarely publish papers... Her supervisor and/or corresponding author would know more about it.
I am still crossing fingers to see a true DIY-DIC come to life !

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#186 Post by LouiseScot » Wed Jul 21, 2021 5:00 pm

Hobbyst46 wrote:
Wed Jul 21, 2021 4:43 pm
LouiseScot wrote:
Wed Jul 21, 2021 10:11 am
The paper has never been cited by anyone else.
Agreed.
However, the likely audience of her paper is hobby microscopists rather than researchers, and hobby microscopists apparently rarely publish papers... Her supervisor and/or corresponding author would know more about it.
I am still crossing fingers to see a true DIY-DIC come to life !
Yeah, but as you see from the above link she did it as a freshman undergraduate summer project, not even a final year honours-type project. It won't have been done especially for amateurs as the Applied Optics journal isn't easy to access. I can get to it via my Uni (I'm a registered student). Her undergrad supervisor probably didn't pay much attention to it... She's now a 'biomedical engineer' rather than any kind of microscopist.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Scarodactyl
Posts: 2775
Joined: Sat Mar 03, 2018 9:09 pm

Re: DIC Question

#187 Post by Scarodactyl » Wed Jul 21, 2021 6:22 pm

Saul seems to have gotten it working, though he only posted the two pictures.

BramHuntingNematodes
Posts: 1538
Joined: Tue Jan 21, 2020 1:29 am
Location: Georgia, USA

Re: DIC Question

#188 Post by BramHuntingNematodes » Wed Jul 21, 2021 6:28 pm

I guess now saul is too busy looking at everything in halo-free high contrast
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

User avatar
Dmi3n
Posts: 121
Joined: Thu Feb 06, 2020 4:14 pm
Location: Russia, Kaliningrad

Re: DIC Question

#189 Post by Dmi3n » Wed Jul 21, 2021 8:09 pm

Very interesting subject, will definetely give it a try. I have some experience with metalworking, although at the monent I don't have access to milling machines and lathes. Also I know some people who make scale models of buildings and they must have lots if different polycarbonate sheets. I've read the paper and one thing really bothers me - the relay lens to move back focal plane away from the objective. I think that it is better to find some objective with lower magnification with back focal plane far enough to place the prism and polish the technique with it, and then move to all those fancy lens.
I have only one question, how to find the back focal plane? I have two sets of identical Carl Zeiss Jena Planachromat objectives, RMS/160, one set is for phase contrast and one for polarisation (strain-less glass). Also I have set of infininty-corrected planachromats and one planapochromat, for use with reflected light illuminator (Auflichtkondensor). And a phase telescope (aka centering microscope), if it will help.
Does the back focal plane of infinity-corrected objective lie before or after tube lens?
I have no idea about some optics stuff, I am closer to mechanics as I've studied jewelry and machining in college.
Gear list:
CZJ NfPk and Polmi A w/ 45mm apo objectives, Phv, Epi Pol, trinocular
Gamma Hungary 3D-condenser
LOMO ОИ-28 Fluorescence Attachment
Set of Leitz Photar macro lens
Nikon D500 DSLR
LOMO МС-2 microtome

Saul
Posts: 196
Joined: Fri Jul 27, 2018 5:30 pm
Location: IL USA
Contact:

Re: DIC Question

#190 Post by Saul » Wed Jul 21, 2021 9:14 pm

BramHuntingNematodes wrote:
Wed Jul 21, 2021 6:28 pm
I guess now saul is too busy looking at everything in halo-free high contrast
Ha ha , partially true :), I made a little bit different setup, have to make normal photos of it and post it...

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#191 Post by hans » Wed Jul 21, 2021 9:14 pm

I don't any reason to doubt the final results in Rathi, most likely just a change in the 3/32" material McMaster sells (as mentioned earlier the 7/32" I have appears roughly consistent with fig. 3(b)) and maybe some of the implementation details are incorrect due to hurried (summer project) paper-writing.
Scarodactyl wrote:
Wed Jul 21, 2021 6:22 pm
Saul seems to have gotten it working, though he only posted the two pictures.
Are there any details other than these two threads?
https://www.microbehunter.com/microscop ... =6&t=11378
https://www.photomacrography.net/forum/ ... p?p=269570

I wasn't sure if that was actually DIC. I didn't see Saul claim it was, and this post seems to indicate that the splitting plane of the upper beam is not conjugate with the objective BFP?

viktor j nilsson
Posts: 760
Joined: Thu Aug 23, 2018 10:12 pm
Location: Lund, Sweden

Re: DIC Question

#192 Post by viktor j nilsson » Wed Jul 21, 2021 10:27 pm

Dmi3n wrote:
Wed Jul 21, 2021 8:09 pm
I have only one question, how to find the back focal plane?
https://www.researchgate.net/post/Is_th ... ctive_lens

The method suggested by Paolo Pozzi works really well: shine a laser pointer through the objective and measure the size of the projected image at various distances.

User avatar
Dmi3n
Posts: 121
Joined: Thu Feb 06, 2020 4:14 pm
Location: Russia, Kaliningrad

Re: DIC Question

#193 Post by Dmi3n » Wed Jul 21, 2021 11:02 pm

viktor j nilsson wrote:
Wed Jul 21, 2021 10:27 pm
Dmi3n wrote:
Wed Jul 21, 2021 8:09 pm
I have only one question, how to find the back focal plane?
https://www.researchgate.net/post/Is_th ... ctive_lens

The method suggested by Paolo Pozzi works really well: shine a laser pointer through the objective and measure the size of the projected image at various distances.
Thanks a lot, just what I needed. Time to make optical bench from Lego parts and laser pointer :D
By the way, how exactly the prism must be located in relation to back focal plane? The plane must "cut" it in two (for example for 6 mm thick prism the plane will be exactly 3 mm from the surface), or as long as the plane is just inside the prism everything will work?
Gear list:
CZJ NfPk and Polmi A w/ 45mm apo objectives, Phv, Epi Pol, trinocular
Gamma Hungary 3D-condenser
LOMO ОИ-28 Fluorescence Attachment
Set of Leitz Photar macro lens
Nikon D500 DSLR
LOMO МС-2 microtome

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#194 Post by LouiseScot » Thu Jul 22, 2021 12:39 am

hans wrote:
Wed Jul 21, 2021 9:14 pm
I don't any reason to doubt the final results in Rathi, most likely just a change in the 3/32" material McMaster sells (as mentioned earlier the 7/32" I have appears roughly consistent with fig. 3(b)) and maybe some of the implementation details are incorrect due to hurried (summer project) paper-writing.
Scarodactyl wrote:
Wed Jul 21, 2021 6:22 pm
Saul seems to have gotten it working, though he only posted the two pictures.
Are there any details other than these two threads?
https://www.microbehunter.com/microscop ... =6&t=11378
https://www.photomacrography.net/forum/ ... p?p=269570

I wasn't sure if that was actually DIC. I didn't see Saul claim it was, and this post seems to indicate that the splitting plane of the upper beam is not conjugate with the objective BFP?
Hi Hans

I'm keeping an open mind but still a bit sceptical now. The lack of anyone citing the paper and no supplementals is a concern. In principle it should work but I don't know that I'd trust the results from a 1st year student! I should mention that I've only recently been able to access Rathi's paper via the Applied Optics page as it wasn't accessible to me, although other papers from the same journal were. Previously I only had the copy that was posted on here. Saul's images look interesting but they are taken with a 20x objective so it's not clear exactly how he set things up - presumably in a similar manner to normal DIC? DIC is mediated by refractive index gradients and I couldn't really see/identify any of them in Saul's onion pics...
The DIC devil is in the details!
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#195 Post by LouiseScot » Thu Jul 22, 2021 1:00 am

Here's the Olympus Nomarski DIC setup reference, if anyone's interested:
https://www.olympus-lifescience.com/en/ ... iguration/

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#196 Post by hans » Thu Jul 22, 2021 4:16 pm

LouiseScot wrote:
Thu Jul 22, 2021 12:39 am
Saul's images look interesting but they are taken with a 20x objective so it's not clear exactly how he set things up...
I think this post is saying that the upper beam (in the slider to the left of the condenser in the first photo) goes into a slot just above the objectives where a similar 3D-printed slider containing a tube lens is shown in the first photo in this post.

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#197 Post by LouiseScot » Thu Jul 22, 2021 4:28 pm

hans wrote:
Thu Jul 22, 2021 4:16 pm
LouiseScot wrote:
Thu Jul 22, 2021 12:39 am
Saul's images look interesting but they are taken with a 20x objective so it's not clear exactly how he set things up...
I think this post is saying that the upper beam (in the slider to the left of the condenser in the first photo) goes into a slot just above the objectives where a similar 3D-printed slider containing a tube lens is shown in the first photo in this post.
Yeah but there's no detailed info about how he set up the prisms etc. Like how he got the fringes to align etc. Maybe, unlike me, he found it easy to get the patterns to match the 20x Nomarski prism! I was hoping to get a sheet of Lexan but the seller sent me Impex brand instead :( It does annoy me that Ebay sellers in the UK advertise Lexan but can't supply it..

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#198 Post by hans » Thu Jul 22, 2021 5:16 pm

LouiseScot wrote:
Thu Jul 22, 2021 4:28 pm
Yeah but there's no detailed info about how he set up the prisms etc. Like how he got the fringes to align etc.
I interpreted this as saying that the strong blue and magenta background was interference colors from the beams/polarizers, which would indicate that setup differs from normal DIC:
Saul wrote:
Tue Dec 22, 2020 3:24 pm
MichaelG. wrote:
Tue Dec 22, 2020 9:24 am
Just one thought [aside from the interesting choice of colour] ...
Did not change the color :)

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#199 Post by LouiseScot » Thu Jul 22, 2021 5:19 pm

hans wrote:
Thu Jul 22, 2021 5:16 pm
LouiseScot wrote:
Thu Jul 22, 2021 4:28 pm
Yeah but there's no detailed info about how he set up the prisms etc. Like how he got the fringes to align etc.
I interpreted this as saying that the strong blue and magenta background was interference colors from the beams/polarizers, which would indicate that setup differs from normal DIC:
Saul wrote:
Tue Dec 22, 2020 3:24 pm
MichaelG. wrote:
Tue Dec 22, 2020 9:24 am
Just one thought [aside from the interesting choice of colour] ...
Did not change the color :)
Hopefully he'll clarify at some point!
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

microb
Posts: 729
Joined: Wed Mar 27, 2019 6:39 am

Re: DIC Question

#200 Post by microb » Fri Jul 23, 2021 2:57 am

To control the strain applied and not damage the surface, wouldn’t it be better to cut the poly sheet to have supports with more surface area that a rig can make contact with. For example, instead of press point from a rod, what about spike with these blue surfaces to interface with some metal that can be accurately pressed in, maybe even torqued?
Attachments
Capture.JPG
Capture.JPG (67.56 KiB) Viewed 195501 times

tpruuden
Posts: 91
Joined: Mon Feb 22, 2021 7:44 pm
Location: Estonia/EU

Re: DIC Question

#201 Post by tpruuden » Fri Jul 23, 2021 1:08 pm

LouiseScot wrote:
Thu Jul 22, 2021 12:39 am

I don't any reason to doubt the final results in Rathi, most likely just a change in the 3/32" material McMaster sells (as mentioned earlier the 7/32" I have appears roughly consistent with fig. 3(b)) and maybe some of the implementation details are incorrect due to hurried (summer project) paper-writing.

I'm keeping an open mind but still a bit sceptical now. The lack of anyone citing the paper and no supplementals is a concern. In principle it should work but I don't know that I'd trust the results from a 1st year student! I should mention that I've only recently been able to access Rathi's paper via the Applied Optics page as it wasn't accessible to me, although other papers from the same journal were. Previously I only had the copy that was posted on here. Saul's images look interesting but they are taken with a 20x objective so it's not clear exactly how he set things up - presumably in a similar manner to normal DIC? DIC is mediated by refractive index gradients and I couldn't really see/identify any of them in Saul's onion pics...
The DIC devil is in the details!
Louise
I have no doubt, that the method works - as long one has the suitable stress gradient, this is just a question in aligning the suitable parts of the material with other optics components. Indirect proof is also the images of the material between the polarisers, as the created patterns are pretty much exactly the same as with Wollaston prisms.

What considers the polycarbonate material, it seems, that there is great variability. I have tested this far following sheet materials:

*Palsun Palram 3 mm UV
*Palsun Palram 6 mm UV
*Bayer Makrolon 6 mm UV
*Plexiglass 3 mm
*Unknown polycarbonate 3 mm

There are great variabilities in the birefringence and stress required - 6mm Palram is not creating strong gradients, requiring lot of stress, the 3mm Palram has gradient but it is shifted down like with your material is. 6 mm Makrolon seems to be the best this far. Note, that at least partially the material cut orientation seems to play significant role, see following 45/0 degree cut orientations of the 6 mm Makrolon:

https://drive.google.com/file/d/196nXwM ... sp=sharing

The dark band has shifted to one side on 0 deg cut. I have to yet test the Palsun 6 mm and 3mm in different cut orientations.
Last edited by tpruuden on Sat Jul 24, 2021 9:21 am, edited 1 time in total.

User avatar
Dmi3n
Posts: 121
Joined: Thu Feb 06, 2020 4:14 pm
Location: Russia, Kaliningrad

Re: DIC Question

#202 Post by Dmi3n » Fri Jul 23, 2021 7:08 pm

By the way, why didn't anyone thought about simply polishing that damn UV coat away with fine cerium oxide or other polish? I've heard that photographers polish away damaged lens coating from cheap lens this way and it works well.
Gear list:
CZJ NfPk and Polmi A w/ 45mm apo objectives, Phv, Epi Pol, trinocular
Gamma Hungary 3D-condenser
LOMO ОИ-28 Fluorescence Attachment
Set of Leitz Photar macro lens
Nikon D500 DSLR
LOMO МС-2 microtome

tpruuden
Posts: 91
Joined: Mon Feb 22, 2021 7:44 pm
Location: Estonia/EU

Re: DIC Question

#203 Post by tpruuden » Fri Jul 23, 2021 8:46 pm

There is no visible coating, it is more of co-extrusion and mixed in additives.
Dmi3n wrote:
Fri Jul 23, 2021 7:08 pm
By the way, why didn't anyone thought about simply polishing that damn UV coat away with fine cerium oxide or other polish? I've heard that photographers polish away damaged lens coating from cheap lens this way and it works well.

tpruuden
Posts: 91
Joined: Mon Feb 22, 2021 7:44 pm
Location: Estonia/EU

Re: DIC Question

#204 Post by tpruuden » Mon Jul 26, 2021 8:46 am

Quick low quality image through eyepiece, this is with one Sanderson prism after 50x objective and thin plastic film bottom sample holder - this is now PlasDIC recreation? I was unable to get it working reasonably with lower magnifications.
https://drive.google.com/file/d/1EHKyCn ... sp=sharing

I do not have full DIC setup to compare with but it seems something similar to weak DIC 3D effect is seen with just aligning the suitable areas of the stressed polycarbonate, even if the gradients are not exactly the same. This is cheek cells with two stressed polycarbonate pieces and crossed polarisers dropped to Leica beam path:
https://drive.google.com/file/d/1qBqUfW ... sp=sharing

tpruuden
Posts: 91
Joined: Mon Feb 22, 2021 7:44 pm
Location: Estonia/EU

Re: DIC Question

#205 Post by tpruuden » Mon Aug 02, 2021 5:51 pm

Well, this is interesting - all windows are from THE SAME material. Wisely I marked the cut orientations on the protection film, that was removed... The square stress gradient piece can apparently be used on "sideways" orientation also.
https://drive.google.com/file/d/19ivjLl ... sp=sharing

Just for kicks - attempt to create the gradient directly in Leica condenser turret:
https://drive.google.com/file/d/19sVOjf ... sp=sharing

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#206 Post by hans » Tue Aug 03, 2021 7:05 pm

tpruuden wrote:
Mon Aug 02, 2021 5:51 pm
Wisely I marked the cut orientations on the protection film, that was removed...
What is the orientation of the beam relative to the original sheet in those three examples?

tpruuden
Posts: 91
Joined: Mon Feb 22, 2021 7:44 pm
Location: Estonia/EU

Re: DIC Question

#207 Post by tpruuden » Tue Aug 03, 2021 10:43 pm

hans wrote:
Tue Aug 03, 2021 7:05 pm
What is the orientation of the beam relative to the original sheet in those three examples?
I believe the centered dark band version to be 45 degrees cut. I have to remove stress frames and check over other versions, as the mishap with markings happened.

hans
Posts: 986
Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: DIC Question

#208 Post by hans » Wed Aug 04, 2021 4:56 am

Ah, missed what you were saying about the protective film... so they are cut at 0, 45, and 90 degrees but not sure which is which?

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#209 Post by LouiseScot » Wed Aug 04, 2021 12:50 pm

I was wondering if anyone could point me in the right direction as to where to buy a Nomarski prism set i.e. a condenser prism (are they all the same?) and, say, a 20x objective prism? Possibly new ones but depends on the price ;) I see various prisms on Ebay UK but it's not clear (to me) what's what.
I'm otherwise still busy with other things but hope to be back on the case by the end of the month :)

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: DIC Question

#210 Post by LouiseScot » Wed Aug 04, 2021 6:03 pm

Thorlabs sell DIC prisms but, of course, everything from them is expensive! A Nikon N2 Condenser prism is about £908 with tax and a 20x prism slider is the same. So starter Nomarski DIC parts for £1800.... Tempting. If anyone knows of another source for less, I'd obviously be interested :) Maybe there's a cheap Chinese source?

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Post Reply