LWD Optosigma objectives.

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

Moderators: Pau, rjlittlefield, ChrisR, Chris S.

Yawns
Posts: 399
Joined: Sun Dec 20, 2015 9:18 am
Location: Benavente, Portugal

LWD Optosigma objectives.

Post by Yawns »

Does anyone have experience with these lenses? .. the price seems to be too good ... and I can't find any information / analysis / comment ...

searches here on the forum do not return anything except posts where Optosigma material is referred to ... stages ... nothing about the lenses.


https://europe.optosigma.com/long-worki ... -5177.html

Thank you.
António
YAWNS _ (Y)et (A)nother (W)onderful (N)ewbie (S)hooting

RobertOToole
Posts: 1692
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Re: LWD Optosigma objectives.

Post by RobertOToole »

Yawns wrote:Does anyone have experience with these lenses? .. the price seems to be too good ... and I can't find any information / analysis / comment ...

searches here on the forum do not return anything except posts where Optosigma material is referred to ... stages ... nothing about the lenses.


https://europe.optosigma.com/long-worki ... -5177.html

Thank you.
António
Hi António,

I've looked at these before and cosmetically they look good but the lens datasheet only has a % transmission graph. Nothing about CAs other than "Chromatic aberration is corrected in the visible range (400 − 700nm)".

Thorlabs objectives are complete with graph axial color and lots of other data. You would think they would show how well they are corrected if had something to brag about, so judging by the price I would say they are not really APO corrected.

Hopefully someone with some first hand experience will post.

Best,

Robert

Chris S.
Site Admin
Posts: 3579
Joined: Sun Apr 05, 2009 9:55 pm
Location: Ohio, USA

Post by Chris S. »

Note, too, that the numerical apertures are small for a couple of the lenses. The 20x has NA 0.30 (more normal for a 10x); the 50x has NA 0.42. As we know, lower NA means lower resolution.

--Chris S.

Yawns
Posts: 399
Joined: Sun Dec 20, 2015 9:18 am
Location: Benavente, Portugal

Post by Yawns »

Thanks .. yes I am also suspicious .. even because I can't find any other references to the lenses .. I only saw them because I went to their website to check the specifications of a pair of goniometers and a rotation stage of the brand I bought on eBay.
Thank you
YAWNS _ (Y)et (A)nother (W)onderful (N)ewbie (S)hooting

Yawns
Posts: 399
Joined: Sun Dec 20, 2015 9:18 am
Location: Benavente, Portugal

Post by Yawns »

Chris S. wrote:Note, too, that the numerical apertures are small for a couple of the lenses. The 20x has NA 0.30 (more normal for a 10x); the 50x has NA 0.42. As we know, lower NA means lower resolution.

--Chris S.

I noticed that too, but I always thought it was a "normal" value for this type of long distance inspection lenses ...

Always puzzled me why Mitutoyo M plan APO have so low NA values ... well bellow Nikon or Olympus Fluorite lenses. Mitutoyo 10X 0.28 is below an FL, which usually has an NA of 30 ...

that part I thought it was " normal". The Optosigma 10x is 0.30 .. the Mitutoyo M plan is only 0.28...
YAWNS _ (Y)et (A)nother (W)onderful (N)ewbie (S)hooting

Scarodactyl
Posts: 531
Joined: Sat Apr 14, 2018 10:26 am

Post by Scarodactyl »

Maybe rebranded Chinese mitutoyo clones?
Edit:it must be. Here is one from bolioptics. The picture is a little different and says 10x/.28 but the specs say .30 https://bolioptics.com/10x-infinity-cor ... nce-6-4mm/
The lowe NA variants are copies of the mititoyo super long working distance line which are not great for photography.
I wouldn't waste time on it.
Last edited by Scarodactyl on Thu Jan 23, 2020 7:34 am, edited 1 time in total.

lothman
Posts: 507
Joined: Sat Feb 14, 2009 7:00 am
Location: Stuttgart/Germany

Post by lothman »

Yawns wrote:
Always puzzled me why Mitutoyo M plan APO have so low NA values ... well bellow Nikon or Olympus Fluorite lenses. Mitutoyo 10X 0.28 is below an FL, which usually has an NA of 30 ...
Yes but look at the huge working distance of the Mitutoyos compared to other lenses. If you will keep NA but increase the working distance, the lens diameter has to become bigger, what makes lens usually much more expensive.

Providing a good working distance and somehow high NA makes the Mitutoyo well regarded for industrial use (where you have to measure in the bottom of a groove and there need high working distance). On a biological microscope you usually can keep the working distance very small and therefore have lens designs with high NA but small working distance.

Adalbert
Posts: 1255
Joined: Mon Nov 30, 2015 1:09 pm

Post by Adalbert »

Hello everybody,
I have Mitty 10x / 0.28 and Lu Plan 10x / 0.30
Lu Plan produces more CA than Mitty !
BR, ADi

Scarodactyl
Posts: 531
Joined: Sat Apr 14, 2018 10:26 am

Post by Scarodactyl »

Lu is a nikon plan fluor, right? It should be less corrected than an apo.

Adalbert
Posts: 1255
Joined: Mon Nov 30, 2015 1:09 pm

Post by Adalbert »

Hello Scarodactyl,
Yes, all my lenses from NIKON (Lu Plan 5x, 10x, 20x) produce much more CA than Mitties :-(
BR, ADi

RobertOToole
Posts: 1692
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

Adalbert wrote:Hello Scarodactyl,
Yes, all my lenses from NIKON (Lu Plan 5x, 10x, 20x) produce much more CA than Mitties :-(
BR, ADi

Just FYI if anyone is curious:

Nikon LU Plan 10X vs Nikon CFI Plan Achromat 10x 0.25 vs
Mitutoyo M Plan Apo 10X 0.28 vs Nikon 10x 0.20 MM:

https://www.closeuphotography.com/10x-lens-test

Also

Mitutoyo M Plan Apo 5X/0.14 vs Nikon CFI LU Plan Fluor 5X/0.15 vs Mitutoyo M Plan Apo 7.5X/0.21 Objective @ 5x vs others:


https://www.closeuphotography.com/5x-lens-test


Image

Adalbert
Posts: 1255
Joined: Mon Nov 30, 2015 1:09 pm

Post by Adalbert »

Hello Robert,

I would recommend the Lu Plans if someone wants to learn how to remove the CA from the stacks :-)

Some years ago they were extremely cheap, so I made some good bargains but I had to learn how to manage the problem of the CA :-(

BTW, but since I have had the Mitties I have been using only Mitties :-)

BR, ADi

RobertOToole
Posts: 1692
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

Adalbert wrote:Hello Robert,

I would recommend the Lu Plans if someone wants to learn how to remove the CA from the stacks :-)

Some years ago they were extremely cheap, so I made some good bargains but I had to learn how to manage the problem of the CA :-(

BTW, but since I have had the Mitties I have been using only Mitties :-)

BR, ADi

This is the same case here ADi, I usually reach for the Mitutoyo in most cases, they are sharp, well balanced with a good image circle.

I only wish I knew then, what I know now about Mitutoyo, I would have saved myself a ton of money and time. :shock:

I have too many Nikon objectives sitting here with a layer of dust on them :shock:

This is why I decided to create my site and I'm really glad I did, even though it has taken lots of time.

Best,

Robert

Scarodactyl
Posts: 531
Joined: Sat Apr 14, 2018 10:26 am

Post by Scarodactyl »

Does nikon make a lwd apo series? I'd figure they would have to but I bet they cost a lot more than a mitutoyo. Again it's pretty clear a nonapo isn't likely to beat out an apo (of equivalent tier and vintage anyway) on ca. My normal nikon 20x apo is extremely well corrected as far as I can tell, but that must be easier without the constraint of a long working distance.

RobertOToole
Posts: 1692
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

Scarodactyl wrote:Does nikon make a lwd apo series? I'd figure they would have to but I bet they cost a lot more than a mitutoyo. Again it's pretty clear a nonapo isn't likely to beat out an apo (of equivalent tier and vintage anyway) on ca. My normal nikon 20x apo is extremely well corrected as far as I can tell, but that must be easier without the constraint of a long working distance.
As far as I am aware, there are no APO ELWD or SLWD, the longer the WD the less corrected for CAs generally speaking. MM objectives have super WD but the they are also the least corrected for CAs.

You are pretty much right on objectives and APO labels but that's not the case with consumer and industrial lenses, some non-APOs are much better corrected for CAs vs APO labeled lenses, like the Tominons or Noritsu lenses are good examples of well corrected without an APO label. :D

Best,

Robert

Post Reply Previous topicNext topic