Zeiss 'Achrostigmat' 44 01 51

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
Post Reply
Message
Author
MichaelG.
Posts: 1495
Joined: Mon Apr 10, 2017 8:24 am
Location: NorthWest England

Zeiss 'Achrostigmat' 44 01 51

#1 Post by MichaelG. » Mon Sep 17, 2018 8:41 pm

This is turning out to be a mystery !

Wanting to experiment with the combination of an 'infinity' objective and my camera lens, I purchased [at a reasonable price] a 40x/0.65 Ph 2 Achrostigmat, for use with 0.17 coverslip

Phase is also indicated by green text
40x is also indicated by a pale blue ring

To my surprise, however; there is a white ring on the nose, which would normally indicate 'water immersion' ... but there is no text to support that.
Zeiss objective identifiers
Zeiss objective identifiers
IMG_2283.JPG (96.77 KiB) Viewed 1297 times
Strangely, Zeiss seems to have disowned this range of 'budget-priced' routine achromatic objectives ... one of the very few references I have found is in 'Microscopy from the very beginning':
Achrostigmat [my underlining]
Achrostigmat [my underlining]
IMG_2289.JPG (435.01 KiB) Viewed 1297 times
Can anyone tell me more, please ?

MichaelG.
.

P.S. Yes I am aware that an achromat is not really suited to photographic use ... this is just a first experiment.
Too many 'projects'

Charles
Posts: 1108
Joined: Mon Mar 02, 2015 11:55 pm

Re: Zeiss 'Achrostigmat' 44 01 51

#2 Post by Charles » Mon Sep 17, 2018 9:34 pm

I would think anything immersion would have a higher NA than 0.65.

Is there a picture?

MichaelG.
Posts: 1495
Joined: Mon Apr 10, 2017 8:24 am
Location: NorthWest England

Re: Zeiss 'Achrostigmat' 44 01 51

#3 Post by MichaelG. » Mon Sep 17, 2018 9:54 pm

Charles wrote:I would think anything immersion would have a higher NA than 0.65.

Is there a picture?
If you think it will help, I will gladly photograph it tomorrow
... I'm writing this in bed.

But I think I have listed everything

The mystery [apart from why Zeiss no longer mentions them] is:
If it is not Water Immersion, why does it have a white ring ?

MichaelG.
.

Edit: As an interesting aside: Here is the non-phase version 44 01 50
https://www.ebay.com/itm/Zeiss-40x-0-65 ... 2144219357
Rather worryingly [but unsurprisingly]: The ring looks grey or white according to the lighting.
:? ... Perhaps grey means 'non-immersion' but Zeiss doesn't list that as a code.
Too many 'projects'

Charles
Posts: 1108
Joined: Mon Mar 02, 2015 11:55 pm

Re: Zeiss 'Achrostigmat' 44 01 51

#4 Post by Charles » Mon Sep 17, 2018 10:52 pm

No idea. I know on the finite achrostigmat ones they had a cap that went on the end of the objective. It doesn't look like it is flush to the surface of the metal. Maybe that white ring holds a cap on?

Edit: Or maybe I'm thinking of an antiflex cap going on top?

MichaelG.
Posts: 1495
Joined: Mon Apr 10, 2017 8:24 am
Location: NorthWest England

Re: Zeiss 'Achrostigmat' 44 01 51

#5 Post by MichaelG. » Mon Sep 17, 2018 11:11 pm

Thanks, Charles

Frankly ... I'm now guessing that my 'white' ring is actually 'grey' and means non-immersion.

MichaelG.
.

Update: Viewed in the daylight, I am convinced that the ring is pale grey.
... and it seems reasonable to assume that this means non-immersion.
[ some documentary evidence would be nice though ]
Too many 'projects'

Hobbyst46
Posts: 2165
Joined: Mon Aug 21, 2017 9:02 pm

Re: Zeiss 'Achrostigmat' 44 01 51

#6 Post by Hobbyst46 » Tue Sep 18, 2018 8:37 am

Indeed it is hard to find a description of the "Achrostigmat" in Zeiss literature.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

photomicro
Posts: 129
Joined: Thu Aug 03, 2017 10:28 am
Location: UK

Re: Zeiss 'Achrostigmat' 44 01 51

#7 Post by photomicro » Tue Sep 18, 2018 9:52 am

In the Axioskop 20 brochure, dated 1990, it describes the ICS optics, and includes the following;

"The Achrostigmat objectives: the economical objectives for transmitted-light microscopy. With bright image and good resolution. True-to-color images due to excellent chromatic correction. Astigmatism has been eliminated. Their sturdy front lenses make the Achrostigmat objectives suitable for routine work"

When you read this sort of froth, makes you wonder why they bothered with the better ranges!

Your 40/0.65 Ph 2 is listed, and illustrated, in black, with green lettering. It has a powder blue ring on the main barrel, and a lower pale ring nearer the end. There is no WI item listed.

As I understand it with this system, the tube lens used is part of the correction system, making the intermediate image fully corrected so that non-corrected eyepieces can be used. However, this might mean it isn't ideal for use off a Zeiss stand.

I had this brochure with me on Saturday Michael... :)

MichaelG.
Posts: 1495
Joined: Mon Apr 10, 2017 8:24 am
Location: NorthWest England

Re: Zeiss 'Achrostigmat' 44 01 51

#8 Post by MichaelG. » Tue Sep 18, 2018 2:34 pm

Many thanks, Mike

That certainly seems to support my assumption that the pale grey ring means 'non-immersion' [dry], but I have yet to find any documentary evidence ... The Zeiss 'key' that I posted yesterday omits any reference to a grey ring.

My intention is to see how it performs with the Lumix G1 45-200mm zoom serving as the 'tube lens' cum 'relay lens' ... It might be a disaster, but who knows !?!

MichaelG.
Too many 'projects'

Post Reply