Hi,
I am considering buying a Lomo 70x/1.23 water immersion objective (parfocal length:32.7mm) to use with a Nikon Labophot 2 scope.
Am I right that I need a 12mm parfocal extender to make it parfocal with my other objectives? Does the extender need to have some lens in it or is a hollow one fine? Reading various threads on the topic did not clear my doubts on the latter issue.
Many thanks in advance,
Giulio
Parfocal extender
Re: Parfocal extender
If you add 12mm extension to a NA1.23 objective performance will suffer, still my be worth trying. Would be better to add such extender to low NA objectives, no more than NA0.30 or so. This thread at Photomacrography.net talks about it
I do not think there are parfocal extender with lenses, there are intermediate tubes with lenses that extend the whole system
I do not think there are parfocal extender with lenses, there are intermediate tubes with lenses that extend the whole system
Re: Parfocal extender
Thanks! I was not aware of the issue. I might want to use the shortest extender I may get away with. Not parfocal, but as long as it allows me not to have to modify the stage...
The Plezy extenders mentioned here https://www.microbehunter.com/microscop ... php?t=2396 seem to have some glass in them, though I was confused about what they achieved since the poster mentioned the need to use a glassless extender in addition
The Plezy extenders mentioned here https://www.microbehunter.com/microscop ... php?t=2396 seem to have some glass in them, though I was confused about what they achieved since the poster mentioned the need to use a glassless extender in addition
Re: Parfocal extender
The Zeiss West DIC sockets add ca. 12mm length and have lens to compensate for this extension. Not fully parfocal but close.
Re: Parfocal extender
Giulio,
I have used those short 32.7mm LOMO objectives on Nikon Labophot 2 and Optiphot 1.
I usually have a full turret of 5 short LOMO apo objectives on the same turret. Instead of using parfocal extenders (which significantly degrades high NA objective performance), I raised up my Labophot / Optiphot 's stage by 13-14mm, using 4 machine screw nuts and extra long screws. I also raised my condenser 13-14mm.
Here is my chronicle: http://www.photomacrography.net/forum/v ... lomo+screw
Briefly, I used M4-0.70 x 30 screws for stage holder and put 3 hex nuts ( either #8-32 or #10-24, I don't remember which) under the stage to raise it 13-14 mm.
As to how to raise your condenser: it depends on which condenser you have. I have not owned any Nikon condenser but have always been able to adapt 3 part condensers to Nikon using Nikon condenser dovetail adapter and Legos. In the following thread you will find a photo posted by me showing how I adapted a Leitz condenser to Optiphot:
https://www.microbehunter.com/microscop ... =5&t=12243
I have used those short 32.7mm LOMO objectives on Nikon Labophot 2 and Optiphot 1.
I usually have a full turret of 5 short LOMO apo objectives on the same turret. Instead of using parfocal extenders (which significantly degrades high NA objective performance), I raised up my Labophot / Optiphot 's stage by 13-14mm, using 4 machine screw nuts and extra long screws. I also raised my condenser 13-14mm.
Here is my chronicle: http://www.photomacrography.net/forum/v ... lomo+screw
Briefly, I used M4-0.70 x 30 screws for stage holder and put 3 hex nuts ( either #8-32 or #10-24, I don't remember which) under the stage to raise it 13-14 mm.
As to how to raise your condenser: it depends on which condenser you have. I have not owned any Nikon condenser but have always been able to adapt 3 part condensers to Nikon using Nikon condenser dovetail adapter and Legos. In the following thread you will find a photo posted by me showing how I adapted a Leitz condenser to Optiphot:
https://www.microbehunter.com/microscop ... =5&t=12243