mnmyco wrote: ↑
Sun Sep 22, 2019 9:07 pm
Thanks. I was guessing it was newer than my 1242. Do you know a turret model 1986? No number on the condenser but it looks similar to a 1242. I will try to find the posting again.
It's older. It's the condenser design from the very first AO phase microscopes. 1946 or something like that to 1961 or so.
So, when AO built the first phase system for the infinity series scopes, they built two phase annuli housings and 3 different condensers. The two phase housings were the #1240 which is a rotary carousel type and can accomodate up to 4 phase annuli and the #1241, which takes only a single phase annulus. Each can be fitted with one of three condenser lens packs, #1242 standard working distance, #1243 intermediate w.d. and # 1244 long w.d. The annuli used with the 1242 and 1243 are the standard w.d. annuli. To use the # 1244 condenser, there were only 2 long w.d. annuli , for the 10X and the 20X objective.
Later, as the system evolved there was another long w.d. annulus for the 45X long w.d. objective released and a set of intermediate w.d. annuli, designed to be used with a standard w.d. condenser. In other words, the intermediate w.d. condenser was dropped from the system.
Only the # 1240 condenser carousel( or single annulus condenser) can be used in a series 10 or 20 because of the dovetail and height requirements.
Condenser carousels # 1205 and 1830 are superficially similar but have the different dovetail used on the series 100 , 400 and then the unique 1800( inverted), microscope, respectively. #1205 condenser carousels are usually fitted with the # 1201 .90 achromat aplanat condenser lens packs, used for standard and intermediate w.d. The # 1202 condenser lens pack is for l.w.d.
The # 1830( sometimes referenced as 1835?) condenser carousel, is identical to the # 1205, except for the dovetail and the annuli it would normally be fitted with( l.w.d.). The standard condenser lens pack it was fitted with, sometimes does not have a separate cat.# on it. The unit is usually referred to as the 1830 condenser. There is a # 1865 condenser lens pack that is a longer w.d. condenser , which is somwtimes fitted into the #`1830 housing.
I do not know the # 1986 that you refer to. It is possible that it is for the Leica ATC 2000 microscope, which Leica produced in Buffalo, as a student microscope to replace the 150. The ATC 2000 used modified D.I.N. achromats and planachros, similar in construction to those of the Reichert series 400 , badged Leica. Other fittings were similar too, like the phase carousel, sometimes painted grey instead of black. I do not know what numbering scheme they used on the ATC 2000 but the dovetail is the later one used on the 100 and 400 series.