Short(kurz) and Long(lange) barrel Jena eyepieces(Okulare) ?

[kalleboy]

Hello (Sie können die Antwort in Deutsch schreiben)
There are short and long barrel versions of Zeiss Jena DDR 1970-1980 eyepieces
- What is the difference in them ?
- Why two variation types ? Why ?
- Since these are 40 years old...No brochures are available that tell what they are and it is very frustrating :-(
- Are the long ones for visually challenged eyeglass people ?
- Which is combatible with my Laboval 2 DDR Jena, 1980 ? Now it has short A10x(14) eyepieces.

[Werner]

All (Huygens) oculars with lower magnification (<=10) need lenses with large focus and therefore a longer distance between the lenses. The 5x ocular is the longest.
Oculars above 10...12,5 have shorter distance in cause of the shorter focus.
Ramsdenoculars are shorter as the Huygenstype, the pictureplane is outside the lenses, the lenses are mounted closer.

Have a look at wikipedia "eyepiece".

regards   -   Werner

[kalleboy]

But I have seen like:
- Both Jena short and long 5X eyepieces
- Both Jena short and long 10x eyepieces
- ...and so on
Are short ones more advanced technology or newer ?
Or are the long ones for eyeglasses for longer eyerelief ?

[Walter P.]

Hi Kalle,

On CZJ eyepieces you can find the following engraving:

"A".....is for incident light microscopes. You can use them also for objectives with low magnivication and color aberration
"K".....this eypieces correct the color aberration of the objectives
"P".....this eypieces plane the picture of is objectives with corrected color aberration (M25 worm).
"PK"...this eyepieces correct the color aberration of the objektiv and plane the picture.
"w"....this stands for "wide". Ordinar the plug in diameter is 23,2 mm. For "w" eypieces the diameter is 30 mm.
"m"...is on PK 12,5 m (16) eyepieces. They are made for the Amplival pol microscope.

Best regards
Walter

[kalleboy]

OK. I found and ordered PK6,3x(19) at ebay.com to replace A10x(14).(When available will buy PK5x)
- Costed 30€. Expensive.
- Since people say PK(Jena) is the best I hope to get superb pictures with it.
- Also better for coin viewing now zoom is 3,2x*6,3x=20,16x (Before 3,2x*10x=32x)
- How much better colors and image I can now achieve with the new PK comparing A ?

[rhamvossen]

Hi Kalle,

You seem to take it for granted that people answer your numerous questions. A simple "thank you" once in a while would be appropriate.

Rolf