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Cor
2-Mar-2016, 02:37
I just obtained a "new" lens, a Geronar 300mm f9 which has a tiny chip (missing a half moon shaped 1 mm wide chip) at the edge of the rear element. This was fully disclosed by the seller, no surprise here.

I was just wondering how much effect, if all, it has: The Geronar is stated to have a coverage of 340mm, and I will use it on my 4*5. Can I assume that this chip might influence the projected image only at the edge of the cover circle, so no problem for 4*5 ?

Or is this is a too simple reasoning ?

best,

Cor

Peter De Smidt
2-Mar-2016, 03:06
You may consider darkening the chip. That out to minimize any flare (or other issues) caused by it.

Lachlan 717
2-Mar-2016, 03:12
None.

Steven Tribe
2-Mar-2016, 05:01
Absolutely no effect - other than when you sell it.

Cor
2-Mar-2016, 06:01
Absolutely no effect - other than when you sell it.

Or bought it..:)..

Thanks for reassuring me, guys.

A bit related question, mostly out of curiosity;

I found somewhere that the Geronar is of relative simple design: 3 elements in 3 groups (3/3), but I cannot find any drawing scheme such as shown here (http://www.prograf.ru/rodenstock/largeformat_en.html#table1) for the modern Rodenstock lenses.

It looks like the rear element is one piece of glass, so the front element consists of 2 piece with air in between I assume ?

thanks,

Cor

B.S.Kumar
2-Mar-2016, 07:30
Absolutely no effect - other than when you sell it.

Tell me about it :)

Glad you're relieved, Cor!

Kumar

Cor
2-Mar-2016, 07:52
No problem, Kumar, wasn't too worried in the first place, always a pleasure dealing with you, your description of items, communication and packaging are first rate !

Thanks,

best,

Cor

..ps anybody knows a lead to an internet page with a drawing of the 3/3 Geronar ?


Tell me about it :)

Glad you're relieved, Cor!

Kumar