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View Full Version : All those Docter Germinar lenses ...



Matus Kalisky
20-Sep-2007, 01:07
Hi, the only purpose of this tread is to provoke all those lens experts around ;)

Well - until recently it seemed that there were basically two types of Germinar lenses:
- Germinar W - with large coverage of ~ 70 deg (or more)
- Apo Germinar - with coverage of about 45 deg.

But recently also a 'Apo Germinar W' appeared ( 150/8 (http://cgi.ebay.de/MINT-Docter-150mm-f8-Apo-Germinar-W-MC-Lens-Copal-1-4x5_W0QQitemZ280151042552QQihZ018QQcategoryZ30076QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) and 240/8 (http://cgi.ebay.de/Docter-240mm-f8-Apo-Germinar-W-Lens-8x10-Center-Filter_W0QQitemZ280151045852QQihZ018QQcategoryZ30076QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) ) which seem to be of different optical contruction (8/8) and have different coverage each. There are 63 deg claimed for the 150 and 73 deg for 240.

So - what is your knowledge about these lenses? Are there any other Germinar lens types? I am jut curious.

P.S. please note that I have no relation to the seller and I point to his auctions only as to a source of information.

Arne Croell
20-Sep-2007, 04:27
No, there were always more than the 2 types you mention. Actually, the Apo-Germinar W is older than the Germinar W, developed by Zeiss Jena. Here is an excerpt from the article on Docter lenses I wrote for View Camera:

"Apo-Germinar W
These are the same symmetric wide-angle process lenses as their Carl Zeiss Jena counterparts, developed in 1981, with eight elements in eight groups. Supposedly these lenses were developed (in the GDR) to represent the state of the art without regard for the cost involved, and were quite difficult to manufacture. The optimum aperture for the Apo-Germinar W is f/16 and they are multicoated. Again, the image circles in table 3 are for 1:1 reproduction ratio and the image circle diameter at infinity should be about half that value. Similar to the Apo-Germinars, below are the values for the infinity im-age circle provided by Docter:

Apo-Germinar W 8/150mm: 184mm (63)
Apo-Germinar W 8/210mm: 276mm (66.5)
Apo-Germinar W 8/240mm: 352mm (72.5)

In this case, the numbers of the officially stated angles of coverage and the image circles at infinity actually do agree.

The initial appeal of the Apo-Germinar Ws suffers from the large size and weight when compared to modern Plasmats, which have similar coverage. A look at their MTF curves, however, shows that the evenness of the resolution and contrast over the field at 1:1 is superb for such a large angle of coverage. For instance, for the 240mm lens the MTF curves are significantly higher towards the edges of the field than those of an Apo-Gerogon or a G-Claron of the same focal length. So for reproduction and close-up photography in the studio, or for enlarging they might be the perfect choice."

The Germinar W was developed in the mid-1990's by Docter. The Apo-Germinar-W is really much larger - the 240mm f/8 one is about the size of an f/5.6 360mm Plasmat type.
There were also Germinar-S (for specialty) and Germinar-K (for copiers) lenses.

Arne Croell
20-Sep-2007, 14:07
A short addition: The Zeiss Jena version was only available in barrel. The Docter version was available both in shutter and in barrel.

rob
20-Sep-2007, 15:24
Oh, No, I don't need another 150 and 240 Docters ;)