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crainier Joined: 20 Jun 2010 Posts: 4 |  Posted: Sun Jun 20, 2010 10:20 am Post subject: Lens Questions on Speed Graphic
I am considering buying a 165mm f2.7 Zeiss Tessar lens. Does anybody know if it will fit onto a standard Speed Graphic lens board or does it need a specialized mount? Also with this lens can I get the same shallow focus effect and color as a Kodak Aero-Ektar 178MM F2.5 lens..
Thank-you!
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Les Joined: 09 May 2001 Posts: 2682 |  Posted: Sun Jun 20, 2010 10:36 am
I've never seen an f2.7 Tessar, but I have a 152mm F2.7 B&L Baltar lens in barrel that needed a special lens board, so I'd have to assume yours will too.
Since depth of field is dependent on subject distance, yes this 2.7 Tessar would give you the same depth of field as the aero Ektar would. That said, the characteristics of the out of focus image and the sharpness of the infocus image might differ quite a bit.
A relatively sharp but low contrast lens will appear to have a greater depth of field because the human will have a harder time discerning the point where the in focus image meets the out of focus area. Where as a brutally sharp, high contrast lens will appear to have less depth of field. |
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45PSS Joined: 28 Sep 2001 Posts: 4081 |  Posted: Sun Jun 20, 2010 9:52 pm
from the Vademecum:
1926
Tessar f2.7 It was made in 15-165mm in 11 foci in 1926.
It was noted as 2in =5cm for 1x0.75in movie; 3in or better 3.125in = 8cm for VP; 4in or 4.75in for 6x9cm;
5.75in for 1/4plate; 6.0in or 6.5in for 5x4in, 7in =18cm for 5.5x3.25in and 8.25in = 21cm for 6.5x4.75in.
This Tessar was for cine+press use. They were later made in 0.375in (9mm) to 8.5in in 15 sizes in 1929). The
coverage in B.J.A. 1926, p658 seems the same for the Tessar f2.7 as for the Triotar f3.5 and f3.0 and they are
all tabled up together.
The central image was good enough to allow it to continue as a cine lens
into the 1930's, but the design seemingly was revised for the Movikon 16mm as it seems there is a Patent for
a reversed Tessar f2.7 for 45°at that period.(USPat 1,826,362). |
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