mike_foster

Paul,

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Which roll film back do you use for 6x12? I thought that 6x12 backs

did not work with 220 roll film.

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Thanks.

Hi,

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I want to start out in large format photography in 6x9 format using a roll film back. I am now at a stage of choosing lenses and have been looking for the ultimate lenses. Since I will be shooting a relatively small format, lens performance will be vital to me. I want to get the best lenses and not want to look back and wonder if I made the right choices.

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Anyway I am now looking at the range of Rodenstock �Digital� lenses. I want to share some information about them and also hopefully get some input from shooters (if any) who use these lenses.

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These lenses do seem incredible. Despite their name they are regular large format lenses in Copal shutters. They are not for 4x5 shooters since the largest image circle is 150mm.

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They come in three different designs. The first is the Apo-Sironar Digital. The second is the Apo-Sironar Digital HR and the last is the Apo-Macro-Sironar Digital.

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Sadly the Rodenstock brochure on these lenses is very poor. It is very confusing and there is little useful information on them. There is an MTF chart on only one of the lenses, the Apo-Sironar HR 60mm. But that MTF chart is VERY impressive. If that chart is true then this lens is the sharpest lens, period. It has an even better MTF curve than the Zeiss Planar 50/1.4 for the 35mm Contax cameras. And that lens is regarded by many as the sharpest ever.

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But sadly, this lens or the other two from that HR series, the 35mm and 100mm are useless for me since their image circles are only 70mm. However I read that at the recent Photokina show they introduced two more lenses in the HR series. Does anyone know much about them? What their image circles are?

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But the question remains about the MTF curves of the other lenses. Why did they not publish it in the brochures? Very frustrating.

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Here is more confusion. In one brochure the Apo-Sironar Digital is listed has having 7 elements in 5 groups. Yet the other brochure says 8 elements in 6 groups. In one brochure the coverage for 90mm lens is shown as 140mm and in the other it is listed as 125mm.

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Another confusing thing. There are 8 lenses in this series from 35mm all the way to 180mm. One would expect the image circle, weight and price to rise proportionally with the focal length as is the custom. But it does not! The 105mm (170g) weighs less than half as the 90mm (460g)! It also costs almost half as much! Why? The image circle for both is listed as 125mm. Image circles do rise with the focal lengths but not proportionally.

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The bottom line. If the MTF curves of all the lenses are as good or even close to the one they print (the 60mm HR) then these are truly amazing lenses.

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If only I could get more information on them!!!