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110mm f2.8 LS Schneider Kreuznach lens for Phase XF

algrove

Well-known member
I am trying to determine if the angle of view is correct for the 110 LS SK blue line lens. Brochures point to 29 degrees with the 150 being 26 degrees. The 110 is a 35mm equivalent of 68mm and the 150 is a 35mm equivalent of 93 mm. It jsut seems that the advertized 3 dgrees differential between these 2 lenses is very close compared to the 40mm difference in FL.

Lens tables suggest that a 70mm 35 equivalent lens is 34 degrees angle of view which to me might make the 110 around 33 or 32 degrees angle of view instead of the 29 suggested by Phase advertising literature.

Anyone out there with the 110 lens who might know yhe answer and what the real angle of view would be for this lens?
 

Bill Caulfeild-Browne

Well-known member
Hmmm... interesting! My 120 LS is listed at 33 degrees so I would have thought the 110 would be closer to 31 or 32, as you say. I don't own that lens so I can't give more info. Also, because the close focus is so different between the two lenses, looking at the area covered isn't helpful.
 

ondebanks

Member
I am trying to determine if the angle of view is correct for the 110 LS SK blue line lens. Brochures point to 29 degrees with the 150 being 26 degrees. The 110 is a 35mm equivalent of 68mm and the 150 is a 35mm equivalent of 93 mm. It jsut seems that the advertized 3 dgrees differential between these 2 lenses is very close compared to the 40mm difference in FL.

Lens tables suggest that a 70mm 35 equivalent lens is 34 degrees angle of view which to me might make the 110 around 33 or 32 degrees angle of view instead of the 29 suggested by Phase advertising literature.

Anyone out there with the 110 lens who might know yhe answer and what the real angle of view would be for this lens?
The brochures are in error. Using the exact FOV formula for rectilinear lenses, for a 150mm lens, I get 25.3 degrees on the 60/80 MP Phase backs, and 26.2 degrees on 645 film. So they must be using 645 film as the reference dimension, not their larger digital backs. The same figures for a 110mm lens are 35.2 degrees (645 film) and 34.0 degrees (60/80 MP back).

BTW you reckoned in the wrong direction - the 68mm-equivalent lens is shorter than the 70mm-equivalent, so its FOV will be slightly wider than 34 degrees, not narrower.

Ray
 
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