View Full Version : 100mm 5.6 vs 90mm f4.5 - Same Angle of View?

William D. Lester
3-Nov-2004, 12:50
I own a Rodenstock 90mm f4.5 Grandagon N with a 105deg. angle of view. It is a fairly large and hefty piece of lens. The Schneider 110mm f5.6 SS XL has the same 105 deg. angle of view. This lens is considerably smaller and lighter. Despite the different focal length, do these lenses 'see' the same - or in other words are they roughly equivalent lenses as they have the same angle of view? The 90mm is crowded to the back of my Technika V and I run out of camera room using a lot of shift. The 110 would sit farther ahead and as the rear element is smaller, it seems that I might get more shift with it. I'd appreciate any responses to help me with this. Thanks.

Emmanuel BIGLER
3-Nov-2004, 13:03
William. Both lenses are able to record the same portion of image space i.e. 105 degrees but the 110 will
give you a slightly narrower field angle as recorded on the same piece of film.

You'd get exactly the same field angle on both lenses by using two similar film formats, except that for the 110 you'd have to scale film size by a linear factor 110/90.

In other words the total usable image circle is 110/90 times bigger for the 110.

Brian Vuillemenot
3-Nov-2004, 14:26
Both lenses have the same angle of coverage, that is 105 degrees. This gives the 110 SSXL a larger image circle than the shorter 90mm lens with the same angle of coverage. However, both lenses do not have the same angle of view (what you see on the ground glass). The 90 mm has a slightly wider angle of view- equivalent to about a 24 mm lens in 35 mm terms, whereas the 110 SSXL is approximately equivalent to a 28 mm lens in 35 mm. I hope this makes sense to you!

ronald moravec
3-Nov-2004, 14:58
Angle of view and angle of coverage are different. Angle of view is smaller with the 110, but the 105 deg coverage is the same.

The 90 with 105 coverage will cast a smaller image than the 110 because it is closer to the film.