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View Full Version : what's a normal lens?



james norman
30-May-1999, 20:04
thanks to all who answered my previous questions. it appears that a 165mm lens is, technically, the "normal" focal length for a 4x5. however, no manufacturer seems to make a 165mm for a 4x5. that focal length is available for 8x10 format , but at a high price. where can i get a reasonably priced 165mm lens for 4x5?

Ellis Vener
30-May-1999, 21:16
Stop worrying about an absolute abstract number derived from a mathmatical formula and get a 150mm or if that is too wide get a 180mm and start making photos.

Bob Salomon
30-May-1999, 21:47
A normal lens is the diagonal of the negative. Not all 45 cameras have the same film dimensions so the standard normal is the 150mm.

However lenses as short as 120mm are also considered normal as are lenses as long as 210mm. It simply depends on what you want as "norm

Bob Salomon
30-May-1999, 21:47
A normal lens is the diagonal of the negative. Not all 45 cameras have the same film dimensions so the standard normal is the 150mm.

However lenses as short as 120mm are also considered normal as are lenses as long as 210mm. It simply depends on what you want as "normal"

james mickelson
31-May-1999, 00:23
Uh. Excuse me perfesser. The film diagonal is not the same on all 4x5 cameras? The diagonal of a standard sheet film holder doesn't vary on any of mine. And I have eight different kinds of holders. And a 150 lens is normal for 4x5. A 135 is wide normal and a 180 or 210 is long normal. And that guys really anal for wondering the question anyway. Is it zone 0 or zone 1? Sheesh!

Bob Salomon
31-May-1999, 05:51
While the diagonal of the film holders are the same the cameras can still make a difference. For instance a Linhof Kardan GT/GTL or Technikardan has a slightly different negative area than a Technika due to the way the back is made.

David Grandy
31-May-1999, 09:16
The reason the 165 is so expensive is because it really is a wide angle for 8X10. The "normal" focal length for 4X5 is 162.64mm - sort of. This is the calculated diagonal of the negative, which is based on the outside 4X5 dimension of the whole NEGATIVE not the smaller usable area of the negative.

The problem (and this is a very small problem) is that there are two definitions of normal. The first is the diagonal of the negative, which every one is computing; and the other is "what your eye sees". In 35mm photography the film diagonal is 43mm, but all the manufacturers consider 50mm to be closer to what you see. In medium format photography the normal lens sold is often much closer to the diagonal measurement and has a slightly wide look to it.

So you can choose a 150 or a 180 to straddle "normal", and although it might not be mathmatical perfection, does it really matter?

james norman
31-May-1999, 12:33
again, thanks for all your information. i inquire about this focal length for a specific reason. i occasionally have to "re-photograph" historic "main street" images. the ones from the late 1800s appear to have been made with an 8x10 and likely a "normal" 300mm lens, while others were made as late as the 1930s with a 5x7 graflex, with maybe a 210mm (those focal lengths are assumptions - if old studio cameras actually had 350mm's or if 5x7 graflex's normally had 240mm's or something else, please let me know.) i have been using a 135mm to do these re-photographs, but it is too wide. my 210mm is way too long for this - i cannot get the position, and there is too much image compression. i hesitate to buy a 150 since it so close to my 135, but i am afraid a 180 will still be a bit too long for this use. i felt like a 165 might be a good compromise. can i assume, then, that there is no such lens for a 4x5?

N Dhananjay
31-May-1999, 13:41
hi if re-photographing certain scenes is your problem, lens focal length might not be too much of an issue. perspective (assuming that is what you are worried about) is a function of camera position and not focal length. so i would go ahead and use the slightly wider focal length and try to find the exact spot which was used to take the older picture (!) and if needed, crop the image in printing. hope this helps. dj

Ellis Vener
31-May-1999, 15:40
Your biggest problem is going to be matching perspective, not focal length. Figure out a way to do that and then pick a lens to match the angle of view.

Marv Thompson
31-May-1999, 17:40
The 165mm you are looking at is probably a Super Angulon f8, I have a 165 f6.8 Angulon. It is in a Compur shutter, stops to f45, speeds of 1 sec to 1/100. It came on an old beat up 8X10 that I picked up for $250.00. The lens is old and funky, works and on 8X10 except that is soft around the edges. It would have plenty of coverage for movements in 4X5, and the edge softness wouldn't be a factor. Obviously the lens you want is out there, it will just take a little digging to find one.

Ron Shaw
1-Jun-1999, 11:37
This focal length used to be more common than it is now. I have a 162mm Graphlex Optar (made by Wollensak), which covers 4x5 well, but this focal length seems to have dissappeared in favor of the 150 as a mormal. If you really need 162, you can still find these on the used market (along with the identical Wollensak version, the Raptar). Mine is uncoated. I dont know if others are coated or not.

Kevin Kemner
13-Jun-1999, 14:23
Goerz made an older Dagor that was 6 1/2" which puts it around 165mm. The one I have is in a dial set Compur but works very well. I paid about $290 as the glass is very clean. It works well for both b&w and color.