View Full Version : 65mm or 75mm for 4x5?

Svante Johansson
17-Sep-2005, 13:11
I am quite new to large format photography, but my results are so encouraging that I decided to purchase a wide-angle lens for my Sinar F. In 135 I don’t go wider than 28mm, but I felt that with the 4x5 I could afford more cropping, and decided to go for a 75mm lens to be used mainly for landscape work.

I ordered a used top-class 75mm from a reputable dealer, and picked up a wide-angle bellows from another source. When the lens arrived it turned out that the dealer had made a mistake and I received a 65mm. I have been offered a credit for the lens, or the opportunity to exchange it for a 75mm of similar quality. The lens I got is in perfect condition, and I think both options for compensation are reasonable, but I can’t help wondering what to do. My questions to the more experienced wide-angle users on the forum are:

1. The image circle of the 65mm is 170mm while the 75mm has 195, meaning that the 65mm allows 10mm of rise while the 75mm allows 30mm. Is this a significant difference from a practical point of view? (With my 150mm Xenar I rarely use more than 2-3cm of rise.)

2. How many degrees of front tilt does the 65mm allow?

3. Is it possible to let the focus plane cover an object on the ground two meters away and tree-tops or mountains at infinity with the 65mm and front tilt? (Is it possible with the 75mm?)

4. I understand that back tilt does not “consume” the image circle in the same way as front tilt. Would it be possible to achieve the result asked for under 3. with back tilt?

5. I understand that light fall-off is more severe with the 65mm. Is the difference in this respect between the 65mm and 75mm so large that I could get away with not using a centre filter for the 75mm while the 65mm demanded one?

6. Are there any other factors that I should consider?

Ted Harris
17-Sep-2005, 13:21
The most important answer is that it is all a matter of taste and choice. For my purposes all the rise you can get is a good thing (same with shift). As fo ryour specifics, if iunderstand you correctly there should be no difference between what you can achieve in terms of near - far focus using rear tilt and either of the lenses.

My own thoughts .... at the moment 75mm is the widest lens I own and it seldom gets used in the studio (once in a very longwhile for some food stuff but thta is it). It gets a decent workout in the field though. Years ago I had a 65mm. I switched to 75mm because I DO appreciate the additional ease of movements and reduction of compression in the bellows when I am shooting with a standard bellows on a field camera (bothmy field cameras take a bag bellows but I find it a lot easier to use the 75 and NOT worry about changing bellows) this will only be a consideration if you ever get a field camera but worth thinking about.

Ken Cravillion
17-Sep-2005, 14:53
I shoot landscapes. In the past I had a 75mm. I did not have a center filter for it. Later I got rid of the 75mm in favor of a 65mm. I like this lens but find that you really should get a center filter for it. I found a used Schneider CF which was made for the lens (which is a f/5.6). I like going wide so I prefer the 65mm.

chris jordan
17-Sep-2005, 17:22
I have a 75mm and see little reason to go for a 65mm. I depends on what your intentions are. Another factor to consider...a faster lens of a given focal length will generally provide a larger image-circle, allowing both greater movements and easier viewing.

Leonard Evens
17-Sep-2005, 18:36
When you try to figure possible rise, remember that the figure is the diameter of the image circle, so you only have roughly half the difference between the diagonal of the frame and the diameter of the image circle available for rise. (It is actually more complicated than that, but that figure is a good rough approximation. You have to examine the geometry carefully and it works out differently for landscape and portrait mode.) 195 - 153 = 42 and half of that is 21, so that or perhaps a bit less is the maxium allowable rise.

Generally with wide angle lenses you may need less rise because so much is already included in the scene. Also, unless you have a bag bellows, it is hard to take advantage of a large image circle with a wide angle lens because bellows stiffness limits movements. The main reason for using rise or fall with a wide angle lens is to avoid a large empty foreground. If you use a near/far type of composition, this usually won't be a problem because you want to emphasize something in the foreground in any case. But I've found with architectural photography that I do need to use some rise both to include the entire structure in the frame and to avoid what is usually an uninteresting and empty foreground.

You tend to need less tilt with a wide angle lens to accomplish the same sort focus than you would with a longer lens, so I don't think you would have any trouble with what you describe. The way to think of it is that the smaller the hyperfocal distance, the less tilt you need for the same purpose. And of course, shorter focal length lenses have considerably shorter hyperfocal distances.

Another thing to keep in mind is that wide angle lenses produce "distortions" and the shorter the focal length, the more obvious these distortions become. For landscapes, the major such "distortion" is that objects appear smaller than you expect them to be.
How to deal with such things requires great skill in composition.

Myself I started out with a 90 mm lens as my shortest focal length, and I can't say I've entirely mastered it. I did eventually get a 75 mm lens, but I don't use it very much. If I were you, I would exchange the 65 for the 75 you ordered. The 65 would probably work quite well as a mediium format lens, but for you at present, it is not going to be much use.