Which lens most like 24mm in 35mm format?

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Having used my 24mm lens extensively when I owned a 35mm camera, I'm looking for it's closest companion in 4x5. I'm confused because sometimes charts say 90mm, others say 75mm. If anyone has experience with both of these lenses and can comment on this, I'd appreciate hearing from you as I am at the crux of buying my first WA lens. Matthew

-- Matthew Cordery (cordery1@llnl.gov), January 27, 1999


The 75mm or 72mm is closer to being equivalent to a 24mm lens on a 35mm format camera. In my experience

-- Ellis (evphoto@insync.net), January 27, 1999.

I have rented both the 75 and 90mm for my 4X5 to help me make this same decision. The equivalent to a 24mm lens on a 35mm camera would probably fall somewhere between 75 and 90mm. One thing that I have noticed, however, is that when using significant tilts or swings, the angle of view captured on film will decrease slightly. Because of this, the 75mm might be closer to the angle of view that you want. The 75mm is heavier and costs more than a 90mm f/8, but for me it is the right choice. I also plan to get a medium wide angle lens at some point, probably a 110mm, so the 75mm will compliment this better than a 90mm lens would.

-- Lester Moore (Les4moore@aol.com), January 27, 1999.

The confusion comes from the fact that the aspect ratio of 35mm and 4x5 are different. If you crop the 4x5 to make it match the 35mm, then the 75mm is closest. On the other hand if you crop the 35mm to make it match the 4x5, then it's the 90mm. One rule that i've found to work for me in selecting focal lenghts for LF is in doubt go for the wider since you can always crop with little effect on print quality.

-- Quang-Tuan Luong (luong@ai.sri.com), January 27, 1999.

Matt- According to the formula I use, a 90mm lens on 4X5 is a little longer (27mm) than a 24mm on 35mm; and a 75 is a bit wider (22.5mm). If you're interested, I base this calculation on the relative size of the film in the horizontal dimension. Others may have other ideas (probably all good), but this seems the most useful to me, especially when talking about wide lenses. After all, what you really want to know is, how wide will the view be. With 4X5 and 35 its easy to calculate since 120mm (the real long dimension of 4X5 film), divided by 36 (the long dimension of 35mm film) is 3.33333333333. This can also be written as 10/3. So, if you have a 35mm lens and you want to know the equivalent in 4X5, simply multiply by 10, then divide by 3. 24x10=240/3=80. Or the other way around, multiply by 3 and divide by 10. 75x3=225/10=22.5.

-- Steve Pfaff (spfaff@hrl.com), January 27, 1999.

I have to disagree somewhat with the answers above. I think the 90mm is more equivalent to the 24mm than the 75mm is. There always seemed to me to be more to lens equivalency and aspect ratio than the simple mathematics of the question suggests. For example, I recently took a photo that I was quite pleased with using an 80mm "normal" lens on a 6x6 medium format camera. I later tried to take an equivalent photo on 35mm film and found that I needed a 24mm lens to include all the important elements of the picture. And in the end, the 35mm composition was not as nice as the original. My point is, that for me anyway, a 90mm on 4x5 has always had the feel of at least a 24mm lens on a 35mm camera. I rarely feel that I need anything wider than 90mm. I would look real hard at getting the 90mm. As previously pointed out, it will probably be cheaper and lighter. Also, there is less concern about needing a center filter. However, if you do a lot of architectural photography, get the 75mm. In this case, it always seems that wider is better.

-- Tom Hieb (thieb@cybertrails.com), January 27, 1999.

I have used 72mm, 90mm and 110mm and longer lenses. The 72 mm feels very wide, whereas the other just are wide. I rarely use the 72 mm. The 72 mm (Schneider super angulon XL f5.6) is MUCH harder to use than the 90 mm (Nikkor SW f8) that I have used, despite the 72 mm being faster. I think this is because of the fall off of the light towards the corners, and the extereme angle to the ground glass that the light rays make. The 72 mm is also quite heavy. You might want a center filter for the 72mm, which adds considerably to the cost.

If you want a lens that feels wide, the 72 mm is probably for you. I think that the 110 mm Schenider Symmar XL is a great lens and the best choice (if you can afford it) for a medium wide. It makes little sense to own both a 90 mm and a 110 mm. You might want to consider you ultimate set of lenses in making the decision. I use the 110 mm lens far more frequently that the 72 mm. Most importantly, the 110 mm focal length that seems appropriate for most of my "wide" photographs, but it is also much lighter and easier to use.

Mathematical comparisons between 4x5 and 35 mm are problematic because of the differing aspect ratios. Some tables use the film diagonal, others the long dimension. If most of your photographs are in landscape orientation of landscapes, then the long dimension of the film might be the best criterion. But the formats can feel different because of the aspect ratio and the typical subject one uses each for.

-- Michael Briggs (ms.briggs@cwix.com), January 27, 1999.

One more issue that no one has really mentioned in comparing aspect ratios for different formats is the effect of back tilts. You can exaggerate perspective by tilting the back with a view camera. Thus, you can, for instance, with a 90 mm lens, tilt the back to increase the foreground/background perspective. If what you like about the 24 mm is its wide angle of view, then focus on the angle of view in selecting a 75 mm or 90 mm. However, if what you like about the 24 mm is its exaggerated perspective, you can get MORE exaggerated perspective from a 90 mm with back tilt.

-- Howard Slavitt (has@cpdb.com), January 27, 1999.

If you are just looking for a comparison one method is to do a quick check using the "normal" lens choice in each. For 35mm it is a 50mm lens & for 4x5 it is a 150.(yes, I know this isn't technically correct, just a rule of thumb that gets us close). So, multiply lens choices by 3 for a quick check. 3 times 24 is 72. That gets you in the ballpark for an initial choice. Factor in the difficulty of working with wide angles with the camera of your choice and the different aspects of the negatives and you find that personal preference plays more of a part in this than just technical equivalents. A 72 to a 90 will probably work fine depending on your preferences in looking at the chromes on the light table from both formats.

-- Dan Smith (shooter@brigham.net), January 28, 1999.

One thing is that is really different from 35mm to 4x5 is the additional height of a 4x5 image (a 1:1.125 ratio) compared to a 35mm image (1:1.5). If you go strictly by long dimension coverage (which is the way I do it) than a 75mm is more equal to a 24mm. But you are going to get a lot more vertical coverage. And yes you can use back tilt to increase the angle covered, but you can't do that every time. In general I think a 90mm lens is more useful than a 75mm lens as a first WA lens. Can you rent either or both for week and see which you like?

-- Ellis (evphoto@insync.net), January 28, 1999.

Thanks to everyone for these great replies! Lot's of food for thought. While I sometimes used a 24mm for wide landscape shots, what I found is that I really liked using it with the long axis of the frame oriented vertically, so that I got a lot of foreground to background perspective. I often carried around a 28mm lens with me, but would more often than not leave it behind rather than carry the extra weight. I guess I *will* have to break down and rent a lens for a day!

-- Matthew Cordery (cordery1@llnl.gov), January 28, 1999.

Hi Matthew, Which camera are you using?

-- Ellis (evphoto@insync.net), January 28, 1999.

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