80/110SS XL - light falloff

[Ed Richards]

I have seen a couple of places where folks maintain that these lenses have a greater light falloff than the traditional tilted pupil wide angle lenses. Looking at the curves for these lenses, and the fact that they share center filters with conventional wide angles, I do not see any evidence that the light fall off is any different. Can someone enlighten me on this? (Having been introduced to the bad back world this summer, I am looking at lighter gear.)

[Mark Stahlke]

Hi Ed,

I'm mostly shooting 4x5 landscapes on color transparency film (E100VS and Velvia). Here are my thoughts on the 80SSXL and 110SSXL lenses. My opinions are based on looking at actual photographs not curves published by the manufacturers.

Some time ago I replaced my Caltar II-N 75/4.5 with an 80SSXL for the weight savings. This proved to be a mistake. In my opinion, the light fall off characteristics of the 80SSXL are objectionable without a center filter. I never felt the need for a CF with my 75mm Caltar. I bought a Schneider IIIb center filter for the 80SSXL. The CF's 86mm accessory thread meant that I had to switch from a plastic Cokin P filter holder to a metal Lee holder and larger filters. That, combined with the CF, ate up the weight savings. I've gone back to using the 75mm with the Cokin P filter holder and the CF stays at home.

Later I purchased a 110SSXL which I use for the same subject matter. Thankfully, I don't see any need for a CF with this lens.

Some folks will say the fall off is easy to correct in Photoshop. I have a couple of issues with that. First, my Photoshop skill level is such that the less work I have to do in Photoshop, the better off I am. Second, if I've used movements like rise or fall the center of the fall off is no longer the physical center of the photo. I find it very difficult to accurately locate the optical center when making corrections.

I've attached the photo that convinced me to buy a CF for the 80SSXL. I think this would be a lovely photo if the exposure was even but I find the fall off both obvious and objectionable. For this post I went back to the original scan and made no effort to correct the fall off in Photoshop.

[Henry Ambrose]

I'll second pretty much everything Mark wrote. The 110 is not a problem without a CF and its everything good that's ever been written about it. The 80 will need a CF. I thought it was OK for B&W but even then not 100%.

There is no correcting fall off as in Mark's example. Maybe good enough to show on the web but you'll not fix it good enough to make a big fine color print. Color rendition changes with exposure so if you've got large areas of uniform color you're not going to correct it by a bit of dodging or some kind of mask.

I sold off my expensive stuff when I stopped shooting sheet film for work. I don't miss the 110 so much but I do miss the 80. I have a 90 and 135 which is not a bad pair but I do like the angle of view of the 80 over the 90.

[Andrew O'Neill]

I occassionally borrow a friend's 110XL on my 8x10 and I have never seen any fall off.

[Brian Ellis]

I owned the 80 and used it extensively. I never noticed any unusual fall-off and never needed a center filter. I used it exclusively with b&w film.

[Bruce Watson]

I have seen a couple of places where folks maintain that these lenses have a greater light falloff than the traditional tilted pupil wide angle lenses. Looking at the curves for these lenses, and the fact that they share center filters with conventional wide angles, I do not see any evidence that the light fall off is any different. Can someone enlighten me on this? (Having been introduced to the bad back world this summer, I am looking at lighter gear.)

I have them both and use them both for 5x4. To be honest, I've never seen enough light fall off in the corners to think it's worth trying to correct, let alone worth the cost and bother of a center filter. The biggest print I've ever made came from the 80mm lens. I didn't use a center filter, made no effort to correct for any light fall off during the printing process, and there's no noticeable light fall off in the final print.

These are sweet lenses IMHO. Very. Spend some time with the 80mm and see if you think you really need the center filter before you go after one.

[mrossano]

I'm not sure which illumination curves you're looking at. Schneider's data sheets show unambiguously that when the relative illumination is compared at f/22, infinity, equal angles off-axis, the 8 element Super Angulon types follow 1/cos^3 almost exactly and the Super Symmar XL series follows 1/cos^4 almost exactly. The fact that several lenses from each series share a common center filter recommendation is irrelevant. None of the recommended center filters corrects fall-off completely, nor are they designed to. Schneider states that clearly.

Whether or not you feel compelled to use the center filter is another matter. Depending on your taste or artistic vision, you may actually prefer the uncorrected effect. That doesn't alter the basic physics involved. This whole discussion highlights that photographys is both art and craft. How much of each it is to you is an individual matter.

[Drew Wiley]

Negative falloff is sometimes inadvertently corrected by analgous falloff in the enlarger
lens or lens/diffuser combo. The only way to figure this out is to make precise negatives of a blank neutral gray and read the resultant negative with a densitometer.
I always use plus development to exaggerate any difference. So far, I've personally
found Schneider's CF recommendations to be right on the money. Sometimes I like
the look with the CF, sometimes not - but that's an esthetic decision.