Resolution difference between Schneider 72mm XL f/5.6 and Schneider 75mm Super Angulon f/5.6

[Edie]

Is there any resolution difference between the new Schneider 72mm f/5.6 XL lens and the Schneider Super Angulon 75mm f/5.6 lens? The 72mm is heavier, but if the resolution is better, I'm tempted to go with this lens. I'm shooting 4x5. I'm a lso interested in anyone's experience with the 72mm or 75mm.

[Bob Salomon]

Ask for the MTF, Color and distortion curves and compare them. You should also compare them to the Rodenstock Grandagon-N 4.5 and the Nikon to see what is what.

[Michael S. Briggs]

The MTF curves etc. for the Schneider lenses are available on the web starting from http://www.schneideroptics.com/large/super_angulon/super.htm (Rodenstock supplies similiar data in printed literature; I've never seen such from Nikon).

The big difference between the two Schneider lenses is their coverage. The 72 mm f5.6 Super Angulon XL has an amazing 115 degrees, 226 mm diameter circle of coverage, while the 75 mm f5.6 Super Angulon has a respectable 105 degrees, 198 mm diameter circle of coverage. The XL will allow greater movements at the cost of higher price and greater weight (557 vs 380 grams). A quick look at the MTF curves shows them to look pretty similiar as a function of maximum image height, but note that the maximum image heights are different.

As an example of what the difference in coverage means, with the back in landscape orientation and focused at infinity, one should be able to use a front rise of 48 mm with the XL and 31 mm with the non-XL. Whether the difference in coverage is worth the price and weight cost depends on each photographer's preferences.

[Jim Blecha]

Hi Edie,

I own the Schneider 75mm SA f5.6 and it performs just fine for 4X5. Movements are ample for most architectural applications. I doubt there's any significant resolution difference.

Your real questions should be: cost, size, weight, filter diameter (you will want a center filter with either for outdoor photography) and is the additional distortion (due to increased movements you probably won't need) worth it?

$ vs $ needs no explanation. I know of one photographer who returned a 72mm XL because the rear element wouldn't fit through the lensboard mount of his field camera. Do you really need the extra weight?

If you plan to use filters, be aware that screw-in filters (except specially designed center filters) will vignette your image when extreme movements are used and Lee doesn't make a wide-angle adapter in 95mm. The standard Lee adapter will vignette when using extreme monements.

As your movements increase, so does your distortion. It's just plain physics. This is a clear-cut case of less is more.

I also find that the Schneider center filter 3B for the 90mm f8 (1.5 stop difference from center to edge) works well for both the 75mm f5.6 and 65mm f5.6. All have 67mm filter threads.

[Edie]

Thanks everyone. Very helpful information. I thought I would post the reply I received from Michael Klayman of Schneider Optics. He writes, "The resolution differences between the lenses are fairly small, but if you want me to pick a winner, I would say the 75 is slightly sharper. Keep in mind that the resolution charts measure resolution across the entire image circle, so since the 72XL covers more, the resolution might be the same for the same size image circle as the 75, but softer at the very edges of the 72XL. I would still recommend the 72XL if you plan on making a lot of lens movements. If you know how to read MTF charts, you can take a look for yourself at our website."

I agree with Jim that less is more, at least in this case. Weight, filter size and resolution seem to favor the 75mm SA f/5.6.

[Larry Huppert]

I use a 75mm SA, and find it a very nice lens. I shoot mostly architecture, and found a situation last week where an 72XL would have come in very handy. The only shot possible of this commercial structure without including some unattractive trees could be done with the 75mm from a focal length standpoint, but I ran out of coverage. I got the top of the building in, but the corners of the transparency were vignetting. The client will scan the image anyway, so the dark corners can easily be removed in Photoshop (it was nice blue sky). I ordered a 72XL with Copal Press a while ago, and look forward to using it. The whole filter thing with the 72mm is a problem however. A prior post stated that Lee didn't make anything for the 72mm XL. This isn't true. They make a dedicated foundation kit specifically for this lens and the 90XL (I believe?). Steve Grimes can also make a similar item, so you can still use 4" filters. Making something which will work the the center filter on the 72XL is another matter.