Ben Horne
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I picked up a 45mm TS-E lens here on FM for use on a trip. I LOVE this lens. Now that I am use to the lens movements, I find it difficult to use "regular" lenses now. I have learned several things about this lens that I thought I should pass on. First of all, you really NEED the angle finder C in order to tell if you have the lens properly setup. Otherwise, it is difficult to tell in the viewfinder if you have the lens tilted and focused properly. Here is a test shot yesterday with the 45mm TS-E tripod mounted, tilted almost to the max. I believe the shot was taken at f/8. With a normal lens, you'd get only a small percentage of the shot in focus at f/8.
Sorry for the huge file size. This image does not compress well.
http://www.benhorne.com/photos/45a.jpg
Here is another example of nearly full tilt. The cliff face in the foreground is only a few inches from the camera. This sort of sharpness and focus would be impossible with a normal lens, even stopped down all the way.
http://www.benhorne.com/photos/45b.jpg
Of course, if you use the lens the opposite of how it is meant to be used, you can have a super shallow DOF as a result of the tilted plane of focus.
http://www.benhorne.com/photos/45c.jpg
It is best to meter the scene before tilting the lens. Otherwise, it will be off by about a stop. Shifting does not seem to have quite the same issue.
I find it easiest to focus on the foreground, then tilt for the background focus. If you use an angle finder, it is much easier to fine tune the setttings, especially if you will be shooting anywhere near wide open.
I was well aware that Chromatic Aberration would be an issue with this lens. It's quite a bit more than I thought, but it also isn't that difficult to get rid of. You can NOT use the CA fix in Adobe Camera Raw since this is a different style of CA. On a normal lens, you will find that the red channel is slightly larger yet centered. As a result, the further you get from the center of the lens, the stronger the CA will be. Photoshop can essentially shrink the red channel, yet keep the center aligned, and you will have proper alignment.
With a TS-E lens, your image circle is huge, and depending on how you have the lens tilted/shifted, you will see only a portion of the edge of the image circle. This means that the CA is not radial, and centered in the middle of the photo. With a little bit of experimentation, I found that if you shrink the red channel to 99.92% of it's original size (on the 1DsmkII), you will now have a red channel that is the same size as the blue and green channels. Then you just have to align it. In the shot with the rocks on the beach, I set the height to 99.92%, left the width at 100% (uncheck the constrain proportions box) since there were not any red channel alignment issues on the other axis. Here is a 100% crop before and after the red channel shrinkage.
http://www.benhorne.com/photos/45d.jpg
http://www.benhorne.com/photos/45e.jpg
The magic number will vary based on which lens, which camera, and how far you have the lens tilted. It's not too difficult to experiment to find the proper number.
I also found that 99.92% worked for correct CA on this lens that results from shifting to the max.
My main purpose for buying this lens was allowing compositional changes when shooting level with a panorama setup. However, the usefulness extends well beyond that. I'm really looking forward to shooting wildflowers in the desert this spring. After owning this lens, I really would like to get the 90mm TS-E.
Edited on Feb 25, 2008 at 01:57 PM
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