Best 21mm lens for infrared photography

[notontv]

I absolutely love the images I get when doing IR with the 35mm Summaron 3.5, but would love to go wider. I have some lenses that have the 'hot spot' with IR, others that don't but just don't create the same richness of quality. I am using M-mount or LTM lenses, but really am just interested in the science behind this. I assume that the biggest factor is using an older lens without coating, but that doesn't seem to be the whole story. Who knows how this works?

 

[raid]

The CV 21mm may be the easiest way to get a 21mm that is not too costly.

Another option may be to use an SLR 21mm lens.
http://www.rangefinderforum.com/forums/showthread.php?p=2015226#post2015226

 

[notontv]

I have the 21 Elmarit, but it is much 'flatter' of an image with infrared. As are the 35 & 50 Summicrons. There is something about the older Summaron that is magic with IR

 

[JMQ]

I would think any lens that would take a deep red filter (R-72) would be sufficient. After that I would choose a lens that reflects your personal taste.

My preference would be the 21/3.4 Super Angulon but 48mm filters are none too common.

Perhaps the CV 21/4 or even one of the Leica Elmarits. . . .

You can easily buy a 48mm to 52 or 55mm step up adapter. That's what I use on my SA with the R72.

 

[Ronald M]

My 21 2.8 pre asph seems to work ok. I use the 092 B+W

 

[charjohncarter]

You may get some gradation in your skies with a very wide lens (20mm). When I shoot into the sun with IR the sky is much lighter than with the sun to my back.

Slightly into the sun:

Sun to my back, same day same exposure:

The 20mm wouldn't be a IR killer, but maybe something to think about.