Which lens? (was Re: test post only)

[boblong@xxxxxxxxxxx (Robert Long)]

On Sun, 24 Nov 1996 06:44:20 +0000 (GMT), you wrote:

|At 04:40 AM 24/11/96 +0000, Ron Walton wrote:
|[snip]
|>
|>     What lenses do you use for best infrared results.  I believe =
someone
|>suggested using fixed focal length lenses for best results.  I don't
|>remember thier reasoning tho.
|
|I normally use 35mm because the only dark red filter I have for my leica=
 is
|meant for its 35mm lens (its a series VII and fits in the hood).  I also
|like the perspective for IR work.  I believe that lenses with many =
elements
|are prone to lens flare because the coatings designed to reduce flare =
are
|not of the optimal thickness for infrared wavelengths.  I DO notice much
|more flare with my IR shots than similar shots with conventional film.  =
If
|all of this is true, then 15+ element zoom lenses are going to be
|particularly susceptable.  Correct me if I'm wrong!

Whether a wide-angle is best for IR work obviously depends on the
subject matter and the intended treatment.  But yes, I find I use a
28mm most of the time.  It add subtly to the surreal quality of the
pictures.  I wish I could justify the expense of a 16mm fisheye to go
whole-hog in that direction--as Willem did with one of his snow
pictures, I believe.

One would think that multielement zoom lenses would make color
correction outside of the design band even more problematic than
simpler designs do, but I'm not a lens designer.  As far as flare
goes, if you're using HIE, the flare is very hard to see for the
"highlight bloom" due to the lack of an antihalation backing.  When
the highlights "bleed" beyond the frame boundaries, you know it's not
flare!

Bob Long
(boblong@xxxxxxxxxxx)

------------------------------

Topic No. 6