On Mon, 15 Jul 2013 20:19:14 -0400, rwalker
wrote:
On Mon, 15 Jul 2013 18:42:50 -0400, Fred McKenzie
wrote:
In article ,
PeterN wrote:
On 7/14/2013 3:56 AM, rwalker wrote:
As I mentioned elsewhere, I got a Canon 5DIII about two weeks ago. I
decided to see what kind of infrared sensitivity it had, so I got an
R72 filter and took a few shots. This was one of the better results.
10 seconds, F4, ISO 100.
http://www.flickr.com/photos/5164668...1330/lightbox/
Something is missing. Infrared is supposed to have quite a different
look. You must have done something in post.
http://peternewman.smugmug.com/Photo...mw4B9R#!i=1730
614889&k=WGpJLmN&lb=1&s=A
PeterN-
I took one roll of infrared film about 50 years ago, which definitely
made vegetation white. It looked like a snowstorm in July! I also have
played with an IR filter on a couple of DSLRs with mixed results.
Comparing your photo with RWalker's, it occurs to me that the reason his
exposure is so long, is that the camera sensor is not sensitive to IR.
The exposure could be dominated by visible light attenuated by the
filter, with relatively little IR response.
Seeing his later exposure using the Hoya filter seems to reinforce my
theory. It will be interesting to see the effect he achieves using the
Hoya filter to photograph outdoor vegetation.
If there is a conversion that increases IR sensitivity, wouldn't it
degrade the camera for normal use?
Fred
I'll have some photos of outdoor vegetation in a bit. Vegetation
certainly shows up very light colored. From my reading, I know that
an unmodified DSLR has an infrared filter in place, but it doesn't
block all the IR, but most of it. So with an IR filter and long
exposures, you still get some infrared.
Ok. Some successful experiments outdoors this afternoon using the 50
mm. lens and the Hoya R72 filter on the 5DIII.
A field of corn (maize):
http://www.flickr.com/photos/51646689@N00/9297836418/
A general view of the same vicinity. Not sure why such vignetting.
This is a 30 sec. exposure at 100 ISo and F1.8. At 10 seconds I still
get the vignetting but not as severe. But the vegetation certainly is
what I was expecting:
http://www.flickr.com/photos/5164668...ream/lightbox/
A crop of the above:
http://www.flickr.com/photos/5164668...ream/lightbox/
I'm much more satisfied now.