I'm not sure I understand your question. There should not be any correlation between the color of reflection and temperature (emission from a heated black body would be different story, where temperature and color are well correlated, the hotter the shorter the wavelength). "That something else" in my previous post referred to anything that happens to appear brighter than the dark green vegetation without the filter, but does not get "brightened up" (relatively speaking) when seen through the IR filter. Chances are that it is reflecting more light and has a lower temperature (hence cooler in temperature, not necessarily in color).
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Is the human eye capable of seing infrared?
- Thread starter Daniella68313
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Daniella68313
Forum Pro
But since my eye cannot detect a change in temperature, only a change in value (lightness/darkness) or in color, how can the so tiny difference in temperature, if any, influence what I see. Another confirmation of this is that I can see this effect also in the shadow, where the vegetation is quite cold. It is not very warm here today..and the vegetation is pretty chilled.
--
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
Jeremy Rosenberger
Leading Member
When looking through the IR filter, the foliage appears brighter not because it is brighter (the IR filter certainly isn't intensifying the light coming into it), but because its surroundings appear so much darker. So naturally the foliage will appear brighter by comparison.
Cheers,
Jeremy
--
Jeremy L. Rosenberger
http://www.frii.com/~jeremy/
Cheers,
Jeremy
--
Jeremy L. Rosenberger
http://www.frii.com/~jeremy/
Parker North
Forum Enthusiast
I think I saw a post by Melanie recently, she says she has viewed an image from the 10D, it was fine she said, the center spot was similar to the 7 she has I think, if I am not mistaken.
You know a good 3mp ir camera?? I may be able to get buy with that for printing. I really need that printer and flashes before the 10D, a small camera I might slip in between. I could really use that at the 3000 acre state park that is 8 minutes away from here!! If I can color it like you, I really like the colored ir the most, they do more for me than most straight ir.
--ExactlyHmm I am sorry but I do not understand your question. what to aMaybe I can find a used one of these to play with. I want to get 2
flashes and one of those 2200 printers or something like that
first. Work before play.Or do you know what to a bank first.
Can't do that.
bank first? do you mean get a loan?
first, if I had unlimited cash, I would just buy everything,
inclding a 10D. Then I would not have to worry about it.
Can I make 8x10 or 7 1/2 x 22 prints with these models, at real
nice quality level?? If I cannot make at least nice 8x10 I can't
use it. I may need to crop large percentages with smalll lens if I
try on my fish. Probably no chance then. I have not looked at these
two yet, I am taking a look now.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND,
Hoya-red-Intensifier, Hoya R72.
Parker North
Forum Enthusiast
Cheers.
Daniella68313
Forum Pro
there is no good 3mp for IR. they started to have the hot mirror from 3mp and up. A good ir camera is one that let you take handheld shots or fast enough shots so that you can stop the blur from the wind in the vegetation. So far the 2mp cameras are good, but after that the 3mp are not good. amoung the higher mp camera the Sony 717, 707, Dimage 7 are good.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
--I think I saw a post by Melanie recently, she says she has viewed
an image from the 10D, it was fine she said, the center spot was
similar to the 7 she has I think, if I am not mistaken.
You know a good 3mp ir camera?? I may be able to get buy with that
for printing. I really need that printer and flashes before the
10D, a small camera I might slip in between. I could really use
that at the 3000 acre state park that is 8 minutes away from here!!
If I can color it like you, I really like the colored ir the most,
they do more for me than most straight ir.
--ExactlyHmm I am sorry but I do not understand your question. what to aMaybe I can find a used one of these to play with. I want to get 2
flashes and one of those 2200 printers or something like that
first. Work before play.
Can't do that.
bank first? do you mean get a loan?
first, if I had unlimited cash, I would just buy everything,
inclding a 10D. Then I would not have to worry about it.
Can I make 8x10 or 7 1/2 x 22 prints with these models, at real
nice quality level?? If I cannot make at least nice 8x10 I can't
use it. I may need to crop large percentages with smalll lens if I
try on my fish. Probably no chance then. I have not looked at these
two yet, I am taking a look now.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND,
Hoya-red-Intensifier, Hoya R72.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
Higher temperature gives off more infrared and long red spectrum. What human eye is sensitive to is not absolute luminosity but relative luminosity. When all the strong light in the 600nm is cut by 99% by the IR filter, it is the tiny variation in the remaining red spectrum that decides what is brighter. It's a bit like the economic cycle, during the expansion phase, all the pig companies can fly, but when the inevitable contraction comes full force, the companies with the last few dollars end up owning the whole industry after all the fat is cut out. The ranking of bottom dollar reserve may not correlate with the ranking of total revenue at party time.
Live vegetation may actually stand out more in the far red spectrum in the chill because of metabolism.
Parker North
Forum Enthusiast
I almost bought a 717 when I got my 7hi. It did not have enough control for me and lots of other disadvantages for shooting fish.
I have looked at a lot of ir from those models, I think they do real good, but I am no ir expert, you know.
I think maybe I should think about a used 707, it has a "zeiss" 2.0 correct??
How fast is those sony lenses at full tele?? I think if my fish look good in ir, I can do lots of underwater plants too. The water temp is between 75-88 degrees. Otherwise how much did you say aused or refurb 7 goes for??
The 5mp will allow me to do some crops. The 3.5 on the 7hi is almost to slow for me now.
--I think I saw a post by Melanie recently, she says she has viewed
an image from the 10D, it was fine she said, the center spot was
similar to the 7 she has I think, if I am not mistaken.
You know a good 3mp ir camera?? I may be able to get buy with that
for printing. I really need that printer and flashes before the
10D, a small camera I might slip in between. I could really use
that at the 3000 acre state park that is 8 minutes away from here!!
If I can color it like you, I really like the colored ir the most,
they do more for me than most straight ir.
--ExactlyHmm I am sorry but I do not understand your question. what to aMaybe I can find a used one of these to play with. I want to get 2
flashes and one of those 2200 printers or something like that
first. Work before play.
Can't do that.
bank first? do you mean get a loan?
first, if I had unlimited cash, I would just buy everything,
inclding a 10D. Then I would not have to worry about it.
Can I make 8x10 or 7 1/2 x 22 prints with these models, at real
nice quality level?? If I cannot make at least nice 8x10 I can't
use it. I may need to crop large percentages with smalll lens if I
try on my fish. Probably no chance then. I have not looked at these
two yet, I am taking a look now.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND,
Hoya-red-Intensifier, Hoya R72.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND,
Hoya-red-Intensifier, Hoya R72.
Daniella68313
Forum Pro
why is the surroundings appear so much darker?
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
--
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
Daniella68313
Forum Pro
This is about how it looked when I saw it with my eyes and the filter. For exemple, the center tree bottom branch appeared brighter than the other branches, and it was also brighter when I took the photo. The little trees also had some variations in value and that was the same after taking the photo. The cloth that you see on the left were white and the vegetation that it was resting on was much darker..the difference when viewed with the eye and the filter is much less, same when taking the photo.
I don't know if it is the surrounding that is much darker, or the vegetation that gets much lighter, but the effect and the ratio light/dark for the vegetation is there. the vegetation seems to go from very dark to a light reddish tint.
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
I don't know if it is the surrounding that is much darker, or the vegetation that gets much lighter, but the effect and the ratio light/dark for the vegetation is there. the vegetation seems to go from very dark to a light reddish tint.
--
Daniella
http://www.photosig.com/viewuser.php?id=26918
http://www.pbase.com/zylen
C7OO FORUM: http://www.c700uz.com
c7OOuz, Dimage-7, Tcon14tele, C210tele, Cokin-173, Grad-ND, Hoya-red-Intensifier, Hoya R72.
William West
Senior Member
keith caldwell
Leading Member
Daniella you are clearly a girl with an insatiable curiosity so I would like to give you another project.
The next time that you are woken SUDDENLY from a dreaming sleep DON't open or move your eyes. Just concentrate on what you can see & attempt to make sense of any images.
This may seem a cranky request but I noticed sometime ago that I could see what appeared to be multi-layered parts of images stacked on top of one another in shades of black ,grey & white. If you continue to concentrate on these images you seem to go through them as if you are continually re-focussing through a series of images etched on celluloid.
I have never seen this phenomenon described & I am hoping that you or others can confirm my experiences. The most important thing to remember is that you must not open your eyes even in total darkness & try not to move - just concentrate on what you can see.
This is not as easy to do as it may seem at first because you have to be aware immediately when you awake of what you must concentrate on.
--
keith c
The next time that you are woken SUDDENLY from a dreaming sleep DON't open or move your eyes. Just concentrate on what you can see & attempt to make sense of any images.
This may seem a cranky request but I noticed sometime ago that I could see what appeared to be multi-layered parts of images stacked on top of one another in shades of black ,grey & white. If you continue to concentrate on these images you seem to go through them as if you are continually re-focussing through a series of images etched on celluloid.
I have never seen this phenomenon described & I am hoping that you or others can confirm my experiences. The most important thing to remember is that you must not open your eyes even in total darkness & try not to move - just concentrate on what you can see.
This is not as easy to do as it may seem at first because you have to be aware immediately when you awake of what you must concentrate on.
--
keith c
Petteri Sulonen
Forum Pro
Daniella wrote:
[snip]
Infra-red is defined as wavelengths longer than red no longer perceptible to the human eye, so by definition, we can't. There's nothing intrinsically different about infra-red: it's just electromagnetic radiation, just light light. The line between red and infra-red is somewhat arbitrary; I also wouldn't be surprised if there were significant differences between people.
However, I'm perfectly willing to believe that what you're seeing is quite real: it would be the very long wavelengths of red light, at the very edges of human perception. This would very likely cause similar changes in appearance as "actual" infrared.
Very nice observation, Daniella!
Petteri
--
Portfolio: http://www.seittipaja.fi/index/
Photo lessons: http://www.seittipaja.fi/lessons/
Lessons mirror: http://www.ivydesign.com/petteri/
[snip]
Infra-red is defined as wavelengths longer than red no longer perceptible to the human eye, so by definition, we can't. There's nothing intrinsically different about infra-red: it's just electromagnetic radiation, just light light. The line between red and infra-red is somewhat arbitrary; I also wouldn't be surprised if there were significant differences between people.
However, I'm perfectly willing to believe that what you're seeing is quite real: it would be the very long wavelengths of red light, at the very edges of human perception. This would very likely cause similar changes in appearance as "actual" infrared.
Very nice observation, Daniella!
Petteri
--
Portfolio: http://www.seittipaja.fi/index/
Photo lessons: http://www.seittipaja.fi/lessons/
Lessons mirror: http://www.ivydesign.com/petteri/
Jeremy Rosenberger
Leading Member
The surroundings are not emitting/reflecting as much IR (and surrounding wavelengths) as the foliage, and the filter is blocking (most of) the visible light reflected from the objects. Take the following (bogus) luminance values as an example.
Without filter:
With filter:
If you need more convincing, look at a 3W nightlight in an otherwise dark room, and compare that to the same nightlight in a room lit by direct sunlight; I think the light would seem much brighter in the previous case. Or look at the moon in the daytime sky compared to the nighttime sky; in the latter case the moon probably appears brighter. In both cases (certainly with the nightlight; I'm pretty sure about the moon) the amount of light emitted/reflected (visible in this case) from the object is the same, but you perceive it rather differently because of the surroundings (light vs. dark room/sky).
Hope this helps.
Cheers,
Jeremy
--
Jeremy L. Rosenberger
http://www.frii.com/~jeremy/
Without filter:
- foliage 5
- surroundings 8
With filter:
- foliage 1
- surroundings 0.1
If you need more convincing, look at a 3W nightlight in an otherwise dark room, and compare that to the same nightlight in a room lit by direct sunlight; I think the light would seem much brighter in the previous case. Or look at the moon in the daytime sky compared to the nighttime sky; in the latter case the moon probably appears brighter. In both cases (certainly with the nightlight; I'm pretty sure about the moon) the amount of light emitted/reflected (visible in this case) from the object is the same, but you perceive it rather differently because of the surroundings (light vs. dark room/sky).
Hope this helps.
Cheers,
Jeremy
--
Jeremy L. Rosenberger
http://www.frii.com/~jeremy/
Interesting.... I was sure they used passive systems that bent the IR rays into visible spectrum... I suppose things have got a bit more advanced then what I was taught 5 years ago.
Bry
Bry
Rods are b&w vision, cones are colour vision.
Although thats probably in the link!
Bry
Although thats probably in the link!
Bry
Actaully now seems the time to post something that I always thoguht interesting - the Minolta EVF acts like our eye - in dark lighting, it switches to b&w like our eyes do by turning only to the rods.. and in better lighting you get full colour vision.
Did Minolta model this function from the eye, or is it just coincidence?
Bry
Did Minolta model this function from the eye, or is it just coincidence?
Bry
Keith,
I remember reading somewhere that when you see little specks passing in front of your eye or something it can cause patterns and this is due to hardened particles (I think) of the liquid matter inside the eye bulb.
I don't know if this is the phenomenom you are referring to, but any relatively detailed textbook on vision should make some reference to it if it is, and you are interested in pursuing it
Bry
I remember reading somewhere that when you see little specks passing in front of your eye or something it can cause patterns and this is due to hardened particles (I think) of the liquid matter inside the eye bulb.
I don't know if this is the phenomenom you are referring to, but any relatively detailed textbook on vision should make some reference to it if it is, and you are interested in pursuing it
Bry
Petteri,
Significance is relative, but there are measurable differences between people.
Cheers!
Bry
Significance is relative, but there are measurable differences between people.
Cheers!
Bry
Barry L
Leading Member
I tried to supress the chuckle on this little thread commenting on the good Dr. before it erupted into a full blown smile without the side-effect of healthy laughter. I was unsuccessful. Nuff said.
Why does Sherlock always make one liners without reading the threadDr. Waston, explain why I can see the effect of the whitening
foliage with my R72 filter with my own eyes?
not nuff said
If you have a R72 filter, try it yourself..you will be surprised
or participating in the subject? I wanted to tell him the same
thing, but I was polite and waited for you. Why is this good Dr.?
Or maybe you know Daniella, nuff said.
Parker
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