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Old Apr 3, 2010, 1:28 AM   #1
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Default Musings from this week's lunchtime

Remember this picture from a few weeks ago? It was taken right before dawn and caught the sunlight reflecting off of the glass windows.



As I recall, someone pointed out in that thread the fact that the Wachovia sign should be coming down soon. Here's the same building yesterday at lunchtime:



No more sign! This isn't the most exciting picture in the world, but rather interesting in a second way. If you'll notice, there's a traffic light at the bottom center of the picture. It appears that the light wasn't working, but it was. I think it was on red the entire .8 sec. for the exposure, and didn't register through the R72 filter I was using, which I thought was interesting. It made me wonder what type of light bulb traffic lights have, I assume its not incandescent as I think I read they produce IR light?

Here's a composite I did - one frame that's in color transitioning to another frame that's IR. I thought it was kind of interesting, but am not entirely sure about it (it's well after my bedtime and I lose perspective on things, it could be complete rubbish). If nothing else, you can get an idea of the differences between a color and an IR b&w picture.



It's made up of this picture (.6 sec)



and this picture (1/800 sec.)



Maybe I should do the graduated filter on the layer mask on the diagonal instead of vertically? Any suggestions or comments, even if "it's not my cup of tea", are gratefully accepted.
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Old Apr 3, 2010, 5:52 PM   #2
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Quote:
Originally Posted by mtngal View Post
If you'll notice, there's a traffic light at the bottom center of the picture. It appears that the light wasn't working, but it was. I think it was on red the entire .8 sec. for the exposure, and didn't register through the R72 filter I was using, which I thought was interesting. It made me wonder what type of light bulb traffic lights have, I assume its not incandescent as I think I read they produce IR light?

Here's a composite I did - one frame that's in color transitioning to another frame that's IR. I thought it was kind of interesting, but am not entirely sure about it (it's well after my bedtime and I lose perspective on things, it could be complete rubbish). If nothing else, you can get an idea of the differences between a color and an IR b&w picture.



It's made up of this picture (.6 sec)



and this picture (1/800 sec.)



Maybe I should do the graduated filter on the layer mask on the diagonal instead of vertically? Any suggestions or comments, even if "it's not my cup of tea", are gratefully accepted.
Hi Harriet,

I think the reason that the light doesn't show up is that the red IR filter absorbs the red light, so effectively negates the light source.

Far from being rubbish, I think the composite is quite stunning. I was initially struck by how well the clouds blended together. I lack the artistic creativity to imagine how this technique could be used to greater effect, but I think that someone with more talent than I possess could really use this to make a strong photographic statement.

I also thought a diagonal division might be effective. Nice idea, and a clever use of some PP tools!

Scott
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Old Apr 3, 2010, 6:21 PM   #3
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lovely shotts Harriet!

The one traisitioning from color to B&W is a very neat idea and works well.

My first thought was the part where the tree in the center fades from color to IR emphasizes that the photo isnt split directly in half, favoring a slightly larger area of B&W than color. I thought making this split straight down the middle might have a greater effect because my eyes wouldnt keep peeling back to the transitioning trees and allow me to focus more on the rest of the photo faster.

Upon reprocessing my original thoughts, this would mostly likely ensure the trees are all on the colored portion of the photo and the image would lose its transitional feeling, having a harder line between the two pictures (being right at the edge of the tree line)

The diagnal transition might be cool to see as well or other alternate methods of conveying this transition just to see how it affects how our eyes are drawn to the many details of this image


Sorry for my ramblings here, I like this photo a lot



BTW Its glad to see something of Wachovia's fall
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Old Apr 3, 2010, 7:44 PM   #4
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Quote:
I think it was on red the entire .8 sec. for the exposure, and didn't register through the R72 filter I was using, which I thought was interesting. It made me wonder what type of light bulb traffic lights have, I assume its not incandescent as I think I read they produce IR light?
Harriet, most of the traffic lights in this area have been upgraded to LED lamps, but I don't think that has any effect on what you might see of the traffic light, as the IR filter transmits little or no visible light, so the light could have been yellow or green as well as red. IR sensors (and film) are sensitive only to IR which appears as white or gray, so anything that generates heat (like a warm body) will emit IR, or anything that does not absorb IR (like leaves) will reflect it, and will appear light (how light depends on the strength of the source).
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Old Apr 3, 2010, 8:52 PM   #5
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I know I responded to this earlier today, but am not seeing anything so.....

I think the merge is interesting. Something I would never have thought of to do. But, then I used to have problems doing my PSE assignments when we were instructed to majorly make changes to images. But, I think you did a fine job with this.

Interesting topic on the lights and what they are made of. This winter there was discussion of the lights that are being used nowadays that they are not hot enough to melt the snow that is collecting on them in the colder climates. There have been many accidents do to it. I don't understand that as if I was approaching an intersection that had no light, I certainly wouldn't go flying through it. But, the whole idea was something I'd never thought of.

Patty

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Old Apr 3, 2010, 10:54 PM   #6
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Interesting about the traffic lights - I do think this one has been converted to LED, and yes, I can see how that would be a big problem in the snow. Patty - you would think that people would be cautious when a traffic light isn't working because of a power failure, too. But it can get crazy on the local roads when the lights aren't working - there's always someone who doesn't want to wait their turn.

Thanks for the feedback, NMRecording. I actually chose to do the transition in the big tree as I was trying to show the difference between IR and regular photography. Perhaps it's too much - it does rather hit you over the head doing it that way. Maybe the diagonal wouldn't scream out so much.

But it's going to have to wait until I process some of the pictures I took today - I went looking for grand views and wildflowers, taking both the K100 with the R72 filter and the K-7 with a macro lens and a few others.
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Old Apr 3, 2010, 11:11 PM   #7
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Interesting about the Traffic light...
I don't know a lot about IR but it seems if the tight was on, it would have generated some heat, even if they were LED's you'd think it would at least be a different temp than the fixture itself and therefore shoe a slight difference in gray?
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Old Apr 3, 2010, 11:26 PM   #8
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Infrared filters don't pick up temperature changes (you can't use it to see if your house is weather tight). They mainly pick up reflected IR light, which is why trees/foliage are so light - they reflect IR. The R72 filter does let in a bit of visible red light, I think, it's not completely opaque when you look through it (though almost).

I had read that incandescent light bulbs emit IR light, but since I'm shooting through a very, very dark filter, I haven't tried any shots indoors. That was what prompted my question - if traffic lights had incandescent bulbs I would have thought I would have gotten some IR from them.

Another picture I took was interesting to me - I took a picture that had a number of American flags in the distance. In the color version the flags stood out against the dark trees. In the IR version, you can't see them as they fade into the light/white trees. Very strange.

P.S. Forgot to address one of Scott's comments. I shot these from a tripod, but they weren't quite exact. What I did after basic processing was to take both frames, then use CS4's action to load files into a stack and auto-align them. That got me two layers that had features lined up (along with the clouds, which since there wasn't that much time between them, hadn't changed all that much) and the ability to change their order (there's no background layer when you use this script). If you look at the two frames I used, there is some significant differences on each side, which is one reason I used a layer mask and a graduated filter to handle the transition. Layer masks are SO useful, just love using them.

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Old Apr 4, 2010, 11:13 PM   #9
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I'm late chiming in here, but I agree that your color/IR transition is fascinating. I like it a lot. The traffic light certainly is interesting. Patty is right -- here in the northeast, traffic lights always used to remain easily visible through big snowstorms, but with the new energy efficient LED traffic lights, it's a problem. She's also correct that anyone who can't tell what a light is signaling ought to slow down when approaching a snowy intersection! But of course, common sense doesn't occur to some.
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Old Apr 5, 2010, 6:39 AM   #10
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Fascinating photos, and fascinating discussion of IR... That merge is certainly eye-catching and thought-provoking!
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