IR?

Bucky

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I'm loving the IR pictures on here but its making me wonder
how and what is it?
like what does IR stand for and how do you accomplish it?
and help would be appreciated!
 
If you get lucky, Archangel will spot this and clue you in. If not, try a private message to him. He's very good, you know. Check out his 'Beach-scapes... " in the Landscapes section.
 
IR is infared. It's the part of the spectrum with longer wavelengths than red light, not visible to the eye. IR is done on digital by putting a filter on the the lens that blocks everything but infrared rays. It can also be done with the a filter and special (and expensive) infrared film.
 
thanks Torus......

yea basically as darin said its infrared.....the link below has the basic info on what IR photography is (although its a little dated).....

You can use an IR filter with film...... and IR filters are used alot now in digital photog.... mainly the Hoya R72, which you can order from most online photog shops....
IR produces strange colouring to images..... when b+w, turns green to white among other things... and can give you longer exposures in bright daylight....

http://www.cocam.co.uk/CoCamWS/Infrared/INFRARED.HTM

So its a fun filter to play with. ;)
 
Can you clarify this a bit? A lot of the IR shots I've seen look like they're in color (though the colors are IR) but the greens are still white. I read your post as to say that converting the image to black and white is the way to make the greens white.

Also... do you have a link to the beach scenes that Torus referred to? I'm going to grab an IR filter within a few weeks and can't wait to mess around with it.

Archangel said:
... IR produces strange colouring to images..... when b+w, turns green to white among other things... and can give you longer exposures in bright daylight....

http://www.cocam.co.uk/CoCamWS/Infrared/INFRARED.HTM

So its a fun filter to play with. ;)
 
rmh159 said:
Can you clarify this a bit? A lot of the IR shots I've seen look like they're in color (though the colors are IR) but the greens are still white. I read your post as to say that converting the image to black and white is the way to make the greens white.

Also... do you have a link to the beach scenes that Torus referred to? I'm going to grab an IR filter within a few weeks and can't wait to mess around with it.

The kind of color IR you see from Archangel is digital IR, and he has used software to bring the picture back to a kind of false color. You "white balance" off of green things to make them white, which shifts the colors accordingly.

Kodak also makes a color IR film, but it gives different results.
 
yea matt said it ;) ...... im using digital IR with colour..... my previous post may have been confusing...... i ment to say that green will appear white.... whether its colour or b+w.....
To get the colour IR look there's a few different techniques.... you can set a custom white balence to green..... this will give your IR shots a brown/blue look which you can stick with if you wish....... or you can swap the red/blue colour channels in ps to create a different effect.... here's a bunch of links to explain it better......

My beach scapes (i'v done a better job of some sand dunes i'll post soon)... HERE

For the colour swapping technique....... HERE

A variety of IR effects in a good gallery...... HERE
 
Just to clarify, it's not greens that appear white in IR, it's living plants that appear white because they relfect a lot of near infrared. It's totally conceivable that you can find green paint or something else that's green that appears black in IR. That's part of the fun of IR - discovering a whole new world because we're not familair with the reflectivity properties of materials in the infrared.

Color infrared photos come from a variety of factors and are often referred to as pseudo-color. When done digitally with a more shallow filter like a Hoya R72, a small amount of visible light makes it through the filter and can contribute color to an image. Also, the CCD's own RGB (or CMYG in some cases) filters pass different IR wavelengths by varying amounts causing the CCD to falsley perceive color in the infrared spectrum.

Visible light is 400 nanometers (violet) to about 700nm (red) Near-infrared is about 700nm-1200nm (which is the approximate limit of what a typical silicon based CCD will react to.)

Digital cameras have an IR blocking filter in front of the CCD so that the infrared light doesn't interfere with taking a good color photo. Because of this when using an IR filter, you often have to do long exposures (several seconds in daylight) with an unmodified camera. Some people mod their cameras and replace this IR filter with clear glass to make their camera extra sensitive to IR.

I hope this helps a bit with the background.
 

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