Infrared photography with Canon EOS 20D

Has anyone used the Hoya infrared filter with the Canon EOS 20D?

Been trying to find photos of infrared with this camera. Thx

You will find some here:

 

http://www.pbase.com/wintermist/infrared&page=1

thanks a lot!

You may encounter problems attempting IR photography with this camera. Many digital cameras have IR filters (called a hot mirror) built in to improve the image quality, which makes them useless for IR photography. Check <a href="http://infrareddreams.com/how_to_shoot_ir.htm">this link</A> for more info. I found that most later Canon digitals have this and do not work well for digital IR work.

 

- Randy

"I found that most later Canon digitals have this and do not work well for digital IR work. - Randy"<p>So how does that explain the IR pix in Mark U's link?

Everyboy is invited to see

 

the online modification on Rebel 300D, you can learn what is all about this modification; maybe a stomach bypass surgery would be easier, too much risk:

 

http://ghonis2.ho8.com/rebelmodnew.html

 

Below is another link with some more comments:

 

http://www.dcresource.com/forums/showthread.php?t=1627&page=2

I suspect the pix in Mark's link were made using a pretty long exposure time in order to

get beyond the 20D's internal (and imperfect) IR-block filter.<P>

The photo below was from my sony, which has a mode that flips the IR-block filter out of

the light path. Shot at 1/60 sec, ISO 100, IIRC.<BR><P>

 

<center>

<img src= "http://pages.sbcglobal.net/b-evans/Images9/IR_Web/image/silos1.jpg">

</center>

Because infrared is heat, modifying a camera will increase your picture noise (thermal noise) at CCD level, so if you replace the filter, my recommendation will be to use a lens filter to block infrared when the camera is not used for that purpose.

i've read somewhere of replicating an ir look via photoshop, can't remember quite where though. luminous-landscapes.com?

channel mixer --> monochrome --> red 160, green 140, blue -200, YMMV

Infrared photography =/= heat at all. We are talking "Near-Infrared" when talking IR photography, which is just beyond the visible spectrum of light. Heat is in the very far IR range, which is not recordable on CCDs, or IR film for that matter.

BTW, you can look at an "infrared looking" image made trhough photoshop here

 

http://www.photo.net/photo/3037571

 

It wasn't made with that in mind but it looked quite a lot like this afterwards. I used channel mixer with 140%red and -40% blue. I Guess I'll try previous poster's idea but I think it might bring in artifacts, being quite extreme and all.

There seems to be some confusion here. EM radiation (IR, Light, UV, X-ray, Radio) is all one thing. It is just different frequencies. Heat is NOT EM radiation; it is a state of matter (how energetic the atoms are). Where they interact is that energetic atoms give off photons. coolish things (say room temperature) give off photons mostly in the deep IR section of the EM specturm (ie. low frequency). Hotter things give of photons in the light region (which is why flashes etc. are measured in color temperature; that is the light given off by objects at that temperature).

 

So in order to see the light given off by room temperature objects, you need a sensor which detects deep IR. Alternatively, room temperature objects which REFLECT radiation from warmer sources (like the sun @ 5500?K or so) you can use IR or standard sensors.

 

Note this is a very simplified explanation, but I hope it helps.

do a search in google for

 

infrared astronomy 20d

 

and you will turn up a bunch of vendors of modified cameras with warranties, as well as a lot of tech info that dispels some misinformation posted above

Understood, infrared is part of light spectrum!

 

Now lets comeback to practical world.

 

When IR intersects with any objects it is absorbed very easy, it generates heat, maybe provably (I say provably) more heat than any other color of the spectrum. If you want just seat in front of an IR spot light, after a few minutes you tell me the results.

 

That is what exactly happens when these rays hit the CCD, they produce heat and the heat increases the thermal noise on the CCD. That is the same reason because Canon installed that filter in front of the CCD. Final product is a noisier picture.

Thank you all for the many links to ir-photo's

Many Thanks..

 

Rich

<a href="http://www.phototalk.net/wb2lfy/albums.php"><b>wb2lfy@msn.com</b>

</a><br>

"When IR intersects with any objects it is absorbed very easy"

 

Depends on the object, Tree leaves for instance are more reflective of IR then they are of visible light. Hence the lightness seen in IR photos.

 

"it generates heat maybe provably (I say provably) more heat than any other color of the spectrum.

 

Go ahead and prove it then. Until then I will keep believing that energy absorbed from a photon is proportional to the frequency (E = Hbar F). Thus visible light will produce more heat per photon than IR.

 

"If you want just seat in front of an IR spot light, after a few minutes you tell me the results."

 

I get warm, but not a warm as if I sit in the sun which is more in the visible spectrum. (by the way I KNOW the comparison is faulty, but then so is yours).

 

"That is what exactly happens when these rays hit the CCD, they produce heat and the heat increases the thermal noise on the CCD. That is the same reason because Canon installed that filter in front of the CCD. Final product is a noisier picture."

 

Here we agree. With the caveat, that Canon did it because they thought that IR was not useful for picture taking, so it didn't matter if they filtered it. For _most_ people they are right; I just wish it were an option.