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Old 28th October 2003   #1
jujuman
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Default IR effect

Hi I'm new to this forum, and was not sure if this subject was discussed before.
Basically I'm curious to find out if anyone knows how to create that Infra-Red (IR) effect using Digital SLR?

Is there any setting that we can use organic to the camera? Or issit a post-processing effect?
Any tips?

I'm currently using a Canon EOS 300D
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Old 29th October 2003   #2
tomcat
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You will need an Infra-Red filter like the Hoya R72 filter, a tripod and some trial and error to determine an acceptable exposure time for your camera based for the lighting condition at the time of shooting.
 
Old 29th October 2003   #3
jujuman
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Thanks Tomcat.
So after shooting, is there any post processing to be done?
Do I have to change it to B&W for it to have that effect?
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Old 29th October 2003   #4
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do autolevel on the red channel, than extract it.
You will get B/W IR photo.
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Old 30th October 2003   #5
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Originally Posted by jujuman
Thanks Tomcat.
So after shooting, is there any post processing to be done?
Do I have to change it to B&W for it to have that effect?
The type of post processing needed depends on what kind of IR images you're after - B&W or coloured.

The common step for both is you should use Custom White Balance to take your IR photos. This will remove the bulk of the red cast from the initial image and this step is essential for coloured IR images though less so for B&W ones.

For B&W IR images, any of the usual post-processing techniques for converting coloured images to B&W images will do. There will be slight variations in the B&W effect depending on which technique is used, so it's your personal preference on which look best to you.

To get a more natural-looking coloured IR images, you would need to swap the red and blue channels to make the still reddish-looking skies blue in the final IR image. This is done in the Channel Mixer where the red channel is changed to 100% blue and the blue channel to 100% red.

Most DSLRs are rather IR insensitive and require long exposure times to capture IR images. Your 300D is probably the same as my 10D in this respect and would require exposure times of 15 to 25 secs. Use apertures of 8 or higher for sufficient depth of field because of the focal length shift in the IR part of the spectrum and because you need to prefocus with the IR filter off (can't see anything in the viewfinder through the IR filter).

If you have a P&S digicam, you might find it easier to take IR photos. Many P&S digicams, especially those with 2.1Mp CCDs are very IR sensitive and you can even preview IR image on the LCD screen before taking the shot. And you can even handhold the camera because the exposure time required is so short. I used a Nikon CP950 myself and I'm told that Canon G1 is especially good for IR photos. The main difference I found is that with the CP950, the colored IR images tended to be more like B&W.
 
Old 30th October 2003   #6
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So for P&S cameras, is there a need to put on an IR filter? Or just take the shot, then manipulate the image in post processing?
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Old 31st October 2003   #7
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Originally Posted by jujuman
So for P&S cameras, is there a need to put on an IR filter? Or just take the shot, then manipulate the image in post processing?
If you want authentic IR effects, you would have to use an IR filter whether the camera is a P&S or a DSLR. You would still need to carry out some post-processing to make the shots look their best but this is not the same kind of post-processing techniques as those used to create fake IR effects from normal photos.
 
Old 1st November 2003   #8
jujuman
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Sheesh, my first foray into IR effects was a complete disaster!
Went to Botanical Gardens to take some pics at about 530pm, but I guess I was too late to catch much light, so the pics all came out PITCH BLACK

Guess I don't really understand how to SEE in IR.
If I'm not wrong, the filter filters out most visible light, and only lets IR through. So does that mean that the surfaces have to be sufficiently heated up to have the CCD pick it up? Or issit that my EOS 300D is just too insensitive?

As for settings, I just lets the TTL meter take care of it. I just set my aperture to 6.3, and auto bracketed 1 stop. And the results are still pitch black.

I shot in RAW, so post processing wise, I had some flexibility. I maxed out my exposure compensation and curves. I can barely see the IR effect, however noise levels also went up such that it marred the pic.

Any tips? What am I doing wrong?
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Old 1st November 2003   #9
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The 10D/300D is not very sensitive to IR and it is not possible to get proper IR exposure using the camera's exposure meter.

You would get better results in bright sunlight because the camera is capturing reflected IR radiation from objects in the surrounding.

Before taking any IR exposure, take an exposure of a white or grey card with the IR filter attached, and use it to set the camera's Custom White Balance.

Set the camera to Manual mode and set aperture at f/8 or smaller and start with shutter speed of about 20s. You would of course have to tripod-mount the camera for such exposure timings.

Compose your picture and autofocus or manual focus with the IR filter off. Then put on the filter, set the focus to manual and take the picture. It is safer to set your focus to manual before pressing the shutter because the lens might autofocus when you press the shutter button otherwise. You may well be surprised that the camera can actually autofocus at such seemingly total darkness ! This may not be the focus that you actually wanted if you let the camera autofocus prior to taking the exposure however. Hence my suggestion that you switch the focusing to manual mode.

Check the image to see if the exposure is sufficient and adjust the shutter speed accordingly in subsequent exposures.

This is how I took my IR photos with the 10D. Try it! It's really quite easy to do !

Last edited by tomcat; 1st November 2003 at 12:41 AM.
 
Old 1st November 2003   #10
jujuman
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Thanks tomcat. I'm more encouraged after hearing this. Especially when I heard that my 3 week old 300D is not sensitive to IR

Will try it out and let you know the results!
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Old 1st November 2003   #11
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wud'nt it be easier to if u take a normal picture and IR it using photoshop...
IR filter it if u wanna use analog camera...
wat du you tink?
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Old 1st November 2003   #12
ckiang
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Originally Posted by Fundee
wud'nt it be easier to if u take a normal picture and IR it using photoshop...
IR filter it if u wanna use analog camera...
wat du you tink?
Like that where got fun?

Besides, we know that the less post-processing you do, the better. It's not that easy to do PS IR well unless you are a PS guru AND you know exactly how IR behaves.

There are filters/actions for this, but it probably won't be as authentic, coz such filters will never know what surfaces reflect IR, what absorbes it, at the different levels of absorption/reflection, and can only base on colour/luminosity to emulate the IR effects (usually to darken skies and lighten foilage).

Regards
CK
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Old 3rd November 2003   #13
jujuman
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Thanks for the tips Tomcat. My IR pics now turn out fine!
Have to play with the exposure a bit to get it right. Thanks goodness for digital, I can preview it 1st and delete those that arn't expose correctly.

If it were film, I guess 95% of the IR roll would've gone to waste
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Old 3rd November 2003   #14
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Originally Posted by jujuman
Thanks for the tips Tomcat. My IR pics now turn out fine!
Have to play with the exposure a bit to get it right. Thanks goodness for digital, I can preview it 1st and delete those that arn't expose correctly.
Congrats.. so post your IR pics leh
 
Old 3rd November 2003   #15
jujuman
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hehe ok here are 2 that i shot

Hafta go to my photo site, I cannot link direct

http://photos.yahoo.com/tmndeb

Under the "IR Photos" Folder
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Old 3rd November 2003   #16
jujuman
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tomcat, you mentioned in an earlier thread that, in order to get colours into yr IR shots, you jave to play around with the channel mixer
i.e. swap red to blue and vice versa

I've tried that, however, the pic just changes hue. I can't just get the sky to be blue

Any tips?
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Old 3rd November 2003   #17
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Originally Posted by jujuman
tomcat, you mentioned in an earlier thread that, in order to get colours into yr IR shots, you jave to play around with the channel mixer
i.e. swap red to blue and vice versa

I've tried that, however, the pic just changes hue. I can't just get the sky to be blue

Any tips?
What kind of colour cast did you get in your IR images? Is it a very intense red or light reddish? If you carried out a Custom White Balance, you should get a light reddish cast with a reddish cloudy sky which would appear blueish after the colour channels are swapped. A clear blue sky would however come out black. I can't tell from the pics you posted because they have been converted to B&W. Do note that the colours you get from swapping the colour channels would look rather surrealistic and not at all normal.

Maybe you can post some of your IR pics in their original colours so that I can check them out.
 
Old 3rd November 2003   #18
jujuman
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ok. posted up the original pics.
My original pics get a reddish hue. I tried swapping channel, but all it does is change hue.

Maybe I'm doing it wrong.
Could you can do something with them
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Old 4th November 2003   #19
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Originally Posted by jujuman
ok. posted up the original pics.
My original pics get a reddish hue. I tried swapping channel, but all it does is change hue.

Maybe I'm doing it wrong.
Could you can do something with them
Checked out your pic. It looked like you did not set a custom white balance when you took that pic. It is harder to get colors from such a pic because of the intense red cast. It can still be done to some extent through additional post processing but that pic in your Yahoo album is too small for me to work on.

I don't suppose that you took those pics in RAW format, did you? It would be easier to correct the white balance in RAW than in jpg format. Maybe you could either send me the original image file or post it in your Yahoo album and I'll have another go at it.
 
Old 4th November 2003   #20
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Tomcat, would appreciate it if you could advise how you use the channel mixer to process this photo. I don't seem to be able to have any colors adjusting the channel mixer. I know that it's not a good pic, but just one for you to teach your mastery. Thanks

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