A good tip on Infrared photography and white balance

[tomtom]

I wanted to share a good tip on digital infrared photography with you. Basically, in digital infrared photography, you only need an IR filter such as HOYA R72 to shoot infrared photos with your regular digital SLR camera. I am using Canon EOS Digital Rebel XT (or EOS 350d). There's a brief overview on my digital infrared photography site for beginners along with some recommendations.

But here's the best thing about digital IR photography: the key to taking stunning digital IR shots is really setting the right white-balance. Basically, you need to take one shot with automatic white balance, and then use that photo to calibrate all following photos' white balances using that first picture taken, so:

1. Take a regular photo with automatic WB
2. Use Custom WB mode, based on the photo you just took
3. Shoot more IR photos (which now come with stunning, nice white balance)

Note: you will need to shoot with pretty long exposure times in order to capture as much near-IR light into your camera. This is because most digital SLR cameras come with IR-block filters. With long exposure times, however, some near-IR light will still be captured.

Examples below.

Here's an example of an image that is taken without the aforementioned white balance trick:


Note that trees are purple and the photo does not look balanced in terms of red-green-blue colors (white-point is off).

Here's an image that is taken with pre-calibrated, custom white balance:


Notice how pre-calibrating (using the first photo as a basis for custom WB) greatly improves the look of the IR images.

Hope it was useful I'd love to read your feedback on this tip.

[nemesis256]

I don't get it...If you shoot one image with auto white balance, then use that setting on the following images, isn't the setting the same as using auto white balance anyway?

One thing I read about IR photography and white balance was to meter it off the grass to offset the red in the leaves.

[rosserx]

In the latest issue of After Capture is a very interesting article about shooting infrared. I suggest you read it. There's more to it than slapping on an IR filter and adjusting the white balance. You need to have your camera's infrared blocker disabled or removed by a camera shop that can do that sort of thing. Here read the article then you can argue with me http://www.rangefindermag.com/storag...d_Dohrmann.pdf

[Sarangu]

You can just take IR photos with the IR filter on. It just means that you need to take longer exposures. That is because the IR blocker in front of the sensor blocks most but not all IR so a longer exposure would increase the IR hitting the sensor. By removing the IR blocking filter at a shop, you can take IR photos at normal shutter speeds. I hope that was helpful. I just got an IR filter and was at a loss myself. I've only recently discovered that the white balance needs to be adjusted because if you do not do that it will be just as though you're using a very strong red-tinted ND filter. With white balance adjusted you get results like the ones tomtom kindly showed us. Calibrating white balance on green seems to work quite well. The filter option seems to be quite a good one so far, as modification of a camera is quite expensive and risky. I would only recommend sending in either an SLR you're not using or a cheaper P&S. In some forums I heard of people eager to send in their Canon 5D's. I was getting shivers....

[inkista]

Originally Posted by nemesis256

I don't get it...If you shoot one image with auto white balance, then use that setting on the following images, isn't the setting the same as using auto white balance anyway?

He's not using an auto white balance--he's using a custom white balance.

One thing I read about IR photography and white balance was to meter it off the grass to offset the red in the leaves.

This is because chlorophyll reflects infrared light. It's the closest you'll get to white when looking at infrared, which is why white-balancing off of it works the best.

The red cast is because the infrared filter isn't 100% efficient and still lets in some wavelengths that are at the visible end of the spectrum (i.e., red). This is actually a feature, not a bug--if it was completely efficient, you wouldn't be able to see through it and it would be hard to compose and focus.