Shooting with R72 Infrared Filter


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Gerald Lam CK

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Jul 2, 2009
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Hi, I'm keen to get a R72 IR filter to explore IR photography. But as i googled to search for how to use it, i found this advice from a foreign website.

Basically step 1 is to buy a tripod. A good one. And then get one of those $5 remotes off ebay. Long exposures mean no touching the camera - you'll make it wobble and ruin the shot. If you're cheap like me, you can use the self timer - but the beep beep beeping gets old really fast, as does the 10 second wait.. The quality of the IR filter *really does matter* regardless of what people say about using bits of old floppy disk or junk, they IR filters block /let through a really specific wavelength of light, so dont be tempted to buy some cheap crappy one. Hoya 72, or wratten 89b (I think its 89b, might be wrong) are ones to go for. I use an R72.

Step 2, set a custom white balance. With the camera set to awb and the filter on, correctly expose for something you want to be 'white' in the picture - usually a patch of well lit grass. Defocus the lens, or, what I do, because the exposures are so long I handhold it and deliberatley move the camera about so that the resulting image is just a blur - this is fine because we're only using it to tell the camera what 'white' is. Its like expodisc for the 'I dont have an expodisc' crowd.

Step 3: Put the camera's WB mode into 'custom' then in the menu go to the '2' menu, scroll down to 'Custom WB' and hit 'set'. Then scroll through to the image you made in step 2, and hit 'Set' again. This sets the custom WB. Yay!

Make sure you get those in order! I didnt a bunch of times - set the wb setting to custom *first* THEN choose a custom WB image.

Step 3 - compose your image, screw on the filter. Some people say you have to manual focus with the IR filter on, I've never gotten that because while the sensor does have anti IR glass over it, (which is why we have long exposures) the AF sensor doesnt have IR blocking glass over it - so it can AF fine even though you now can't see anything through the viewfinder having put the R72 on. Also - Shoot in raw mode. If not always, definetley now for IR


Step 4 - Take your picture! You'll be making a long exposure. Typically dont be tempted to open up the apeture to lower it, I shoot at f8 a lot, at iso 100. Low iso is handy because long exposures generate a lot of noise as the sensor heats up from use etc. Although, I wonder if you get less noise by using a higher ISO and not having the sensor being in use and therefore heating up/creating noise? Someone else will have to answer that one. Anyway, use your cable/remote release to fire the shutter, for extra points turn on 'mirror lock up' in the custom functions, it eliminates camera shake from the mirror slapping up. So, lock up on, press remote button once, mirror goes up, press it again to fire the shutter and make your exposure.

Step 5! Smile, be happy, take pics, go home. Make cup of tea. Feed dog. Load images onto computer and.. here's where it stays complicated. I use canon's DPP (digital photo pro) software as my first step, because photoshop/lightroom can't handle a white balance set as low as we just set ours, so they bump it up to 2000. Passable, but not really great, especially as we went to so much trouble setting a custom WB on location. So I use dpp which doesnt change the white balance, and export to tiff, then load that tiff into photoshop. DPP is free but a bitch to find, do some googling and you'll get it tho, prolly an old version, then download the updater and you're set. Mine didnt read RAW until I updated it. Anyway I digress..

In photoshop, with your nice tiff, its time to do the whole levels thing, wherby you adjust the levels individually for each channel (choose them from the drop down box) by moving the sliders to the start and end of each of the 'mountains' then OK that and hit ctrl E to flatten the layers

Next, go to channel Mixer, and invert the red and blue channels. That means, set the 'red' channel to red = 0, green = 0 blue +100, and in the 'blue' channel' set it as red = 100, green = 0 blue = 0.

Looking better now, right? One more thing.

use a 'curves' adjustment layer, and set the black, white and grey points using the eyedropper tools. Play around setting the points until you get a nice image and presto - you're done. Unless you're like me incase you try setting that curves layer about 20 or 30 different times before you get it just how you like it. It can take a while but play around!

Put a dumb frame around it like I did and show your friends!

Notes:

Did I mention the long exposure times? You can try using the 'noise reduction' custom feature, tbh I never bother, I dont think it does that much..

Its true you can use software, but The Nug - that just looks like a negative to me? Maybe i'm wrong but it doesnt look like IR. You can get weird effects for sure, but IR is light that is invisible and distinct from the human eye's wavelength (another reason you should NEVER EVER look at the sun through an IR filter - it wont dazzle you or look bright but it'll still burn the **** out of your retina - you can't see the UV rays that give you sunburn either, dig?) so messing with full spectrum images won't ever let you replicate IR, just kinda get close ish..


Sorry if this was overly confusing, I havent slept in about 20 hours!

EDIT - the hotspot thing, I totally forgot to address that..

Thats another post about as long as this one - short answer is dont shoot fully zoomed out on the kit lens. The closer you get to the 55, the less that hotspot is gonna be there..

Lazy answer as to how to do it in post - make selection in quickmask, feather selection, hit ctrl shift i, save selection as, tweak levels, load selection, lower saturation, load selection, edit curves manually (no eyedroppers this time) and then reopen the hotspots levels adjustment settings and tweak more..


I'm kinda confused by step 2 though...how to set custom wb?
 

Sorry another query..so for IR photos, it's a must to pp in ps? I read about the channel swapping thingy.

Not really unless otherwise you want the sky blue ;) I love the way it comes out of my camera most of the times. I do have channel swapped pics to get more dreamy looks.
 

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