Tips for Infrared?

Hello there!
Now it's my turn to try out that fancy infra-red photography Just got that Hoya R72.

Could someone give me some tips, guidelines, ideas etc for taking IR pictures? What's the best mode for shooting?

This pic i took with ISO800 and no tripod. I guess tripod and a lower ISO is a must?




K100D, kit lens.

P.S. Do polarizers still work with IR filters? Didn't have time to check that out properly.

Hi Jealousy,

Nice picture - I like the contrast between the 'heavy' tractor and the 'light' landscape. I'd crop a little off the bottom myself, but there you go...

I don't think a tripod and a lower ISO are 'a must', but the tripod might help with composition (you can compose the shot without the filter on, then add it once you're happy, rather than trying to see through a ver dark viewfinder). A lower ISO might help you get more contrast, which is what I feel this image lacks.

I had a quick play in photoshop, and found an adjustment layer with Levels set to 0, 0.82 and 248, then a Brightness/Contrast layer with brightness at -12 and contrast at +36 (but masking the shadows on the tractor) gave a more dramatic image. But whether it looks better or not is obviously a personal preference.

As far as I know polarisers work with IR, but I haven't tried them myself. I've got an IR filter, but don't use it too often. You have to find the right subject, and this one works well I think.

Dan

Good shot Jealousy. A tripod will certainly help, but a high ISO can give a nice grainy feel to an IR shot, so I wouldn't worry too much about trying to use the lowest possible ISO setting.

does the TTL metering still work or do you have to set the exposure without the filter and then put the filter on it?

message to self: try to resist buying an IR filter immediatly...

The metering may still work, but it's not necessarily measuring how much IR light there is with any degree of accuracy. Bracketing is a useful technique, but with digital you can also review the results on the screen. In glorious red....

At least with the K10D you can have a look at the individual colour channels on the histogram and probably get a better idea of the exposure. Not sure about the K100D.

Dan

With an R72 filter there will only be information in the red channel. The green and blue channels will be black.

My experiments with the Cokin P.007 89B filter (just did a few quick ones) found that although the green and blue channels are practically black, they do influence the RGB Histogram, which as far as I can tell is an average of all three channels.

If you get the histogram looking okay for RGB, then the red channel will be severely blown out. Using the three seperate ones allows you to see what the red channel is actually doing.

Perhaps it's different for the R72 filter?

Dan

physically there's no reason I can think of why a polariser wouldn't work, certainly for the near IR anyway. It may not give the same effect you expect though, depending on the polarisation of the IR light.

Yes, the R72 only lets IR light through, as that is beyond red in the spectrum there's no transmission at all of blue and green light. Logically we would then assume that the meter would read only IR light, but it's not designed for that and there may well be filters in place over the sensor. there's also the CCD filter to consider, so the sensitivity of the CCD may not be what we expect.

Real IR enthusiasts will have the IR blocking filter in the camera removed and replaced with clear glass. Then you have a dedicated IR camera. In the USA I notice that there is an IR version of the Fuji S5 pro marketed.

Us pentax Users would have to have a camera modified by a repair house. Has anyone actually had that done?

Also removed for CSI style forensics
Matt