Saturday, June 2, 2012

Re-visiting image experimenting

For a while now I've been interested in the look of IR (infra red) photography but I am also aware of its limitations - need to use a tripod and having to frame/focus before putting the IR filter on the lens. Add to that the issue that a lot of modern lenses don't even have an IR focus indicator. Probably would be easier to get a D-SLR modified to take just IR photos but I'm not in a position to do that.

To combat some of this I started experimenting with using a flash so I could do hand-held IR photos. Framing is still a slight issue as there is no way to view through the lens with a Wratten 72 filter on the lens, so framing is an approximation until I devise a viewfinder to attach to the camera. The focus is taken care of by hyperfocal focusing on my 20mm wide angle that has both a DoF scale and an IR focus indicator. On the flash I place a pair of "Red-AWB" gels to keep it into the red scale and not skew things too much colour-wise.

Here is an example taken from my garden to show the effect. The photo direct from the camera is all red (due to the solid red IR filter) and I converted it to black&white in Lightroom. Other than the conversion and re-size for the web there have been no other modification to the image.

Here are a few more photos to show the effect of "hand-held flash IR".

I will be refining this technique some more and want to use it on some architectural subjects.