Wednesday, March 21, 2012

DIY Infrared Flash talk

Okay, this is a nerd heavy post, just to let you know. Going to talk or ramble about my experiments in making an infrared flash for my infrared converted Canon XTi. (done by Lifepixel for those curious, and i highly recommend them) Basically, my desire for an infrared flash is so i can shoot in infrared in low light conditions with a flash, but since a regular flash is an annoyance in those situations (and banned in lots of places like that) i decided to search around for a do it yourself solution. I found lots of vague posts online via google that were of some help, but mostly instructed to stick some sort of ir filter or exposed and developed slide film over the flash, but not too close as the heat from the flash can melt the filter. So with a lot of trial and error, here is what i did.

Version 1. Basically a thin plastic ir filter in a LumiQuest FXtra Gel Holder, which was then held to the camera with velcro. Electrical tape (you'll hear these words a lot, heh) was then used to seal up any escaping light leaks. Not horrible, but a pain to take off and put back on. So i started to look at other routes.

Version 2. (the one that is up and to the right, not on the flash) I took the filter from Version 1 and put it over a STO-FEN Omni-Bounce (found a couple cheap on amazon, like a fourth of the cost listed there) and wrapped the rest in electrical tape. Thought about painting the exposed plastic on the Omni-Bounce, as light did come out where tape didn't cover. Then i decided to try version 3.

Version 3. Pictured on the flash above. One my now unused Hoya glass ir Filters, attached to an Omni-Bounce that was cut in half to get the filter closer to the flash head for a less narrow beam. Then electrical taped around to prevent light leaks. If i spent more time on this one, i would epoxy or glue the filter better on the Omni-Bounce and pain the Omni-Bounce, as the electrical tape is kind of hinky looking, and with the tape i wrap it around the end to keep light from getting out. So far, this is the best i've done though, and it works great.

What i did find after all this though, is Quantum makes accessories for their flashes that does all this much better, but at a much higher cost. Here is a great write up on that.  Maybe in the future i'll work on getting that, as the flash head alone is pretty awesome, and being a better IR flash just adds to it. It's a head that needs a pack though, so instead of just a head, there is quite an investment going in. I guess i'll update if and when i do that.

So anyway, more about what i've done so far. Some of the results i've found while using the flash is interesting. Challenging, but interesting, to say the least. Playing around in my kitchen last night (which is messy, so i'm not posting those pictures), i found that with the flash being normal with no filter, the light was good, but no reach it seemed. With filter on, it lit up the whole room. Seems counterintuitive, especially with the filters looking black to the naked eye. White balance is hell too, if you balance for the flash, any other light that has ir wavelengths has a different color. For example:

I took this one at a local university event, and had the white balance set to the flash, so what the flash lit looks close to black and white, while the stage lights have a very yellow tint to them. It's a neat effect, but unpredictable. This is also the kind of situation that calls for not having a bright flash going off while taking photos. Whats not colored yellow was hit by the flash, but not visible or annoying to anyone there. All that you can see if you look directly into the flash is a dim red light, barely visible.

Another from the same night with the version 1 filter. kind of looks sepia toned, and was also well lit by the flash. Did a great job of freezing action, even though the camera wasn't set too high of a shutter speed.

A shot from version 2 of the filters, where you might be able to see how the flash lit and helped with action. Panning with the runners, flash froze them and let the more distant blur. The colors are also from balancing the white to sunlight, with the flash adding a little blue. I know, it's screwy, but if balance isn't set right, everything is red. While interesting, and able to changed in post, it's nicer knowing what to expect before hand. What you can't see here is that the street signs reflected a lot of light, lit up from even far away. This event also showed me why i'm tempted about the Quantum flash, it fires machine gun style, while my flash has a poor recycle speed. If i want to do IR shots of action, i will miss a lot of them. Not even mentioning the fact that the XTi has a small buffer and less frames per second able to be shot. I think if i do end up getting the Quantum, and eventually the Canon 5D mark 3, i might get either my 7D or 5D converted, as they have more capabilities than the XTi.

So to wrap up, enjoying IR photography a lot lately, how it's surprising and letting me see in new ways. This weekend there is a Bluegrass festival in town, with several bands playing, and if i'm able, i hope to try out the version 3 flash with performers. Should be interesting.