What’s Your Preference?

ishootRAW · #1 (**permalink**) 09-30-2011, 07:27 PM

I could not decide if this was technique or gear, so I'm posting it here under the assumption that the mods will move it where they feel best.

For the infrared geeks here.

I just bought a $9.99 IR filter to try. However, it's not working. What I'm getting looks nothing like what you see online. Yah, yah that stuff is processed and I went through several tutorials. But It's just not working right, trees are still green, etc, it looks just like a b&w pic with the red saturation turned up. Now upon closer inspection the filter seems iffy. It's supposed to be 720nm, but in sunlight, I can kinda see through it, all be it with a heavy red tint.

So, am I doing something wrong? Or did I get what I paid for and need to suck it up and get a Hoya r72.

inkista · #2 (**permalink**) 09-30-2011, 07:32 PM

What images with my Hoya R72 look like SOOC, if I don't do any custom white balancing, etc.

Canon XT/350D, adapted C/Y Distagon T* 28mm f/2.8.
iso 400, f/8-ish, 30 seconds. Tripod, cable release (obviously).

Note how the water's black, and the trees are lighter than the building. Visible light shot:

Yeah, any filter that's just $10 is pretty much suspect to me.

kcoppock · #3 (**permalink**) 09-30-2011, 11:08 PM

Got what you paid for, I'd say, unfortunately. If you can see through it even vaguely there's something wrong. My Hoya R72 is completely opaque unless I'm holding it to a very strong light source (like the sun), even then it's faint.

ravncat · #4 (**permalink**) 09-30-2011, 11:26 PM

I think i have a hoya r72 as well, and it's not as good as my wratten 89b. I found trees were giving me the right IR response with the r72, but it was certainly letting too much red light through to the sensor.

Take shots of trees to make sure it's really passing IR light well.. I get better results with my 72 in black and white shooting because the red is so strong.

ishootRAW · #5 (**permalink**) 09-30-2011, 11:53 PM

The plot thickens

The filter works great with my S95, but not at all with the 50d. Will post some pics when I get home. Anyone have an idea as to what is going on?

Biomech · #6 (**permalink**) 10-01-2011, 12:19 AM

Never looked into IR photos, although they seem pretty cool. But looking at filters I've just seen this, maybe this explains it:

Hoya 52mm Infrared R72

Used for photography with infrared films or IR sensitive digital cameras, Infrared filters absorb the visible spectrum, allowing clear infrared imaging. Typical uses include industrial, scientific and forensic photography, as well as artistic effects in landscape or architectural photography.

Skoropada · #7 (**permalink**) 10-01-2011, 12:30 AM

Did you remove the internal IR filter on the 50D?

ravncat · #8 (**permalink**) 10-01-2011, 12:53 AM

Yeah - the 50D (and most newer cameras) have much stronger IR filtration in the low pass filter stuff internal and built onto the sensor.

My older d70 was great for IR out of camera (other than hotspot issues). Chances are the s95 doesn't have such strong internal IR filtration.

Mike367 · #9 (**permalink**) 10-01-2011, 12:58 AM

Digital cameras have a filter in front of the sensor to filter out IR. (otherwise it screws up the color rendition) Some are more effective than others. If you filter out all the IR, and then add a filter that filters all visible light (allowing IR to pass) you get... a black frame.