Which Infrared filter?

mdebets

After having played around with Infrared film photography a little bit, I now also want to try it with my 30D and 40D.
When I was looking at filters, I came across the Heliopan filters, which come as 665mm, 715mm, 780mm and 830mm.
While I understand the basis of Infrared photography, I#m not too sure of which filter to buy (I presume the 830mm would be the best).
Could anyone give any advice on which one to buy?

swingking

830mm is best for black and white IR photography

sineadw

Just back today from an IR workshop with Monochrome Meath (which was brilliant btw - would have absolutely no hesitation in recommending it ) so I'm all loved up on the IR. I'd be going for the 5695nm one for starters (I assume you mean 695 and not 665...). The higher end ones will lead to very *very* long exposure times. Digital exposures are much longer than films anyway. The heliopan 5695 is rated the same as the R72.

Of course, depends what effects you want

sineadw

swingking wrote: »

830mm is best for black and white IR photography

Heliopan rates differently to the other filters. 830 is *very* strong. I've tried a similar filter on the 350D and 5D and even with 3 minute exposures at f1.4 and 3200 iso I was getting zilch. It blocks out almost all light. It's more like a 900nm in normal ratings.

sineadw

Sorry OP - just re-read your post - there is a 665 but the 695 (which you haven't listed) is the one I was on about.

mdebets

Thanks for the advice.
I'm just trying to get my head around the IR photography.
Is it correct to say that a less stronger filter (e.g. the 695mm) would be better for an unconverted digital camera, while a stronger would be better for a converted digital camera or a film camera.
Would there be a visible difference with a film camera if the strength of the filter would not match the sensitivity of the film (e.g. if I would use an Efke 820 film with a 695mm filter) or would that be negligible, especially when shot with a Holga?

sineadw

You don't need a filter with a converted digital camera. They're MUCH quicker than a normal digital camera. Film is a lot quicker too. I was shooting today (partly cloudy) with Efke Aura rated at 50 ISO with an R72 (heliopan 5695) and I was still well under a second. With my digital yokes I was pushing more like 30 seconds at very high ISO. Some digital cameras are better (worse) at filtering IR though - the 30D isn't that slow afaik, but a lot slower than the D50, which can get almost handheld speeds with a hoya R72 in place.

Films are rated to cut off nm levels. So Rollei and Efke are both cut off at 820. But not all films peak at the same level. Efke peaks at 750-800 so teh 5695 (R72) is a good choice, but you could go a bit higher. Don't go all the way to 820 though or the film is getting no light that it can register. The Heliopan 5695 (R72) would give a strong Infrared look with Efke, but will give a more subtle one with a red filter for instance, or a lighter IR filter. Whereas using a red filter on a lower IR film like SFX would only give a slight IR look. You really need the Heliopan 5695 (R72) for that. Not sure if that answers your question?

Not sure about a Holga. There was someone at the workshop shooting with one today, so hopefully I'll see that in a while You'd have to be very careful with light leaks etc.

Fionn

i've delved into the world of Infrared, so far it's been hit and miss
some have come out ok, but others are a bit of a mess!! Whatever i'm doing in the processing i cant seem to get the blue in the sky properly - havent tried any BW yet.

does anyone know do you have to create a custom white balance for each session or would the custom white balance recorded do for each time you record IR images?

I've been reading about DNG files and how they can be used together with RAW IR files to do nearly all the processing in camera. Have more reading to do on that subject tho!

below are two examples of my efforts so far.