Is it worth getting a 'stronger' IR filter (than 720)

[robert]

Hi all,
I have 58mm R72 (720nm) which doesnt fit my new UWA zoom which tends to be my most used lens these days.
I am looking to get a 77mm filter and interested if anyone uses higher than 720. Its on a Canon 400D. The wood effect seems strong enough with 720nm and higher filters may just result in longer shutter times??

IR on digital is sooo much easier than using the old Kodak HIE- what a pain trying to load a new roll in the field!! I ended up mainly using the Ilford SFX and really like the results.

Interested in opionions and experience.
Robert PS anyone know the max sensitivity of this CMOS sensor?

[MCWB]

Robert, I presume you know that you won't be able to do false-colour channel-swap IR with R90 etc (900 nm) filters, just B&W. I got the R72 over the R90 for this reason, it's just nice to have the option sometimes. Also the R90 is more expensive, although neither is cheap for the 77mm version.

[robert]

Thanks- I thought the false colour option would be difficult, but not ruled out. I've not seen too many digital shots with anything higher.

Youre right about the cost for 77mm. I did a lot of searching and managed to find a guy with an Ebay store in the USA who does no-name (OEC) IR filters for less than $50 delivered!! He has 720, 850 and 950 nm available and over 30,000 feedback at 100% !!

[Big Red]

for that price you could buy all three.