Might be on a shoot up in Chicago this coming end of June. Right now it's between shooting some actual B/W film or IR Modified Alexas (XTs.) Both the director and I are very much so behind the Alexa as a system since it gives a look which we both feel will be beneficial to this particular project. However, information on the IR version is rather scant, aside from the brief tech specs and the info that you have to go ArriRaw.
In any case, If anyone has anything to look out for when working in IR with the Alexa I'd be delighted to hear it.
Specifically; lensing and focusing-- I am assuming they are some lenses in existence (possibly @ CSC with whom we'll be speaking) which already have the witness marks re-set for IR focus. Granted this may not be as big of an issue in the digital realm as there is a slight WYSIWYG -v- shooting IR stills (which I've done but rarely).
Next would be switching modes. As it stands it seems to me, and is yet to be confirmed by CSC, that it's either a Monochrome OR an IR system-- since there is a BLT filter for both-- but I am curious as the XT normally has a filter wheel, memory serving, that in reality it is just a switch from the IR to the B/W filter in camera.
Also; since you're dealing with a 2000 ISO system, are there any specific ND's which work best on the camera proper in order to control exposure. Especially when shooting IR in EXT locations.
Also; I know that dimming down a Tungsten feature will result in more IR exposure from it-- but are there any hard and fast rules for how much more you get since, obviously you can't really light meter IR (unless i'm wrong-- are there any ways to get an IR exposure reading these days? Haven't touched IR in a long long while)
In any case-- any info is much appreciated, as always, and I"ll of course also be speaking with CSC if we wind up going that way -- and who knows-- maybe try to sneak back to NY to test the thing out before we shoot.