Oh wow-- there's about a dozen threads on this, some pretty arcane and complicated.MIKI-814 wrote: I'm lost... in a Canon 814AZ-E, what should I do to shoot correctly a Plux-x? and Tri-x? Cancel the filter or not? And what about in a Canon 310XL?
They're interesting, though, because none of this was figured out until the last few years or so. The earlier magazines at the time all got it wrong-- mostly because there was only one daylight color stock available and the problem never came up with that one ('G' film) because no one used it much seriously.
In a nutshell--
1) If your camera is a SMPTE compatible one (the 814 probably is), then you can run the new Plus-X correctly, and possibly Tri-X, but in most SMPTE cameras Tri-X will be overexposed a bit. That's because-- keeping it simple-- they're both "daylight" cartridges, meaning they are notchless and they push in the filter pin. The filter's already cancelled. They rate both films at 100 ASA-- good for Plus-X, not so good for Tri-X.
I have a feeling the 814 will read Tri-X correctly though, because it can read higher speed notches (?) If the 814 can read 250, it will read Tri-X at 160, which is OK.)
2) If your camera is not a SMPTE, you can run Tri-X correctly, but Plus-X will be underexposed a bit. These cameras will rate both films at 160, because that's what they are notched for (to be precise, Tri-X is notched for 250, but most cameras will only go as high as 160.) Either way, you can't control the filter-- it's automatically out, always.
The reason for all of this complication? Blame it on Ektachrome 'G' film. On later non-SMPTE cameras, pushing in the filter pin cancels the 85 filter as well as the correction that was factored in to compensate for the filter. That allowed daylight 'G' film to be rated at 160 ASA.
With SMPTE cameras, the filter is cancelled, but the "correction" remains, so to speak. This enables the camera to effectively meter film at a lower "daylight" ASA. That's what's happening, effectively, when the filter is in place. Only with the SMPTE camera you can do it with the filter out, which is what you need to do for "daylight" non-tungsten film.
But these cameras wouldn't run 'G' film correctly, because Kodak insisted that this film be notchless, so that you couldn't use the 85 filter, even though it would work with that stock. They didn't give you the option, so most SMPTE cameras wouldn't run it correctly. They ran it at 100 ASA. Thus the rise of simpler, non-SMPTE "xl" cameras that could use 'G' film.
The 310 is a whole different world in itself. That's the subject of about two dozen threads! But the 814 should be able to read both B/W stocks correctly. Many other cameras will not-- it's one or the other but not both.
