Actually, a warming filter, like an 81A or similar light orange filter would work better than a yellow filter. In general, Polaroid films are more cool palette than warm pallette. The Fuji FP100C is slightly warmer, but in general more comparible to Polaroid 690. The easiest way to solve your problem with the bluer shadows is to use an 81A filter.
http://www.polaroid.com/global/deta...4488338434&bmUID=1153261809092&bmLocale=en_US
The US Polaroid website lists 690 as ISO 100. The boxes I have bought recently in California still indicate ISO 100. Unless they are trying a different batch, or something else changed in your location, I would think the ISO 125 indication was in error. I have shot boxes of 690, and always at ISO 100.
I have used this in a Polaroid printer, a 250 Automatic, and with a type 405 back, and results are fairly consistent. The rollers should not make too much difference, unless they are not clean, which can lead to uneven development. The supposed advantage of 690 is being able to leave it for minutes prior to separating, though I got my best proofing results with 90 to 120 seconds.
I don't know if I spoke to you on PDN Forums? There was a photographer going to Africa to do a project, and intending to use Polaroid cameras. If that was not you, that thread might be worth searching, though it was mostly about cameras.
Anyway, since I use more 690 film than other Polaroid types, perhaps this post answers some questions. If not, then feel free to ask more. You did not mention which camera you are using.
Ciao!
Gordon Moat
A G Studio
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