rossb said:
Much is written regarding the advantages of the (horrifically expensive) "warming polariser" filters. Is there a profound optical advantage to their use, versus a polariser and KR1.5 in tandem
Regards to all
Ross
As Roxi331 indicated, check the discussion and search for "moose". Specifically to your question, yes you can use the filters in tandem and I have done so in the past. You can check my image in my gallery here at APUG:
(there was a url link here which no longer exists)
However, when using 2 filters you will now be using 4 "glass" to air surfaces versus 2. Subsequent to taking the above photo which in reality is remarkably sharp, I have used warm polarizing filters almost exclusively for my color transparencies. Using the single filter is also much more convenient. In addition, I have on order (backordered and waiting for the glass) the new Singh-Ray lighter brighter warm polarizer to fit the Cokin P filter holder (fits the round slot and can be used with a variety of lens threads up to 82mm with the appropriate adapter ring). Yes it is extremely expensive. However this filter will only lose about 1 - 1 1/2 stop of light as opposed to the more normal 2- 2 1/2 stop light loss of a regular polarizing filter by itself. This increase in speed for light transmission of about a stop or so is particularly useful for work with slower large format lenses.
Rich