Posted 08 October 2007 - 07:02 PM
I am shooting with 5279 in exterior work for a film and I want to shoto at 4.0 on the stop and will be using heavy ND which I have done before and NP but was testing a couple things and in a couple i got some color shift. Not so much on a single ND85-1.8 btu combining two NDs. I u nderstand this as adding characteristics of the filters but wanted to ask peoples experince in this.
Posted 08 October 2007 - 09:00 PM
Posted 08 October 2007 - 09:10 PM
Kinda like this:
But the 'oil' is the gap of air between the two filters - same phenomenon, different set up ...
Edited by Nick Mulder, 08 October 2007 - 09:14 PM.
Posted 09 October 2007 - 01:13 PM
Thanks for the replays.
I printed a test of 5279 using an ND85-1.2 plus a ND3 and had no problem so most probable thing i will go with a 1.8ND85 and avoid extra glass...any thoughts?
Posted 09 October 2007 - 01:39 PM
A good demonstration of this sort of interference is "Newton's Rings". In this case it's a spherical glass surface (like a lens) touching a flat glass surface, therefore you get concentric circular bright and dark rings.
I dont know if you were doing it but if you sandwich glass or resin filters together closely (matte box type filters, not screw ins) you'll get interference patterns about the wavelength...
Posted 09 October 2007 - 01:55 PM