muratcangokce wrote:Hi fellas...
I am looking to solve out how can I clean up the IR pollution that could disturb while using heavier NDs. I have regular Tiffen WW ND filters from 0.3 to 1.2. I didn't buy heavier than these because I know I could stack them. But as you know especially when using any ND heavier than 0.9, it is better if they are IRND.
In my case, I searched on forum and whole web but I couldn't find any comparison between Tiffen IRNDs and a combination of Tiffen T1+Regular Tiffen NDs. I am planning to buy a Tiffen T1 to cut IR pollution since I have a set of regular Tiffen NDs but it would be good to see how they are working together.
If you have any thought about it please share with me..
Thanks a lot.
You will take a hit in resolution by stacking an IR + ND vs an IRND (noticeable on long lenses) and without an AR tray in something like a Panavision mattebox, you increase the chance of internal refections in the filters. Also, I believe that any dichroic filters shouldn't have any other filters in front as you can get some weird IR refections.
You also use up an extra tray in your mattebox. In the case of a 2 stage box w/ 138mm ring, I usually go for IRND so I can either play glass diffusion, a grad or stack a heavier ND if required in addition to the base ND1.2 or 1.5 and a 138mm pola. If you are working with a 3 or 4 stage production matte box, then that is less of an issue.
Finally, since you already have the set of NDs, adding a separate IR filter certainly is the best value but I would consider it unacceptable for rental. You could look at adding just an IRND 1.2 instead.