ND + IR filter vs. IRND filter

[Bryce Lansing]

I'm thinking in investing in some 4x5.65 ND filters, but it just dawned on me that with all this digital now days, the IR issue when using NDs may be a reason not to invest in non-IR ND filters.

I know they make an IR filter to use with NDs, but also make IR-ND filters. Are IRND filters better than using an IR filter with an ND? I guess theoretically, your hooting through less glass, but is it enough of a reason to not buy regular NDs?

 

[I Bloom]

I found that the ND + IR CUT filter is a pretty good solution. There are some minor color issues with wide lenses but, often the effect of the IR CUT on the image is really nice. Schneider Tru-cut works especially nicely.

But for clear sharp images, especially landscapes with wider lenses, there really is no substitute for good mirrors on the Red. They look amazingly clear and sharp and the color rendition is perfect. Panchros especially are really amazing, and I would consider using them on film as well.

IBloom

 

[Steven Parker]

Some people feel that the IR/ND combos are best the solution since the amount of IR cut is tuned to the density of the ND; also, a combo filter takes one slot in your mattebox instead of two.

IR filtration is generally only used on ND0.9 and higher with the Red; so you could get a straight ND0.3 and 0.6 to save a little money, then combos for the higher densities.

 

[Jason Joseph]

hi
i was wondering what effect does IR do on your footage?
we shot with some 2 x ND4 filters on our nikon lenses and the picture turn out very blueish, is this the IR problem that everyone speaks of? if so can it only be fixed with an IR filter?

sorry i tried searching but could not find more info on IR

 

[Thomas Wright]

Somehow I don't think you searched too hard fella, there're some great threads on this site about it, but here's a link to an interesting story:

http://www.qgdaluz.com.br/filtros e acessórios-cameras/THE TIFFEN ND IR HOT MIRROR STORY (2).doc

 

[Jason Joseph]

this forum needs its own workflow solution

 

[Andrew Rieger]

To clarify, the IR issue only shows up with heavy ND filters correct? Anything heavier than ND9 will need these specialty filters?

 

[Rob Castiglione]

Hi Andrew,

That is essentially correct but you can see the effects even at .9. Ryan Walters has an Illuminating test (ha ha) on his website showing a side by side comparison between IR sensitivity of the old and new sensors.

 

[Adrian Hernandez]

IRND.9 + ND.3 gave me magenta blacks..

IRND.9 + ND.3 gave me magenta blacks..

How do the IRND.xx filters work?
Today I shoot something with the following filters (farthest to nearest sensor):
- IRND9
- ND3
- POLA

The IRND9 filter blocks all of the IR infection that could affect the sensor?