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sadia
21-07-2009, 03:38 PM
Hello,

Since the weather is poor in melbourne, I am spending most of my weekend time reading on diffrent narrowband filters.

I was reading through Astronomik CCD filter specifications where it says their CCD narrowband filters will also block IR.

If I get a astronomik ccd filter say OIII 6nm do i need to replace my QHY8's default IR filter with a clear filter? or can i leave the default IR filter?


Thanks in advance.

Regards
Sad

Gama
21-07-2009, 04:06 PM
No, you can leave it on. The QHY-8 normally comes with a IR block, although you can also order a "Clear" filter too. The clear is mainly used for IR work, as the Sony sensor is very sensitive to IR.

The IR block is used on color to keep the color balance correct, as IR light effects exposures.
Mono cameras normally have a "Clear" IR pass filter, and thus you need a narrow band filter or whatever filter you place in, to have a IR block. Or you risk exposing the Narrow band light you want mixed with IR light.

In your case, its no problem, as you already have a IR block, so having another has very little effect.

Theo