ASI120MC-S UV IR?

[WilliamAstro]

I was planning on getting a UV/IR or Luminance filter for planetary imaging and I realise that my sensor already has a UV/IR protection window on it, Does this mean I can record UV, IR and L data with the protection window?

[Cornelius Varley]

The UV/IR filter on the camera is a blocking filter to stop uv/ir light reaching the sensor. Camera sensors are sensitive to these wavelengths, without the filter the image would have a pink cast to it.  Luminance data is recorded using an ir pass filter which blocks all other wavelengths, the opposite of the filter on your camera.

[WilliamAstro]

Is there one for sale? (IR/Luminance filter) (on websites)

Edited May 8, 2020 by WilliamAstro

[Cornelius Varley]

The camera has a built-in ir blocking filter. Adding an ir pass filter will then result in no light reaching the camera.

[WilliamAstro]

1 minute ago, Cornelius Varley said:

The camera has a built-in ir blocking filter. Adding an ir pass filter will then result in no light reaching the camera.

But can I still record Luminance on there?

Edited May 8, 2020 by WilliamAstro

[Cornelius Varley]

16 minutes ago, WilliamAstro said:

But can I still record Luminance on there?

No, because L data is a level of brightness in mono data using an ir pass filter. The built-in ir blocking filter and an ir pass filter would effectively stop all light reaching the sensor. Your camera recordes colour images, RGB(L) imaging is done using mono camera that record the full spectrum using separate filters.

[symmetal]

The UV/IR cut sensor window is the same as a Luminance Filter so you don't need an extra luminance filter. It will block UV and IR wavelengths which is what you need to record one-shot RGB images on your colour camera.

Alan

Edited May 8, 2020 by symmetal

[WilliamAstro]

Ok thank you for the advice!

[symmetal]

2 minutes ago, Cornelius Varley said:

No, because L data is a level of brightness in mono data using an ir pass filter.

I think that's confusing WilliamAstro. Normally, on a mono camera L is recorded using an IR and UV cut filter which his camera already has. Being a OSC camera he is effectively recording the luminance wavelengths split into RG and B by the camera bayer matrix. An IR pass filter records only IR wavelengths and can be used as a substitute for luminance for mono planerary imaging as it is less affected by seeing. The built-in UV-IR cut filter on his OSC cameras doesn't allow IR only recording.

Alan