IR filter for webcam

[leelee970]

Opps, I forgot to screw on my IR filter on my webcam last night.

What difference would this make to the final image ?????

Lee

[Cath]

One possibility is if the light was travelling through any glass (lens) then the IR part of the spectrum could well be focused slightly differently, which means the image won't be quite as sharp as it could otherwise be.

Is it a colour webcam or monochrome?

Did you have any other filters inline?

Is it a modified (in any way) webcam?

[leelee970]

I've dug out my old Philips PCVC675 (yep, that old). It's colour.

I usually use my self modded SPC900 (I even replaced the CCD for a larger one) but due to the new pixel size the image scale is smaller.

Therefore I need to use a X3 barlow + extension tube to get anything decent from the SPC - this extra length makes things a little more problimatic.

So I decided to give the old PCVC675 a go and was surprised at the difference in image scale.

[leelee970]

the top one was from last night using the PCVC675 without IR filter + x3 barlow on my Orion Europa 200. Best 1000 frames stacked by AS!2 and wavelettes adjusted by RS6.

the next one was SPC900 with IR filter + x3 barlow + extension tube on same scope and same processing.