Filter position

[GrantEb]

Hi all

I have just purchased a HA filter, but it is the 1.25" version.

I am imaging with a 1000d , SW Coma corrector and 150PDS.

I know the 1.25" filter is not ideal, but got it at a good price, and I am keen to try out some HA imaging. What would be the best position of the filter with the above, to minimise loss of image on the chip?

I have tried to find diagrams on the forum of the light path in a newt through a CC to dslr, but with no luck yet.

EDIT: From what I can think, should it go as close to the chip as possible?

Thanks

[ollypenrice]

Yes, I guess as close as possible but I think you might struggle.

Olly

[GrantEb]

Thanks Olly. Should be easier than mounting a 400p on a NEQ6 though, lol.

[Shibby]

You might be best off dropping the coma corrector to play with your ha imaging - you'll find it easier to get the filter in I think. I say this because using a 1.25" you'll get quite prominent vignetting towards the edges of the sensor anyway.