Where to place the filter?

[hefyjefy]

So just splashed out on an LP filter, placing this for deep sky extended targets nebulae etc. is obvious, there's only one place it can go!  But the scope is 480mm f6 so for things like M57 and other planetary nebulae I have been using a Barlow lens, in that case should the filter go between the camera and the the Barlow or between the Barlow and the object lens?  Does it matter?  In either case it will shift the Barlow either back or forward by about 1/4" which will affect the image scale.

Thoughts?

Geoff

[Demonperformer]

When I use a barlow, I have to add the nosepiece to the camera. I then add any filter at the end of the nosepiece, inside the barlow tube.

[Merlin66]

I use the Baader x2.5 Hyperion Barlow, it has a 1.25” nosepiece and a T thread connection. Works well.

 

[x6gas]

On 11/06/2020 at 02:46, hefyjefy said:

So just splashed out on an LP filter, placing this for deep sky extended targets nebulae etc. is obvious, there's only one place it can go!  But the scope is 480mm f6 so for things like M57 and other planetary nebulae I have been using a Barlow lens, in that case should the filter go between the camera and the the Barlow or between the Barlow and the object lens?  Does it matter?  In either case it will shift the Barlow either back or forward by about 1/4" which will affect the image scale.

Thoughts?

Geoff

I think it's best to place the filter as close to the camera sensor as possible.

[hefyjefy]

On 13/06/2020 at 00:23, x6gas said:

I think it's best to place the filter as close to the camera sensor as possible.

Yes, thinking about it that makes sense, thanks!