LRGB with CCD and Camera lens

[Astroblagger]

Hello, im just getting my rig togeather for using my Atik 314L+ with my canon 200mm F2.8 lens, i see many lovely narrowband images taken with this set up, im just wandering what image i might expect from normal LRGB filters using this set up? Anyone tried?

[ollypenrice]

You need to be ultra, ultra careful with focus. I found this from Telescope Service was a great help.

http://ollypenrice.smugmug.com/Other/Takahashi-EM200TEC140/i-4TCd6Px/0/L/IMG_1193-L.jpg

I used the larger format Atik 4000 with this lens and enjoyed it. This is a 2 panel mosaic and included an Ha Layer as well as LRGB but it gives you an idea;

In a one shot colour Atik 4000 I got this;

I used a home made front aperture mask to lose the diff spikes when stopped down with the diaphragm.

...but with the small chip you might run wide open quite easily. Bliss!

Olly

[Davey-T]

I've got all the bits to try this but haven't got round to it yet, I think it's worth getting an HA filter if you can afford one.

Dave

[Astroblagger]

Stunning images as per usual olly, I've got the micro focuser rings filters etc and TS filter drawer I'm just shortening a dual mount bar to fit my finder guider at the moment and clamp for the lens no use using a giant dual mount bar for such a light set up, interested in the mask though. How did you make it?

[ollypenrice]

I calculated the diameter needed to get F4 (and other focal ratios) at 200mm, so F4 would be 50mm. I first cut the outside diameter to fit in the hood then the inside with the compass cutter. I sprayed these discs black and held them in the hood with the sticky draft excluder tape. Steve Richards has tried this as well.

Olly