From: Milton Aupperle <milton@outcastsoft.com>

Date: May 7, 2011 10:12:34 AM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Info

It depends on the CCD (size of the pixels and whether it's a HAD or EXHAD), Filters (if it monochrome), Aperture of the scope and Focal length. So you'll have to experiment.

To give you an idea of exposures, here is what I have used in the past. My skies generally suck for doing long (> 3 meter) focal length work, except in very rare occasions.

For a MAK 127 mm aperture scope at 3,000 mm focal lengths using a Flea Color camera (HAD CCD of 7.4 micron pixels), I was shooting at 7.5 fps and 133 ms exposure.

http://www.outcastsoft.com/AstroImages/Saturn_MJA_20060411.jpg

For C8 200 mm aperture scope at 6,100 mm focal lengths using a Flea Color camera (HAD CCD of 7.4 micron pixels), I was shooting at 15 fps and 67 ms exposures.

http://www.outcastsoft.com/AstroImages/Saturn20070412.jpg

For C8 200 mm aperture scope at 5,000 mm focal lengths using a Grasshopper Monochrome camera (ExHAD CCD of 6.7 micron pixels with AstroDon "E" series LRGB filters), I was shooting at 15 fps and 67 ms exposures.

http://www.outcastsoft.com/AstroImages/Saturn20090502MJA.jpg

There are other examples on my web site:

http://www.outcastsoft.com/AstroImages/AstroIndex.html

and I always list the focal length , aperture and exposure setting / frame rate I used in my images.

HTH..

Milton Aupperle

On 7-May-11, at 3:49 AM, Davide Urbinati wrote:

hi...

witch settings i must use for photograph Saturn with point grey grassoppher?!

Thanks

Davide