!!!FULL VIEW PLEASE!!!
This picture is a mosaic of 18 separate exposures stitched together. The exposures were taken in the primefocus of a 25" Ritchey-Chretien telescope with an opening of 63cm and a F-Ratio of 1:8.7 . Taking in account the crop factor of 1.6 for the chip it was an effective focal length of about 8.5m ! See here
[link] for a picture of the telescope.
The pictures were taken with a Canon D20. We used the M Mode with an exposure time of 1/60 sec at 100 ISO for all exposures. Of course using 200 ISO and a shorter exposure could have resulted in a more sharper image, but the air turbulences (seeing) that night limited the resolution any way.
The stitcher software I use utilizes the Smartblend algorithm to compensate for "moved objects" and lighting differences. That definitely gives an edge above assembling the thing by hand in Photoshop.
The full size original picture is 8100*8100 pixel. (323MB Tif file), so I had to shrink it quite a bit for dA.
Again the credit for this picture is not mine alone, but belongs to our group "Amos Observatory"
If you like what you see, why not visit us at "amos.observatory.at"
[link]
`anmari has been spreading her infectious positivity throughout our community for over 6 years. Throughout this time Ana has been at the core of all things devious, passionately developing an eclectic gallery, helping organise devmeets, participating in chat events and also recently completed dedicating her time as a Community Volunteer. We are absolutely delighted to bestow the Deviousness Award for May 2013 to `anmari, congratulations! Read More
Sta.sh
![[link]](http://www.planetarium-klagenfurt.at/images/stories/Gerlitze/teleskop1.jpg){kind=link}
Not nearly this clear and a LOT fewer pixels to work with.
The problem with the RC or maybe the Canon D20 is that there is a refraction somewhere.
When checking the images for the mosaic I realized that the three color channels were shifted to reference to each other. The red channel was some pix "above" the green channel, and the blue channel was some pix "below" the green. I don't have a clue how that happend since the RC is a mirror telescope!
How ever after shifting the R&B color channels by hand to match the green, the color seam was gone and sharpnes improved a lot!