Hi Avandonk
I still have a lot learn about pushing the processing without it looking too fake i usually back off and have them looking a bit more normal . I agree theres more detail in there .
A normal SN dosn't have a flat field for the same reason a Schmidt Camera needs to have the film bent into a curve.
The only thing the Schmidt plate does is reduce coma by half which for an F4 is still a lot.
A guy in Japan came up with the idea of using a refractor objective infront of the camera , in this case a Borg 50mm F10 ED which helps alot . moving the corrector 400mm up the tube improves thing further still. Let me know if anyone wants his website.
I also replaced the focuser with a CR2 , a great focuser.
I don't have a problem with collimation in the currant set up it was when I extended the tube 400mm and had to use a spider to get the diagonal in the right place the spider wasn't up to holding an 80mm diagonal. Doing this halves the coma giving a well corrected field out to 35mm format.
Thanks for your excellent shot of the rosette , how old is your Canon 300 F2.8 I had thought of buying the new model which is excellent but expensive. Although I had a guest here that uses the 600 mm F4 ( I think he has deep pockets ) with great results.
Thanks everyone for your input and kind words.
Zane
Quote:
Originally Posted by avandonk
Yes good shots but need more work (processing) ,something has been lost the weak nebulosity,surely 60 min total should be better than that.Check out this pic
http://users.bigpond.net.au/avandonk/RosetteN.jpg
Taken in a hurry 3x330sec Canon 300mm F2.8L Hutech Nebula filter ISO 1600.Just before dawn.
Tornado33 is correct as usual, SN cameras have a flat field.There is a lot of FUD (fear uncertainty and doubt) spread about the difficulties of collimation of SN optics.I have no experience with them.
Bert
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