Posts Made By: Kevin Brennan

wow, quite a bit of detail for such a tiny disc!

Kevin

Fantastic image!

Kevin

Not sure how far that will get you. I am sure most any you get here on astromart from a reputable seller will check out okay.

What you really need won't really get done by a dealer. That is a real careful cooling and collimation first, then a critical star test to insure you are getting one of the better ones.

I know that this will probably get me some flames, but I have bought numerous SCTs, and have become extremely familiar with critical collimation at high mag on steady nights, cooling and star testing. After doing all this with several, I found only a couple to be truly quarter wave or better. Many of them were okay to mediocre. But they are also very reasonably priced.

The key thing a dealer probably would be able to check out for you quickly, is mirror slop, and focus shift. They could check out collimation, but it will need to be recollimated by you after shipping. Especially the bigger ones. You may want to use one of the smaller dealers, especially imaging ones. They don't necessarily need to be a celestron dealer as they may not even know as much as you think. When I first started, many years ago, The big C dealer I used told me at f10, you didn't even need to worry about collimation. That could not be further from the truth. Tells me, they were ignorant on the subject or unscrupulous.


Regards,
Kevin

Yea, tell me about it....

Well, at least I got out last night for the first time in several weeks.

I think we got 6 inches or so of rain here recently.

Kevin

Really cool image Dietmar. I can't recall seeing a deeper M27.

Kevin

Pretty impressive Anjal.

clear skies,

Very nice shot Ivan. I have been rained out almost all summer here in NE. argggh. Least I can see great shots like this to keep me going.

clear skies,
Kevin

Great shot Peter!

Kevin

Yes they can on occasion. I had one out of many. Yes, they were all critically collimated and cooled. They can also be "great" compared to decent samples of other designs.

The think I sometimes chuckle about is when every one for sale says "great optics" or occasionally you will see a whole slew of them that are "hand picked". Yes, somebody pics them up with their hand, when they put them in the shipping box. LOL

Kevin

Mighty fine image Jim. I take it you used a 48mm or similar Ha filter perhaps in the photo adapter or is this something that goes in the body in front of the ccd?

Kevin