alternative reducers SCT

[blink138]

hello members i am doing some homework on flatteners and reducers for a normally aspirated c11
i have the normal celestron f6.3 at the moment but wondered if there is a better product for imaging and if anybody has got experience in other products i would be very interested in their views
thanks in advance
pat

[blink138]

anybody with any experience other than the 6.3?
pat

[Terry B]

Sorry. I have the Meade version and it works well on my C11. No experience with anything else.

[blink138]

thanks terry
does your meade(6.3?) have unacceptable vignetting?
pat

[Jbunky86]

Hi Pat
Jason here, how's the ed80 cf going ?
I hope your brother is enjoying it.

Have you considered utilizing fastar on your c11?
It's suppose to be awsome for imaging. I believe the required fastar attachment corrects for all unwanted optical aberrations.

Cheers Jason

[wasyoungonce]

Alan Gee tele-compressor (http://www.alpineastro.com/optical_accessories/alan_gee/alan_gee.htm).

Kinda an early edge optics reducer in that it fits inside the threaded primary baffle tube. Although I think they were for C8's and 9's not C11's (different baffle dia).
:shrug:

I think they reduce to around F5.9....here (http://www.steves-astro.com/?m=200906) is a gent using this on a C11.

[blink138]

heh hi jason yes he is as happy as a dog with two willys, it makes me a bit jealous...... if only the weather would improve we will get a chance to put it through its paces!
as far as the f2 is concerened that is the precise reason i bought my CF c11 as it was already hyperstar ready
however i feel that i am no where skilled enough and it seems a bit scary at the moment
pat

[blink138]

hello brendan thanks for your reply
now that looks very interesting! the link, upon reading it, gave me the impression it was quite old as almost as an afterthought says that for visual it could be used for those "new fangled" aftermarket focussers
i have been reading about the starizona f7.5, but cant really find enough users of the product
pat

[blink138]

by the way brendan it does mention about being used in a c11
pot

[Terry B]

I use mine with my spectrograph so don't really know about vignetting. I did connect my ST10XME and there was certainly know vignetting with the size sensor in the camera. Bigger CCDs would prpbably have a problem though.

[rogerg]

I have used the Meade 6.3 for years but am currently waiting on a Asto Physics CCDT67, hoping it will suit my ST8's larger FOV. This is for a 12" Meade.

[blink138]

thanks guys
perhaps the sensor is just too big on a dslr to avoid vignetting with ANY sort of reducer...... i would certainly like to try a different one to see if it is any better than the ubiquitous celestron f6.3
the starizona f7.5 is $350!
pat

[blink138]

roger how will the AP be better than the celestron as they "reduce" almost the same amount
will the optics be better and give a flatter view?
pat

[Terry B]

Any reducer will reduce the size of the image circle. It won't make much difference what brand. I don't know the size of the standard C11 image circle. Maybe this info is on their website. This will tell you the maximum size sensor that can be used theoretically. If this is smaller than your sensor then there is no point experimenting with reducers.

[blink138]

ha ha! of course terry that makes complete sense!
pat