What camera for EdgeHD 800 Fastar?

[jackd]

I already have a CGEM and plan on purchasing a EdgeHD 800 this week. Which camera should I be looking at to use the Fastar setup? Any suggestions? 

I am on a limited budget of $1300.

Would a Celestron Nightscape 8300 be a good match?

[jackd]

Or would this be a good choice?

http://www.adorama.com/QHY8L.html?gclid=Cj0KEQjwtO2wBRCu0d2dkvjVi5cBEiQAMEIVGaLCGjqrb9QGKErvva_o-kGYXIsVJgmdA8oQvsF8Z-MaAlQA8P8HAQ

[Freddie]

Assuming as you are planning to use fastar, you want to image DSOs, are you sure that is the best scope for the job?

[jackd]

My friend has one and gets what I consider great shots. But I am fairly new to all this. What would you suggest Freddie?

[ollypenrice]

Ultra-fast optics are ultra-challenging because the depth of field is incredibly shallow so focus is even more critical than usual. Any tilt on the chip means one side is in focus while the other isn't. Collimation is also critical.  There is no faster system than the Hyperstar but there are easier and more tolerant systems.

The cooling of the Nightscape 8300 is only to Delta 20 I believe. In long hot Missouri summers this would be totally inadequate. The 8300 chip needs, like any Kodak chip, to run very cold.

With the frontal location of the camera you would need a filter slide drawer in order to use a mono camera. You might, therefore, prefer One Shot Colour. This has disadvantages and is rather slower than mono but this wouldn't be a problem at Hyperstar speeds. You should also choose a camera which will fit behind the central obstruction or it will produce diffraction artefacts. Atik make a range of slim bodied CCDs with this in mind.

Olly

[Freddie]

As Olly has said the fastar isn't the easiest so as you say you are new to this you may want to have a look at some other scopes that may be better for your needs and experience. You will also need to decide if you want DSO or planetary. I assume DSO from what you have said so far. Once you have decided on the scope, you can then think about a cam to best match that scope.

[pete_l]

It's also worth noting that although some LRGB filters claim to be parfocal (I.e. the focus does not change as you swap from one colour filter to another) that ain't necessarily so. And as the focal ratio gets smaller, and focusing becomes more critical, what errors there are in the filter set's par-focality will become more apparent. So filters that don't need the telescope's focus tweaking at F/10 could well need an adjustment at F/2.

I'd suggest, therefore, that at F/2 you wouldn't want to be swapping filters too often, so an OSC camera would be a better choice than a set of LRGB filters.

[steppenwolf]

Also bear in mind that if you are ONLY intending to ever use the Edge HD 800 in 'Fastar' mode, you will not benefit from the Edge optics as these are housed in the baffle tube which is only used in 'Cassegrain' mode.

[Waldemar]

Don't forget that the corrected image circle of a HyperStar is only 25 mm. APSc is the absolute maximum sensor size for the HyperStar (Fastar)

Any camera with the Kodak 8300 would do, but cooling maybe an issue, especially because the CCD is in front of the lens and shielded by the dew cap, hence little natural cooling.

A deltaT of at least -40 could be essential to get good results. I had a C-11 with HyperStar with a QHY8Pro (OSC) camera (better cooling then the L version) but never got rid of spherical aberration. After getting frustrated and selling the whole set-up I realised collimation and positioning of the HyperStar in the corrector plate could have been the main cause...

There are not so many camera's suited for the HyperStar because of the size and cooling. ATIK and QHY offer very nice solutions. 

In light polluted areas mono camera's should be preferred, because of the better pixel use and therefor higher definition (No Bayer matrix) and the narrow band filtering possibilities.

Smaller pixels give better results in fast sytems (cam vs arcsec/pixel formula: pixelsize/focal length X 206.3 = arcs./pix). The ATIK 4120 EX would do great @ 1.18 arcs./pix, but it is only available in OSC at the time. I realize this is beyond budget, but maybe saving and gathering information and thinking it over in the mean time offers a solution for that ...

Besides... a mono camera with the necessary LRGB or NB filters will be quite an investment as well...

my 2c.

Waldemar

[Waldemar]

You may want to read this too Jack: http://stargazerslounge.com/topic/52031-choosing-a-ccd-camera/

Very informative writing, a 'must read' !!

Waldemar

[fielderda]

I'm thinking about graduating from a DSLR and 0.7x reducer with my EDGE HD 800.

Any thoughts about ZWO ASI1600 Cooled with Faststar/Hyperstar?

My second question:  Mono of OSC? I'm concerned that the filter wheel with a Mono will block too much light with the Hyperstar?

I typically do DSO's but would like to do the odd planetary imaging.

 

Thanks for any suggestions from the newbie!