Olympic Torch in the Southern Skies

[strongmanmike (Michael)]

Originally Posted by marco

Mike, I am using mine at -30C in Coonabarabra with no problems even in summer time (of course, during the night). Expect at least -55C/-60C from your camera. Noise is almost un-noticeable, you will be very surprised by that!

Marco

OK, that would be a nicer cooling level for my liking too. These big chips in the ProLine architecture have such low read noise that being able to cool lower is deffinitely an advantage. I want a camera that is read noise limited and with such low read noise you need great cooling (preferrably without the need for water) to take advantage of it

Mike

[marco (Marco Lorenzi)]

Originally Posted by strongmanmike

I want a camera that is read noise limited and with such low read noise you need great cooling (preferrably without the need for water) to take advantage of it

Mike

There are several nice analysis on this camera made by Richard Crisp in his website. In reality there is another limiting factor called RBI on this large chips that could limit the exposure. That depends on temperature too. With about -30C and subframes of 10 minutes the camera is indeed limited by the (little) read noise, that's why I am using this standard subexposure as upper limit. Sometime I use lower subframes if *very* bright stars are in the field to recover a little more color information on stars core for the final processing.

If you want to use the camera with longer subexposures than you need to cool much more to have the image read noise limited.

Clear Skies
Marco

[multiweb (Marc)]

Originally Posted by gregbradley

Well here is another version that is more muted and less stretched and far less noise and grain:

http://www.pbase.com/gregbradley/image/122386593

Greg.

now that is superb!

[gregbradley]

Thanks Marc.

Greg.

[jase (Jason)]

Latest version has the goods Greg. Nice work indeed. Hope your permanent obs is coming along well too.

I do laugh at this thread however. Seems like a p***ing contest. Has anyone actually tried the Apogee U16M with D9 cooling? Minus 75 below without water reticulation my friends! Seriously though, what are the gains. One can do accurate work operating at -10 with good darks. Moot point. Lets not get too carried away with equipment shall we. Its what you do with it that counts.

[strongmanmike (Michael)]

Originally Posted by jase

Latest version has the goods Greg. Nice work indeed. Hope your permanent obs is coming along well too.

I do laugh at this thread however. Seems like a p***ing contest. Has anyone actually tried the Apogee U16M with D9 cooling? Minus 75 below without water reticulation my friends! Seriously though, what are the gains. One can do accurate work operating at -10 with good darks. Moot point. Lets not get too carried away with equipment shall we. Its what you do with it that counts.

...seems you are happy to join in the errr? p***ing (?) contest too though Jase

Hmm? wonder why Apogee bothered if -10C is good enough

No point having super cooling if the read noise is high

...how are ya anyway Jase? good to have the Jennings frankness back ...anyway back to Gregs nice image Ooops

[Peter Ward]

Muddy background and cyan casts near the top of the frame. The object of interest is lost in the frame...ie more FL (via a barlow) would have helped quite a bit.

Sure I'm picky, but playing with A-league gear I would have expected better...

Many of the acquisition aspects handled really well....but gotta say, the processing side needs some work...

[Bassnut (Fred)]

Top work Greg, its been a while .

Dont often see the Vela here, nice change.

[gregbradley]

Originally Posted by jase

Latest version has the goods Greg. Nice work indeed. Hope your permanent obs is coming along well too.

Thanks Jase. Yes I hope to start construction soon.

Thats true about the gear, both are super cameras. I was tempted to do the DO9 body with that -75C but it still takes 35 minutes to get there and that's quite a while if you travel and you want dusk darks. If you forget to start up early you miss out on darks. If the power gets interrupted at 1am you wait 40 minutes for it to regain cold temps. So it is quite a minus for an otherwise awesome camera.

I do laugh at this thread however. Seems like a p***ing contest. Has anyone actually tried the Apogee U16M with D9 cooling? Minus 75 below without water reticulation my friends! Seriously though, what are the gains. One can do accurate work operating at -10 with good darks. Moot point. Lets not get too carried away with equipment shall we. Its what you do with it that counts.

Originally Posted by strongmanmike

...seems you are happy to join in the errr? p***ing (?) contest too though Jase

Hmm? wonder why Apogee bothered if -10C is good enough

No point having super cooling if the read noise is high

...how are ya anyway Jase? good to have the Jennings frankness back ...anyway back to Gregs nice image Ooops

Thanks Mike. By the way I think I p...... furthest!!! hehehe.

Greg

Originally Posted by Bassnut

Top work Greg, its been a while .

Dont often see the Vela here, nice change.

Thanks Fred. Yes it has been quite a while. I even have some old M42 narrowband I have still to process from Oct lat year!