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Whats better for long exposures with lower noise? a dedicated CCD astro imager, or an IR modded, peltier cooled DSLR?
generally a dedicated CCD is less noisy... note some ccd chips are noisier than others. you will find however to get a 10 megapixel chip is much dearer on a CCD ( the QHY8 is 6 megapixels and as noise free as ive ever seen)
Also, can anyone gimme a guestimate as to comparative exposure times/noise leves between a DSLR and an average CCD? would a 10 mins CCD exposure have the same noise as an average 3 mins DSLR exposure?
it depends on the well depth of the pixels at first glance ie, a 20 min exposure on a qhy8 will leave some color still in stars less than mag 8 this wont happen on a 20 min dslr exposure they will be burnt out.
when i get a 10 min exposure its pretty dark but you can stretch it out to reveal all the detail. it would take pages to describe all the ins and outs........
there are a whole bunch of variants to consider , well depth, bit depth, noise of individual chips. Note i think the cannon 40d is a pretty good buy lots of megapixels, pretty good for dslr, if its modded then Ha is good. One further point having used both, the temp makes a HUGE difference, try shooting a cooled CCD and a DSLR on a warm night (25 deg) and the dslr is a poor second.
i had the money to buy a 40d or a QHY8 , i bought the QHY8 and would do so again in heartbeat, note i already have a camera for regular pic taking so that wasnt an issue, its astro only.
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