some folks may be interested in these early results from my new (secondhand) QHY9 CCD. still got a lot to learn about the world of CCD image capture and processing but starting to get some decent results.
the main image is about seven hours of h-alpha and forty mins each R/G/B and Luminance. Black and white h-alpha version here
for interest, i've also attached a quick and nasty crop comparison with a Hutech 20D version taken in 2007. the images are totally different.. QHY9 on the left is 8 hours total, mainly h-alpha (more fine detail) while the 20D is about 4 hours broadband colour. QHY9 image has not been processed for such rich colour, but the inherent noise of an uncooled DSLR is still quite striking compared to the smooth tones of the QHY9 CCD.
Stunning result Phil!! The comparison between the Hutech 20D and the QHY9 tells the story well doesn't it... Granted, the CCD image has much more exposure, but the image is fantastic none the less. you should be very happy indeed! I really like your subtle colour..
Very nice Phil. Glad to see you have it all up and running. I tend to like the colour of your old image but blending Ha can be a real pain that I never quike got the hang of without either nice pastel colours or gaudy colours which were a bit of a put off. The noise level is definitely noticeable though.
Keep at it.
The smoothness and lack of noise in the CCD image is marked and striking in comparison with your DSLR image.
I've been tossing around the idea of a cooling mod for my 40D (Central DS) for a few weeks now for this very reason! It would be sweet to capture 8 hours worth of iso1600 subs with minimal noise!
Doug
Having seen Steve Mohr's cooled 40D from Mornington Peninsula I have to admit the cooled DSLRs are very attractive.. and very simple to image with. His test dark frames are much more convincing than even those on the CentralDS website..
With blending Ha and RGB data, As Doug said, it can be really difficult to get rich colours, its either too saturated, or too pastel most of the time..
I was poking around on the net looking for tutorials on the best ways to do it, and found THIS on Rob Gendlers site... If you blend your ha 60~80% into your red channel, and then construct your RGB image as normal, you'll find that the colours come out a hell of a lot nicer. You'll get the rich colours you're used to getting with RGB data or OSC data whilst maintaining the extension and detail given by the Ha data...
Its a really good read, very easy to follow and I've found since doing this that my Ha:OSC shots have improved greatly.
Having seen Steve Mohr's cooled 40D from Mornington Peninsula I have to admit the cooled DSLRs are very attractive.. and very simple to image with. His test dark frames are much more convincing than even those on the CentralDS website..
Holy Moly Phil - that's awesome and very interesting!!
Strange that the Central DS 40D has a better thermal signature with the cooling off!!
I'm currently imaging the SMC in Ha, iso1600 at an ambient temp of around 18 degrees C.
The noise is unbearable!! This cooled DSLR route is looking very attractive - pennies will need to be saved I reckon!
Cheers
Doug
Strange that the Central DS 40D has a better thermal signature with the cooling off!!
Doug
It's not that strange when you see it in the field.. it has a huge heat sink sticking out the side of the camera which still conducts heat away from the chip.. the fun just increases the heat exchange with the air for greatly improved performance.
I think it deserves very serious consideration.. :-)
Hello Phil - great image ! Nice and smooth with good detail in the nebula. The DSLR is certainly more noisy, although it does show more stars ? The colour is a result of processing applied, so I certainly wouldn't hold that against the CCD.
The CCD is very smooth but I like the colours of the DSLR. I think both have merit.
Your processing to my eyes is very good. So to my mind the CCD v DSLR argument is still alive and kicking although the cost of the CCDs seems to be moving in the right direction.
Beautiful shot, all the detail around the horse is wonderful. Bet your really enjoying the QHY9. Have you done the heater board mod yet? (its well worth it!)
The biggest difference your seeing here is the greater H-Alpha sensitivity of the QHY9 compared to a DSLR (no amount of cooling is going to help a DSLR here I'm afraid). But I still like the 20D shot very much.
