first (half decent) light with QHY9

[Phil Hart]

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 (http://philhart.com/gallery/Astrophotography/Nebulae/HorseHeadHA_resize.jpg.html)

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.

[AlexN]

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..

Well done mate... well done.

[allan gould]

Have to agree, a really lovely shot. I love the colour and detail as it's not overprocessed

[Octane]

I'm going to go against the grain here. The image from the 20D looks far superior (natural) to me.

Regards,
Humayun

[zipdrive]

the colour tone works for me, nice! thanks for sharing.

[Davros]

I like the detail from the DSLR but i love the subtle colour of the QHY9

[Hagar]

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.

[mill]

Phil that image looks excellent with nice colors and loads of detail :thumbsup:
Do you have an higher res pic of this somewhere?

[dugnsuz]

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

[Phil Hart]

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..

http://www.mpas.asn.au/Astro/Tips/cool_or_not.htm

[AlexN]

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 (http://www.robgendlerastropics.com/HARGB.html)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.

[dpastern]

I prefer the QHY9 image - both in terms of grain and colour. I find the 20D image to be too gaudy for my personal liking.

Dave

[dugnsuz]

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

[Phil Hart]

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.. :-)

[David Fitz-Henr]

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.

[telecasterguru]

Phil,

Most interesting comparison.

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.

Frank

[Jen]

Beautiful pics Phil :thumbsup::thumbsup::thumbsup:

[Moon]

Phil
As others have said, this is a very interesting comparison - thanks for posting.

I really like the extra detail and smoothness in the QHY9 image - I think this is why it looks so great.

Any idea why there are more stars in the 20D image? Could it be the slightly larger pixel size or is it the processing?

James

[CometGuy]

Hi Phil,

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.

Terry

[multiweb]

What an awesome shot. Smooth and great details at the same time. Top work on your first light! :eyepop: :thumbsup:

[Phil Hart]

The QHY9 image is largely h-alpha which really cuts down the relative brightness of the stars - while most of the nebula comes through in full strength, only a tiny percentage of the broadband starlight is captured. I used some broadband luminance in the image composition, but only in bright areas.. so that has added back in the bright stars but not the faint ones. The 20D image is seeing the full spectrum for each star over the full four hours.

[Phil Hart]

Yes.. I was getting fogging on the sensor window on my first attempts so took it to Theo who installed the heater element very easily. No issues now..