ever since i took this image of the horsehead, i have been convinced that the QHY9 is a very capable camera. so I am surprised at how close the Astro 40D gets in this test, but I can only let the results speak for themselves.
You're absolutely correct about the QHY9's performance on the HH shot - there's some detail resolved in there I haven't picked up on before!
Back to topic - the Cooled 40D v's QHY9 results.
The resolution from the QHY9 has the edge obviously, but the 40D is capable of 18deg below ambient and it gets pretty cold in the Adelaide Hills of a winter's evening! It was 7degs last week - so there's a possible -11degs where noise would be tamed further.A considerable improvement on 0degs I'm sure.
Thanks for the efforts Phil - there's no denying the power of that QHY9 though...very nice.
Doug
Yes I have to agree with Robin, My 9 was easily reaching -20 C when it was close to 30 C outside this summer. Good comparison though as some of the modded DSLR's seem to work but as your results show the cooled CCD gives just that bit more and this is what people pay for.
Would the QHY9 OSC camera show the same increase in resolution over the 40D? Or is this down to the sensitivity of the Mono CCD?
I'm sold on the simplicity of the cooled 40D, but that increase in resolution is hard to ignore with the QHY9.
What worries me is the stuff Phil talked about - tilt of the sensor v's the type of lenses I use and availability of adapters to fit those lenses (Canon EF mount) Phil: "The M54 thread on the QHY filter wheel is not that common.. I certainly could not find an adaptor to do the job and had to get one custom made (as well as reducing the thickness of the camera-filter wheel connector)."
Doesn't sound very "plug 'n play"!!
Anyone out there doing widefield lens based imaging with mono or colour QHY9 CCDs!!??
Or have I identified a gap in the market?
Doug
Would the QHY9 OSC camera show the same increase in resolution over the 40D? Or is this down to the sensitivity of the Mono CCD?
Phil: "The M54 thread on the QHY filter wheel is not that common.. I certainly could not find an adaptor to do the job and had to get one custom made (as well as reducing the thickness of the camera-filter wheel connector)."
Doesn't sound very "plug 'n play"!!
Anyone out there doing widefield lens based imaging with mono or colour QHY9 CCDs!!??
Or have I identified a gap in the market?
Doug
Doug I would imagine the OSC QHY9 would also do better simply because it's a 16 bit CCD Vs a 12 - 14bit CMOS. It just has greater dynamic range which the DSLR cannot touch in its current form. I think you will have to wait a while to find any OSC QHY9's in peoples hands as they have just been released or are about to be in any case.
Baader have a number of M54 adaptors to suit the QHY9 (mostly M54 -T2, I know as I have them all).
Doug, for god sake don't buy a QHY9 OSC, get the qhy8. Bigger pixels, bigger well depth sony sensor instead of this noisey kodak crap. It also has a bigger FOV than the qhy9 cos of the bigger pixels. I'm sorry I sold mine and I was about to get another when I bought something else way more expensive Only go qhy9 if you want mono.
As for adapters, I get them made when I need them, there's one coming now to connect the qhy wheel (M54) to the tak reducer (M72). It won't take a LP filter, I'll have NB filters in the wheel Should cost about $80 delivered. I send em a drawing (attached) and I get an adapter ...
Doug, for god sake don't buy a QHY9 OSC, get the qhy8. Bigger pixels, bigger well depth sony sensor instead of this noisey kodak crap. It also has a bigger FOV than the qhy9 cos of the bigger pixels. I'm sorry I sold mine and I was about to get another when I bought something else way more expensive Only go qhy9 if you want mono.
As for adapters, I get them made when I need them, there's one coming now to connect the qhy wheel (M54) to the tak reducer (M72). It won't take a LP filter, I'll have NB filters in the wheel Should cost about $80 delivered. I send em a drawing (attached) and I get an adapter ...
Who are you using for your adaptors? That sounds like good value..
Would the QHY9 OSC camera show the same increase in resolution over the 40D? Or is this down to the sensitivity of the Mono CCD?
I'm sold on the simplicity of the cooled 40D, but that increase in resolution is hard to ignore with the QHY9.
What worries me is the stuff Phil talked about - tilt of the sensor v's the type of lenses I use and availability of adapters to fit those lenses (Canon EF mount) Phil: "The M54 thread on the QHY filter wheel is not that common.. I certainly could not find an adaptor to do the job and had to get one custom made (as well as reducing the thickness of the camera-filter wheel connector)."
Doesn't sound very "plug 'n play"!!
Anyone out there doing widefield lens based imaging with mono or colour QHY9 CCDs!!??
Or have I identified a gap in the market?
Doug
Doug I would imagine the OSC QHY9 would also do better simply because it's a 16 bit CCD Vs a 12 - 14bit CMOS. It just has greater dynamic range which the DSLR cannot touch in its current form.
Mark
On the topic of bit depth/dynamic range folks may be interested in this article from Craig Stark:
CCDs beat DSLRs as they have lower noise and greater sensitivity and therefore much better signal to noise ratio. Whether you digitise the result with 14bit or 16bit precision is not so important, as I understand it.
Doug, for god sake don't buy a QHY9 OSC, get the qhy8. Bigger pixels, bigger well depth sony sensor instead of this noisey kodak crap.
LOL Robin!!!
Wisdom around the forum(s) is that the Kodak chip would be better for widefield work (@300mm FL) than the Sony due to the smaller 5.4 micron pixel size of the Kodak sensor - but trade off being the Kodak needs to be heavily cooled.
The QHY8 Pro looks a nice camera from specs.
I'm still a bit surprised there's no off the shelf adapters available for these cameras given their purpose and the market they're intended for!?
CCDs beat DSLRs as they have lower noise and greater sensitivity and therefore much better signal to noise ratio. Whether you digitise the result with 14bit or 16bit precision is not so important, as I understand it.
Cooled DSLR (@ -18 degrees) is still in the running then Phil!
I'm still a bit surprised there's no off the shelf adapters available for these cameras given their purpose and the market they're intended for!?
Hi Doug,
I think your confusing the Filter Wheel adapters and the QHY-9(C).
The Filter Wheel has the M54 threads, but as pointed out, it has a reducer/adapter which reduces this to "T" thread and a nose, which is the norm for cameras with ccd's of this size (Foot print/area).
This size thread (M54) was selected so as to accomodate larger size CCD's, and not limit the use to only small cameras.
The QHY-9(C), also has "T" thread as standard, and does not have M54 threads.
On Pixel size, both you guys are correct, the 8300's smaller size does provide better resolution, and the Sony chip has its benifits. Any KAF 8300 will do its job, and its just a matter of your local atomspheric conditions, equipment in hand and future needs that will make your final decision as to which way you turn.
QHY9 is approx $3000AU.(perhaps Theo or others could confirm)
To cool my (user supplied) 40D at Central DS: $1230AU - that includes a UV/IR fliter change too if you haven't had it done already. http://www.centralds.net/en/index.htm
Doug
QHY9 is approx $3000AU.(perhaps Theo or others could confirm)
To cool my (user supplied) 40D at Central DS: $1230AU - that includes a UV/IR fliter change too if you haven't had it done already. http://www.centralds.net/en/index.htm
Doug
Doug if you are going to compare camera's you had better include the new cost of a 40D + your mods. QHY does not just sell a peltier. A quick search on the net lists them at about $1500 so your total cost is about $2730. So the real question..... is the QHY9 $270 better then the worked 40D ??????
Doug if you are going to compare camera's you had better include the new cost of a 40D + your mods. QHY does not just sell a peltier. A quick search on the net lists them at about $1500 so your total cost is about $2730. So the real question..... is the QHY9 $270 better then the worked 40D ??????
But, for me today the price of my 40D isn't in the equation - it's bought, done and dusted...in the past!!
Realistically, I would have to sell my 40D + accessories/filters and come up with another $2K to buy a QHY9 (minus NB filters and adapters and gawd knows what else!!!)
...or come up with approx $1K for the cooling mod!
i bought my 40d for $650 2nd hand - took 5 photos and then shipped it the same day to CentralDS. Live view focusing and using the canon lenses is the winner for me.
Should cost about $80 delivered. I send em a drawing (attached) and I get an adapter ...
