I purchased a used QHY8-Pro off a user here last week and got the chance to give it a whirl last night. Conditions in Melbourne were actually pretty good (considering that I'm in a bortle 8 zone).
It took about 2-3 hours before I got an actual image on the screen in APT. It was a mixture of finding the right focus (which was way different to the DSLR I was previously using), fighting with the temperamental and rather poor drivers for this old camera, and finding the right gain/offset. Once I did get some light though it was instantly clear that I could collect a lot more data with this camera than I ever could with the DSLR. The combination of being able to pick up some Ha and the built in cooling made a huge difference.
I'm not entirely happy with this result, obviously there's some pretty horrendous gradient around the edges. I'm not entirely sure what that's from, but since it's not appearing in my raw shots I'm betting it's a result of a wrong setting in Pixinsight. Furthermore the core is blown out, which I know I could correct by capturing some shorter exposures and blending those in - something for a future date once I'm more comfortable with this new setup. Speaking of Pixinsight though, it is incredibly powerful but also incredibly confusing - I'm currently following the workflow outlined in Warren Keller's Inside Pixinsight. There are a mind-boggling number of parameters that can be changed, the learning curve is steep.
Still, I've got to say I'm pretty impressed with what I got considering it was my first night out with this camera and first real processing attempt in Pixinsight. If anyone thinks they might know what the lightened edges are from please let me know and critique is welcomed as always!
Gear Used:
Explore Scientific ED102 FCD100 CF
QHY8-Pro OSC
Skywatcher 50ED Guidescope w/ ASI 290mm Mini Guidecam
Skywatcher EQ6-R Pro Mount
Captured with Astrophotography Tool
Guiding and Dithering done with PHD2
Processed in Pixinsight using:
60x60s Lights
60 Dark
60 Flat
60 Bias
David
That’s an excellent image of M42 considering it’s the first time using a new camera
Well done !
As your aware terrible bushfires with loss of life and property have plagued our state including the perimeters of the Sydney basin so air quality is very poor, astro imaging is on hold until conditions improve
You should be very happy with that result David. No doubt you'll sort out the gradient problem, I think it's probably something which occurred in your processing as you stretch the data to gain as much detail from the low contrast subs. Shooting in light polluted skies requires a different set of processing techniques to combat the severe sky glow. I think you've still done a good job and considering the unfavourable location to shoot from, looks like you've established the camera works well and will produce great shots from a dark site. Maybe try a LP filter of some kind if you continue to shoot from Melbourne. Well done!
Excellent first effort David. You've done well with the core. Most first timers over expose that region but you've kept it in check as well as being able to pick up some of the fainter stuff under bortle 8 skies. To answer your query regarding the white edges I'm not exactly sure if this is the cause but it reminds me of dreamer's haze (a.k.a light leaks) similar to what you'd get on film back in the day so maybe check around your camera/filter for any light leaks. Another thing to check is if your flats are calibrating correctly because if they're not then they too can introduce some unusual gradients. Good news is that it's fairly easy to correct so your data is fine. Congrats on the new camera.
I'm going to have another look at processing all the data and see if I can eliminate that gradient, it might be that I've taken my flat incorrectly or processed them wrong. Cheers again!
