Taming the Beast

[carlstronomy (Carl)]

Well after many years of DSLR imaging I took the leap of faith and purchased a ZWO ASI294MC PRO. (Purchased here on the forum - Thanks Paul and Ross)

After a week of massive learning curves here is my first attempt, I still have a lot of work to do but the basics are there.

500+ 1min light subs giving around 9 hours of data. 7 hours of lights are with a standard ZWO IR filter and the extra 2 hours is using the Optolong L-eNhance filter.

50x flat files @ 3 seconds, created using an A3 light board. These are not perfect I have just purchased a USB dimmer for this board so I can get more accurate, this is on its way from good old China.

50x Dark flat files @ 3 seconds

100x Darks

All of the above taken at 120 gain. Using a Bintel 8" Newtonian.

Hoping to get a little more control of this camera soon but I am still waiting on some items to arrive. I tried to use the Optolong filter by itself but the stacked image had stars which were too red. Maybe when I can do master flats on this filter it may turn out better.

Thanks for looking and as usual comments welcome.

Clear Skies

[AstroViking (Steve)]

Nicely done, Carl. It's quite a step up from DSLR to astro-cam, and the learning curve does take some effort to get over.

It's my understanding that you need matching flat frames for each set of light frames. So for your L-Enhance light frames, you need a set of flat frames, and a further set of flat frames for the 'no filter' set of lights.

You can get away with one set of dark frames and one set of dark flats, as you're capturing any in-camera noise such as amp glow and thermal noise.

With the ASI294 (and the 183) you can't get reliable images under 3 seconds of exposure time. There's something up with these cameras that give you bad images. So capturing bias frames is not going to happen. Stick with ~5 second flats / dark-flats and you'll be fine.

Cheers,
V

[oska (John)]

That's a great result Carl. Take every opportunity you can to practice with it and you'll get it in no time. The only 'tricky' setting is offset and usually you can start with whatever the driver uses as default. Personally I think DSLRs are harder than an astro cam for astro when all said and done.

[carlstronomy (Carl)]

Thanks guys, I am currently using the native ZWO software for my images. I have seen videos and noticed people mention offset of 30. The ZWO software does not have this option it only has gain so I am unsure what and how this effects the image. I will have to do some more research on offset.

I have already ditched the bias files, will go to 5 second subs for flats once I can dim my light pad.

I am currently using the flats from no filter so I think considering that, this image has turned out pretty good. Very hard trying to stick 30 pieces of paper and get them to hold to make some more especially at 5 seconds so they will have to do for now

One thing I noticed is the amount of data the L-eNhance filter packed in to 1 minute was huge. A little too much for me to control at this time

Clear skies

[Cyberman (Rob)]

Good work Carl. I will be following your work with astrocamera as I probably will get one eventually. I haven't got a filter but you might find you can take longer flats with filter. You seem to be getting good results with that 294 camera.
Rob

[Doogs38 (Alex)]

Nice image, Carl. The 294MC is a great camera and popular for just that reason. Its pixel size also suits longer focal length scopes and I use it with a 120ED refractor and 8” EdgeHD SCT. Yep, it can (apparently) be fussy about calibration but I’ve never had any issues with calibrating my lights. As stated below, just keep the flats and darkflats ~5secs and avoid bias frames. Or, as I do in PI’s stacker (WBPP), use the darkflats as your bias frames. I also mainly use 120 gain and -10 deg cooling. I have also experimented with higher gain and shorter exposures (thanks to the good results shown by Alex) and produced good results when using my SCT’s native very long focal length. Alex

[carlstronomy (Carl)]

Thanks Rob, I will post more images as I get them running

Alex, the images I took were at 15 degrees. I have been scared to run them down further as yet. I will work down as I go, I was wondering what temperature do these camera's come down to in our hot summer weather?

Clear skies

Carl

[AstroViking (Steve)]

Hi Carl,

The data sheet for the camera should give the minimum temperature it will go down to. From memory, the '183 / '294 should go to about 30 degrees C below ambient temperature.

I run mine at 0C without any troubles, even in the middle of summer. I could probably go lower if I desired...

Cheers,
V.

[carlstronomy (Carl)]

V, thanks mate. When I take my next flats I will drop my temperature to 0, that will reduce some noise and help increase the quality of the image.

This camera has a lot of bad vibes around it but from what I have learned it just needs to be treated in a certain way to give great results.

Clear skies

Carl

[AstroViking (Steve)]

No worries at all, Carl. The '294 can be described as a classic car - treat it right with the attention to detail it deserves and it will look after you.

[Doogs38 (Alex)]

I settled for -10c and have never had trouble reaching that temp although I have not yet experienced a SEQLD summer while doing astro. In fact, my library of calibration frames are all done at -10c. Note, the 294’s calibration frames (both MC and MM) can look very funky due sensor weirdness. However, they work perfectly if use an ADU of ~30k and 5secs. Alex

Originally Posted by carlstronomy

Thanks Rob, I will post more images as I get them running

Alex, the images I took were at 15 degrees. I have been scared to run them down further as yet. I will work down as I go, I was wondering what temperature do these camera's come down to in our hot summer weather?

Clear skies

Carl

[Bodon (Steve)]

Carl well done there with that setup! Im sure you will tame that camera. Keep them coming.

[carlstronomy (Carl)]

Learning and more learning, also waiting for some clear skies

Here is a couple of hours on NGC6960 using the new camera and a standard IR cut filter.

30sec lights
30sec darks
5 sec flats
5 sec dark flats

The image is not framed well and does not fit in this scope well. Just trying to get some nice detail out of the 294MC.

Comments welcome

Clear skies

[carlstronomy (Carl)]

One more for today, I am fairly happy with these images using a standard IR cut filter.

NGC253

30 sec lights
30 sec dark
5 sec flats
5 sec dark flats

Next is to test out the Optolong N-eNhance filter

Clear skies