So my first crack using a dedicated astro camera and I get this as a master dark (in APP). What the heck?
Mike
Mike
What has happened here
What camera do you have? Parameters?
I think it's not as bad as you may think
It's called amp glow
Some info, for example, here
I think it's not as bad as you may think
It's called amp glow
Some info, for example, here
It's a ZWO 294MC Pro. I kinda expected amp glow, but I don't really know what that is, or how it affects things. I think gain was about what the medium setting from my ASIAir Pro ~ probably around 150 ~ I was just guessing.
*posted before I read the link to the ZWO info page. Still, seems excessive to me.
*posted before I read the link to the ZWO info page. Still, seems excessive to me.
My master dark (in PixInsight) with 300 secs exposure at unity gain on an ASI1600MM looks more like this (some amp glow, but not like yours): Try deepskystacker or the free Pixinsight trial to see if you get the same result. Also, how many seconds were your darks?
Yep, amp glow. Mine does the same. But your master dark should remove it from your calibrated lights
Concise
Entirely normal dark frame from that camera. Mine are just the same.
Well Written
Yep, dark from 294 MM, I have the similar. Darks, flats and dark flats will handle it. Dark 600 sec., gain 120. offset 30, -25 C, BIN 2:2
For comparison -dark from 1600 MM-Pro, 600 sec., gain 139, offset 21, -14C, BIN 1:1. ASI 1600 has less evident glow as a proven fact. You would need only darks to eliminate it.
Mike Butorac:
It's a ZWO 294MC Pro. I kinda expected amp glow, but I don't really know what that is, or how it affects things. I think gain was about what the medium setting from my ASIAir Pro ~ probably around 150 ~ I was just guessing.
*posted before I read the link to the ZWO info page. Still, seems excessive to me.
I would freak too as first experience, to be honest
However, if you carry on the normal calibration steps of your lights matching appropriately darks/flats, you will have very nice results
A lot of people use unity gain of 120. According to zwo specs graphs there’s no great advantage in setting you cooling below -15’c. I use -10’c myself.
Use dark flats instead of bias seems to be the way to go also.
There’s a lot talk on forums about calibration frames with 294mc…
so try using 4 seconds for flats and dark flats. It’s worked fine for me.
I think it’s a great Astro cam, great for EAA also.
Enjoy
Use dark flats instead of bias seems to be the way to go also.
There’s a lot talk on forums about calibration frames with 294mc…
so try using 4 seconds for flats and dark flats. It’s worked fine for me.
I think it’s a great Astro cam, great for EAA also.
Enjoy
Padraig Farrell:
A lot of people use unity gain of 120. According to zwo specs graphs there’s no great advantage in setting you cooling below -15’c. I use -10’c myself.
Use dark flats instead of bias seems to be the way to go also.
There’s a lot talk on forums about calibration frames with 294mc…
so try using 4 seconds for flats and dark flats. It’s worked fine for me.
I think it’s a great Astro cam, great for EAA also.
Enjoy
I would fully agree with your statements with the only correction: -20C is the point where noise is negligible. http://www.astrosurf.com/buil/asi294mm.html Excellent review
I must give that a go, thanks. 👍
Have you seen this video. ?
https://youtu.be/3RH93UvP358
Dr. Robin Glover from Sharpcap
Have you seen this video. ?
https://youtu.be/3RH93UvP358
Dr. Robin Glover from Sharpcap
Padraig Farrell:
I must give that a go, thanks. 👍
Have you seen this video. ?
https://youtu.be/3RH93UvP358
Dr. Robin Glover from Sharpcap
Very informative, thanks! As a summary: in subarbian f6 needs 180 sec with NB filters, cooling temperature -15 C, more or less. Sounds reasonable and scientifically based. You can also read wounderfull site of Buil, he is one of the fathers of modern CCD cameras, a lot to learn from him. ZWO states that -20 C is the perfect temperature for 294, Buil tested on -15 C, but mentioned the -20 C equivalent (see above). I am thinking to start imaging with 294 with gain 120/offset 30, BIN 2 (BIN 1 sounds too good to be true, it is 12 bit afterword in comparison with 14 bit BIN 2) and exposition 300 sec. I saw many images with the same camera and 180 sec.exposition - they lack of contrast, IMHO. May be I will switch to 180, possible too.
Helpful
Adel Kildeev:
I am thinking to start imaging with 294 with gain 120/offset 30, BIN 2 (BIN 1 sounds too good to be true, it is 12 bit afterword in comparison with 14 bit BIN 2) and exposition 300 sec. I saw many images with the same camera and 180 sec.exposition - they lack of contrast, IMHO. May be I will switch to 180, possible too.
On my ASI 1600MM at unity gain -10C in a suburban area on an F4.5 scope I'm using:
30secs for lum
90 secs for RGB
Anywhere between 180 secs and 300 secs for 7nm narrowband; looking at the subs ADU numbers I should theoretically go with 240 secs
Of course this all depends on the target and I may be tempted to keep Ha at 180secs and push SII and OIII to 300 secs.
No point in going any longer with my light pollution.
Here's to moving house to a darker sky location one day
Helpful
I tried darks BIN 1:1 120 gain/30 offset 300 sec.- amp glow is barely visible, unlike BIN 2:2, very interesting 🤔
2021-12-21_14-30-17_1_-22.30_300.00s_0018.jpg
2021-12-21_14-30-17_1_-22.30_300.00s_0018.jpg
I really need to try BIN 1:1 with my f6 APO