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Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 6:32 am
by Nittany
Hello Robin -
Here is the picture with darks and @ 15s and 300 gain. Any further recommendations? Just stack longer?
Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 6:34 am
by Nittany
Still looks grainy.
Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 11:07 am
by turfpit
Nittany
This is your image with noise reduction applied (Neat Image in this example).
- Stack_80frames_1200s_WithDisplayStretch_1_filtered.jpg (935.46 KiB) Viewed 1842 times
From the ZWO website, the read noise v gain graph for the ASI678. Keep gain > 182 to take advantage of the HCG mode. I would try gain=200 (with the same exposure) and increase the frames stacked (how many depends on your tracking).
- ASI678-read-noise.JPG (31.18 KiB) Viewed 1842 times
Note that the ASI678 is described as a Planetary Camera on the ZWO website. Bortle 8 skies will always be against you for deep sky.
Dave
Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 12:42 pm
by FstarGazer
Hey Turfpit, what kind of noise reduction did you do on this? Had some extraordinary noise in my recent pictures as well. I figure it was too low exposure time of only 20s on M1 with gain 200 and the 533 mc pro under a full moon.
Nice result on m51 though.
Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 12:56 pm
by turfpit
Thanks. Neat Image was used in this example. There are many image processing applications which have noise reduction facilities. Google astro images noise reduction.
Full moon will not have helped. In my opinion, M1 (and M51) are not 20s exposure objects (unless using a RASA scope or Hyperstar) if good results are required.
Dave
Re: M51 Image - Not sure what am i doing wrong in my settings
Posted: Mon Apr 10, 2023 1:04 pm
by Nittany
Thank you Turfpit. Really appreciate your recommendation and suggestion. I like noise reduction you did on this. I will try it in Photoshop (Assume i would be able to do that?)
Also, yes ASI678MC is a planetary camera and i am tracking to keep above 182. I normally start with 200 and see if it stacks, if not then i will increase gain.Thats how i got to 300. For this picture, i stacked 21 mins. Maybe i need to stack 30 mins.
Thanks again.
turfpit wrote: Mon Apr 10, 2023 11:07 am
Nittany
This is your image with noise reduction applied (Neat Image in this example).
Stack_80frames_1200s_WithDisplayStretch_1_filtered.jpg
From the ZWO website, the read noise v gain graph for the ASI678. Keep gain > 182 to take advantage of the HCG mode. I would try gain=200 (with the same exposure) and increase the frames stacked (how many depends on your tracking).
ASI678-read-noise.JPG
Note that the ASI678 is described as a Planetary Camera on the ZWO website. Bortle 8 skies will always be against you for deep sky.
Dave