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Old 11-10-2021, 03:15 PM
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Marko of Oz (Mark)
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Helix

This is my first guided shot of anything and I kind of leapt into the deep end after buying a HEQ5 Pro. Still getting my head around using eqmod, Stellarium, PHD2 and Astrophotography Tool to control/automate everything, but it all seems to integrate nicely.

Using HEQ5 Pro, Evostar ED80, Canon 700D, Svbony 50mm guidescope, ASI120mm mini autoguider all plugged into my aging Acer laptop that has 4 usb ports(bonus).

100 X 3 min exposures, 30 flats and 50 bias frames. No darks because 1) I'm lazy and 2) There seems to be those that say use them with a dslr and those that say don't.

Processing with Deepsky Stacker and Startools.

I'm pretty happy with it but am I pushing the limits of my dslr? Or have I picked a hard target to practice on? Thoughts?

thanks for looking

Mark
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Old 11-10-2021, 03:48 PM
etill (Elliot)
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It's a great shot, I like the wider field this one is normally bit closer.

There's some banding I can see in it though that looks like what I got with my 60D when I didn't use darks. I definitely found darks were needed for almost everything I did with my DSLR, especially beyond 30 sec subs.
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Old 11-10-2021, 05:36 PM
Startrek (Martin)
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Mark,
Nice image of the Helix
Well done !
Your using exactly the same software as Iíve used for a long time, although for 16 months Iíve been using a ZWO 2600MC cooled OSC ( I used my Canon 600D for +3 years )
In regard to DSLRís and subs longer than 60 sec , my advice is take your darks ( say 20 ) to reduce thermal noise and dither your subs to reduce fixed pattern noise and dark current
Astrophotography tool has the dither function located under the Guide tab , just enable it to on , dither every frame and use dither distance 1 or 2 depending on how long your mount recovers from a dither.
This will definitely improve your images noise floor which is evident in your image
My Canon 600D use to run at 21C in winter and up to 35C in summer , a recipe for lots of noise , so I took darks and dithered to reduce this which did work well.
Other than the above, to reduce noise further , take shorter subs ( say 60sec to 120 sec ) but hundreds and hundreds of them
Cheers
Martin
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Old 11-10-2021, 06:04 PM
Startrek (Martin)
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Quote:
Originally Posted by Startrek View Post
Mark,
Nice image of the Helix
Well done !
Your using exactly the same software as Iíve used for a long time, although for 16 months Iíve been using a ZWO 2600MC cooled OSC ( I used my Canon 600D for +3 years )
In regard to DSLRís and subs longer than 60 sec , my advice is take your darks ( say 20 ) to reduce thermal noise and dither your subs to reduce fixed pattern noise and dark current
Astrophotography tool has the dither function located under the Guide tab , just enable it to on , dither every frame and use dither distance 1 or 2 depending on how long your mount recovers from a dither.
This will definitely improve your images noise floor which is evident in your image
My Canon 600D use to run at 21C in winter and up to 35C in summer , a recipe for lots of noise , so I took darks and dithered to reduce this which did work well.
Other than the above, to reduce noise further , take shorter subs ( say 60sec to 120 sec ) but hundreds and hundreds of them
Cheers
Martin
PS: Forgot to mention that the Helix is an extremely difficult target to image at any level , so you done very well to expose a fair amount of detail
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Old 11-10-2021, 06:37 PM
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Marko of Oz (Mark)
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Thanks for the comments Elliot and Martin. I'll take all the advice onboard.

Mark
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Old 11-10-2021, 06:42 PM
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Excellent...start saving for a narrow band cooled camera as you clearly have a knack to produce a great image.
Frankly I am surprised how good your image presents so congratulations.
Alex
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Old 11-10-2021, 06:51 PM
Stephane
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Mark, your first image is really awesome. If my first one comes out nearly as good, I will be VERY happy!

Some might have tips for the banding, but I wouldnít worry too much as itís a great overall result.

Cheers,
Stťphane
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Old 11-10-2021, 07:27 PM
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Sunfish (Ray)
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Great image. Really good detail. . Guiding makes all sorts of things possible.

Takes darks though. Essential I think. With a DSLR and darks it is bias frames that are optional I think , depending on the software.
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Old 11-10-2021, 07:29 PM
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mswhin63 (Malcolm)
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Hi Mark,

Nice image better than my attempt although I have not tried to push the limits as far as 3 minutes.
The bars possibly due to the flats, I had the same problem although different bands. The issue in my case was the power supply to operate the Electro luminance panel.

If you use an EL display for flats then try moving around the power supply away from the camera as they are extremely noisy switching power supplies.

Quote:
Originally Posted by Marko of Oz View Post
This is my first guided shot of anything and I kind of leapt into the deep end after buying a HEQ5 Pro. Still getting my head around using eqmod, Stellarium, PHD2 and Astrophotography Tool to control/automate everything, but it all seems to integrate nicely.

Using HEQ5 Pro, Evostar ED80, Canon 700D, Svbony 50mm guidescope, ASI120mm mini autoguider all plugged into my aging Acer laptop that has 4 usb ports(bonus).

100 X 3 min exposures, 30 flats and 50 bias frames. No darks because 1) I'm lazy and 2) There seems to be those that say use them with a dslr and those that say don't.

Processing with Deepsky Stacker and Startools.

I'm pretty happy with it but am I pushing the limits of my dslr? Or have I picked a hard target to practice on? Thoughts?

thanks for looking

Mark
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