Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

TEST: ASI1600MM-Cool

  • Please log in to reply
660 replies to this topic

#551 FiremanDan

FiremanDan

    Aurora

  • *****
  • Posts: 4,848
  • Joined: 11 Apr 2014
  • Loc: Virginia

Posted 30 April 2016 - 12:05 PM

My mistake :undecided:  KAF bin1 (12.4.2015), 1600 bin2 (30.4.2016). Now is to late for new image! At first clear night I will capture 180 sec!

 

RAW: NGC6888, 900sec

attachicon.gif6888_ASI1600.jpg

 

I am FAR from an expert, but I don't see much amp glow on this. 
Am I just confusing amp glow for Nebulosity? I was looking at Astrobin and comparing this with other h-alpha examples and this single exposure is looking pretty good. 

I hate to keep asking question and being picky about this, but this is a lot of money for me and I'd like to spend my money as wisely as possible. This despite the amp glow seems to be one of the better choices I have. 


  • TimN and ManicSponge like this

#552 Herra Kuulapaa

Herra Kuulapaa

    Viking 1

  • -----
  • Posts: 513
  • Joined: 10 Dec 2014
  • Loc: Vantaa, Finland

Posted 30 April 2016 - 12:27 PM

I currently use a Nikon D5100 with an older Exmor Sensor that is better than the ASI1600 sensor in most respects. However, the D5100 is isoless at the around 3e-. This sensor has a lower noise level at unity gain which is about iso 875.

 

Hi,

 

Unity gain of the D5100 should be somewhere between ISO200-320 with a full well capacity of ~15ke-. Not that there is a big difference imaging with ISO800, but just to let you know :)


Edited by Herra Kuulapaa, 30 April 2016 - 12:29 PM.


#553 FirstC8

FirstC8

    Apollo

  • -----
  • Posts: 1,118
  • Joined: 10 Mar 2016

Posted 30 April 2016 - 02:13 PM


The calibrated version is significantly better, though. I don't visually see a huge increase in random noise there either, which is good. That bit of glow...or whatever it is there, could also likely be removed with processing (i.e. DBE in PI) if you really wanted it gone (and that would be easier once you stacked a bunch of frames and the signal of that glow was stronger and better defined (and thus easier to model.)

You are right, that bit of glow at bottom left and brighter gradient towards the lower part of the frame could be moonlight effect.

But still when I looked closely at the stretched raw sub and calibrated sub, the dark subtraction seemed to have removed some good signals, not just adding some noise, however little that may be.

Make sure you use a pedestal when subtracting the dark. A proper dark subtraction should never remove signal as long as it is not clipping the data, and adding a pedestal will ensure no data is clipped.

Excuse my ignorance, can I add a pedestal in DSS?

#554 Jon Rista

Jon Rista

    ISS

  • *****
  • Posts: 24,323
  • Joined: 10 Jan 2014
  • Loc: Colorado

Posted 30 April 2016 - 02:31 PM

I am not sure about that. I haven't used DSS in over a year now...I don't think it does.



#555 keithlt

keithlt

    Surveyor 1

  • *****
  • Posts: 1,601
  • Joined: 21 Dec 2013
  • Loc: Arizona©

Posted 30 April 2016 - 02:35 PM

anyone concerned about these small pixels oversampling with short fast apo's (pixel size (um) / focal length (mm)) x 206 = arcseconds per pixel)?


  • FiremanDan likes this

#556 FiremanDan

FiremanDan

    Aurora

  • *****
  • Posts: 4,848
  • Joined: 11 Apr 2014
  • Loc: Virginia

Posted 30 April 2016 - 02:44 PM

Wouldn't you rather be over sampled va under?

#557 Jon Rista

Jon Rista

    ISS

  • *****
  • Posts: 24,323
  • Joined: 10 Jan 2014
  • Loc: Colorado

Posted 30 April 2016 - 02:45 PM

anyone concerned about these small pixels oversampling with short fast apo's (pixel size (um) / focal length (mm)) x 206 = arcseconds per pixel)?

 

Concerned about them OVERsampling? Or Undersampling? Generally speaking, I would prefer to be oversampled myself, however I don't think that 3.8 micron pixels would be oversampled at shorter focal lengths. At 600mm the image scale would be 1.3"/px, @ 450mm 1.7"/px, @ 300mm 2.6"/px. At 1.3"/px things are pretty good, but if you have 2-3" seeing it still wouldn't really be oversampled.



#558 keithlt

keithlt

    Surveyor 1

  • *****
  • Posts: 1,601
  • Joined: 21 Dec 2013
  • Loc: Arizona©

Posted 30 April 2016 - 03:00 PM

I think I included my field flattener /field reducer at a much higher value.either way wouldn't stop me from buying this camera if I was in the market.

#559 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 03:08 PM

The Pinwheel Galaxy with AS300 and ASI1600MM-Cool LRGB. Total integration time only 22.5 min. per filter (45x30sec, bin2)

M101_LRGB_ASI1600.jpg

ASI1600_AS300.jpg

 



#560 bigeastro

bigeastro

    Apollo

  • *****
  • Posts: 1,340
  • Joined: 20 Feb 2015
  • Loc: Southwest Florida

Posted 30 April 2016 - 03:36 PM

Wow APOD!  Grand prize winner for value imaging system.  The camera that is.  The rest of the setup's price points are a little higher.   22.5 min total!



#561 Thirteen

Thirteen

    Gemini

  • *****
  • Posts: 3,158
  • Joined: 12 Jul 2013
  • Loc: Milford, Michigan

Posted 30 April 2016 - 04:29 PM

This is getting good.  Wonder what the wait will be for an APS-C or full frame?


  • FiremanDan likes this

#562 FiremanDan

FiremanDan

    Aurora

  • *****
  • Posts: 4,848
  • Joined: 11 Apr 2014
  • Loc: Virginia

Posted 30 April 2016 - 04:55 PM

The Pinwheel Galaxy with AS300 and ASI1600MM-Cool LRGB. Total integration time only 22.5 min. per filter (45x30sec, bin2)

attachicon.gifM101_LRGB_ASI1600.jpg

attachicon.gifASI1600_AS300.jpg

 

WOW!   :bow:

I am so shocked that 30s subs can do this. We might have to burn ZWO at the stake! This is clearly sorcery!  :lol:

 

Is there a reason you are not shooting longer exposures? 

How fast is your telescope? 

How dark are your skies? 


  • Jon Rista likes this

#563 entilza

entilza

    Soyuz

  • *****
  • Posts: 3,774
  • Joined: 06 Oct 2014
  • Loc: Oakville, ON, Canada

Posted 30 April 2016 - 04:55 PM

That's awesome... I think your setup is amazing too.   By the way thanks for doing all this initial test work you've done a large service to the community especially those looking to get this camera.


  • scott4comp, TimN and FiremanDan like this

#564 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 05:19 PM

That's awesome... I think your setup is amazing too.   By the way thanks for doing all this initial test work you've done a large service to the community especially those looking to get this camera.

It is my pleasure ;)



#565 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 05:31 PM

Guys, I think we will must update our work with new tactics :) All new ZWO cameras (high QE, low read noise) enable us to get much sharper images than anytime before. This is fact! I just want to show you this is true :) For example look my comparison 45x20sec vs. 900sec. My friction mount G53F have very good tehnical performace but combination more shorten images give me much better result. Probably 90% all of us imaging DSO under average observing conditions and "lucky DSO imaging" is one big step forward in quality.

20sec-900sec.jpg
 

Telescope AS300 is 30-cm f4 Newton.

Sky: SQM: 21-21.30 magnitude per square arc second, I live 15 km from capital city :( Below is my night sky analize made from guy who is expert for light pollution.

svetlobno-onesnazenje-svetlost-neba-celo

 

 


  • Jon Rista and FiremanDan like this

#566 FiremanDan

FiremanDan

    Aurora

  • *****
  • Posts: 4,848
  • Joined: 11 Apr 2014
  • Loc: Virginia

Posted 30 April 2016 - 05:39 PM

Nice! Those are some dark skies! 

 

The image on the left has better, more pin point stars, but arguably more noise mostly seen in the background. 


Edited by FiremanDan, 30 April 2016 - 05:41 PM.


#567 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 05:44 PM

The Crescent Nebula is an emission nebula in the constellation Cygnus captured with ASI1600MM-Cool and H-alpha6nm. Left image (center crop) show integration 45x20sec and right 1x900sec. During imaging I had very high humidity and 900sec image was captured 1 hour earlier and higher on sky. I also think during half 20sec images telescope mirror suffer moisture  :grin:

 

I give  :waytogo: 45x20sec!

ASI1600_NB_20sec-900sec.jpg

 

 

 


  • artem2 and Jon Rista like this

#568 FirstC8

FirstC8

    Apollo

  • -----
  • Posts: 1,118
  • Joined: 10 Mar 2016

Posted 30 April 2016 - 05:44 PM

Excellent results!

Looked to me your site is better than average if shooting at near Meridian?

Although your mount is good quality, it is probably overtaxed by the heavy and long astrograph.

But hey, the new camera allows you to do short exposures and addresses guide issue and noise/amp glow concerns.

The only thing as I said earlier still a concern is if the goal is to pull out faint DSOs or structures, especially with NB filters, which will require more than 900s.
  • FiremanDan likes this

#569 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 05:57 PM

The only thing as I said earlier still a concern is if the goal is to pull out faint DSOs or structures, especially with NB filters, which will require more than 900s.

We must also test this! There is no other way :grin:


  • FiremanDan likes this

#570 FiremanDan

FiremanDan

    Aurora

  • *****
  • Posts: 4,848
  • Joined: 11 Apr 2014
  • Loc: Virginia

Posted 30 April 2016 - 06:08 PM

The 900s seems to have better contrast. It looks like the light is separating from the background noise better. I guess this is a good example of more shorter exposures vs fewer long exposures. 



#571 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 06:18 PM

The 900s seems to have better contrast.

Probably due moisture on mirror


  • FiremanDan likes this

#572 keithlt

keithlt

    Surveyor 1

  • *****
  • Posts: 1,601
  • Joined: 21 Dec 2013
  • Loc: Arizona©

Posted 30 April 2016 - 06:22 PM

Hi matejmihelcic, is this a loaner test camera or did you buy it?



#573 matejmihelcic

matejmihelcic

    Explorer 1

  • -----
  • topic starter
  • Posts: 64
  • Joined: 13 Apr 2016
  • Loc: Slovenia

Posted 30 April 2016 - 06:28 PM

Hi matejmihelcic, is this a loaner test camera or did you buy it?

This is pure beta ASI1600 :D  



#574 FirstC8

FirstC8

    Apollo

  • -----
  • Posts: 1,118
  • Joined: 10 Mar 2016

Posted 30 April 2016 - 06:52 PM

The 900s seems to have better contrast. It looks like the light is separating from the background noise better. I guess this is a good example of more shorter exposures vs fewer long exposures.

I agree, had the tracking held its ground with the long exposure it would have shown even better detail.

Up to 900s with little amp glow is good news. Unless it was simply cropped out.😊

Edited by FirstC8, 30 April 2016 - 06:54 PM.


#575 jspielberg

jspielberg

    Sputnik

  • -----
  • Posts: 36
  • Joined: 25 Oct 2014

Posted 30 April 2016 - 07:15 PM

The shorter exposures to me definitely look sharper, but the longer exposure of the crescent looks more contrasty.  I am just beginning astrophotography (with all my 2nd hand gear: gm-8, Orion 80ED and Nikon D700), and it looks like the future of amateur astrophotography is looking very bright indeed.  If I don't need to upgrade my GM8 for a while longer, because I only need solid tracking for 30 seconds with these new cameras, my wife will certainly be just as excited as I

:grouphug:




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics