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

Problems filming planets (fps so low)

  • Please log in to reply
7 replies to this topic

#1 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 23 July 2021 - 05:48 PM

Hi!

 

I have problems filming planets because the fps are extremely low.
Despite ROI and High Speed mode, I can't get past about 30 fps with my ZWO ASI 178 MC.

 

Does anyone have any ideas where the problem might be?

I have already purchased a new high quality USB3 cable. No difference.
My computer is a laptop with SSD hard drive and 8 GB RAM.

 

 

Here is still the data from the last photo attempt.

 

Camera=ZWO ASI178MC
Filter=G
Profile=Jupiter
Diameter=47.77"
Magnitude=-2.79
CMI=111.2° CMII=125.9° CMIII=302.2°  (during mid of capture)
FocalLength=900mm (F/3)
Resolution=0.55"
Filename=233657_Jup.avi
Date=230721
Start=233432.403
Mid=233657.186
End=233921.969
Start(UT)=213432.403
Mid(UT)=213657.186
End(UT)=213921.969
Duration=289.566s
Date_format=ddMMyy
Time_format=HHmmss
LT=UT +2h
Frames captured=9158
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=1x1
Bit depth=8bit
Debayer=yes
DebayerAlgorithm=NearestNeighbor
BayerPattern=RG
ROI=1728x1112
ROI(Offset)=384x544
FPS (avg.)=31
Shutter=17.27ms
Gain=293 (57%)
AutoExposure=off
AutoGain=off
Brightness=10
HardwareBin=off
HighSpeed=on
USBTraffic=60
WBlue=90
WRed=70
Histogramm(min)=0
Histogramm(max)=88
Histogramm=34%
Noise(avg.deviation)=n/a
eADU=0.031
AutoAlign=true
PreFilter=none
Limit=none
Sensor temperature=29.0°C

 

 

Even smaller ROIs won't work, otherwise I won't be able to track my Dobsonian. But still, according to the manufacturer, the camera should be able to do more fps (even at full resolution).

 

I hope for your help,
Mario

 



#2 Ittaku

Ittaku

    Apollo

  • -----
  • Posts: 1,499
  • Joined: 09 Aug 2020
  • Loc: Melbourne, Australia

Posted 23 July 2021 - 05:52 PM

Disable debayer.


  • happylimpet and mayhem13 like this

#3 Tulloch

Tulloch

    Gemini

  • *****
  • Posts: 3,428
  • Joined: 02 Mar 2019
  • Loc: Melbourne, Australia

Posted 23 July 2021 - 06:09 PM

Also, your shutter speed is too long (17.27 ms), which gives you a maximum framerate of (1 / 0.01727 = ) 58 fps, your FOV is too large (reduce the height to the FOV to about the planet's height + 50%) and your USBTraffic value is too low (needs to be at least 80 to 100).

 

Hope this helps,

 

Andrew


Edited by Tulloch, 23 July 2021 - 06:11 PM.

  • happylimpet and mayhem13 like this

#4 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 23 July 2021 - 06:20 PM

Thanks.

 

 

Disable debayer.

I tried that, but it doesn't change the speed.

 

 

Also, your shutter speed is too long (17.27 ms), which gives you a maximum framerate of (1 / 0.01727 = ) 58 fps, your FOV is too large (reduce the height to the FOV to about the planet's height + 50%) and your USBTraffic value is too low (needs to be at least 80 to 100).

 

Thanks! 
I will try to make the shutter speed lower and the gain higher. Correct?

I can't make the FOV lower because then I can't manage to move the Dobson manually with smaler FOV without losing the planet from the picture. But yes, that would probably help.

When I set the USB-Traffic higher, the picture freezes constantly and the transfer stops.

But I try that all!

 

Mario


  • Tulloch likes this

#5 Sky King

Sky King

    Viking 1

  • *****
  • Posts: 607
  • Joined: 16 Mar 2017
  • Loc: Arizona

Posted 23 July 2021 - 06:24 PM

Your camera shows: Supported resolution

 

10bit ADC/14bit ADC
3096×2080 60fps / 30fps
USB3.0
2560×2048 62fps / 31fps
2048×1080 116fps / 58fps
1280×960 130fps / 65fps
800×600 204.7fps / 102.3fps
640×480 253.1fps / 126.5fps
320×240 479.7fps / 239.8fps

 

You're using Sharpcap? Go to File, Settings, Filenames, Speed Test and run the speed test. Maybe disk write speed is slow. 


Edited by Sky King, 23 July 2021 - 07:07 PM.


#6 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 23 July 2021 - 06:41 PM

Thanks!

 

That is not USB 3, right?

USB.jpg

 

But my computer should have USB-3.

I do not know anything about it. Can someone explain to me how I can check or change this?

Or is my hard disk that slow? It is SSD.

 

Mario

 

 

EDIT:

USB 3.jpg


Edited by Mario_S, 23 July 2021 - 06:47 PM.


#7 Sky King

Sky King

    Viking 1

  • *****
  • Posts: 607
  • Joined: 16 Mar 2017
  • Loc: Arizona

Posted 23 July 2021 - 07:04 PM

"That is not USB 3, right?"  It's a disk speed test. So this tests the computer's write speeds. You can only go as fast as the slowest link in the chain.  Maybe try a different usb 3 cable.

 

Here's another thread about the ASI178's frame rates.

 

Here's a post from ZWO on configuration for higher frame rates.


Edited by Sky King, 23 July 2021 - 07:57 PM.


#8 YossiZ

YossiZ

    Mariner 2

  • -----
  • Posts: 205
  • Joined: 21 Mar 2021

Posted 23 July 2021 - 10:30 PM

I managed to get ~90fps with ASI178MC, 350 gain, 5ms exposures, 1024x768. I will try a little higher gains and saw that I also had 60 USB limit, so maybe the rate can get a little higher.

Edited by YossiZ, 23 July 2021 - 10:30 PM.

  • Mario_S likes this


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