#1  
Old 26-05-2021, 01:59 PM
DiscoDuck's Avatar
DiscoDuck (Paul)
Raider Nation

DiscoDuck is offline
 
Join Date: Apr 2014
Location: Adelaide
Posts: 569
294MM-Pro read noise

I have a question about the 294MM-Pro and its read noise. The read noise graphs available seem to show a very similar read noise for both Bin 2x2 and Bin 1x1 modes - at least at the middle and upper end of the gain values.

My na´ve understanding was that CMOS cameras did not implement the same hardware binning as CCDs, and so that 2x2 binning should double the read noise over 1x1 bin (double as the four individual read noises add in quadrature). i.e. I thought that CMOS binning in hardware was pointless (other than quicker download) and might as well be done in software. But these figures contradict that.

Is there some hardware binning being done here and there really is a hardware Bin 2x2 benefit? Also what happens just below unit gain at Bin 2 (but NOT in Bin1) to make the read noise jump significantly?

Just trying to understand if this camera is as good as the specs seem to show before I look to add it to my wishlist for approval by the financial controller in the house to replace my 1600MM
Reply With Quote
  #2  
Old 27-05-2021, 12:38 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,045
The 294 has a 4 subpixel structure which is unique. Hence the genuine 2x2 binning and its benefits.

Other CMOS don't do hardware binning except for the QHY600 and perhaps the 268.

Banding at 47mp ca be the real issue with the 294.

Greg.
Reply With Quote
  #3  
Old 28-05-2021, 06:33 PM
DiscoDuck's Avatar
DiscoDuck (Paul)
Raider Nation

DiscoDuck is offline
 
Join Date: Apr 2014
Location: Adelaide
Posts: 569
Thanks Greg.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 08:20 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Advertisement
NexDome Observatories
Advertisement
Limpet Controller
Advertisement
Bintel
Advertisement
Testar
Advertisement
Astronomy and Electronics Centre
Advertisement