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

Canon eos 550D, noise reduction for long exposures and high ISOs,activate or not activate?

  • Please log in to reply
3 replies to this topic

#1 Julian Sanz

Julian Sanz

    Mariner 2

  • -----
  • topic starter
  • Posts: 253
  • Joined: 19 Jan 2020

Posted 19 June 2021 - 04:19 AM

Hi,I read that having noise reduction for long exposures and high ISOs activated in the canons, that causes data, signal,
by mistaking them for noise, and advise deactivating them.
From your experience, do you agree with that

#2 Boeglewatcher

Boeglewatcher

    Mariner 2

  • -----
  • Posts: 206
  • Joined: 30 Jul 2020
  • Loc: Regensburg, Germany

Posted 19 June 2021 - 05:37 AM

I understand that the build in noise reduction is based on taking a corresponding dark, then substract the dark from the light. Essentially, what you do in pre processing anyway (and we don’t take our darks during precious star gazing time).

so, I don’t use the internal noise reduction of my canon but take separate darks and use a Masterdark in pre processing.

cs Joachim 


Edited by Boeglewatcher, 19 June 2021 - 07:58 AM.

  • Julian Sanz likes this

#3 Bob Koch

Bob Koch

    Lift Off

  • -----
  • Posts: 21
  • Joined: 05 Oct 2013
  • Loc: Broken Arrow, OK

Posted 19 June 2021 - 06:49 AM

You want to disable in camera noise reduction and take dark frames to match your lights. My modded 550d is quite noisy above 10c and I have found that iso 800 is best with 1600 acceptable with some loss of dynamic range. I usally use mine in winter when temps are pretty cold in my area.

 

  Bob


  • Julian Sanz likes this

#4 daveco2

daveco2

    Mariner 2

  • -----
  • Posts: 220
  • Joined: 29 Aug 2016
  • Loc: Torrance, CA

Posted 19 June 2021 - 07:06 AM

Yes, what boggle said. My Sony has a long exposure noise reduction similar to Canon. The noise reduction routine takes the same amount of time as the original exposure, halving the available time to collect the original data. Better to apply darks to the data in post processing when time is much less precious.


  • Julian Sanz 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