Canon EOS 1000Da ISO experience (200 / 400 / 800 ?) - Forums

Topic starter

Jul 24, 2017

Hi, using the rain over the weekend I read a bit about the best ISO for my Canon1000Da.

Reading this site
http://dslr-astrophotography.com/iso-values-canon-cameras/

which also references Sensorgen:
http://www.sensorgen.info/CanonEOS-1000D.html

I am still not a hundred percent sure as of which ISO would be best to use. In the past I have always been using ISO400 but I want to experiment a bit with ISO800 the next time the sky is clear. Somehow I am not sure if I also should try the main suggested ISO200 as the exposure times will be quite high then and I am not sure if more dithered subs with a bit more noise are better than fewer (but longer) lower noise exposures.

Has anyone of you already made these tests with a 1000D?

Looking forward to hear your opinions

Best Frank

Engaging

bobzeq25

Jul 26, 2017 · Edited: Jul 26, 2017

Depends a bit on how many subs you shoot, and your target, but…

There 's a large drop in read noise going from 400 to 800, I think you at least want to do that. A significant further drop going to 1600,
so that's what the first site recommends. I agree.

Frank Schmitz

Topic starter

Jul 26, 2017

Thanks Bob, so the dynamic range drop does not have such an impact?
Best Frank

Gary Plummer

Jul 29, 2017

You can negate most of your read noise by creating a master BIAS frame to calibrate your lights; along with a master dark. I use around 200 images for the BIAS at the ISO I use, doesn't take long. I prefer to keep my ISO at 400 or 800 so I don't give up too much dynamic range. My master dark is from 72 frames, I have them also at 400 and 800 ISO at both 3 minutes and 5 minutes.

Helpful

Frank Schmitz

Topic starter

Jul 29, 2017

Thanks Gary much appreciated!

Roger Redcat

Aug 30, 2017 · Edited: Aug 30, 2017

Frank Schmitz:
Hi, using the rain over the weekend I read a bit about the best ISO for my Canon1000Da.Reading this site
http://dslr-astrophotography.com/iso-values-canon-cameras/

which also references Sensorgen:
http://www.sensorgen.info/CanonEOS-1000D.html

I am still not a hundred percent sure as of which ISO would be best to use. In the past I have always been using ISO400 but I want to experiment a bit with ISO800 the next time the sky is clear. Somehow I am not sure if I also should try the main suggested ISO200 as the exposure times will be quite high then and I am not sure if more dithered subs with a bit more noise are better than fewer (but longer) lower noise exposures.

Has anyone of you already made these tests with a 1000D?

Looking forward to hear your opinions
Best Frank

i`ve always been told and used 800 ISO @ 5 Minute subs
Roger 8)

Frank Schmitz

Topic starter

Aug 30, 2017 · Edited: Aug 30, 2017

Thanks Roger, I've experimented now a bit with 200/400/800 ISO and still not hundred percent sure.

When I used 200 ISO I found the colors a bit more vivid (http://www.astrobin.com/307107/F/), however the 800er subs are also very good and I was able to collect a lot more of them (http://www.astrobin.com/309856/D/). At the moment I am switching depending on how much time I have for imaging until the object moves out of my sight…

Next time I get the chance I will do a direct comparison between a night worth of subs on M33 one with ISO 800 and one with ISO 200. This will be very subjective of course and also dependent on seeing but I am keen to see the results

Best F

Helpful Engaging

Jarkko Suominen

Aug 31, 2017 · Edited: Aug 31, 2017

Here is Andromeda with ISO800 to compare somehow (we have different scopes, different processing programs etc… but you'll get the idea!) to Franks pic: http://www.astrobin.com/309971/?nc=user

ofcourse I live in Finland and we just started to have pretty cold nights…

Frank Schmitz

Topic starter

Sep 1, 2017

Thanks Jarkoo, very interesting.

Manuel Frattini

Sep 1, 2017

Hi Frank,I have been practicing for less than a year, and from what I have learned, 800iso is very suitable for many purposes.But it also depends very much on your sky, on your material, and on the object you wish to image (dark or very bright), you can also on the same object, play precisely on the sensitivity (or the time of pose) Get the detail, like on the heart of M42 for example!So, it is only with very little experience that I answer you, but I hope it will be useful to you!Have a good day,

Manu.

Gary Plummer

Sep 2, 2017

I would also take the target into consideration, if a bright one like M42/3 then I'd keep the ISO down to maximize the dynamic range and full well capacity. If the target is faint then it'd probably be worth increasing the amplification a little but I always stick between 200 and 800 iso regardless and don't think the sacrifice of dynamic range and full well capacity justifies high iso settings. Far better to get more exposure time I believe.