How noisy are 900s and 1800s subs at ISO800

[Psychobilly]

Following on from a question posted elsewhere...

Heres a single 900s sub of NGC7000 IC5070 at ISO800 with the 1000D

and heres a single 1800s sub of M27 again at ISO800 with the 1000D

Only "processing" to both subs is raising the black point... no flats , no bias, no darks, no curves etc...

Not bad for what was when I bought it a £289 camera complete with a 18-55 IS lens

Peter...

[skye at night]

Interesting..

that 900 is pretty good all over...

the 1800 is just beginning to test your guiding Peter... (so very! good)

But I suppose it is a test of noise and not real practice. But good to note.

Steve

[Psychobilly]

The 900 is with the megrez 72 and FF III so only around 432mm FL the 1800s is CPC800 at around F6.3 so around 120mm FL ... I dont think the spacing right with the CPC 6.3 setup and needs a bit of worthe 2" filter is in a Pair of Borg adaptors before the FR and a fixed 55mm SCT - T adaptor is fitted to the reducer...

SO it should be around the right 110mm distance... the star shapes in the central 50% portion of the image are probably good enough to use but i would like to be able to use more of the FOV...

Has anyone got CCD inspector and can tell me if the Reducer Sensor distance needs to be increased or decreased?

[foundaplanet]

I had no idea that such a good result could be achieved with the 1000d.

Is this modded or unmodded.

[Psychobilly]

Modded - It has had the standard filter replaced with a Baader BCF one . This was done before people fully understood the contribution of the various elements of the multi-part filter stack employed in the newer Canon DSLR's . The camera needed to be able to reach infinity focus with camaera lenses so stgaright filter removal like my 350D was not an option.

Things have moved on a lot since 2009... the very long subs wer emainly to test the Tracking and Guiding of my reworked CPC800 that used to live in the obs... It hasn't been in there for nearly 2 years now and the obs is used as a garden shed

Peter...

[laser_jock99]

My Fuji DSLR's seem to have quite low noise compared to other DSLR pictures I have seen, especially when used in the depths of winter! I suppose low ambient temperature must help. Whether the low noise anything to do with Fuji Super CCD SR technology I'm not sure? http://www.dpreview..../fujisuperccdsr As an example here is straight RAW conversion of a 1200 second sub at ISO3200 (ambient probably about -4 deg C) It is a shame Fuji stopped making DSLR's- I'm sure they were on to something?