NGC891- Astronomy and astrophotography CCD camera images

21st November 2005
Object name: NGC891
Popular name:
Object type: Galaxy
Magnitude: 10.9
Size: 11.7 1.6
Position angle: 2
Classification: Sb
Apparent RA: 02 22 33.0 Apparent Dec: +42 20 50
Constellation: Andromeda

I have opened my NGC 891 account for this season! NGC 891 is a classic edge on galaxy in Andromeda some 10 million light years away. Every time I visit this object, it always seems to be a bit dimmer than I was expecting. So with a webcam its a challange to get the full extent without going noisy. Last night I captured some unfiltered frames of this object seen on the right. I also attempted to combine these with some RGB data from December 2005, but I am not pleased with the result. See below.

A dust blob has also appeared on the camera. Time for a clean! Reviewing my previous shots here and here (Scroll to bottom) I see an improvement in this image. I think however that I can do better as transparency was poor, exposure length was only 30s and guiding at 400mm was not spot on.

Captured in k3ccdtools with BW SC3 toucam webcam. autoguided with GuideDog. Each of the 4 avis stacked in registax and exported FIT32. Coregistered and colour scaled in IRIS. Colour layer exported from iris as psd. L layer fits and colour layer combined in photoshop. Curves on L and colour layers. 50% with darken faded minimum filter on feathered selected highlights of L layer. Multiple LLRGB layering to produce final image.

Exposure Details :

Red 40x15s on 200mm @ F5 with SC3.5
Blue 40x15s on 200mm @ F5 with SC3.5
Green 40x15s on 200mm @ F5 with SC3.5
60x30s on 200mm @ F5 with SC3.5

Curdridge Observatory, Southampton,UK