M101 from Blacklands DSC

[Carole]

Probably not the best choice of objects with my small refractor, but on the first night had to choose an area between clouds, and having started wanted to get more data the following night.  Also while I was imaging this the first night there were distant lightning flashes going on, but didn't seem to affect the subs as far as I could see.

So this is:
14 x 600secs WO ZS71 with focal reducer bringing the FR down to 4.8
Atik383L luminance no darks
For some reason this image appears too light on OAS gallery but looks a much darker background in Photoshop.

Original Image deleted because the sky background looks grey on the gallery:
this is the link from Astrobin:

Larger image (on gallery which incidentally doesn't look grey like the small size does and I'm even more confused)
http://gallery.orpington-astronomy.org.uk/albums/userpics/10047/M101_14_x_600secs_Blacklands_CROP.png

[Les R]

For some reason this image appears too light on OAS gallery but looks a much darker background in Photoshop.

Very good Carole.

Do you mean the sky looks dark grey and not black?

[Carole]

This is with colour added from an image I did at kelling 2 years ago with DSLR.  

Had to crop quite a bit because of the DSLR crop.

[Carole]

Do you mean the sky looks dark grey and not black?

Yes Les, looks perfectly fine on Photoshop.

I've deleted the gallery link in the first post now and added the one from Astrobin.
Strange why that happened.

Carole

[Rick]

Yeah, for some odd reason the gallery's re-sizing has done some re-balancing too. The full-sized image on the gallery is fine.

[Carole]

Thanks Rick, it's also done the same with my following image.

Carole

[Rick]

Looks like it's something to do with monochrome png files. What are the settings on your PNG file?

[Carole]

What sort of settings are you looking for Rick?

carole

[Mike]

Nice image Carole, lots of details, though the background looks too black to me. I always think images with clipped black backgrounds look unnatural. The sky even in a very dark site is never black.

[Carole]

It's not clipped Mike. Not in levels curves or in the histogram I am always careful not to do that.

Carole

[mickw]

The mono version looks better, with colour added there appears to be horizontal banding and it's gone "soft"

I think you've had this issue with the Canon before

[MarkS]

The B&W image is good. Lots of faint fuzzies in the background and a great "edge on" galaxy bottom right.

In my opinion, adding the colour doesn't do it justice because the colour is too noisy.

[Carole]

Thanks Mark,

adding the colour doesn't do it justice because the colour is too noisy.

Yes I think you're right, another one I'll have to do those pesky RGB filters on, but it will have to wait until I am at a dark site as M101 is no good from where I live.

Carole

[JohnP]

Again - very nice Carole. Prefer the full frame B&W myself. Looks like a small top to bottom gradient to me. Also any idea what the feint nebulosity is bottom left - is this real or is it some kind of internal reflection..?


Nice image though - John

[Carole]

Thanks John.  Blimey you have eyes like a hawk, there is some sort of feint "nebulosity" as you describe but I am blowed if I can see it on either of the images I have attached. 

I am going to examine the subs done on the first night and those done on the 2nd night separately as there was distant lightning on the first night not far from the direction I was imaging, to see whether it appears on both nights.  Will report back when I have done so.

As regards the gradient, I did not notice it but that's easily fixed.  Thanks for pointing it out.

Carole