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Scorpius & Antares Region with camera lens

Started by Carole, Apr 24, 2015, 13:25:45

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Carole

As some of you know I have little experience with the camera lens and tried to get this beautiful but large widefield area.  It failed to produce any detail, so this is a single 5min sub.
Modified Canon 450D and nifty 50 lens.

It does just about show the globular cluster M4, and also Saturn which is sitting at the top of the scorpion's claw.



Kenny

How did you do this one Carole? Was this on a tracking mount? Is the blurring in the foreground cause by that? As you know my exposures are much shorter but I get similar blurring of foreground when I stack multiple exposures.

Carole

Yes the blurring is due to following the stars so the foreground gets blurred.  Yes it was on my HEQ5.

Carole

MarkS

And there was me thinking it was because you were driving through the campsite at 100mph!

Carole

#4
Mark, using your technical know how, why do you think I didn't get any nebulosity showing on this image.  Was it because the sky was too light/light polluted (as my DSLR with telescope images the following day also produced no nebulosity).  I only got 2 or 3 subs before dawn started to appear, but I moved pitches so I could get Antares about 2 hours earlier the following day, but still didn't get any Nebulosity.

Or is it because I am using a cheap lens? 

Carole

Carole

This is a stack of 2 (one I did earlier) when Antares was still in the trees.  Managed to do a little processing on this, but not much.  The dark rounded thing on the right I don't think is a tree, it must be the telescope it was mounted on as it's in the image on post 1 as well.   I did some flats, but as this data is so poor I haven't bothered to apply them.



Mac

QuoteAnd there was me thinking it was because you were driving through the campsite at 100mph!
:cheesy:

I would always apply processing to the image,
Especially after Nik Szymanek's talk, when he demonstrated the effect with a stack of just four.

Mac.

Kenny


Carole

Thanks Kenny, actually I hadn't realised how many more stars are visible in the stacked version. 

Carole

The Thing

I think it's pretty good Carole, I'd have been very happy with it from Beckenham (if I could have seen any of these stars there!). Looks like several dark nebulae e.g B42, B78, B59 are showing up quite nicely.

BTW You could try subtracting a sky flat next time. Put a diffuser over the lens and a flat off the light polluted sky then subtract in Photoshop. It's a technique I've read about and I'm going to try.

Carole

Thanks Duncan, had to look those dark nebulae up  :cheesy:
I wondered whether it was just wishful thinking that I could see something, so perhaps not.

I think I did take some flats but because I didn't think the results were much cop I didn't bother to use them and I think the one spot on the lens that looks like dust was in fact dew (despite dew heaters).  I might try calibrating the flats if I can find them on the laptop when i get a chance.

Carole