Eastern Veil Nebula, NGC6922

[The Thing]

Image date, time and location:    4 August 2013, 00:00-02:30, Beckenham, Kent, UK
Telescope aperture and focal ratio:    Meade LX90 8" UHTC f10, Baader Alan Gee Telecompressor (f5), HEQ5, OAG with QHY5 and PHD 2.0.5 alpha
Camera and filters used:            Canon 1000D Modded, Astronomik CLS-CCD
Processing applied:                    Deep Sky Stacker and minor tweaks in Irfanview, no sharpening

Also used Astrotortilla to verify polar alignment and to find the target easily, SkyChart (Cartes du Ciel), EQMOD, AstroPhotography Tool 2.25" (Beta).

21 x300s @800ISO subs


Larger version (half original size)

[JohnP]

Looking good Dunc. What length were subs. A few stars looks like marginally elongated/ tear drop shaped but other than that I really like it - nicely framed & good colours...

John.

[The Thing]

Looking good Dunc. What length were subs. A few stars looks like marginally elongated/ tear drop shaped but other than that I really like it - nicely framed & good colours...

John.

21 x300s @800ISO subs, should have put that in the post.

Thanks John, some more attentive processing would help as well I am going to have another go using IRIS rather than DSS. In IRIS I was getting a problem with the second sub after RGB conversion doing Stellar Registration. It was odd 'cos I tried duplicating the first RGB1.PIC to replace it and got the same error with RGB2 even though IRIS processed it as RGB1. And it happened on the desktop and the laptop. Wierd.

There are two things going on with the stars. One is the Baader Telecompressor which is a reducer/flattener and is incredibly sensitive to spacing, I think even changing focus slightly to cope with temperature fluctuations makes a difference (SCT mirror moves- distances change). The other is RA and DEC guiding accuracy, my RA RMS value was twice the DEC value last night, hence the slightly elongated stars. On the plus side everything else is good enough for it to show!

[MarkS]

Lovely image - one of your best and definitely very impressive for Beckenham!

Still can't believe you could see the Andromeda Galaxy naked eye - it must have been quite an extraordinary night.

Mark

[Carole]

Very impressive from Beckenham,

[The Thing]

It was very transparent, I could see stars I only see at DSCs, and I've never seen a meteor from Beckenham before.

[mickw]

That's looking good Duncan and nice detail

I don't think DSS is doing it justice though

[The Thing]

Thanks Mark, Carole and Mick. Reprocessing in IRIS right now...

[Fay]

Very nice Duncan, you did well

Fay

[The Thing]

Now 42subs most 5 mins but 9x 7mins as well.
All else as before. The stars could be better, but at least they have some colour.

Full size (bin 2)

[MarkS]

Excellent colours - the nebulosity has come out well.

As you said, the stars are slightly iffy - with distortion near the image corners and extended "redness".  However it is only really noticeable on the larger image.  Has the red channel been scaled up a lot?

An excellent image for Beckenham!

Mark

[Carole]

That whispy blue nebulosity especially bottom right is difficult to get even from a dark site, so you did really well Duncan.

Carole

[mickw]

Really good Duncan and nebulosity is great

[Mike]

Great image Duncan.

[The Thing]

Excellent colours - the nebulosity has come out well.

As you said, the stars are slightly iffy - with distortion near the image corners and extended "redness".  However it is only really noticeable on the larger image.  Has the red channel been scaled up a lot?

An excellent image for Beckenham!

Mark

I used your processing script followed by a mask and SUBSKY3 to remove gradients then asinh as per your note. Then BIN 2 and MULT 0.25. I've not done any colour changes. The Mask seems to have revealed extra gas... or its made it up!