NGC 6960 Veil Nebula

[Guest]

I made an attempt at the Veil Nebula last night and learned a few more things about imaging - like how soul destroying it is when you've taken an hours worth of data and then have to flip the scope over as the target has moved so far that the camera's are touching the pier I lost 40min of data but in the end was able to get a total of 120min in 6 20min exposures. No flats/darks/bias.

Many of he examples of this object I've seen are blue and red instead of green in red - however, looking at images taken with the QHY8 most are green and red. This camera is not so sensitive to blue but in other images I took it's not far off the green and red - but in this one the blue channel was almost non existent, which can be down to the target or atmosphere I suppose - it was a bit hazy? Anyway it seems on a par with what others have achieved so I'm pretty happy - and it's going to be clear again tonight

[Ant]

I've not seen colours like that before on the veil - your's is looking quite browny in colour.

Quite nice though Using flats and bias frames will really help though.

Shame about the loss of the subs - we get so few clear night, it really goes against the grain to waste them doesn't it!

Cheers

Ant

[Guest]

I've not seen colours like that before on the veil - your's is looking quite browny in colour.....Ant

I agree - I had always seen this presented as blue and red but I googled QHY8 and Veil Nebula and quite a few get the same result surprisingly.

I found the missing blue though by using Colors In Motion in Nebulosity (see below) now I just need to turn it black har har! The picture on the right is how the one above started out before i started processing - which of course is part of the problem to - I don't know what I'm doing.....

One thing to note is that I left the red light on in the obby on one of the exposures - didn't appear to be any different than the others but I wonder...

Thanks for the feadback Ant

David

[Guest]

I've since discovered a few (two) things about my image :-)

1. It's not the Veil Nebula - it's the Witches Broom - whoops!

2. The colours are a result of using the QHY8 one shot colour camera (OSC) - you get what you get in the pixel range as there aren't any filters etc - an example was pointed out here:

Reflection & Emission Nebulae - Craig & Tammy Temple | SmugMug

Amazing shot

I'm now imaging the "real" veil nebula NGC 6992 which should turn out green and red again - I hope - otherwise I'll be completely confused har har

David

[NickK]

Pesky GOTO

Looking good!

[JimStan]

The "witch's broom" is just part of the "Veil" nebula, which actually has three distinct parts, the part you photographed, with the star in the middle, a more circular side with no real forground star, and a roughly triangular shape that extends somewhat down between the left and right side of the circle formed by the two brighter parts.

All three parts are a result of a super-nova explosion that took place back in much earlier times. Centuries ago, this would probably have resembled the "ring nebula" in Lyra, but it has dissipated to a great extent since it first formed.

Jim S.

[Guest]

Further to my post above I've discovered that if I stack the subs in Deep Sky Stacker they come out in the more common blue red format. Just need to determine what setting I'm getting wrong in Nebulosity (just stacking using drizzle at the moment)

Interesting to see the difference - especially since many others have got that browny affect as seen in mine previously.

The image below hasn't been processed much - I just did it quickly to test.

[Guest]

Further to my post above I've discovered that if I stack the subs in Deep Sky Stacker they come out in the more common blue red format. Just need to determine what setting I'm getting wrong in Nebulosity (just stacking using drizzle at the moment)

Interesting to see the difference - especially since many others have got that browny affect as seen in mine previously.

The image below hasn't been processed much - I just did it quickly to test.

I've discovered that the colour defect occurs when I use the DDP (Digital Development Process) in Nebulosity 2. If I stack the images in Nebulosity2 and apply DPP it produces the green/red format of my earlier images. If I stack the images in Deep Sky Stacker then open the FIT in Nebulosity and apply DPP it produces the normal blue/red format. So, I guessed that the error occurs when you've debayered the images in Nebulosity instead of DSS - my test demonstrated this was correct - if I debayered the stacked image in Nebulosity2 instead of a batch debayer prior to stacking I could pull out the blue/red format. So there must be a setting in Nebulosity2 that I've got wrong :-) I've tried a few in preferences but no luck. The search goes on :-) Now - to re-process ALL the images I've taken to date - although the Veil and Witches Broom is the only images this error has occurred on.

David

[ollypenrice]

The ring nebula is a planetary nebula, not a supernova remnant. I can't see any connection to be honest?

I think that in natural colour the blue/red is right. The shock front is ionizing the hydrogen on the inside of the system and the reflection, outside, shows blue. Seems right to me. Lots of QHY one shot colour images seem to be green and brown but I have no idea why. I'm sure it's wrong but must be easily adjustable.

I don't understand the problem with the flip. You shoot one set on one side of the mount then a second set, 'upside down,' on the other. You can still combine them. This is quite routine in DS imaging even if it is a pest! Don't throw anything away!!!!

Olly

[Guest]

[quote Seems right to me. Lots of QHY one shot colour images seem to be green and brown but I have no idea why. I'm sure it's wrong but must be easily adjustable.

Olly

Hi Olly

I think the problem lies in a simple setting in Nebulosity2 - as discussed above - any ideas? Do you use nebulosity2?

David

[JimStan]

The ring nebula is a planetary nebula, not a supernova remnant. I can't see any connection to be honest?

Olly

Sorry, Olly, I was not trying to compare one directly to the other, except to indicate that the other would probably resemble the one if one were to jump backwards or forwards a few billion years or so !

Is that confusing enough ?

I guess that the ring was formed by a much less violent "puff" than the Veil . Then there is the "Gum" nebula ! I don't see too many trying to get pictures of that object. Must be too far south for us northern hemisphere dwellers to see.

Clear skies, Olly

[Vega]

... like how soul destroying it is when you've taken an hours worth of data and then have to flip the scope over as the target has moved so far that the camera's are touching the pier

I solved this problem by premeturely 'flipping' my mount from the beginning so that the counterweights are already on the Western side of the mount. As long as the target is reasonably near the meridian (even when its still East of the meridian), the scope should be able to reach the target without a collision. Obviously you cant use the GOTO function to find your target but thats easily solved by setting the hand controller to display current location and then slew the mount in RA and DEC manually until it matches the target's co-ordinates. Then you can just leave it tracking right through the meridian and on in to the Western sky ;-). With a plug timer as well Its allowed me to do un-attended all nighters

Matt