The Rosette

[roundycat]

Hi all,

it was clear last night from dusk to nearly midnight so I made the most of it in spite of the gusty wind. 150m of G and B to go with the 120m of Ha I took last year. This was with the Artemis 11002 and FSQ so has been severely cropped as the main picture is to form part of a mosaic. A rash of cyan stars owing to the Ha GB combination. I took some R as well so it may be that needs to go into the mix to even up the star size through the channels. Ha in 10m subs and G and B in 8m.

Dennis

[Beyond_Vision]

A great rose Dennis with some good detail just needs the star colour to be tweaked as you have said

Regards

Kevin

[barkis]

It's a corker of an Image,

It looks perfect to me, but you are going to do some more work on it.

Ron.

[centroid]

A very nice widefield, of the Rosette Dennis.

Dave

[MartinB]

It's a magical rosette Dennis and the colour in the Rosette is gorgeous but like you say, the Ha isn't delivering enough signal for the stars

[Whippy]

Very nice Dennis, bit more playing around with those stars and it'll be top drawer.

Tony..

[roundycat]

ok, here is version 2 with the stars sorted out by my new secret method. I sorted the theory behind this whilst in bed and behold!, it worked. What do you think? There are still some halos to sort out but this is only really a half-way house.

Dennis

[FLO]

Whatever you did has certainly worked

[MartinB]

So what is the secret method Dennis Let me guess...did you apply a maximum filter to the Ha stars???

[thing]

That's a gorgeous Rosette Dennis, lovely widefield. The second one is certainly an improvement star wise.

[roundycat]

Hi Martin, if only it were that simple. I am going to write up what I did, do you think it will be worthy of anyone's interest?

Dennis

[ollypenrice]

Lovely. The wind didn't get to your mount, obviously! Mk2 stars are great - well done. I think a bit of full red would help the sky background which strikes me as a tad black, maybe? I find undiluted Ha as red flattens things a bit, too, though the effect can be positive.

We are all looking forward to the mosaic, I'm sure.

Olly.

[RichieJarvis]

That is georgeous - lovely image - your star method definitely deserves a right-up, its done wonders there!

[Beyond_Vision]

Looking much better Dennis

Regards

Kevin

[MartinB]

Hi Martin, if only it were that simple. I am going to write up what I did, do you think it will be worthy of anyone's interest?

Dennis

Well it will have my interest Dennis!. I only ever did an HaHaGB once, that was enought to persuade me that I needed a seperate red channel so I'm up for a neat routine

[roundycat]

I have finished the worked example showing a method of controlling star colour when mixing Ha with G and B, it can be seen here http://www.dens-astropics.org.uk/page%2017.htm.

Perhaps if people find it useful it could be signposted elsewhere.

Dennis

[MartinB]

Thanks for that Dennis. I will have a look in more detail using a pacman image from Kelling. I have tried lots of ways of combining a red Ha channel with RGB and the problems are exactly as you say. Although I don't think the problem is insurmountable. My concern about just getting a few minutes red would be a loss of rich yellow stars.

I'll let you know how I get on and post a comparison of different methods. I will have to do a special red combine with fewer subs.

[Stephen Green]

Brilliant images Dennis no 2 is really great

Stephen

[roundycat]

Martin, I look forward to seeing your results. The star colour in my second version above is nowhere near perfect but is a lot better than cyan everywhere. I think the yellow star problem you mention might not be a problem because of the overall brightness/size of the combination of HA+R. I sit here with bated breath...........

Dennis