NGC6888 in HST palette, SN2009dc and SN2009dd

[paulobao]

Here I'm again,

here my first ever attempt to make a color narrowband image. Since I'm accumulating a lot of narrowband data from the NGC6888 region for my bubble like PN project I took a couple of hours to experiment and making my first color narrowband image. Of course I used NGC6888 as my main target.

I made a HST palette image and a more conventional one (!).

In 2 night I took sometime before collecting the NB data to capture 2 of the most recent discovered supernovas.

I hope you like it a little. I had fun make it.

Regards,

paulo

NGC6888 - 25x20min of Ha data

NGC6888 - 15x30min of OIII data

NGC6888 - 1x20min of SII data

NGC6888 - HST (SII:Ha:OIII)

NGC6888 - "RGB" (Ha:Ha+OIII:OIII)

SN2009dd in UGC10064 discovered 2009/04/09

SN2009dd in NGC4088 discovered 2009/04/13

[narrowbandpaul]

paulo, I too have recently done a narrowband crescent. The sulphur is exceptionally weak for this target, as I think you discovered!

the O[iII] component is not bad.

Its a very good image, and will be fantastic once you have the data you want....

good luck

paul

[moocher]

Excellent work!!!! Another Supernova!!!!!!

Alan:)

[Tim]

oooooooo! I like the RGB version especially Paulo, especially nice to see that bluish outer envelope in evidence.

Cheers

TJ

[Aza]

I really like the 'RGB' version!

[narrowbandpaul]

paulo, a similar pallette that also works well is Ha;OIII; OIII+0.3*Ha, the last one mimicks Hbeta nicely. The resultsb are similar to the above.

I also tried an Ha03O3 and found this worked best when the sulphur was weak....

paul

[Doc]

I like the mono versions. I have a thing about black and white photography.

This is awesome work Paulo amazing what difference the added O111 data makes.

[paulobao]

Thanks for all your comments and for the tips. I will try those mixs too, but I need more data, specially the OIII. I find I challenge to get this data here. I have horrible gradient when I take the OIII frames. No problems with Ha and SII !

Lots to learn.

Regards,

paulo

[Aza]

What OIII filter do you use. From what I have been reading the 3nm is best for OIII.

I have a set of Astronomik narrowband filters, for when I eventually get a mono cam.

But I think I will be tempted to get the following Astrodon filters for best results:

Ha 5nm

SII 5nm

OIII 3nm

[narrowbandpaul]

personally we (douglas and I) use Astrodon 13nm filter. Remember that the O[iII] line is a doublet, at 497 and 501nm, thus a tight filter will only include one line (500.7) since the lower energy emission is most probable.

3nm however is perfectly good.

The same applies with S[iI]

You do infact get a better SNR with a tight filter like 3nm, not by allowing thorugh more signal, but by blocking out more background. This really helps during midsummer when the sky is dark blue, or when the moon is around.

I think you would get some fantastic results with those choices of filter.

I would also add that if you are thinking of astrodon, also consider Custom Scientific 5nm?

They are rumoured to be better quality than astrodon, perhaps with regard to substrate parallelism and IR blocking.

Either astrodon or cust sci should give excellent results.

paul

[Aza]

When I eventually get to start my narrowband imaging, I will try the filters I have, I think they are all 12nm, and see what the results are.

But of course I would hope to get the best possible images, and that may mean upgrading the filters....shame they are so expensive

[narrowbandpaul]

they get ridiculous when you get 2"....

[MartinB]

Great work Paolo. You have enough clear skies where you are to do some great narrow band work with that camera. I think you might need to shift the ratios round a bit to get the SII and OIII to do there work. The RGB works best for me with this image. The Ha detail is stunning. Are you using any antiblooming software? I've tried the Maxim debloomer which isn't bad. Ron Wodaskis plug in is a bit better but the best I've tried is CCDstack

Arran, I think you are right to see how you get on with the Astronomik especially with your F5 scope, I think you'll be very pleasantly surprised. A 3mm OIII Astrodon my be great with an F8 RC but I don't think it will perform well at F5 because the band pass will be shifted

[Aza]

Thanks Martin. Probably saved me a lot of money there!

The places I have been reading up, are indeed using high end scopes, which is probably why they are talking about those filters