My first narrowband - Bubble

[vincentnm]

Hi All,

My first narrowband. Tried out the h-alpha filter bought from Peter Shah.

Captured on my 25th Oct 2009.

Scope: C8 with Hyperstar3

Camera: SXVF M8C

Filter: Astronomik H alpha 12nm

Guiding: ST80 with DFK

Mount: EQ6 Pro

10 minutes X 39 subs

Calibrated and Stacked in DSS

Stretched and Sharpened in Photoshop CS3

The camera's a single shot colour. Converted the image to B/W in CS3 after the initial couple of magic curves, and then worked on the mono image to increase contrast and sharpen.

Comments and advice welcome please.

Thanks,

Vincent.

[Dave Moulton]

You have a tasty result there Vincent. Well done to you, a very good efffort in obtaining such detail

Dave

[skye at night]

Interesting to see how a one shot colour ccd deals with Narrowband filters...

Any plans to try OIII etc..

[vincentnm]

Thanks guys.

Yes indeed, I want to try OIII and SII when I get them . On the lookout for used ones, see my advert in wanted.

Thanks

Vincent.

[Taff]

Hi Vincent' nice details in your capture.Mark

[saturn5]

Cracking result,lovely detail.

[ncjunk]

Good image, did you bin the OSC? I have heard that binning effectively turns it into a....ahh losing my descriptive powers...gives a mono picture which, whilst not as sensitive as a true mono camera, provides an average of the RGB pixel values to produce the picture all be it smaller...

its too early sorry...someone hopefully understands my babbling..

Neil C

[SteveL]

Good image, did you bin the OSC? I have heard that binning effectively turns it into a....ahh losing my descriptive powers...gives a mono picture which, whilst not as sensitive as a true mono camera, provides an average of the RGB pixel values to produce the picture all be it smaller...

its too early sorry...someone hopefully understands my babbling..

Neil C

Binning will remove the RGB bayer mask over the 2x2 pixel group. This is useful for taking luminance images, but less so for taking narrowband. The reason is that unlike a mono camera, binning 2x2 with a OSC CCD is still only going to be using the 1 red pixel out of the 4 for Ha, so you dont gain anything more than if you imaged 1x1 (normal) and stripped out the red channel to stack. OIII is slightly different, as it can show up in both the blue pixel and the two green pixels (its a greeny-blue), and depends on the exact colour response of the OSC.

[vincentnm]

Thanks Guys.

Neil, Steve,

Yes, I did try binning as well, but not in the image posted above. Captured unbinned, but tried binning while debayering. I used the "Super Pixel Interpolation" debayering feature in DSS (Options->Settings->Raw/FITS DDp Settings->Fits Files Tab).

"This option uses the bayer matrix to create one super-pixel from each group of 4 pixels (RGBG)"

Made a marginal difference. As Steve said, the B and G filters in the bayer matrix gives less signal in the B, G, G pixels while using an Ha filter. Here's the "Super Pixel Interpolated" version.

[JCJC]

Great detail Vincent, the second is showing a bit more faint stuff I think.

Jordan

[Milliways]

Great image mate, i really wanna get into narrowband imaging. well done