Canon DSLR: flaming nebula IC405 with 12nm H-alpha bandwith

[Christoph Puetz]

Dear PI Users,

here is another feed for the DSLR Users.

6"/1100mm Starfire APO refractor with 0.8x Reducer/Flattener.

Canon EOS 450d, modified
70 exposures x 210 sec, 1600 ASA and Astronomik 12nm H-alpha Filter clip filter system-
-> 4 hours exposure time.

20 Darkframes

The images was processed as a "real" color image with full RGB debayering (not only the R channel).
HDR Medium Transformation helped to reduce noise and enhance some details.

Maybe I will add full colour frames later ..... to get a ha-RGB image.

Any feedback is welcome.

http://www.ccdsky.eu/Astronomy/slides/f-ic405_h-alpha.html
or
http://www.flickr.com/photos/cpfoto1964/6334214491/in/pool-387956@N23/
(with astrometry results.

[Lex]

Christophe,

So this is just Ha Data? The picture is a bit dark IMO and the stars come out with a red touch..
So if it is only Ha this would explain it...

[Christoph Puetz]

Hi Lex,

yes - it is indeed only H-alpha light, processed like a regular image. I wondered myself, that this could look
this way. You are right, it is a bit dark - but it supresses some chromatic noise as the "green and blue pixels"
in the Bayer Matrix are not "used" (??).
Maybe I could try to switch the Canon into "Gray Mode" and see how this would affect something.

I saw in your appendix that you observe near Luxembourg ? Well this is just near my observation site !!!

Please have a look at this site :
http://www.sternwarte-peterberg.de/sternwarte/koordinaten.html

Astronomically speaking  - this is "just around the corner" !!! 
So if you are interested in a visit - you are invited, we sometimes have visitors from Luxembourg.

[Lex]

Hi,

Yes indeed switching the canon to mono could help, there could be some hidden metadata telling that it is color version.. So PI would recognize it as greytone image?

I already noticed your site lies only a Katzensprung weit weg 

Why not, i would be glad to come over for a visit and exchange some astro tipps 

[Alejandro Tombolini]

The picture is a bit dark

Hi,

It may be an issue regarding connection. I tried the same monitor using the VGA connection and is less detailed and darker to DVI connection. Attached two screen shots.
In DVI connection I can see traces of nebulosity that are completely lost with VGA

Saludos. Alejandro.

[pfile]

Maybe I could try to switch the Canon into "Gray Mode" and see how this would affect something.

i don't know if this is a good idea. the camera might try to compute the luminance of the image and mix in low-SNR blue and green pixels with your high-SNR red pixels.

also i don't know if you can calibrate a canon grey image because if it is debayered and processed in the camera, the original raw data is destroyed...