Rosette take 3

[orly_andico]

My 3rd attempt to get the Rosette.

I can only start imaging around 1:30 a.m. to 2:00 a.m. when it clears the balcony roof. Unfortunately at that time it's only about 40-50 degrees above the horizon.

I have been using 10-minute subs over the past week or two, but been having so many dust problems on my camera. This is the best I've gotten so far, 3x 15-minute subs, one-shot color, through an IDAS LPS-V4 filter, QHY8 guided with Meade DSI, William-Optics Zenithstar 70ED + 0.8X FR/FF, AP600E QMD.



Obviously (much) more data is required. This is a crop, the full image has dust bunnies in the corner. I need pec pads.

[Gary]

Nice shot! Thanks for sharing!

[cataclysm]

Good effort Orly, difficult object to image under our polluted sky. The LPS-V4 looks like a strong filter, but why is it green bias? Just curious.

[orly_andico]

green bias due to my inexpert fumbling with DSS. yup the LPS-V4 is a very strong filter, it only passes O-III and H-a. With addition of a deep red (Kenko R1) filter it turns into a budget H-a filter (19nm bandpass, not too shabby).

am wondering if one can buy a Kenko R1 filter in 48mm filter size though, its a rare size for camera lenses.

taking more subs now... my guide scope hasn't cleared the roof yet (but the main tube has) so going unguided. 180 seconds is the most i can go for (at 240 seconds unguided i have to throw some subs away).

[orly_andico]

added another 70 minutes (8x3 min unguided, 3x2 min guided - dropped a zero! and 2x20 min guided)

removed the gradient from the final stack using the free Olympus Background Subtraction Toolkit (no it does not do FITS)

[Airconvent]

The final product looks great Orly. It looks more like the Rafflesia flower though. can't understand why they call it the Rosetta Nebula. haha

[jimmyleong]

nice shot... why do you need to convert or change the photo from original green to black and white?