Hi all,
this is my latest professional work. It Messier 74 imaged with the 3.5 meter telescope of the Calar Alto Observatory. The data was adquired by Vicent Martinez and Alberto Fernandez in a night of poor seeing (1.8"). As this seeing didn't permit to do science, this was an improvised image.
I had not a large amount of data to process: only one 5 min. exposure with a red filter and 2x5 min. exposures with two other narrower filters... I think this would be comparable to a 4 hour exposure taken with a 20" telescope.
These are the filters:
- Sloan r' with a transmission range of 550 to 700 nm.
- 30 nm. filter centered at 520 nm., centered in a part of the spectrum without any emission lines.
- 30 nm. filter centered at 489 nm., wich includes the O-III and H-beta emissions.
Obtaining a "real" color image from this filters have not been an easy work... :wink:
The image has been reduced from 4K to 1400 pixels, because in the original the stars are 8 pixels wide. Image scale is 0.58"/pixel.
This is the image:
Regards,
Vicent.
