Ok, here's the final result from combining 6 separate runs taken between 4am and 5am on the morning of 28/12.
The image size has been resampled to 150% and I decided to leave the final image at that size.
The brightness and contrast may be a problem, I don't have my trusty CRT on hand to compare with, and I am working on a Dell lcd display so it may need to be tweaked. If you find it too bright or "soft" then let me know.
Details:
13.1" f/5.5 newtonian + TV powermate, FL=11000mm
True Technology filter wheel + Astronomik RGB filters
PGR Dragonfly Express monochrome firewire camera
Captured on Linux with Coriander, processed with ppmcentre on Linux,
Registax, Astra Image and The Gimp under Windows
approx 12 minutes each or red, green, blue
red/green: 20fps, blue: 12fps
Both look quite superb on my LCD monitor. The 2nd one looks a tad too sharp but that would just be nit picking. Wow, what gorgeous images of the ringed one!
It's been sitting here in it's shipping container for a few weeks. Now that the 13.1" is working well I'm in no hurry to use it - I don't have access to any workshop while we're living as guests with Michael & Cate and I have to build a new mirror cell + cooler for it.
It may stay in it's box until we move into the new house in March and I have some space to work. It's going to be a close call whether it fits in my current tube (16" tube, 14.5" mirror...) so I may give in and have Gary make me a larger tube for it... I sort-of plan to buy a larger mount to stick in the observatory when we move in, maybe a Titan?, and maybe one of those yummy 3" JMI motorised focussers...
Here's the separate red, green and blue images. Just look at the difference! The low altitude is mostly to blame, at 39 degrees the blue has a lot of air to go through.
Hi Bird, I like these a lot, especially the sharper second one, though the softer first one looks more natural. The image scale is just ENORM and really smacks you in the face
I'm amazed at just how good your blue channel is in relation to the red, especially at your latitude. Even when I've had reasonable seeing up here the blue is woeful by comparison to what I've got in the red.
Hi Bird, I like these a lot, especially the sharper second one, though the softer first one looks more natural. The image scale is just ENORM and really smacks you in the face
I'm amazed at just how good your blue channel is in relation to the red, especially at your latitude. Even when I've had reasonable seeing up here the blue is woeful by comparison to what I've got in the red.
Impressive
Robert, with a monochrome camera and electronic focusser there is something of an advantage over a colour camera - it's possible to set the focus for each colour channel separately so that each one is focussed as best as possible.
I normally find that the three colours focus at different points, probably a side effect of the glass elements in the powermate or maybe dispersion effects in the atmosphere, not sure.
Anyway, I spend a lot of time checking and tweaking the focus for each channel.
Believe it or not, I'm *still* reprocessing this image... fixed a few bugs in ppmcentre (now called ninox btw), added a couple of new features, process process process...
I'm kinda hoping that I'll be finally done sometime later today, I'm starting to see the registax window in my sleep...
