As promised in my previous Observing Report, here's the final version of the Saturn pic that I made a few days ago:
All I've done is neaten up the edges by applying a mask, bring up the contrast and saturation on the face of the planet by using the burn tool, and desaturate the background. Yes, I know, I've probably overcooked it. I did use a reference picture for the colours in an attempt to keep it looking real.
Last night I managed to sneak out for another attempt at webcamming Saturn with the scope. The seeing was much better, but there was a lot of cloud about which meant that I had to wait for gaps in order to capture data. To get some idea of the improvement in the seeing, here's a 20-second snip from one of the .avi files, in .mp4 format:
These .avi files were taken with revised settings as per the advice of the folk on the SGL Forum, and because of their suggested improvements, this stacked interim image is my best one yet:
I'll finish it off later, when I've more time to learn all about the use of Photoshop layers. Hopefully I can sharpen up the edges and enhance the surface detail without losing more than I gain.
I would have taken more pics and looked at some other celestial gems, but the temperature dropped and all the mirrors dewed-up, so I had to pack away. Never mind, there's plenty of future to look forward to.
Onwards and upwards!
I'll post the settings here for reference:
******** Capture Settings:03 April 2008 / 22:37:32 ********
Program :WcCtrl - WebCam Control Utility (V 1.5.46)
Cam Driver : Philips SPC 900NC PC Camera (0xaf42ab7)
Comment added : a comment
******** Capture Cam Settings:03/04/2008 22:37:32 ********
Set-String :
Brightness : 69%
Contrast : 51%
Saturation : 31%
Gamma : 26%
Color Mode : 255(0=off)
WhiteBalanceM : 4(0=lamp,1=sun,2=FL,3=manual,4=auto)
WhiteBalRed : 51%
WhiteBalBlue : 52%
FPS : 15
NonSC Exposure: 2(0..10=longest to shortest - depends on camera)
Gain : 81%
FlipHorizontal: 0(0=off)
FlipVertical : 0(0=off)
AutoExposure : 0(0=off)
AutoAll : 0(0=off)
-end of setting------------------------------------------------
At about 21:30 the light clouds parted and the stars were bright against a really dark backdrop, so I took advantage of this unpredicted opportunity and set up to get some more experience of webcamming Saturn with the scope. As expected, the seeing was rubbish again (too much air-turbulence caused by rising warm air mixing with the colder stuff higher up), so the images in the acquired .avi files weren't holding shape or focus. To get some idea of the seeing, here's a 15-second snip from one of the .avi files, in .mp4 format:
Anyway, I ended up with 9000+ frames to play with. I plugged the files into K3CCDTools to do a quality analysis, then exported the best 10% + about another 100 that the quality sorter ignored to a folder, manually sorted the best 360 of these in vdub and then stacked 'em in Registax, which didn't crash at all this time! The result's not brilliant, but it's better than previous efforts:
After what seems to be weeks of cloudy sky, last night started reasonably clear, so I nabbed the chance to see what can be done with a webcam attached to the scope.
The webcam of choice is the Philips SPC900NC, which is recommended by every man and his dog because the sensor is a CCD instead of a CMOS, and because it's fairly easy to modify for raw image and/or long-exposure capture (I might get around to modding mine sometime, but for now I'll keep it as is until I get the hang of this imaging malarkey). It's also recommended because it's cheap (currently <£30 from Amazon, even cheaper if you shop around).
It's been removed from the original housing and temporarily rehoused in a cheap plastic box, primarily to allow a T-thread adapter to be fitted in place of the supplied lens. Removing the lens means that the IR-cut capability is removed as well, which has a detrimental effect on image quality, so I'll be sourcing a suitable filter soon. For now, though, it's a case of going with what's available.
The webcam was attached to the Baader Hyperion Zoom eyepiece using a 50mm extension tube to give the required image size on the chip. Setting the BHZ to 12mm gave the best image, but the seeing was absolutely rubbish, nothing was staying in focus and the image was boiling and hopping about all over the field of view.
Still, anything's better than nothing, I needed some practice and some material to work with, so I rattled off a few .avi captures until I'd amassed just over 9,000 frames, then took some dark-frame captures to aid in the stacking process. Shortly afterwards, I had to stop as the skies clouded over again, so I didn't get to look at anything else interesting.
After packing up, I plugged the dark-frame and the best 5% of the .avis into the K3CCDTools stacker and a while later, after much mucking about with settings, parameters, buttons, knobs, dials, gauges and other such software options, it spat out an image not unlike this:
which was crudely Photoshopped (over-exposed, too much gain, many other faults too) to give this:
I'll play about with the acquired .avis later to see if I can drag a better image out of the data.
Yup, the clouds didn't break at all last night or this morning, I didn't see the Moon at all. 🙁
Never mind, there'll be another Total Lunar Eclipse along soon... in December 2010. 😯
