Saturn 11/04/05

[Comet Hunter]

Managed to get out early and have another go at Saturn, using the 3x Televue barlow for the first time with the Toucam. Time was approx. 6:30pm local, scope had been setup only an hour or so and was still in the process of cooling down however still managed some decent shots. Avi's recorded @ 5fps giving a total of 1800 frames.

I tried two methods of recording settings. The first setting involved setting brightness to 50% and using shutter speed + gain to set the required conditions. It has a little more banding detail then the previous Barlow attempts when using the Quickcam 4000 back on 15/02/05 ...
http://comethunter.com/images/110405sat.jpg

This is a 50% version...
http://comethunter.com/images/110405sat50.jpg

The second method involved setting a low gain (0-15%) and used brightness + shutter speed to acquire the desired conditions.
http://comethunter.com/images/110405satb.jpg

This is the 50% version of method 2..
http://comethunter.com/images/110405satb50.jpg

The high gain version has a lot of blurry blueness around the rings and globe, while the second method shows signs of the 'onion rings' similar to those seen on some Jupiter shots ...

[[1ponders] (Paul)]

Glad to see there's still a few still giving saturn a go before it disappears. Good going for so low in the sky. I see what you mean by the onion rings.

[toetoe (Peter)]

The second method looks better to me Andrew, the detail seems better than the first one. Both good shots tho..

[rumples riot]

I like the first one. Great shot of Saturn, something that has alluded me this season. Well done.

[Mick (Michael)]

Lovely images Andrew, I had a look at Saturn tonight it was steady at 300x, we are lucky it's still high in Qld hey.

[iceman (Mike)]

I too like the 1st one, the banding on the planet is much cleaner, although I see what yuo mean about the blue. It's possibly due to atmospheric refraction..? Did you do an "estimate" RGB shift before applying the wavelets?

You can reduce some of the blue in photoshop or similar but I couldn't get it to go away completely without making the image too yellow.

Is it possible that the red/blue settings were tilted too much towards blue during your capture? Did you do the "auto" and let it auto-adjust for 10 seconds and then turn it off?

Anyway regardless of the blue, that's a great Saturn. One of your best!

[Comet Hunter]

Yeah, the first one shows a tad more banding then any previous shot I've manged. All my images get a run through the RGB estimator My skills at post Regitax manipulation are limited to basically file resizing/cropping

As for the blue, all of my Saturns, particularly the larger scale shots, and the rear of the rings display the foggy blue and I cant say I remember noticing it on shots done by others - It happens with both the the QC and Toucam so that rules out a specific camera issue, leaving either settings/processing or.... the scope as the cause