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lepton3
31-03-2012, 09:51 PM
Quite poor seeing this afternoon, but thought I would have a go at Venus with the new Televue 3x Barlow anyhow. And glad I did, because compared to the 2.5x powermate it gives a nice large image scale, with more transmission at UV (I guess there's just less glass).

This image is constructed a bit differently to my last: here I used UV as luminance, with a normal RGB for colour. I had to do quite a bit of filtering because of the poor seeing at UV, so please excuse the numerous artifacts. Native scale, not resized.

Hope you like seeing a Venus for a change.

-Ivan

Lester
31-03-2012, 10:05 PM
Nice view of Venus, Ivan. I cannot tell what the artifacts are. If all those shadings are actual cloud detail then it is a very good image indeed. Thanks for the view.

lepton3
01-04-2012, 08:24 AM
Lester,

The artifacts I was talking about are the small light and dark spots sprinkled about the place (although they are not so visible on the uploaded image, which is heavily JPEG compressed).

The cloud banding is real detail, which only comes up in UV.

Thanks for your comments.

-Ivan

Shiraz
01-04-2012, 05:14 PM
another really good Venus Ivan. Regards Ray

Derek Klepp
01-04-2012, 07:21 PM
Thanks Ivan.Definitely some cloud banding there.

luigi
02-04-2012, 04:00 AM
Beautiful image of Venus, I like it!

lepton3
02-04-2012, 07:28 AM
Thanks Ray, I've been trying to have a regular look at Venus this elongation. Still playing with different colour schemes.



Yes, Derek, the equatorial banding seems to be a regular feature. Along with the brighter northern pole, it's been on all of my images this season.



Thanks Luigi, glad you liked it!

-Ivan

asimov
02-04-2012, 02:43 PM
Some nice detail there Ivan. Just need better seeing. Looks a bit purple/blue in the shadows on my monitor.

lepton3
02-04-2012, 05:05 PM
Thanks John, yes, Venus is the opposite to Mars re seeing (i.e not forgiving at all). All the detail is at UV, and also it's low in the sky and the scope/air temp never stabilizes, so there are all sorts of thermals. I use a cafe umbrella to shade the OTA, but there are still thermals.

Plus this time I dropped the cast iron umbrella stand on my foot, so I was capturing in pain! I don't get that with Mars!

Re the colour, I think using UV as L should give a neutral shadow, but you can see from the background the colour balance is skewed to blue. If the data was slightly better, I'd be motivated to try it with UV as B, but I think there's a limit to how much I want to flog a recalcitrant horse!

-Ivan