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Old 08-12-2013, 04:42 PM
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Sebbie (Sebastian)
Sebbie

Sebbie is offline
 
Join Date: Jul 2012
Location: Canberra, Australia
Posts: 260
Thanks for words of appreciation Pat, Rolph and Geoff!

Yes I haven't had that many sessions this year partly because of work commitments, overseas travel and (most of all) pretty average seeing conditions at my southerly latitude.

Here's something else that I'd love to share (because I had so much fun with it but ultimately did not succeed ) - an attempt at Venusian cloud imaging through a colour filter. Used #58 Green (24% transmission) photo visual filter, part of the standard Meade series 4000 set. The advertising brochure states: "Use on telescopes 8" aperture and larger to reject blue and red-toned structures.. increases contrast of atmospheric phenomena on Venus."

Below pic was captured at f30 approx. 45 minutes before sunset. 3 minute long avi had 1241 frames over 70% quality stacked in AS!2 and post processed in Registax, ACDsee and Astra Image.

I got very excited originally when I fiddled with hue, saturation and colour balance ACDSee settings.. all of a sudden wavy patterns appeared on the planetary disk (middle image). They were persistent irrespective of how many frames were combined and AS!2 align point location. I was sceptical though because of how hard edged these looked.. eventually I varied processing workflow and it seems that ACDSee clarity / noise reduction functions might have been introducing these artefacts following the stack (no trace exists in the right image which had colour adjustments done first).

What does everyone think? Is it possible to image Venusian clouds without the UV filter?

Cheers
- Seb
Attached Thumbnails
Click for full-size image (Final_Anno_AS_f1241_Multi_Venus f30 Filter 13-12-02 19-16-14_g4_b3_ap16.jpg)
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