First UV Venus - I think with clouds! 15-03-2020

[ArmyAirForce]

I think........I've done it. Seeing the nice blue sky late afternoon, and seeing the forecast for overcast imminently, I dashed out, popped open the observatory roof and set up my new IR/UV filter tray in the Skywatcher. After a couple of camera connection problems down to the cable, I started my first IR capture on Venus. 

10,000 Infra-Red frames were captured at 136fps, then I switched to UV, re-focused, slowed down the exposure until the histogram looked ok and began capturing at a maximum of 12fps, even with  very small region of interest. Despite my camera being the ASI120MM-S version, my laptop only has USB2 ports, so this limits the frame rate. From the first IR capture to overcast, was only 11 minutes; so very little time for the UV focus and exposure adjustment. Everything was a little rushed.

During capture in UV, I could see a darker area in the lower part of the phase and another smaller dark area in the upper part of the phase, both near the terminator. While subtle, there definitely appears to be cloud detail there. Checking the forums, I haven't seen any other Venus images or sketches from the 15th for comparison and confirmation.

On the live camera feed, I could see a notable variation in tone across the phase from the UV filter, compared to the even tone of the IR filter. I'm convinced it was cloud structure, even if my processing hasn't done it justice just yet. Very early days learning to use this CaK 395nm ( UV ) filter, but a promising start.

 

[CraigT82]

Yes I can definitely see some features in the UV there, nice one. Focusing in UV is really rough so to do it and capture in just a few minutes so no mean feat! 

[Pete Presland]

Does look like some subtle detail, well done on your 1st capture! 

Which scope was it with, did you use a Barlow?

[ArmyAirForce]

It was the Skywatcher 200PDS with TAL x2 barlow. I didn't have time to try the Televue x3.

[orion25]

Def some detail there. Nice work!

Cheers!

Reggie