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Venus 2020/02/01 73% illuminated IR

I want to improve my planetary imaging before October this year when Mars will be very prominent in the night sky.

 

At its furthest, Mars is quite small at about 4 or 5 arcseconds - about a 1/3 of the size of Venus in this image. At opposition, it will be about 22.6".

 

To do it well, I'll have to master automatic filter wheel changes, automated acquisition sequences and planetary guiding.

 

This image of Venus was taken with a Celestron Nexstar 8SE and a TeleVue x 2 Barlow giving a focal length of 4000mm at f20 - more zoomed in than Ive tried before with Venus imaging. Its interesting that the software thinks my focal length is actually 5500mm - could be because there is a long imaging train of focuser, flip mirror box, filter wheel and Barlow attached to the end of the scope! Focusing by moving the primary mirror of an SCT also affects focal length.

 

I set up autorun sequencing in FireCapture 2.6 to take 18 x videos of 5000 frames each (36 seconds to acquire each video at 137 fps), stacked those in AutoStackert!3 (best 5%) and then stacked the 18 images again to produce this 1 image. Luckily, AutoStakkert!3 does batch processing!

 

I managed to get autoguiding running in FireCapture (by using ASCOM to control my mount) but it wasn't as accurate as me doing the guiding manually.

 

Overall, Ive got FireCapture to control my electronic focuser, filter wheel and mount using ASCOM and am getting to grips with planetary guiding and acquisition sequencing.

 

I'd love to see some cloud detail in the Venusian atmosphere so next time will either try a Violet filter (+IR blocker) or a Baader U filter which passes UV light.

 

Equipment and settings:

 

Celestron Nexstar 8SE SCT @ 2032mm focal length and f/10

TeleVue PowerMate x 2

SkyWatcher EQ6 pro mount with Rowan Belt Drives

ZWO ASI290MM monochrome CMOS camera.

IR pass filter @ 742nm

 

Acquisition with FireCapture 2.6

Stacking with AutoStakkert!3

 

ASI290 settings:

Camera=ZWO ASI290MM

Filter=IR742

Profile=Venus

Diameter=15.39"

Magnitude=-4.10

FocalLength=5500mm

Resolution=0.11"

Duration=36.314s

Frames captured=5000

File type=SER

ROI=880x646

FPS (avg.)=137

Shutter=1.323ms

Gain=323 (53%)

Histogram=38%

Limit=5000 Frames

Sensor temperature=16.6°C

Focuser position=865

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Uploaded on February 1, 2020
Taken on February 1, 2020