Venus on 15th April 2020

Venus is very prominent in the twilight sky. Its showing a 37.4% disc and this will decrease in the next few weeks but it will maintain its brightness as it moves closer to the Earth in its orbit.

 

It is currently 30.94 arcseconds in diameter - about 1/60th of the diameter of the Moon.

 

Elongation from Sun = 43.9% E

Light time = 4.5 minutes

Altitude = 21 degrees.

 

This was taken using an Infrared filter for Red and UV filter for blue. A 50/50 blend of the two was mapped to green to form a colour (RGB) image.

 

10 x 1 minute video captures (IR 685 nm) at 124 fps for red (stacked into 1 image)

4 x 2 minute video captures (UV 350 nm) at 12 fps for blue (stacked into 1 image).

 

Celestron 8SE SCT scope 2000mm f/10

Baader modular Barlow magnifying lens at x 1.75 plus other elements of optical train (ie, flip mirror and filter wheel) = total focal length of 4500mm f/22

ZWO ASI 290 MM CMOS camera

NEQ 6 Pro mount

Laptop with FireCapture 2.6 acquisition/control software.

 

Settings for IR capture were:

 

Camera=ZWO ASI290MM

Filter=IR685

Profile=Venus

Diameter=30.95"

Magnitude=-4.48

FocalLength=4550mm

Resolution=0.13"

Frames captured=7496

ROI=712x714

FPS (avg.)=124

Shutter=0.324ms

Gain=351 (58%)

Gamma=50

Histogram=69%

Limit=60 Seconds

Sensor temperature=17.5°C

Focuser position=3956

 

Settings for UV capture were:

 

Camera=ZWO ASI290MM

Filter=UV

Profile=Venus

Diameter=30.95"

Magnitude=-4.48

FocalLength=4800mm

Resolution=0.12"

Frames captured=1507

ROI=712x714

ROI(Offset)=449x98

FPS (avg.)=12

Shutter=79.71ms

Gain=351 (58%)

Gamma=50

Histogram=67%

Limit=120 Seconds

Sensor temperature=14.8°C

Focuser position=4808

Done