Contains:  Solar system body or event
Venus in true and false colours - 21st November 2024, Niall MacNeill

Venus in true and false colours - 21st November 2024

Venus in true and false colours - 21st November 2024, Niall MacNeill

Venus in true and false colours - 21st November 2024

Equipment

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Acquisition details

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Description

Well if Jupiter is no good for us Southern Hemispherers, I might as well have a go at Venus which is well placed for us now. 

I put together this collage from a number of filter combinations from a single evening's imaging. The seeing was decent given the planet's good altitude.

The first image (top left) is a colour one (RGB). Despite Venus being reported as featureless in visible light, I have rarely found that to be so. When we see it through the eyepiece it is so bright, that any colour is washed out, but the camera and filters do a good job of showing the subtle hues across the planet's cloud tops and there is to my eye a correlation with the UV and IR images. This was captured with the ZWO ASI 178MM camera.

The top right image is the straight UV, which as usual shows the most detail and structure. I colourised it violet/ purple for aesthetic reasons. This was also captured with the ZWO ASI 178MM camera, whihc is has outstanding UV sensitivity.

On the other hand I used my QHY5III200, which has excellent sensitivity in IR to image at both IR 850nm BP and also using my Methane Band filter, 889nm with a Bandwidth (BW) of 18nm. Some subtle features were visible with both these filters and what's nice is that I could see that they corresponded pretty well. I slightly prefer the Methane band image and the reason that I use it is because all wide band filters suffer from an amount of atmospheric dispersion at low altitudes. The narrowband of the Methane Band filter avoids that and there is plenty of light to get an image. 

The third image (bottom left) is an IR(G)UV image where the IR(CH4) is set to Red, a 50:50 IR:UV blend is set to Green and the UV is set to Blue. These false colour images have their own beauty and display a lot of information in a single image.

Finally my Wratten#47 Violet filter shows some nice structure like the UV, so I used it to produce a B(V)UV false colour image where the Blue is set to Red, the Violet to Green and again the UV to Blue. This is what I call a false colour, spectrum shifted image, where instead of RGB, as our eyes can see, we have BVUV, as perhaps the Venusians see . This is of course the bottom right hand image.

I hope you enjoy these various views of our hellish twin planet.

The individual image are shown as revisions in case you want a closer look.

Comments

Revisions

  • Final
    Venus in true and false colours - 21st November 2024, Niall MacNeill
    Original
  • Venus in true and false colours - 21st November 2024, Niall MacNeill
    B
  • Venus in true and false colours - 21st November 2024, Niall MacNeill
    C
  • Venus in true and false colours - 21st November 2024, Niall MacNeill
    D
  • Venus in true and false colours - 21st November 2024, Niall MacNeill
    E

B

Description: RGB image

Uploaded: ...

C

Description: UV image...colourised for aesthetic purposes

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D

Description: IR(G)UV image.....false colour
IR(CH4) as Red
50:50 IR:UV as Green
UV as Blue

Uploaded: ...

E

Description: B(V)UV image.....false colour
Blue as Red
Violet as Green
UV as Blue

Uploaded: ...

Histogram

Venus in true and false colours - 21st November 2024, Niall MacNeill