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Venus Image 2015/08/15(UT)
Ferenczi Imre,Pete Lawrence,Peter Edwards
Ferenczi,P.Lawrence,P.Edwards
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Ferenczi Imre(127mm refractor) |
2015-08-15 9:50 - 10:10 UT
2015-08-15 10:26:14 UT
2015-08-15 9:52 - 9:57 UT
[Ferenczi Imre,Budapest - Magyarorszag Hungary]
After a few rather dodgy days in terms of the weather, today (15 Aug) gave me clear skies to catch the moment of inferior conjunction.
A number of comments have been made about the lack of cusp extensions visible in images taken of Venus (mine and others).
After posting I had to head off to give a talk so further processing had to be put aside.
The capture of the 'pretty' conjunction image sent out yesterday was followed immediately with another sequence designed
to push the exposure saturation closer to 100%.
This is tricky to do with a thin Venusian crescent in a bright sky as variations in solar seeing tend to produce 'hot-spots'
on the crescent where the atmosphere appears to focus parts of the crescent better than others.
Consequently, imaging close to saturation can easily result in the crescent over-saturating.
In the attached image, the background has been left untouched. Being a bright sky and close to the Sun,
every blob of dust in the system becomes very evident - much more so when stretching the levels.
However, leaving things au natural does allows the cusp extensions to be seen. In this result they have been measured at
206 degrees which is fractionally less than my last measurement.
The decrease is most likely due to human error in measuring the end of the cusps and the quality of the atmospheric seeing.
I have other results from yesterday which I will analyse in due course, but the 'missing' cusp extensions were definitely there!
[Pete Lawrence: United Kingdom]
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Peter Edwards(C14 355mm SC) |
Managed to get a shot of Venus between the clouds today.
No sign of extended cusps however.
[Peter Edwars: West Sussex United Kingdom]
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