A consideration on the observation of Uranus by S.Maksymowicz

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A consideration on the observation of Uranus by S.Maksymowicz

A consideration on the observation of Uranus by S.Maksymowicz
Considering Mr de Greporio results,the last data issued on the alpo site, Something is appearing on the pictures, 
even RGB one at the polar cap.This is not thick indeed, but it is. 
A certain logic can be sustained: contrasts on B channel is very low, quasi-null on the G, the more contrasty, 
relatively on the R. The analogy with visual observation is poor with such. R and G channels are handicaping.
Using a yellow filter visually help to enhance the contrasts essentially due to the 619nm methane ray which is active 
and quite different to the NIR results centered on the 845nm methane ray.
Each methane ray is interresting different atmospheric layer depth. HST results showed this very well.
619nm is accessible to human eye, deep orange color, Under an active sensitivity still.
May I suggest personnally some Imaging procedure using a monochrome ccd chipset with band pass filters use.
Filters only centered on the methane rays of interest, but avoiding deeply the uv, deep blue, the G, nir for some:
- for 619nm: the astronomik R or similar
- for 845nm: the astronomik 742 or may be 807, the cut-off will be insured by the ccd chipset.
for the amateur abilities of to-day.Indeed a proposition only.
All the above aims to reveal or infirm the presence of a dark polar cap with a ring bordering it, 
which are features not thick at the eyepiece (less than the banding pattern).
This is also a strong challenge also for imagers.
Anyway, apart those considerations, the presence or not of the polar cap involves some consequences 
on the uranus atmosphere model not very well established.
These are what I would like to answer in order to may be initiate Something with the alpo Body.
I know using only a narrow bandpass filter will increase the exposure times 
but the proposed practice seems to me a necessary condition for going further.

Images of uranus by HST at 8th-9th nov 2014

ALPOの最新版に掲載されたMr. Gregorioの画像を見れば極冠のRGBにて特徴が見て取れる。(天王星の画像 2018/10/17(UT)を指している)

[Stanislas Maksymowicz  Ecquevilly,France]

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