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Saturn, trying to see more than just 2 belts.

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#1 Kris.

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Posted 16 March 2009 - 05:47 PM

i had moments of rocksteady seeing this evening, even at powers of 400x and 500x with my 8" dob, saturn looked pretty and the small gap between the rings remained visible. altough 250x provided the best view in terms of details on the globe.

seeing more than just the two equatorial belts smeared out has always been a challenge for me, and i wanted to grab the opportunity of the closed rings and steady seeing to try to see more.

in short: i failed. i didn't see more belts. but staring at them showed some subtle details i think i missed out on last time(s).

it's very difficult to reproduce the fine differences in shades, so a little explanation will be handy as the sketch fails to show you what i saw.


(south is up in the sketch, i believe)

- overall, the southern hemisphere was noticeably darkest, and the one belt i could discern there was smaller than the one in the northern hemisphere, but darker.
- whereas the north belt has a more smeared-out appearance at both edges, i think the south one has a distinct sharp edge towards the equator, gradually fading out towards the pole.
- the south pole region has abouth the same darkness than the south belt, and it too seems to fade gradually into that belt.
- the regions around the ring are brightest. about the same to each side.
-then very gradually a broad belt begins to darken which fades again when it starts to reach the north polar region.
- it may have been my eyes playing tricks on me, but the north polar region actually looked very bright, about the same as the region around the ring.

sketch detail:
16/03/09 around 22:30 local time
8" dob @ 250x using 4mm UO Ortho
orange, green and blue filters used. orange didn't help, blue not very handy either, green provided better contrast. i will try this again next time.
the two moons at left are Iapetus (left) and Dione (right). not included in the sketch, but visible were Titan and Rhea.

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#2 Tommy5

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Posted 16 March 2009 - 08:25 PM

Very nice sketch of Saturn,the belts on saturn are much less prominent then the bands on Jupiter, a haze layer covers the top of the atmosphere, i would try somewhat less mag to get more contrast on these elusive saturn features.You can look for a rift in the seb a whitish brake in the band sometimes it isn't too hard too see.

#3 JayinUT

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Posted 16 March 2009 - 10:24 PM

Kris,

I felt you did a really delightful job in capturing Saturn. I enjoyed your opening of the rings and the detail you provided.

#4 frank5817

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Posted 16 March 2009 - 11:44 PM

Kris,

Beautiful Saturn with moons sketch. :bow: I also enjoyed reading your observing narrative.:waytogo:

Frank :)

#5 TahaSiddiqui

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Posted 16 March 2009 - 11:48 PM

Great sketch, thats exactly how Saturn looks through my 8" too! The past two days anyway lol :).

#6 CarlosEH

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Posted 17 March 2009 - 01:57 PM

Kris,

An excellent observation and report on Saturn. You have recorded the globe and rings very nicely. Thank you for sharing it with us all.

Carlos

#7 Jeff Young

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Posted 18 March 2009 - 07:45 AM

Kris --

Lovely sketch. You might look for a dual nature to the northern belt next time out -- I see the top and bottom of it as very slightly darker than the center.

I also see some lumpiness in the southern belt, but I'm not sure if that's real or not.

Cheers,
-- Jeff.

#8 Kris.

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Posted 18 March 2009 - 01:08 PM

thanks for the comments everyone!

next time, i'll try to see some structure in the northern belt using a little less power!

#9 Dean Norris

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Posted 18 March 2009 - 01:59 PM

Kris, That is a beautiful sketch. One thing I noticed the other night when sketching the positions of Saturn's moons was this- I left telescope to go inside and get my clip board to sketch with. I turned on the light and decided to sketch some before going back out. When returning to the telescope my eyes were no longer dark adapted and because of this Saturn appeared slightly fainter but with more color and contrast on the globe. The belts that you so carefully have drawn were easier to see. Have you noticed this effect? I have heard others in their posts refer to this and I have seen it too. Thank you for posting. Dean

#10 Kris.

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Posted 18 March 2009 - 03:05 PM

Dean, i guess that's very possible. also after staring a longer time at saturn, which is quite a bright object itself, your eyes can get 'saturated' from the light. kinda like 'blinding' your eyes when observing the moon at low magnification. therefore the dark features stand out more easily at first, and when your eyes gradually become dark adapted again after some time, your eyes may pick up more subtle details, but the major features become seemingly less contrasty?
i don't know this makes sense, but i've noticed the effect too anyway :grin:
a bit like 'resetting' your eyes?






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