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Seeing Saturn's ring

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發表於 2009-2-15 22:42:16 | 顯示全部樓層 |閱讀模式
What is the min magnification we can roughly see the Saturn's ring with gaps? Thanks!
發表於 2009-2-15 23:48:34 | 顯示全部樓層
if you said, with gap, then it's not much... e.g. around 80-100x...

but if you mean gaps, then...............
 樓主| 發表於 2009-2-16 09:47:31 | 顯示全部樓層
原帖由 oldfield 於 2009-2-15 23:48 發表
if you said, with gap, then it's not much... e.g. around 80-100x...

but if you mean gaps, then...............


Thanks for ur reply! Let me show u more explicit by photos.

Excellent means:


Very good means:
[img]h[/img]

Good means:


OK means:


We can see the gap in these 4 photos, but they are in different qualities. I need to know more and plan my budgeting...
發表於 2009-2-16 11:17:44 | 顯示全部樓層
never compare photographs with your visual perception
發表於 2009-2-16 11:31:21 | 顯示全部樓層
The weather is more important than the magnification or the telescope.  To see planetary details, you need a steady and clear atmosphere which is rare in urban areas.  I have never seen even  the "OK" image through the windows of the apartment that I live in.

The contrast of the photos are much more exaggerated than what you see with your eye and image enhancing techniques can bring out things that are difficult to be seen with the eyes.
發表於 2009-2-16 13:06:48 | 顯示全部樓層
CH's comments are very true. The best way to understand them is to join  a star camp.

While "visual Only" requires a start-off budget on equipment, "Photographic observation"  will demand more on budget, which can be 2 or more times higher than the price of telescope tube itself . They all add to more weight in transportation. These factors must be considered when preparing your budget .
 樓主| 發表於 2009-2-16 14:51:11 | 顯示全部樓層
Thanks guys! This show once again I am green in this area. Yes! I think those photos are enhanced by software. Recently I joined the opening of the International Year of Astronomy on 2/7/2009. I tried some telescopes that night. This was the first time I saw Saturn in my life. The telescope was 5" Catadioptrics and Saturn's image looked very small. However, I can still see it's ring. The image is something like this: (Though it is not a good comparision between photo & visual as mentioned by u guys)


From the visual view, I cannot see the gaps. So I talked to myself, if I want to see the gaps, I need to go beyond 5". (i.e. 6", 8" etc. )
Anyway, I would like to join star-gazing organized by experience people. If u guys go to star-gazing and don't mind a novice like me to join, pls PM me.
發表於 2009-2-16 17:18:02 | 顯示全部樓層
Recently the Saturn look like this(http://forum.hkas.org.hk/viewthr ... &extra=page%3D1). The plantary ring is edge on therefore it is difficult to see the gap (Cassini"s Division) at all.
I saw the Saturn on 9th Feb. Under low magnification, it looks like a fishball with a short bamboo stick. Which is yellow-brown in colour.
It is because the plain of Saturn ring is not parallel to the zodiac all the time. Does anybodies know its period?
發表於 2009-2-16 17:59:52 | 顯示全部樓層
原帖由 willis 於 2009-2-16 14:51 發表
Thanks guys! This show once again I am green in this area. Yes! I think those photos are enhanced by software. Recently I joined the opening of the International Year of Astronomy on 2/7/2009. I tried ...


the gap you mean should be cassini division which can be seen even with a good 70mm refractor, of course, when the ring is edge on, no one could see it.
 樓主| 發表於 2009-2-16 18:45:35 | 顯示全部樓層
原帖由 oldfield 於 2009-2-16 17:59 發表


the gap you mean should be cassini division which can be seen even with a good 70mm refractor, of course, when the ring is edge on, no one could see it.


Of course, no one can see it as it is edge on. But what I meant is that even the details on the planet itself is blurred, just like the last photo I posted. BTW, do u offen go remote area, say Shui Hau, to do star-gazing? Or just do star-gazing at the window or the roof?
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