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Summer Jupiter

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foster12

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Reply 4 by micamahler

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Val Maira

Beautiful photo, it must be truly exciting to sit there gazing at the sky... Just a curiosity, roughly how much did your telescope cost? And - if you are an expert - how much does one need to spend to have a telescope that allows you to see "objects" without them being just point-like?

Thank you!

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Reply 6 by foster12

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Milano
zadra wrote:

Beautiful photo, compliments. With my telescope at maximum, one can see Mars

In what sense? Mars is more difficult to observe during this period compared to Jupiter.

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Reply 7 by foster12

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Giove wrote:

... beautiful Foster, I like that there are forum members passionate about astronomy

Thank you! Yes, I am also a long-time user of the Coelestis forum. I also participate in the ALPO Japan international planetary monitoring program, and in the Astrofili.org forum.

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Reply 8 by foster12

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Milano
micamahler wrote:

A curiosity, roughly how much did your telescope cost? And - if you are an expert - how much do you need to spend to have a telescope that allows you to see "objects" without them being just point-like?

Thanks!

Hi! Yes, sometimes it is breathtaking.

Look, I paid about 2500 for mine and I am really satisfied with it. Unfortunately, the evenings in which I can use it to its best are few, due to atmospheric turbulence. The best ones are in summer, with dead calm.

A good telescope that allows you to see the moon and planets very well costs about 250/300 euros complete with motors. I never tire of recommending the 9 cm Maksutovs. They are inexpensive, absolutely portable, and easily allow for magnifications of around 200x. Imagine, it is as large as a half-liter beer bottle, yet it can easily show you Cassini's division on Saturn. If you want, I can suggest something more specific.

P.S. Point-like appearance depends on the resolving power of the telescope. The larger the DIAMETER (and not the focal length), the more you can distinguish fine details and tell a small disk apart from a dot. Any star will always appear point-like. They are too distant to be resolved.

You can resolve planets well even with a 6 cm diameter.

With my telescope of 23.5 cm in diameter, I can distinguish (on the best evenings with little wind and high-altitude turbulence) details of less than 400 meters on the moon.

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Reply 9 by Micheluzzi

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Sorry Foster, but how do you take the photos? Is it a native function of these telescopes?

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Reply 10 by foster12

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Milano
Micheluzzi wrote:

A question perhaps useless, why "summer"?

Because it was re-imaged in the opposition of summer 2011 from Milan, on the top floor of my apartment building at about 5:00 in the morning.

This year, however, the opposition was a few months ago. This is not good because during winter periods, continuous thermal fluctuations lead to very strong turbulence that is highly detrimental to image quality.

Look for example at a star; from being point-like, it transforms into a boiling mass if there is atmospheric turbulence http://www.damianpeach.com/pickering.htm

http://www.damianpeach.com/pickering.htm

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Reply 12 by foster12

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Micheluzzi wrote:

Sorry Foster, but how do you take the photos? Is it a native function of these telescopes?

Absolutely not. I continue to prefer visual observation. Seeing with one's own eyes lights coming from distances that we humans could never reach, and seeing things that only a few men in the world see with their own eyes, fills me with satisfaction.

I use a black and white camera to connect to a PC.

I make a video, choose the sharpest frames and average them, in order to eliminate electronic noise. In this way, one obtains images that were truly unthinkable for the amateur until about ten years ago.

I shoot in black and white so that I can choose which light band to observe. To obtain color images, I do a simple trichromy. RGB.

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Reply 13 by foster12

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Micheluzzi wrote:

Perhaps I am missing the concept of opposition

It is the point of maximum proximity to the earth

Pardon my superficiality.

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Reply 14 by Micheluzzi

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foster12 wrote:

Pardon for my superficiality.

...but don't worry about it, I'm the one who is curious without having any means

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Reply 15 by foster12

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From our side as astrophysicists, we only have theories, big words, and a great desire to understand something.... :D

As for the means, let's not even talk about it.

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Reply 16 by zadra

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Torino
foster12 wrote:

In what sense? Mars is harder to observe during this period compared to Jupiter.

I mean when Mars is in opposition, obviously. And it's a much more modest telescope than yours, that's all. ; At most, I see Jupiter as a pale disk with the four bright points of the Galilean satellites.

The method you use to obtain the photos is interesting; I didn't think videos could be processed in that way.

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Reply 17 by foster12

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Milano

Hi Zadra! What telescope do you have? Diameter? focal length?

The problem with Jupiter is that it has very low-contrast details. Mars, on the other hand, has well-contrasted ones.

The problem with Mars is that (except during perihelic oppositions) it shows up with modest diameters compared to Jupiter.

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Reply 18 by zadra

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Torino

It's a very old reflector, 114 mm diameter and 1 meter focal length. Not that I often have the occasion to use it; between work and other various interests, it has been gathering dust for years.

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Reply 20 by zadra

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84
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Torino

Ah, wow! O_O

I see, it's just that I don't know how to use it (it's a Konica that was given to me when I was a kid).

foster12 wrote:

I shoot in black and white so that I can choose which light band to observe. To obtain color images, I perform a simple trichromy. RGB.

Can you explain the procedure better?

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