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This is not a picture from KSP...


Technical Ben

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Many probe photos have highly exaggerated colors, or simply false colors. I don't think there's any green and blue on sunlit side of Saturn, but the photos are beautiful nonetheless.

If the colors are exaggerated, it's not by much. I remember one time several years back, right after I got the mirror refigured (meaning, they improved the quality of the mirror) on my old 18" scope, I wanted to see how MUCH they had improved it. Normally, I wouldn't use a telescope in the backyard owing to the light pollution, but Saturn was visible and would serve as a good test of the mirror's (hopefully) improved figure. So, I set my scope up in the backyard, connected a big box fan to blow across the back of it (it helps thermally stabilize the mirror, setting up a smooth boundary layer), and then left it for three hours.

I came back out with Saturn high overhead. Now, the highest power eyepiece I had was a 5mm eyepiece giving myself about 410X. In all my years observing the sky, I had never seen that not be enough magnification- normally, the image would break down well below 410X. But that night... it looked like I was looking out a porthole in a spaceship orbiting Saturn. Even at 410X, the image was razor sharp. I would have even seen the Encke Gap if I had simply had a high enough power eyepiece. Titan was a nice, well defined, orange orb, and the cloud bands and their colors were easy and obvious. Now, I can't say if I remember whether the cloud bands showed any blue, but I can tell you, the above image is at least very close to real color. I've observed Saturn many times before and since that one wonderful night, but I've never seen it anywhere near to that good again. I actually sold that 18" scope (quality telescopes have great resale value) for a bigger scope that was better at observing deep space objects, but the bigger scope has a much more temperamental mirror and support structure that keeps it from performing to its best potential most of the time. Some day, I gotta get it fixed... but I'm not much of a planetary observer anyway, I spend 99% of the time observing galaxies and nebulae.

Anyway, the experience prompted me into buying a relatively cheap ($60), 3.5mm planetary eyepiece that has not been used at all yet. But someday, hopefully, its time will come...

Anyway, NASA seems to have gotten a bit better about not color exaggerating photos- or at least, they are pretty good now about releasing "real color" images that are in fact, very close to real color.

Edited by |Velocity|
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  • 2 weeks later...

Saturn is an awesome moon system with some cool moons. Titan is probably my favorite. My aunt worked on the Cassini project as one of the lead software engineers and so she got us some time to see the ship in the clean room while it was under construction. Man i would love to see it now.

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I took a picture of jupiter once

jupiterimg3mk2_zps42619909.png

Im not very good at taking pictures :(

Thank you for reminding me of my only photo of Jupiter, which I took last December. A lot of things happened shortly after that made me forget about it entirely. For posterity, let me post it here:

zxDcVVH.png

It's stitched from several individual frames, and the levels were adjusted in photoshop. Considering that it's not taken from space, I think it's alright compared to the other photos here. It makes it all the more real when you line the shot up with your own eyeball. Saturn, unfortunately, is just too small in the sky for me to get a decent photo of with my current equipment, though I can see Galileo's "ears".

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I can't wait for the Juno probe to reach Jupiter in 2016 (It just left Earth recently).

Hopefully it will have amazing photos with its modern cameras and such.

Also America gets a new president, and Star Wars Episode VII will come out.

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I can't wait for the Juno probe to reach Jupiter in 2016 (It just left Earth recently).

Hopefully it will have amazing photos with its modern cameras and such.

Also America gets a new president, and Star Wars Episode VII will come out.

And the Dreamchaser and Dragon start carrying Americans back to space. And the earliest possible date for SLS launch.

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To the forumites that took pictures of Jupiter: Might not be that good when compared to NASA images but consider that you're taking pictures of something that takes light anywhere from sixteen to thirtyish HOURS to get here. That is to say you are seeing details on a thing that is hundreds of millions of miles away.

I call that extraordinary.

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I took a picture of jupiter once

Im not very good at taking pictures :(

No, really - that's quite a nice shot! What size scope did you use and what kind of camera?

Also to ZRM: Same comments - Wow! Same questions if you don't mind - very curious. Your shot looks like it had to be from a 10 - 12" scope I'm guessing??

Edited by JebidiahsBigSister
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Also to ZRM: Same comments - Wow! Same questions if you don't mind - very curious. Your shot looks like it had to be from a 10 - 12" scope I'm guessing??

Nope, I wish I could afford a scope like that. Mine is an off-the-shelf 150mm (5.9") Newtonian, with a focal length of 1200mm. My camera is a Canon 600D (aka Rebel T3i). I attached it straight to the scope with a T-adapter. I think an eyepiece projection adapter might allow me to get better shots of Jupiter and especially Saturn.

The reason the image looks so good for such a small and inexpensive telescope is mainly due to the technique used. I recorded 2000 frames of video from the centre of the sensor. Each of these was reasonably blurry, and quite often distorted by air currents. I then fed all of these frames into AviStack, a free image processing program designed with astrophotography in mind, which used statistical techniques to compute the near final result which I then adjusted the levels of in Photoshop.

Depending on his/her setup, vetrox may be able to get similar results using stacking software like AviStack.

Also, I have realised that my picture looks better scaled down:

4tNX8Yv.png

Edited by ZRM
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Also, I have realised that my picture looks better scaled down:

4tNX8Yv.png

That's an amazing technique with frankly an amazing result from such a small scope. I wonder if a 12 inch could possibly even resolve exoplanets (as dots of course) using some variant of that technique with appropriate blocking of the central star.

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That's an amazing technique with frankly an amazing result from such a small scope. I wonder if a 12 inch could possibly even resolve exoplanets (as dots of course) using some variant of that technique with appropriate blocking of the central star.

I'm content to try imaging other planets in our own solar system first. :wink: Unfortunately, since I purchased my telescope I have yet to have the opportunity to view any planets other than Jupiter, Saturn and Venus (and the only one I have photographed is Jupiter). Where I live (in a town) light pollution is quite high, so the further planets are not easily visible, and irritatingly almost all of the other planets were hiding in the glare of the Sun the majority of the first half of this year. I'm currently in university term time, but in theory when I return home to my telescope in December I should be able to employ the same technique on Mars. Next stop would be to find/write a good implementation of motion blur deconvolution so that I can photograph Messier objects cheaply (i.e. without a motorised mount). This does seem to be possible with the right conditions (e.g. most features must have comparable brightness and the motion is simple) according to academic papers.

I'm sceptical that a normal 12-inch would be able to resolve exoplanets with any processing technique - surely there's a reason that only large observatories and space telescopes detect them?

If I get the time I might upload one or two of the raw frames I captured as well as the processed result sans-level-correction so that you can judge exactly how good this technique is. As a general idea, the best of my initial frames were a bit blurrier and noisier than vetrox's photo, though with practically no chromatic aberration due to the lack of lenses involved. The worst were funny shapes due to air currents and exhibiting motion blur due to my less than ideal mount. The great thing about AviStack is that it selectively chooses the best parts of each frame (and may well skip several frames) at the same time as figuring out how the frames relate to each other and finding the offset between them (which was quite large as Jupiter tracked across the sky and I kept having to adjust the view to keep it in the small field of view). The settings did require some tweaking on my part before I got good results.

Edited by ZRM
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No, really - that's quite a nice shot! What size scope did you use and what kind of camera?

Also to ZRM: Same comments - Wow! Same questions if you don't mind - very curious. Your shot looks like it had to be from a 10 - 12" scope I'm guessing??

ZRM has a slightly larger scope but his focal length is what allows him to make out more detail.

Ive got an off the shelf 130mm 600focal length scope with an orion solar system imaging webcam.

The problem I have is bcause of the short focal length jupiter is to small and therfor i have to have the gain set quite high and so alot of the details are blurred out.

My camera cannot even pick up saturn as its to small in my scope :( However i will say my picture (although stretched up in size a little) is a good representaion of what you will see in the eye piece without any filters. As jupiter is back in the night sky now I'm going to try and take some more pics of it. Also on a side note. The moon is a great object to look at with a small telescope, there is so much detail and i still get amazed at the size of some of those craters!

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