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Beginner needs help with focus


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If you are out of focus then stars and planets will appear as distinct discs, rather than points. Looking at the moon and getting focussed on that first might be worth a try, and will give you confidence you’re focussed
 

However, as you say you’re seeing “points” I think you probably are in focus, and it might be worth checking a couple of things.

First thought is you might not be using enough magnification (ie not zoomed in enough). What eyepiece have you been using and what planets have you been looking at? Uranus isn’t really going to appear as a disc (it’s just too distant without a lot of effort), but Venus, Jupiter, Mars (and Saturn when it’s around) should readily appear as discs (even through binoculars tbh). If you’ve been using a 25mm eyepiece I think you would have seen discs at least but perhaps not much more detail, however, perhaps try an eyepiece of 12mm (which will double your zoom) and see if that helps. 
 

My other thought is whether your tracking is inaccurate, and you’re not seeing the planet you think you are at all, but actually stars! Mars for example appears distinctly reddish-orange with the naked eye so through the scope you should definitely be seeing colour whatever eyepiece you use, and probably even if you’re out of focus. This may sound like a crazy suggestion but mounts are not perfect. My own experience with a 4SE is that it will be more accurate in some parts of the sky than others. When you’re looking at any of the bright planets, say Mars, you should see it dead centre of the red dot sight- if it’s off through that then you’re not seeing it through the telescope. Again, checking with the moon (when it’s around) might be worth a go too, as it’ll be obvious whether the mount has taken you to the right position or not. 

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You are probably expecting too much. I looked at several planets a couple of nights ago with a C8 SE with the following results, using mostly a 25mm eyepiece.

Venus: small dazzling disk, no detail. Could just make out the phase.

Mars: bright orange dot, no detail, could just make out some phase. 

Uranus: faint dot, just distinguishable from a star (no diffraction rings).

Moon: nice detail, lots of large and small craters visible.

I started doing planetary imaging (which you can do with a C8 SE) some years ago, as it was the only way I could see significant detail on the planets.   To see any detail visually, you need the right high-power eyepieces and some observing experience.

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This is all super helpful. I have had success with the moon in great detail. I bought the eye piece kit with a few options down to 6mm. I think there is a 17/13/8/24 and a doubler.  I will try to make sure I am on the right thing and not just a star but I think I am. I was looking at Jupiter Mars and Venus. Again not much to see and thought I would see more. Is it possible to see Saturns ring with this telescope. 

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I suspect you're not on target. Jupiter is a good one to start on because if it's in focus, you'll see the banding on the planet and the moons will be dots if they're not in front or behind the planet. It'll be distinct and will not be mistaken for stars. Your scope has a long focal length, so initial star alignment is critical otherwise any gotos will be off and a lot of the time you'll just see the blackness of space.

Out of focus stars will look like rings/doughnuts all across the field of view, once you see these it doesn't take much focus turning on a sct focuser to go from one side of out of focus to the other. Anything beyond these two points you won't see anything at all, which is why the suggestion of the moon for focusing is wise.

You'll certainly see Saturn's rings, I've seen them in my 360mm focal length refractor.

Edited by Elp
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1 hour ago, Matt999 said:

This is all super helpful. I have had success with the moon in great detail. I bought the eye piece kit with a few options down to 6mm. I think there is a 17/13/8/24 and a doubler.  I will try to make sure I am on the right thing and not just a star but I think I am. I was looking at Jupiter Mars and Venus. Again not much to see and thought I would see more. Is it possible to see Saturns ring with this telescope. 

That’s great news, so at least we know focus isn’t the problem 👍🏻 And you’ve got some eyepieces to try out. The smaller the eyepiece focal length, the more magnification you get, so worth doing some experimenting.
 

 mag= telescope focal length / eyepiece focal length. Your 8SE is 2032mm, so a 20mm eyepiece gives near enough x100 magnification. A 6mm is around x340. In my back garden I don’t usually go above x150 as I’m in a town and the atmosphere just isn’t stable enough ; see what works for you

Your scope definitely gives you ability to see Jupiter’s detail, after all, Galileo and Cassini were spotting the moons of Jupiter, the gas clouds, red spot etc over 300 years ago with equipment that probably looked more like a Pringle’s tube😅

Jupiter is low in the sky at the moment though, so it’s not ideal conditions - and that could be your problem. Will be higher again come October. Mars is higher at the mo and you should be seeing its noticeable red-orange colour, but detail will be less obvious

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On 29/03/2023 at 16:33, Matt999 said:

This is all super helpful. I have had success with the moon in great detail. I bought the eye piece kit with a few options down to 6mm. I think there is a 17/13/8/24 and a doubler.  I will try to make sure I am on the right thing and not just a star but I think I am. I was looking at Jupiter Mars and Venus. Again not much to see and thought I would see more. Is it possible to see Saturns ring with this telescope. 

Years ago I used a 4.5" Newtonian I forget the eye piece , I was able to see rings of Saturn , Jupiter and the red spot, 4 galilean moons. My Night sky was Black Scale B1 . Both Saturn and Jupiter were small discs, however zero color they were just shades of gray (black and white) If I recall it is not possible to see color with Telescope, at least with small ones. I did write to Mount Palomar to use the  Hale Telescope, they wrote back and said Not available. I did however get to look thru one of the Largest Refractors 20" In Denver CO. very nice Moon was amazing, not recall what else we looked at that night. This during Halley's Comet last visit.

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