I bought the Powerseeker 50AZ, which has D=50mm; F=600mm F/12 which comes with 3 eyepieces: 20mm, 12.5mm and 4mm.

As far as I can tell it's not possible to colimate this telescope. As suggested here this is a very important part to see sharp images.

I have tried to observe jupiter and mars with it and jupiter I could see a dim small blurry image and mars a very tiny dot with absolutely no way of seeing details on any of those in what seemed the best focus I could get from them. The only thing I can see details is the moon really. Also I have observed in what seemed very clear sky conditions.

So my question is: How much can I expect to see from planets with this telescope? With this current setup should I be seeing jupiter and mars in more details?

UPDATE: Equipment link


  • $\begingroup$ What about the sharpness of stars with the 12.5 and 4 mm eyepiece? See my answer regarding atmospheric seeing. $\endgroup$
    – JohnHoltz
    Commented Jan 5, 2018 at 18:04
  • $\begingroup$ Since I'm beggining I'm not sure what to expect from stars with this telescope. I can focus with them with 12.5 and 4mm and they become what seem to be well focused but tiny objects $\endgroup$
    – Diego
    Commented Jan 5, 2018 at 18:20
  • $\begingroup$ Please add a link to the device you bought $\endgroup$
    – user1569
    Commented Jan 5, 2018 at 18:31
  • $\begingroup$ updated the question with the link $\endgroup$
    – Diego
    Commented Jan 5, 2018 at 18:39
  • $\begingroup$ One thing that may be worth noting is the time you go and observe. If you are in the northern hemisphere, they won't be rising till the morning, so unless you are out super early, the skies will be lighter, which affects how well you can see stuff in the sky! $\endgroup$
    – MCG
    Commented Jan 12, 2018 at 12:40

2 Answers 2


Currently, Mars is very far from the Earth, so it appears to be very small. I doubt that any amateur telescope will show any details on Mars in this condition. Perhaps when it comes to opposition and is close to Earth, you might be able to see some faint markings with your scope.

Jupiter should show a sharp disk and nearly pinpoint moons with the 12.5 mm eyepiece (48 power). You should see two prominent bands on Jupiter.

The 4 mm eyepiece is probably poor quality, and since it provides 150 power, is too much power for a 50 mm scope. In ideal conditions, the general rule is 100 power for a 50 mm scope (2 times the scope size in mm). The clarity of the sky is not what makes a sharp image. There is a condition named "seeing" that indicates how sharp the viewing is. On some nights, the seeing is poor, so the images will be soft (not sharp) and perhaps shimmering, as if you are viewing the object through a stream of water. (Essentially, you are, except it is miles or kilometers of air!)

  • $\begingroup$ so if I get this correctly I should see some details wit the 12.5mm eyepice then? Should it be expected to see the red spot if good seeing conditions(and of course if it is turned towards earth when observing?) $\endgroup$
    – Diego
    Commented Jan 5, 2018 at 18:12
  • $\begingroup$ @Diego It's close to the limit, but the Great Red Spot should be just barely visible in 50 mm of aperture. Hopefully the optics are in good shape, and the seeing (atmospheric turbulence) cooperates. The GRS has been shrinking over the last decades, and it has lost some of its saturated color. It's more like the Average Beige Spot these days. If you can't see the equatorial belts, you definitely cannot see the GRS. You may notice the GRS first as a dent in a nearby belt. But look closer, and there it is, the GRS nested in between belts. $\endgroup$ Commented Jan 5, 2018 at 20:27

Also see the answer by @JohnHoltz - as he said, the 4mm ocular is way too much magnification for this scope. Anything below 6mm is probably useless.

Don't worry about collimation. Most refractors, if built properly, don't require maintenance such as collimation. I will edit my answer you've linked above to make that clear.

Mars is only observable for a few weeks around opposition, which occurs every 2 years approximately. The next opposition is later this year (2018) in the summer.


Realistically, even in a perfect instrument you may not see a lot of detail on Mars in 50 mm of aperture. If the optics are shipshape, and seeing (air turbulence) is not too bad, you may just barely see Syrtis Major (when it's facing us) like a dark smudge on the disk. If Hellas Basin is full of frost, you may see it as a bright spot. But that should be it. I have not tried to look at Mars in such a small aperture before, but I'll try it this year.

You should be able to see the equatorial belts on Jupiter. I can see them in my 50 mm finderscopes.

  • $\begingroup$ thanks for the details @Florin. Again using the 12.5mm: The thing that I'm still wondering is what I could see from Jupiter was a very small object on the telescope very dim no belts nothing. The only thing I can think of from it is the air turbulence or something like that. From what you guys are saying I should be able to see it witt this equipment it's just a seeing condition that is not helping. would you agree? $\endgroup$
    – Diego
    Commented Jan 5, 2018 at 20:47
  • $\begingroup$ @Diego Could be seeing but I doubt it. Perhaps the scope is not properly focused; gently adjust the focuser until the image is sharp; maybe use the Moon as a reference image. Or point it at a medium-bright star and adjust until the star is as small as it can be. Perhaps the eyepiece is aberrating too much. Or maybe the primary optics are not where they should be quality-wise. It's a little difficult to give a diagnostic over the Internet. If I used the scope for 5 minutes I could tell you what's going on. $\endgroup$ Commented Jan 5, 2018 at 20:55
  • $\begingroup$ thanks @Florin. I actually use this scope to check the moon and I'm able to get really sharp images out of it. I have gently moved the focus but wouldn't get any good sharp images. not even close. The thing is that this scope doesn't give you much control on adjustments so it either the scope that is bad or anything else. Trying to rule that out to really understand how much to expect with this scope $\endgroup$
    – Diego
    Commented Jan 5, 2018 at 21:08

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