First time and no detail?

[mattprince]

Hi, first clear night since Xmas so took my lad out to try and look at Jupiter. Using a Celestron Powerseeker 60AZ which is a 60mm refractor. It has a 20mm eyepiece and a 4mm eyepiece. Oh and also a 3x extender. Anyway.... Took us ages to get it to show in the viewfinder and it just didn't look detailed at all. Just a blurry white circle. That was using the 20mm only as using any of the others in any combination and I couldn't even find it in the eyepiece. Any ideas/tips?

Thanks

Matt

[atmenterprises]

Did you let your scope cool to ambient temps outside? Did you let your eyes dark adjust? If the scope can be collimated, does it need collimating? Or maybe the seeing was just bad that night. I'd think you could at least make out a couple of bands.

[mattprince]

Hi we were out for a good half hour so should be cooled enough shouldn't it? Eyes adjusted me could see a lot in the sky. Never heard of collimating so will look into that. Found it really hard getting the telescope to line up with the object as its hard when your so low down and trying to line up with something so high up lol

[bingevader]

It sounds like you need to better align the finderscope with the telescope itself, at high magnification it can be tricky and will then still be difficult to keep the image in view as it is constantly moving.

There should be screws on the finderscope to adjust it with respect to the telescope.

If you can find something with the 20mm eyepiece, centre it in the telescope and then adjust the finderscope until the object is as accurately centred as possible.

I know very little about refractors, so I can't comment on the detail you should be able to see.

Cheers

[spaceboy]

I have the Celestron 60SLT which I am assuming is basically the same optics but in a different OTA. I have to say it is my most used scope as it is so small and portable and over time I have learned to see detail using dark adapted eyes and adverted vision. All this said the views are what they are. With an objective of only 60mm and a realistic highest magnification of x90 - x100 your never going to see a great deal of detail on anything other than the moon or (and with a suitable solar filter) the sun. Jupiter I can make out a couple of the belts and see the rings of Saturn, the phases on Venus and just glimpse an ice cap on mars but again there will not be any noticeable detail.

As for you not being able to find anything with the barlow attached that is more likely due to 1) the magnification is way beyond the limits of the scope and 2) with such high magnification your going to have to be perfectly centred on Jupiter before you up the mag as the FOV reduces the higher the magnification.

[Biggazza88]

+1 for the finderscope issue, at least it's a easy fix!!

Good luck!

[spaceboy]

Sorry I forgot to mention I found by far the best magnification / views are with a 17mm EP which is roughly x41. I can use up to 8mm x87.5 on the moon but the views start to become rather dim.

HTH

[mattprince]

Cheers for the replies. I think we will have a few goes of using it in daylight to get used to how it focuses and then have another go on a clear night. The issue may have been that I was doing it on my drive that has street lights in view and perhaps my eyes weren't getting used to the dark enough as the street lights would get in my view when I moved out of the way to let my son look.

[LeeB]

I use a 60mm as a quick grab and go, the comments above are spot on, the only thing I would add is I use orthoscopic eyepieces, and while they are never going to give you big scope views they and other higher quality eyepieces do help, The red spot is just visible (on good nights) but again as noted above its about good seeing and a trained eye. Try to relax and let your eye learn how to see. I know thats not always easy with a lightweight mount but persistance will pay dividends.

I tend to aim for 60-85x with the 60mm and occasionally if seeing is excellent 120x.

Hope that helps.

[glowjet]

Matt, your 60AZ is a basic 60mm refractor, with a focal length of 700mm, allowing for the basic general guide of 50x per inch you will have a top mag of 118x in perfect seeing conditions, but not often obtainable in our climate, which reduces the viable mag down to something in the order of 25x to 30x per inch. So 70x to 80x or thereabouts is the theoretical maximum mag to use with this scope, to enable you to see any reasonable detail and all this in generally good seeing conditions. Your 20mm eye piece will give you 35x and a suitable 10mm ep will extend this to 70x. The 3x Barlow which you have may be usable with the 20mm ep giving 105x on a night of extremely good seeing, but unless the optics on both are of reasonable quality the image may still be degraded. The 4mm eye piece which you possess gives a mag of 175x way beyond the capabilities of your scope. Another point to remember is that as you increase magnification illumination reduces and if you also have no motor drive to your mount, you will be trying to chase your target across the field of view. Although the foregoing may seem a bit long winded it may help you to understand why you have not been able see any objects clearly. Basically you need to set the scope up during the day to ensure that your finder and scope are focused and centred on the same object, the tip of a distant TV aerial is fine, check that your 20mm does not give you a degraded image. when you have finished setting up for a nights use, re-check your finder to ensure this is still correctly aligned. If you want to add a further eye piece to the 20mm I would also support the acquisition a 9mm orthoscopic as these are an excellent choice and will work well in your scope

John.

[mattprince]

Thanks for that. Originally I was thinking of buying the 200p dob. Do you think thy would have been a lot better? Can't see the point in spending lots on a cheaper telescope if its still a budget one. Does the 200p connect to a pc so you can tell it which planet you want to look at and then it will automatically move and track to that?

[glowjet]

If you were thinking of buying the 200p Dob to start with, can you say, other than cost what made you choose the 60mm refractor ?, as there is a mountain of difference between the two scopes, as the light gathering power of the 200p is well in excess of the 60mm refractor. The Dob is a widely used scope among forum members, especially the 200p, the Dob also lends itself to future adaptation onto an equatorial mount and with the addition of a camera, enabling the user to venture into the world of photography. As far as the finding of Astronomical targets and subsequent tracking from a computer, this is outside my area, but as far as I know, and someone is bound to sing out if I am wrong, apart from your scope, you would need a suitable equatorial motor driven mount, with GOTO facilities such as the EQ5-EQ6 series, lap top, probably additional electronic hardware, to make things compatible and sing from the same hymn sheet, sky chart program such as Stellarium and the appropriate software, however, GOTO has its own data base and is capable of finding and tracking many thousands of popular objects without the need of a laptop. Or alternatively you can go the whole hog and go down the video camera route, there are custom cameras that will attach direct to the GOTO scope and relay the object direct onto to a TV screen. this is being done on the forthcoming TV Star Gazers Live commencing next Tuesday. Whatever your alternatives are, to upgrade to what has been mentioned, you are going to need very deep pockets indeed HTH

John.

[cantab]

I have a similar refractor. In a 20mm EP the main cloud belts on Jupiter are visible but not super-obvious, they do get a little washed out by the glare from what is a bright object. Finding the best focus isn't easy either, you need to make small adjustments.

[umadog]

If it was blurry, then you likely weren't in focus. You should be able to see the cloud bands with that scope. You don't need to be dark adapted to see detail on Jupiter. It's bright enough to activate your cones (that's why you see colour on it) so dark adaptation is mostly irrelevant and my even be counter-productive depending on your aperture and magnification.

Inability to see the clouds bands is not because of glare due to the planet being too bright. In absolute terms it's not at all bright. Fine colours become easier to see with larger apertures where the planet is brighter at the same power. If the cloud bands look washed out then that's due to lack of contrast. Contrast is lower in smaller scopes, poor seeing conditions (turbulence), badly aligned optics or simply bad optics (fairly rare these days).

The rule of thumb for 50x per inch is true for good optics, but the atmosphere limits us to about 200x on most nights. This is a hard limit and it doesn't depend much on the aperture. So it's not accurate to say, for instance, 50x per inch on a good night and 30x per inch on a bad night. On a 10" scope, 30x per inch will exceed the seeing limit on most nights. Scopes smaller than about 4" (4*50=200) aren't seeing limited on most nights. In other words, you should be able to should be able to use all 50x per inch on most nights if the optics will handle it. You can stop down a larger scope and see that in action. In fact, the lower resolution of a smaller scope means that it may well churn out nice Airy disks at 50x per inch on a night when a bigger scope shows stars as large fuzzy balls at 15x per inch.

[emadmoussa]

Well, the 60AZ is a basic telescope. I doubt you'll get detailed view of Jupiter regardless the of eyepieces you've got. The practical magnification power of this scope is limited - I would say probably around 100-120x. Any high magnification eyepieces will exceed the actual ability of the telescope and you'll get blurry images.

[bendiddley]

thumbs up on the 200p, that's what i've got and it is amazing! i don't have a goto version just a manual, but i love it that way as i like the reward of findings things myself. if you have any more budget i would get the 200p, maybe sell up the refractor, you won't regret it, just make sure you also get some decent eyepieces, they're just as important as the scope itself! good luck