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First light for Jason 313 – and it’s a winner!

In 1977, when this scope was new, I would never have bought it. In fact, I would have turned up my nose at the idea that anything named “Jason” could be any good. It was a classic “department store” scope to me back then. What we serious amateur astronomers warned newcomers to the hobby not to buy. Among other things, it came with dinky .965 eyepieces when any “real” telescope by that time had 1.25 inch eyepieces.

Man, was I wrong.  I just paid $75 for a used Jason 60mm, f/15.2 equatorial refractor Model 313 Discoverer – and after first light this morning I would declare the objective lens  excellent, if not exceptional, and the mechanics are a cut above an awful lot of stuff sold today to beginners – or for that matter, some stuff sold 30-50 years ago as well.  My measuring rod – my touchstone, if you will – is my Unitron 114 refractor. I love it and I feel it performs flawlessly. The optics are excellent and the elegantly solid and simple alt-az mount is as  good as any I’ve ever used. But it wouldn’t surprise me if the Jason objective equaled or exceeded the Unitron. I just haven’t done a side by side comparison on a difficult target or two yet – but I will.

I had just come off a less than positive experience with a Tasco when the Jason arrived. The Tasco – model 12TE had cost me about the same thing. The optics are acceptable – maybe quite good.  But the mechanics of the alt-az, yoke-style mount left a lot to be desired. I won’t go into detail, but what I did was shift the Tasco to a “modern” EQ-1 mount I bought from Orion about 10 years ago. And that mount – not the Tasco optics – became the first indicator of the quality I found in the new/old Jason. That is, I think the EQ-1 is acceptable for small scopes, but it doesn’t measure up to the Jason mount.  Here are the three “classic” scopes and mounts with the Jason in front, then the Tasco on the EQ-1 mount, and then the Unitron.

Click image for larger view.

If you look closely there are a couple of indicators of the Jason build quality over the Orion EQ-1. For example, start with the simple mechanism for setting the latitude. On the Orion you guess. . .

. . .on the Jason, you can be pretty precise.

You get a similar difference when it comes to the setting circles. Now I don’t take the setting circles seriously on either of these scopes. In fact, in those days when setting circles were the last word in locating objects by  the numbers, what was put on most small telescopes were inadequate. But I’m going to give the Jason circles a try. They are certainly bigger than usual and look like they might be helpful.

Here are the Orion circles – notice they are of different sizes – I’ve got the ruler next to the larger one  . . .

. . . and the Jason setting circles. (You can’t see both circles in this image, but they are both the same size.)

Jason even took an innovative approach to providing a 10X finder – they use the objective lens by  way of a flip-down mirror! (Shades of Questar!)

And finally, as with the Unitron, the Jason tube can be quickly removed – or more important for an EQ mount, the tube can be easily rotated so eyepiece and finder are in a comfortable position no matter where the scope is pointed. (That beats the one-position-only  brought about by attaching the Tasco tube to the Orion EQ-1 by a couple of bolts. Yes, I could use rings and a dovetail, but 60mm rings are hard to come by and cost half again as much as the scope!)

Jason’s good – how good I can’t be sure. Just looking at and using it for an hour or so is hardly a sufficient measure. But at this point I’m very pleased. We’ll see how it wears – and if there are serious changes I’ll incorporate them as comments here. So here’s my experience from this morning.

The finder needs to be collimated a bit and I’m not sure how to do that, but there are directions. In theory this should not happen – or so the owner’s manual claims – but the scope traveled from Utah to Massachusetts and while beautifully packed, that’s a lot of jouncing. It took me a while to reacquaint myself with such fundamentals of the EQ mount as you have to lock it real tight if you expect the slow-motion cables to work – and I was already well into twilight when I discovered the advantage of having a rotating tube – boy, it’s been a long time since I seriously used this type of mount 😉

I don’t think an EQ mount will be easy for my star hoppers (students) to find things with – but I’ll see. In any event it might take more getting used to for them than its worth. It will be easy for my seniors (and other visitors to Drfitway Observatory)  to keep things in view, once I’ve found them, however, and that’s good. I plan to use the 60mm scopes for the Moon, Jupiter, Venus, Saturn, bright doubles and a select group of deep sky objects that show particularly well in this size instrument.

That said, in the end I was looking at Jupiter this morning and was very impressed. (Still a single belt shows – although, of course, you see signs of others, but only one large, dark one.)

Uranus threw me. First I mistook a magnitude 10.5  star about 15 minutes above Jupiter for Uranus – but it showed  even less of a disc than Ganymeade! Then I put in a wider field eyepiece and looked around and sure enough, there was  Uranus off to the northwest and looking in this scope a lot like Ganymeade – only bluer.

The main objective may just be excellent – or it may be exceptional – too early to say.  But it did a fine job on Vega – no sign of false color and a perfect, bright dot with concentric rings.  It was also great on Mizar and Albireo, but what scope isn’t? Well – not all give these perfect little bullet holes.

No comparison testing. I did try it on the Unitron alt-az and discovered what I’m sure John already told me – that the Unitron tubes are just a bit  bigger and so you can’t just drop another 60mm in that mount without compensating for this difference..

Stay tuned. I plan to give this scope a lot of opportunities to prove these first impressions wrong.

15 Responses

  1. The Unitron tube used for the 60mm scope is actually about three or four millimeters larger than the tube on most other 60mm scopes, such as Jason or Tasco. One thing you might try is wrapping a wash cloth around the tube and then clamping it into the mount – you really don’t need much material to take up the extra space.

    But use something that catches the eye – a nice black or red one would go well with the white tube!

  2. Update: I got to use the Jason with a student last night and it gave a great account of itself, showing off the 3-day Moon, as well as an out-of-round Venus and that beautiful pair, Algieba. She also had no problem learning to use the slow motion control to track objects.

    Before that, however, I had two experiences with the scope worth noting.

    First, I collimated the finder so it matches up pretty well with what you see in the eyepiece. I used the Moon as a target and the adjustment is very simple, though it did not work nearly as smoothly as the directions imply.

    Essentially there are four screws on the mirror housing easily reached. The one in the center is a lock and the other three adjust the tilt of the mirror. Directions even show which screw to move to compensate in which direction, but this is easier to do in the field just by turning one and seeing what happens.

    The catch is this: Things did not move consistently. I eventually determined that the screws were in too loosely. I tightened each of them to close to their max, then started backing off a little at a time and achieved collimation that way. I do not have absolute confidence in this system, however. I’lll have to see over time if the collimation holds. In theory, it should just about never need adjustment. In any event, collimating it is no more difficult than using the typical finder bracket to collimate a traditional finder. In fact, easier except that you do need a screw driver.

    The second thing is this. The black knob on the latitude adjust is the same as those used to lock the RA and Declination. (This show sin the pictures above.) Last night I reached in the dark for what I thought was the RA lock and instead got the latitude adjust. Loosening it resulted in the scope falling quickly to 0° latitude. Gave it a big jolt and took me a moment to correct. No harm done, but not a good idea.

    The EQ-1 mount has a stop that you adjust when you set the latitude and this prevents this kind of thing from happening, even if you accidentally loosen the latitude adjustment. So score one for the EQ-1. I need to investigate this to see if I can prevent it from happening in the future. Maybe it’s just a matter of really tightening that knob so it’s not easy to undo accidentally by hand? Hmmm… maybe I can remove it entirely,. Have to explore my options there because I could do the same thing again, or a student could.


  3. Second Upodate: Uh oh – more use and I am nolonger sure that reflex finder is the best executed idea – the advantage to it is brightness – you’re drawing from at least a large portion of the 60mm lens. But, the disadvantage is field of view. Using the Moon as a guide I don’t think the fov is much over 2 degrees. That’s about half the size you want for a finder.

  4. Hi John, just read your comments about the Jason 60mm. I Just bought one off CN for 50.00 in near new condition, a great deal! This was the 1st scope I ever owned, received as a xmas gift from my newlywed bride in 1977. I sold it a few years later and always regretted doing so. I kinda feel the way you do about your Unitron lol. After perusing your website I’ve decided I’d like to give double star observing a try. It seems I never used my old Jason 60mm. to its’ full potential. I;m not very good at star hopping though; but I guess your never to old to learn. I haven’t had first light with my “new” Jason yet, but if your interested in the results I’d be more than happy to let you know.
    Stan Anderson

    • Hi Stan,

      Actually Greg is the one who wrote the article on the Jason 60mm and also owned the Unitron. He’s around here somewhere, so he’ll probably respond soon. I’ve got my share of 60mm refractors, but never got around to picking up either one of those models.

      By all means, let us know how you do with the 60mm Jason. There are a lot of double stars within the reach of a 60mm refractor, and many of them are quite stunning. This time of the year I would recommend Albireo, Omicron Cygni and Omega Cygni, Epsilon Lyrae, and Gamma Delphini for starters (and don’t forget to look for Struve 2725 in the same field, which is also mentioned in Greg’s piece at the link).

      If you click on the “Select Category” field near the top left of the screen and scroll down to “60mm double”, you’ll find a total of eighteen posts there that are good candidates for 60mm refractors. If you scroll all the way down to the bottom of the list, you’ll see Greg’s DSC-60 posts, which are also included in the first list of eighteen.

      Best of luck, and most important, Clear Skies!


      • Yep, I’m here – just a bit tardy looking at the email account that receives these comments. The little Jason should do a wonderful job on doubles and you got it for a great price! But I’m also fascinated by the way you got your first one!

        Actually, there a whole “categpry” for observing with 60mm scopes with 18 posts in it – including a nice introduction by John that you can find here: https://bestdoubles.wordpress.com/category/3c-60mm-double/ – or just go to the category drop down menu on the left.

  5. Hi,

    I was restoring a Jason 313 my dad left me and a gust of wind blew it down to the ground! Wish I saw that water jug idea for stability earlier. So now I have a Jason “T” 313 with a cracked lens, I know nothing about being able to repair it or should I trash it. What would you do? I have more sentimental value in repairing it than practical. It cracked the right third so I was still able to look at the moon with the good part.


    Stu in CA

    • Hi Stu,

      Sorry to hear about the cracked lens on the Jason.

      There really isn’t any way to repair a cracked lens, so it will have to be replaced. There were some Carton 900mm lenses available for a time on the CN classifieds, but I believe the person who had those sold all that he had. You could try placing an ad in the CN classifieds or on Astro-mart for a sixty millimeter lens with a 900mm focal length. It shouldn’t cost much — I believe the Carton lenses were selling for about $30 or so.

      Hope that helps,


      • Thanks John for the reply. $30.00 would be fine. I have been checking craigslist and thrift stores. I was hoping to be looking for eyepieces instead but then had the wind blow me in a different direction. Hoping by chance something comes up. In the mean time it still works although a bit double vision on one segment.

        Thanks again,


  6. Hi. Thank you for the GREAT info on the Jason 313 telescope. We just got one from Craigslist (Jason 313 Towa optics, 1977). If anyone out there in cyber-universe knows where to get a cope of the ORIGINAL 313 MANUAL (or a pdf or scan copy), we would greatly appreciate hearing from you.

    • How about putting a Telrad to replace the Jason’s 313 60mm finderscope?

      Peter Ugarte

      • I think a Telrad would tend to overwhelm it, but a smaller, red dot finder would be an improvement in practical terms.

  7. I got the Jason 313 for christmas when I was about 16 years old.
    I had studied so much about astronomy and telescopes, I had the details of the 313 memorized, I knew everyting about it.
    I opened my new scope on xmas morning…
    The box was missing several items: the counterweight rod, one of the included 3 eyepieces, the solar filter and another part, I can’t recall what it was. HUGE letdown!!!
    I return the scope to the local dept. store it came from (I forgot the name of the store. Long gone now…)
    I then proceed to call the dept. store every couple days to ask about the status. They tell me it will take several weeks, at least, to get another one.
    So I resort to calling every monday afternoon.
    The entire store knows me and the details of the scope after a couple weeks.
    FINALLY, I get the next scope.
    It has everything, like new.
    I still have, everything, of that scope. The box, the foam inserts, the literature that came with that model scope.
    Everything, 40 years old and in like new condition.
    I learned more about science, astronomy, photography, math, etc. from that scope than any other item I ever got from a cheap dept. store!!!
    I have it all, still, in mint condition and it is one of my most prized possessions.

  8. Hello, I am new at this, but my very close friend passed away. I knew he had a telescope and I kind of bought it site unseen. When I brought it home I learned it is a Jason Model 313 with tripod stand. Unsure if I got everything that it came with, but I am pleased with what I have.I’m 65 years old , retired and lookin to the stars. Phil in Indiana

  9. The Jason 313 (or Discoverer 454) has been (by far) my favorite “go to” telescope. I have owned three over the years, and all of them are consistently exceptional in terms of image quality. Using the blue fireball adapter, standard eyepieces can be used. It is lightweight, and it just works every time. Currently have two, having sold my workhouse after it got beat-up with use. They blow away the stuff sold today, unless you are willing to pay high dollar for an apochromatic, this telescope is perfect for size, weight, and portability. Planets are razor sharp.

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