Small beginners scope shoot-out 8th of December 2012

Its funny how things sometimes don't turn out the way you want it to. My plan for tonight was to just take it easy and do some nice semi dark sky observing from my usual site at Solstice Canyon in Malibu. I had with me my Celestron NexStar 102GT and my new old stock Orion 76mm 3 SpaceProbe. I had plans to do a small scope shootout between the latter and the Celestron Powerseeker 70mm refractor, seeing how both have very similar apertures. However I deemed tonight to not be that night. Weather reports had the skies down as clear all night. But seeing how the weather has been so iffy the last couple of nights, especially with the marine layer and all, I was not holding out for a long observing session. But I did not intend for it to end the way it did either. I got to my site at about 10pm and hiked into the park, only to find that Terry was not there. No biggie. I will just set up and get some observing done myself. As it turns out I only managed 1 hour before the fog rolled in. The air was very moist and the OTA's were all drenched in dew. Geeze only managed to look at M42 and M31and its companion galaxies. So much for semi dark sky observing. After beating a hasty retreat and getting back on the road, I noticed the fog lifting as I drove away from Malibu. Turns out I should have just stayed at home!

It was 11.30pm by the time I got home. Seeing how the skies were clear, I decided to do what I had planned to do in the first place anyway, have a small scope shootout. I had recently acquired four small scopes (two Orion FunScopes) on my trip to NorCal over Thanksgiving. The two I was going to put head to head was the Orion SpaceProbe 3 and the Celestron Powerseeker 70mm. Its amazing what you can get for so little money these days. I remember back in the day I could not even afford a 60mm alt-az refractor with its pathetic 0.965" accessories. For less that a hundred greenbacks, one can get a fully functional telescope these days. All one has to do is be careful where you buy them from. Most scopes in these price range have fairly decent optics capable of opening up newbies to the wonders of stargazing. The bugbear of these scopes has always been their substandard accessories and totally inadequate mounts. Both these scopes had most things in the right place, decent optics, a okay if not fantastic alt az mount (which is easier to master and makes more sense on small scopes such as these...I do NOT recommend EQ mounts for beginners since it takes a while to get used to its motions) and some serviceable accessories.

The SpaceProbe 3 came with 25mm and 10mm Orion Explorer II 3 element eyepieces which looked to be fully coated and a pathetic 5x24 stoppered down finder (I got this scope on clearance as they were cleaning out their warehouse......for a crazy price so who can refuse?), a collimation cap, a short screwdriver for collimation and the primary mirror was center spotted (nice touch Orion!). The 70mm Powerseeker I purchased brand new. Also a fantastic Black Friday price. Scope came with an alt az mount not unlike the one on the Orion, but I noticed the legs were of a much thinner stamped aluminum. Unlike the Orion, this scope came with the preferred red dot finder (similar to the Orion EzFinder II), a plus point, an erect image diagonal, plastic Ramsden and HM eyepieces (20mm, 10mm and 6mm from memory) and a dinky plastic tubed 3x barlow. Other than the finder, everything else was a setback from the accessories that came with the Orion. Also the optics on these only seemed coated. I guess with a rather long focal length, this scope should perform okay.

As they say, the scope is only as good as the mount that holds it. This rings true, whether it be for advanced scopes costing thousands of dollars, or beginner scopes. The main problem with "departmental store" junk scopes has always decent to great optics mounted on junky tripods that quiver like jello when rapped. Both these scopes had similar looking mounts. But this is where the similarity ends. The Orion SpaceProbe had a really nice alt az mount that was a joy to use. The slow mo knob for altazimuth worked very well and I found myself thinking I was using a dob mount at times. The Sky and Telescope reviews for this scope had the same conclusion. The Powerseeker alt az mount looked similar to the SpaceProbe, on the surface. However the tripod legs and metal tripod head were of a lighter variety and not as stable. Vibrations took a hell longer to dampen down as opposed to the SpaceProbe 3.

With both the scopes setup, I was ready to roll. Its nice how light these scopes are. I managed to carry both of them downstairs easily. They also have adjustable tripods so they should accomodate kids (and kidults ;) of all heights. Plonking them down was easy enough. After getting the Powerseeker's finderscope aligned using Sirius, I set out to compare and contrast the scopes. Getting the right magnification to match both scopes was easy too as both had the same 700mm focal length. It was also fortuitious that the Spaceprobe 3 came with a 25mm Explorer II eyepiece to match my lowest power eyepiece, my Meade 24.5mm SWA. From the get go, I decided to use my Orion Dielectric diagonal on the Powerseeker to allow it to reach its maximum potential. I had four objects in mind for testing, Sirius A for star testing; M45, the Pleiades for star testing and flatness of field and coma, M42, the Orion Nebula to measure light throughput and finally the king of planets Jupiter and its four moons for clarity, sharpness and contrast. Summarised below are my findings:

Sirius A: Nice airy rings from the Spaceprobe 3. Star focused down to a nice point, with difrraction spikes visible. Powerseeker showed astigmatism and pinched optics. Would not focus down to a point. Pattern's on both sides of focus not symmetrical.
M45, the Pleiades: Same case as the above. Powerseeker had a flatter field of view and next to no coma. Field was not as flat in the SpaceProbe 3, but nevertheless views were outstanding. Probably due to its long focal length, coma was almost absent. I though I could detect some blurring towards the edges but that could be just me.
M42, The Orion Nebula: SpaceProbe 3 threw up brighter views, despite having a central obstruction. Contrast was also a tad higher on the Spaceprobe 3. This is funny as I expected the refractor to beat it hands down in this respect. Orion's wings were made even more apparent when I used the NPB filter in both the scopes.
Jupiter: No contest here. SpaceProbe wins hands down. This is surprising too as I expected the refractor to do well in this respect. Must have been the pinched optics or something (see below for details). The planetary disk was super sharp in my 6mm Radian, giving a magnification of 117x. Since Jupiter's opposition was just last weekend, the planet exhibited a huge disc with abundant detail. In addition to the two main equatorial bands, I detected at least two other thinner bands, as well as ruffling in the bands. The views were reminiscent of the 102GT and C6, although with slightly less resolution. I don't remember my firstscope, the navy blue 76mm Explorer alt az giving such good planetary views. Must have been the collimation.

Due to the substandard performance of the Powerseeker, I decided to tinker with it in the daytime to see what could be causing its poor performance. Every refractor I have encountered so far has been good off the bat, with the exception of a crazily stoppered down 60mm Japanese scope (JUNK) and the 90mm ST plastic piece of junk I got from Hong Kong. Looking down the business end of the scope , I could see that there was indeed a plastic retaining ring holding down the air spaced achromatic lens. I loosened this, held the OTA upright and gave it a few raps to make sure the objective sat properly in place. I also checked it collimation and found it a little off. The main problem is the plastic focuser drawtube. There is too much play in it when one racks in and out. This is indeed a problem. I wonder if one could wrap some sort of tape around the drawtube to reduce the "play"(Addentum: There are two small set screws at the top of the focuser that can be used to shim the drawtube to remove the slop. Will give that a go and give you guys an update). That is a real bummer as I was all ready to embrace the 70mm Powerseeker as the new entry level 60mm scopes of the past. Celestron will have to work out the kinks and probably have better QC if this scope is to be a contender. Maybe I am being too harsh, but at that price point, there are better alternatives to this scope.

In conclusion, the Orion SpaceProbe 3 came out tops and I can heartily recommend it as a beginner scope. As it has a long focal length, it will give brilliant sharp views of solar system objects, something that beginners usually gravitate to when starting. The accessories that come with it is sufficient that one does not feel the need to get additional accessories. Also it has a rather sturdy mount and is height adjustable to it can appeal to kids of all ages, putting the eyepiece at just the right height to avoid bending and kneeling. 76mm gathers more light than the defacto beginners scope, the 60mm refractor, so one can start to hunt down some of the brighter DSO. While the FunScope is a great bargain and can be an introduction to the hobby, I personally feel that this scope will be used longer since it provides a good range of magnification. The FunScope is only good for low powered views, and from experience, anything above 50x magnification becomes blurry, no matter how well you collimate the optics. Its just the nature of the beast when you have such a short focal length spherical mirror. It is a good introduction, spur of the moment scope you want to break out when seeing is not optimal. By contrast, the SpaceProbe 3, with its almost diffraction limited optics can be brought out and used as a serious observing scope. I disagree with many that small scopes cannot be used as a serious deep sky scope. With dark enough skies and persistence, I don't think you can exhaust all there is to see with such a scope.