Celestron FirstScope

[Ags]

I bought a Celestron FirstScope from my 8-year old grandson today. First impressions of the mount were favorable - the mount moves smoothly in both axes, and the whole thing feels fairly solid. It is less than 2kgs, so easy for a child to manage. It has a simple clutch on the altitude axis.

There is no finderscope, but with the low-power EP providing a 3 degree field of view that is not too much of a problem. You just sight roughly along the tube, which gets you close enough.

It comes with 2 EPs, one stamped H20 and the other SR4. A quick examination of the EPs left me feeling guilty that I am inflicting these eyepieces on my grandson. He deserves better! In the Huygens 20mm you can clearly see the inside of the eyepiece barrel, imagine the reflections. And the SR4 is simply unuseable, I think it has negative eye relief.

I had the idea that the scope might be an interesting compromise between binoculars and a small telescope. With a 300mm focal length it would give wide views like binoculars, but with 76mm aperture it would gather far more light than any binoculars an 8-year old might be able to handle. And the FirstScope would provide a stabler view than bins.

I tried out the telescope in twilight on the moon. There was thin cloud so viewing conditions were not ideal. (I will update the review on a better night - I particularly want to have a look at the Double Cluster and M45 with this scope).

I started with my old Celestron E-Lux 25mm plossl. I was planning on giving this to my grandson with the scope - but I won't. The secondary shadow is very obtrusive at this low magnification, so the view is spoilt by a persistent black dot in the middle of the field.

The view is only slightly better in the H20. The secondary shadow is still obvious and unpleasant. So this eyepiece is only usable as a finder eyepiece but a higher magnification must be used to get a pleasing view.

I tried my 17mm Hyperion next. The massive eyepiece completely overwhelmed the little scope, it looked quite funny. The secondary shadow was still intruding. I viewed the moon at the edges of the field to see if distortions would creep in. Contrary to my expectations the moon stayed good across the whole field of the Hyperion - a great result for a widefield EP at F4.0! Of course the conditions, twilight and cloudy, were not ideal to assess this. I will try again on another night to see if my Hyperions really do stand up to F4.0.

I then tried my 15mm Omni plossl. I've never liked this plossl but it worked quite well in the FirstScope. The secondary shadow was still there, but more or less tolerable (this is at magnification of x20). I'll give this EP to my grandson.

I tried my 17mm Hyperion with a 14mm fine tuning ring (i.e. as a 13mm EP), but could not reach focus with this configuration. That's a pity because I think this would have provided the widest usable field of view for the scope - about 3 degrees (about the same as for the H20), but with tolerable central shadow.

Finally I resorted to my highest power EP - a 6mm TMB clone. This EP still gives 1.17 degrees field in the FirstScope. This provided an impressive view of the moon, although pointing the telescope at higher magnification is much more difficult.

Overall I am not too impressed. The scope can give nice views at magnifications of over x30, but neither of the supplied EPs will give the young user the experience they deserve - the H20 shows the central obstruction, and the SR4 is a nasty eyepiece. The central shodow is much more intrusive than I had expected it to be. On the other hand, the FirstScope is probably a bit better that the small refractor I had as a kid.

[Ags]

Correction... I bought it for my grandson, not FROM him! Lol

Tapatalk has one major limitation - you can't edit your posts.

[CGolder]

lol very nice review, i had similar problems but as it was my first scope i jusr dealt with it as i knew no better, i picked up some Sw utra wide plossls which worked pretty well, i got a view of Saturn rings in the 6mm.

[Ags]

I had another go at the moon, this time in full darkness. As I thought, the central shadow was less visible under dark conditions. The 15mm plossl gave a nice view of the moon, and has a wide enough field of view to work as a finder (2.5 degrees).

The moon looked at whole lot better in my 9mm and 6mm though. All eyepieces lacked sharpness - a combination I expect of the general quality of the telescope and the extremely fast F ratio.

It was worth looking at the moon through this little scope though, there was some particularly fine terminator detail tonight.

I'm still viewing through thin cloud so no chance of trying out the pleiades or the double cluster yet.

Not sure really, maybe it is enough of a scope to inspire the child, or it will be a turn off? I'll find out next month.

[Ags]

I finally got to try the FirstScope out on some stellar targets: the double cluster and the pleiades.

Firstly, my 25mm plossl was acceptable at night, with only slight shadowing from the central obstruction. It gave an OK widefield view of the pleiades but an underwhelming view of the double cluster. I could not find any of the bright clusters in Auriga. Admittedly there was a full moon and city light pollution, but I have hoped for a bit more. Fortunately my grandson will be using the scope in the country.

The lack of sharpness of the scope was not so obvious with stars - they were not pinpoint but looked OK. This in conparison to the moon where the smudginess was very obvious.

The pleiades looked very good, bright and fairly sharp in my 6mm TMB clone.

So my conclusion is the scope is no good for daytime use, it's OK for the moon, and a bit better on bright star clusters. From a dark site it might give a good view of the Andromeda Galaxy.

[Ags]

A little addendum - I tried the scope on Saturn in good conditions. Using a 6mm EP the rings were visible and Titan could be glimpsed, but the view was awful with smeary glaring all around the planet.