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View Full Version here: : Celestron's "Firstscope" - First view


Gargoyle_Steve
03-08-2009, 10:01 PM
Celestron Firstscope - an Official IYA 2009 Product!

(see the attached image, which is Copyright Celestron and borrowed from their website)

It's a 76mm reflector on the smallest and cutest dob mount you've ever seen! The Firstscope has a focal length of 300mm, and comes with 4 mm and 20 mm eyepieces that give you 75 x and 15x respectively. It has a brilliant little sturdy mount, and it just looks amazing!

I saw the add for this tiny dob in the latest mags, and immediately thought how cool it would be for my 10 year old son. I picked one of these scopes up today, and have had it out tonight for a quick test out before giving it to my son (probably) this weekend.

Here's the link to Celestron's site in case you haven't seen these advertised yet:

http://www.celestron.com/c3/product.php?CatID=78&ProdID=568

So - having spent 30 minutes outside with it tonight, what's my initial opinion? I loved the concept of this scope - and I'm really disapointed to have to say that at this stage, if I can't improve it's performance I will be taking it back to return it.

This scope, at least the individual one that I've bought, has issues - serious issues - that may not be able to be resolved by tightening and or collimating things that need tightening or collimating. In fact so far it seems to NOT be user collimatable, not a good thing for a reflector. The back end of the scope shows no collimation screws, and it appears the only screws (on the sides of the OTA tube) would entirely remove the mirror cell. I have also already tightened a couple of things, like one of the screws that hold the bracket for the secondary mirror (a single arm bracket, not a spider).

It also appears to suffer chromatic aberation, ie it has purple fringing on bright objects. Unless this effect is being introduced by the ep's themselves (in which case they must both do it) then this scope must apparently have an inbuilt magnifying lens as per "department store" scopes and other "short tube" reflectors.

Even worse than the purple-tailed flaring comets that any stars become when viewed through this scope, is the fact that you can't even seem to achieve an accurate focus. And I don't mean a crisp solid focus on a star, I mean I couldn't seem to get a clear focus on Jupiter even at 15x! The effect was similar to looking through a pair of binoculars when one side is out of focus with the other - except of course this was happening through a single eye. I've not seen this effect before and can't explain it other than to say that jupiter, or even the region along the terminator on the moon, appeared to be both in focus, and out of focus, at the same time.

For now I can only say hold onto your $149 (which at that price does not include any kind of finder or aiming device, not even a red dot finder - you need the additional "accessory pack" to get a finder) until I can look at this scope more closely in the light of day to see what, if anything, can be done. Stay tuned.

stephenb
03-08-2009, 10:17 PM
That's real disappointing. I would have hope that in such an important year in amateur astronomy, that the people of Celestron would have put more effort into a small scope which many newcomers would have been attracted to as an introductory telescope.
Surely it cannot be that hard to make a inexpensive scope for a beginner that actually works? Even if it is a cardboard tube! With the high quality products coming out of China today, it would be achievable. It looks like it was designed and marketed by a committee with no thought gone into it. I suspect not one single amateur astronomer had any input into this instrument.

Thanks for your review, Steve.

Gargoyle_Steve
03-08-2009, 10:21 PM
It has occurred to me that given that this item IS promoted as a FIRST SCOPE that perhaps this thread may serve better in the "Beginners Start Here" section - moderators please feel free to relocate it if you tend to agree.

JethroB76
03-08-2009, 10:28 PM
This is not the first/only bad review of these scopes

renormalised
03-08-2009, 10:40 PM
Skywatcher are selling a very similar scope to this one in the camera stores. About the same price too, for memory, and given the price, probably very similar in quality.

What are the ep's in the "firstscope"...plossls or "el cheapo" Huygens/Kellners

mental4astro
03-08-2009, 11:01 PM
Hi Steve,

I'm glad I'm not the only one to have had issues with the FirstScope. It is the same scope made by Skywatcher/Synta, but really stripped down, ie-no finder with the FirstScope:

http://synta.en.alibaba.com/product/219935019-200106219/Mini_DOB76.html

First thing I did was ditch the stock EPs & use my own. The stock EPs are poor, & the wrong design for such a fast scope, being Huygenian & Special Ramsden. Even my Kellner EP, from my Celestron C5, really gave beautiful images.

Some degree of collimation can be achieved with the collimation screws of the secondary & using the 'star collimation' technique. A spherical mirror for f/4 does not help.

I've also found that most of my EPs, & the stock EPs, when focused does not draw the focusing tube far out enough to not clear the path of light, causing its shadow to be visible when the stars are out of focus.

York Optical has been good in helping me overcome problems, but it does mean using other EPs.

As it comes out of the box, the FirstScope is dissappointing. It does have technical issues, which the novice using their 'firstscope' will not be aware of, then again , they will neither be aware of the better images this scope can deliver. It will cost money, though. Sort of defeats the purpose of the first scope concept.

Sad, because it is capable of giving nice views.

netwolf
03-08-2009, 11:11 PM
I think i saw one of these at CameraHouse for $99 bucks. It would make nice little begineers scope for kids, if the issues can be resolved.

erick
04-08-2009, 09:49 AM
Buy a Galileoscope, ditch the reflector and put the GS on the cute dob base.

Gargoyle_Steve
04-08-2009, 03:18 PM
Thanks for that link to the Synta version Alexander, yep it's definitely the same scope, except the lack of any finder in the Celestron version and the multiple colour schemes in both base laminate and OTA colour offered by Synta (including the "great names in Astronomy" version, ie white writing on black background, version that Celestron is using).

I did re-read the small English section on the single sheet "Instructions" that came with the scope, and they do mention in quite small print that if you have "problems" refer back to the Celestron website.

That lead me to find that there IS a much larger Instruction Manual available for download from this page:
http://www.celestron.com/c3/product.php?CatID=92&ProdID=568
(click on the "support / files" tab)
The english language section here is 16 pages long - quite a difference to the single sheet blurb included in the box!

Having said that, this really should be included with the scope in the first place! I'm sure there are plenty of potential buyers who would NEVER go searching around a website for an instruction manual that they have no idea even exists.

There IS a section on collimating Newtonian reflectors, however with reference to this scope it only talks about adjustment of the secondary mirror. Being blessed with a laser collimator and an abundance of collimating experience from taming both my 12" GSO dob and my 5" Skywatcher Newt I will have a fiddle with this a bit later this afternoon and see if I can improve things, and as per your helpful suggestions above guys I'll try my "spare" GSO plossls in it instead of the supplied 4mm (Ramsden) and 20mm (Huygens) eyepieces.

I would still like to give this to my son as a surprise / reward for his recent improvements in schoolwork, but only if it's going to provide a positive experience for him, and not turn him away from Astronomy.

As an aside, if you want to see a REALLY good demonstration of Adobe Flash used in a website, then I don't believe I've seen better than the Flash tour for this scope on Celestron's website, use the same link as above and click on the Flash tour tab.

It's ironic - we usually recommend steering away from the wobbletronic grade scopes due to the harm, not good, they will do to a budding astronomers enthusiasm, in this case the mount is brilliantly simple and sturdy, the scope itself is the letdown.

I'll report again after some fiddling with the secondary, and some more testing tonight.

erick
04-08-2009, 03:41 PM
I wasn't being complete flippant (unusual for me!). See this example:-

http://eridanusoptics.com/store/index.php?main_page=product_info&cPath=20_85_124&products_id=641

It's not an actual Galileoscope shown, but the principle would be the same, and probably quite effective.

But I hope you can tweak up the reflector, Steve. :thumbsup:

erick
04-08-2009, 03:50 PM
Yes, pretty fancy flash - but look at the images of Saturn and Jupiter they put into the presentation. That scope will get nowhere near these, of course. I'm much more impressed with the images on the outside of the Galileoscope box - quite realistic of what is seen.

The flash and reported focal length suggest there is no internal barlow lens, Steve. It must have been the eyepieces.

Needs a cheap red dot finder.

mozzie
04-08-2009, 05:42 PM
thanks for the heads up guys i was going to get one for my boys but i think i may hold back for the moment
mozzie

renormalised
04-08-2009, 07:13 PM
Instead of buying something like that, go here B & H (http://www.bhphotovideo.com/c/product/524285-REG/Meade_0805_04_20_ETX_80AT_Astro_3_1 _80mm_Refractor.html). You could pick this scope up and have it sent out here for less than the price of buying it here.

It's a fair bit dearer than the "firstscopes", but you're going to get the kids something that'll last and will perform as expected.

Or goto this page Nexstar 4 and 5 SE (http://www.bhphotovideo.com/c/shop/3392/Telescope_Optical_Tube_Assemblies_C atadioptrics_Cassegrain_.html). Even after paying for freight, these are much cheaper than any place here.

Gargoyle_Steve
05-08-2009, 11:34 AM
Sadly, the final decision is that the FirstScope will be going back for a refund.

I love the idea behind this scope, I think the concept is great and had it worked as intended, or perhaps as expected, it would have been brilliant as a true First Scope either for children, or those who wanted to test the waters of backyard astronomy with absolute minimal outlay. And it really is the cutest scope I have ever seen! I just can't find another word that fits, they are incredibly cute - everyone should at least see one of these live in a store somewhere to understand just how much appeal this scope has.

I REALLY REALLY wanted this scope to work, and have done my best to make it work without resorting to redesigning and rebuilding it.

But it doesn't work ..... not well enough anyway. It's frustrating to see that with some pretty minor design improvements this could easily have lived up to it's expectations, but the manuacturer (as noted previously NOT Celestron but a chinese company) did NOT take those small final steps to create a great little scope. Such a shame.....

So what happened after my best tweaking, in practical viewing terms: well, nothing. I just can't sort out it's weird focus issue, nor the chromatic aberration, nor it's collimation - and therefore it would be just as bad a scope for a beginner as any of the other wobbletronic cheapo types would be.

On a reflector there's 4 different adjustments that must be correct in order to properly achieve collimation:

1: Changing the position of the secondary mirror up and down the OTA lengthwise, so that it is positioned directly underneath the focussor

2: Changing the position of the secondary mirror across the width of the OTA so you can make sure it is centred within the diameter of the OTA.

3: Changing the position / reflecting angle of the secondary to ensure that it is facing properly with respect to both the primary mirror and the focussor.

4: Changing the angle of the primary mirror itself so make sure that it is facing correctly back at the secondary mirror.

The Firstscope scope quite simply is designed in such a way that it cannot be adjusted as per 1 and 4 above - and in the case of my particular unit these 2 non-adjustable factors MAY be supposed to be correct and not need adjusting, but they are both somehow positioned wrong!

Guided by my laser collimator I adjusted this scope as best I could, trying to work around the lack of adjustments, hampered even further by the fact that the secondary mirror wasn't even glued on straight (or level perhaps I should say) to it's holder.

So when it came time to test last night I waited until nearly midnight so that both the Moon and Jupiter would be high and viewable through as little atmosphere as possible, to give the scope it's best chance of performing as well as it could. I tried the 2 supplied eyepieces, and a GSO plossl, and a Meade plossl.

And the view in every case was every bit as bad as the first night!

Jupiter still has strong colour fringing around it, and I can confirm that there definitly is NO internal lens in the focussor at all, as Eric said previously. Combined with the lack of collimation, this gives Jupiter a vivid blusih-purple peacock tail effect when it flares sideways enormously while attempting to achieve focus.

Further to the mystery, the colour fringing was visible through every eyepiece I tried in it and I know for a fact that the GSO and Meade ep's don't cause this effect. Where is it coming from? Stuffed if I know, I suspect off the edge of the secondary mirror somehow.

The laser collimator showed that the secondary mirror is quite simply positioned almost a centimetre too far down the barrel and therefore too far under the focussor, and I'm sure that some of the reflected primary aperture is being lost over the top of the secondary as a result. The laser dot was far from centred on the secondary, it was more like 1/4 of the way down from the "top" of the secondary, and as noted above there is NO adjustment for this type of positioning in this scopes design.

The moon still had that strange "this side is focussed, this side isn't" thing happening that will not go away no matter HOW carefully you adjust it. Poddibly attributable to the secondary position again. Painful, regardless what causes it.

MAYBE the particular scope I have is a "Friday afternoon" unit, maybe some others are better. I don't know, but I wouldn't risk it again unless they let me bring the laser collimator in to test and tweak the scope right there in the store before buying it.

erick
05-08-2009, 12:08 PM
That's sad. Sadder is if this is common and many people are going to think that is as good as it gets.

You want cute? See attached. :)

netwolf
05-08-2009, 11:02 PM
Eric that looks like a newer model of the older Edmund Scientific Red ones.
See review here.
http://www.cloudynights.com/documents/astroscan.pdf
One very interesting things about these is that because of there spherical base, they are actually lend themselves to have a clock drive added. The rotation of the sphere can easily mimick the rotation of the earth. They are not restricted in Alt/Az only due to the sphere base.
This thread has some more interesting facts about larger version by and ATM'er
There was a Astro magizine article and website i cam accross long back on how to make a simple clock drive setup for these. I will try and dig it out.
Edid i found it
http://www.sff.net/people/j.oltion/trackball.htm
check the link there on the mount.
and this alos linked on that site pages scanned from a 93 sky tel mag. http://users.skynet.be/alphonse/skytel.htm

Eric, where did you get the pics from, i would love to get one of those scopes.


Regards
Fahim

mental4astro
05-08-2009, 11:09 PM
The problems of high power viewing could not be overcome, so I exchanged the unit today for another. This new scope was better, but the 'flaring' still exists. It was much better collimated out of the box than the first.

Despite this 'flaring', I'll be keeping this unit. What it offers me at low power outweighs the high power issue. Not something I am to use it for.

Now, to create a finder scope monster. The red dot finder arrived this morning too. I am most impressed at how the spot does not wonder while you do!

[1ponders]
05-08-2009, 11:19 PM
The Portballs are great. Celestron put one out and it wasn't a bad little unit. Unfortunately the downside is that the lens that came with it (15mm) screwed into the eyepiece holder and you couldn't easily use another eyepiece. Also not having a RDF was a bit of a pain as well.

erick
06-08-2009, 12:27 AM
I'm searching but cannot find as yet. I pulled them from somewhere a year or more ago,

But they are around - check on this page:-

http://cosmicdiary.org/100ha/?p=38

Eric

EDIT:- Got it!

http://www.hioptic.com/telescopes/reflector/Dobsonian/penguin_F300x76.htm

netwolf
06-08-2009, 12:41 AM
Thanks eric its only 3" though
But I found it has a bigger brother.
http://www.hioptic.com/telescopes/reflector/Dobsonian/index.htm
I wonder if these come with a optical window (to avoid spider based secondary). Hioptic I think is the same group that people have bough that people have got the 127ED Triplet appos from. I noticed on a recent enquy o Northgroup the reply came back from a hioptic@ address from the same person Gilman.

stephenb
06-08-2009, 05:46 AM
Years ago, I longed for that little Edmund Scientific Red scope. I still remember the S&T ad.

I know Dobs are good no frills beginner telescopes, but the hobby needs a manufacturer, who can make a telescope similar to the Edmund Scientific Red scope or "Portaball" type scope which was well made, optically acceptable, and comes with a simple RDF and 1.25" Crayford focuser.

netwolf
06-08-2009, 08:24 AM
Stephen I agree, the Edmunds scope was a good one. From reviews i have read of new nad used units, they are tough little scopes. The particular review i linked mentions the scope being dropped and still retaiing collimation. I would like to think the hioptic model is the same but i kind of doubt it.

Sorry to the OP, as we have diagressed from the original subject.
I was actually thinking of reccomending the little 99$ scope i saw to a few friends who enquired with me for a childrens scope. But I think i will hold off on that for now. Its a pitty. The Orion Starblast 4.5" is a bigger version i think of the same scope, but has had better reviews.

edit here is one review on the 4.5"
http://www.astromart.com/articles/article.asp?article_id=93

[1ponders]
06-08-2009, 08:31 AM
gaa_ian had one of the red Portaball. It was a great little scope. Don't know if you could swap eyepieces though. Certainly that blue one you posted Eric is the same as the Celestron "Portaball" (cant remember the model 'name') and the eyepiece screws in. To put in other eyepieces you have to unscrew the silver barrel of an eyepiece and then screw it into the scope holder. bit of a pain really. The optics on these weren't too flash either. Ian's Portaball was much better.

netwolf
06-08-2009, 08:34 AM
Paul I think the Edmunds one was 4.5" while the one Eric posted is a 76mm.

[1ponders]
06-08-2009, 08:50 AM
I'm pretty sure the one Ian had was around 75 mm as it was almost identical to the blue one. Not sure what brand it was, hopefully Ian will see this thread and post some info.