Unique New Ursa Major 80mm and 100mm tabletops from FLO

[Second Time Around]

Browsing the latest new products from First Light Optics I came across new 80mm and 102mm table top Dobsonians with interesting and unique specs.  What's more, like all FLO's Ursa Major range they're excellent value for money.  These are the main features:

Parabolic f/6.3 mirrors.  The longer focal ratios give sharper images than the usual f/4 and f/5 offerings.  They also work well with less expensive eyepieces.

The fully multi-coated 26mm and 10mm eyepieces are 4 element Plossls with 52 degree FOVs compared with the poorer quality 3 element 45 degree FOV Modified Achromats or Kellners usually supplied.

Solid tube so no shroud to buy or make, but non-collapsible.

Rack and pinion focuser, that I prefer to the helical type often suppled with table top reflectors.

Red dot finder, collimation cap and red light keyring torch also included.

Perhaps the only downside is that there's no dovetail, but that may have added too much to the price.  Hopefully, when they're less busy FLO will let us know whether one can be fitted. It would also be useful to know the secondary sizes.

The prices are an exceptionally low £119 for the 80mm, and £139 for the 100mm!

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-80mm-tabletop-dobsonian-telescope.html

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

 

Edited December 14, 2022 by Second Time Around

[Ratlet]

Those both look like interesting wee scopes.

Cracking eyepieces as well.  Love a 32mm plossl.  Might have to order the 25mm.

[Second Time Around]

Yes, I'd prefer 32mm for the maximum FOV and 12mm for greater eye relief and closer to the 2mm exit pupil that's generally considered optimal for DSOs.  However, the 32mm is £7 more expensive than the 26mm supplied and so would put the price up.

Since they're FLO's own Astro Essentials range of Plossls I wonder whether they'd allow us to swap them and pay the difference?

Whatever, the scopes as they are represent exceptional value for money.

Edit note. On reflection, a 32mm eyepiece would give an exit pupil of 5.1mm.  Although giving a wider FOV this might be too large an exit pupil where there's a lot of light pollution. The same applies to those of my age whose pupils no longer open as wide as 5.1mm.

If you do have a 26mm eyepiece then it makes sense to then add a 10mm as a 12mm would be too close to a 26mm plus a 2x Barlow.  Sure, there's less eye relief with a 10mm Plossl, but those wearing glasses to observe still wouldn't be able to see the full FOV at 12mm anyway.

The £7 extra may be too much in this price bracket, at least for the 80mm.  So on balance FLO may have got it right, even though I'd personally prefer 32mm and 12mm.

 

Edited December 19, 2022 by Second Time Around

[NGC 1502]

Thanks for this, indeed great value compared with what was available many years ago. It’s easy to overlook what a small scope can do especially if the user is determined. (Deliberate repeat-  if the user is determined!).

My main scope is a 10” Dob. And yet my 105mm f4.2 Edmund Astroscan is a very useful little scope. With my 22mm Vixen LVW it gives a nice 3 degree view at 20x. Even from my light polluted back yard it’s a delight to scan the skies. Areas of the sky that reveal nothing to the unaided eye come alive with star filled views. Many brighter Messiers can be seen, wide double stars, a few galaxies, one or two planetary nebulae……

And with my 6mm Vixen LV at 74x Jupiter with the main cloud belts and 4 moons, a tiny Saturn, the globe with faint cloud bands, the ring system resolved from the globe and the shadow of the globe on the rings just discernible…and Titan too…

Either of those 2 scopes from FLO could provide years of fun, such great value.

Thanks to Steve for posting 👍

[Alan64]

Alas, I wish the primary mirrors were parabolic...

https://www.telescope.com/Orion/Orion-SkyScanner-BL102mm-TableTop-Reflector-Telescope/rc/2160/p/134763.uts

[Second Time Around]

28 minutes ago, Alan64 said:

Alas, I wish the primary mirrors were parabolic...

https://www.telescope.com/Orion/Orion-SkyScanner-BL102mm-TableTop-Reflector-Telescope/rc/2160/p/134763.uts

FLO says both their Ursa Major ones are parabolic.

[Alan64]

49 minutes ago, Second Time Around said:

FLO says both their Ursa Major ones are parabolic.

Yes, I know.  Still, we have a mystery on our hands.

[Carbon Brush]

I don't think there is a mystery. If FLO says it has a parabolic mirror, it very likely does have one.
FLO are a retailer with a very good reputation, and a good understanding of telescopes.
Besides, in the UK retailers who make obvious false claims generally get caught and punished!

Don't forget the Orion could well have the same tube and fixings, but a different mirror.
In the same way the accessories are different.
It is up to the individual retailer to specify exactly how a scope is built. Even if several retailers use the same factory for manufacture.

As an example. In the UK we have the 'other' Orion. Orion Optics UK build telescopes for retailers and for direct sale.
You can specify mirror tolerance when ordering.

[allworlds]

It's almost certainly from the same factory as the Orion Skyscanner BL102, KSON in mainland China reportedly, but quite possible that FLO specified a parabolised mirror and Orion didn't.

I note that whereas the full size Ursa Major dobs are budget option, these look a little bit premium compared to other mini-dobs, with the nice collimation knobs, longer focal ratios, and better eyepieces.

The two comparisons I'd like to see. UM 80 vs Skywatcher Heritage 100P, same price. I predict the Heritage has the edge on deep sky but will the UM's collimatable primary and more forgiving f/ratio overcome its aperture drawback for lunar and planetary? And the UM 100 vs the Nat Geo 114, similar story. (The Nat Geo comes with rubbish eyepieces but let's say you buy an Astro Essentials Plossl as well and you're just a tenner above the UM.)

[FLO]

1 hour ago, Carbon Brush said:

I don't think there is a mystery. If FLO says it has a parabolic mirror, it very likely does have one.

Oh dear, this is embarrassing ☺️

The mirror spec' on Orion's website is correct. The mirror has a spherical surface. So the spec' on our page is wrong. Sorry.

This sometimes happens when we duplicate and edit another product page from a similar model. 

Spherical mirrors are easier (cheaper) to manufacture with high surface accuracy. We have removed the reference to parabolic. 

We bought these tabletop Dobsonians direct from the factory because we were concerned supply of other similar models would sell out before Christmas. 

Thank you for noticing the eyepieces. They are noticeably better than those supplied with other similar telescopes. 

HTH, 

Steve

[Louis D]

@FLO Is it possible someone has already bought one expecting it to have a parabolic mirror?

[FLO]

19 hours ago, Louis D said:

@FLO Is it possible someone has already bought one expecting it to have a parabolic mirror?

Perhaps, but unlikely. We added them to our website only about one week ago (later than planned). They will most likely be purchased by a Mum & Dad for their son or daughter. The telescopes will perform well, so I doubt it will be an issue. If it is, they are welcome to return it for a refund (it would need to be a refund because we are unaware of a better tabletop Dobsonian available at the same price). 

HTH, 

Steve 

[allworlds]

That's a shame - but a great credit to a retailer who's involved in the community and can quickly respond to such things.

Based on this discussion, https://www.cloudynights.com/topic/42362-parabolic-v-spherical-mirrors/ the 80 should be close to 1/4 wave accuracy anyway, although the 100 is worse affected. But I doubt it will significantly affect enjoyment of the telescope and you can always try an aperture mask.

[Alan64]

I had first seen that one, from Orion of California, some time ago, its debut having been in June of this year.  I was somewhat astounded, a sphere at f/6.3, and intensely curious.  In the end, it's simply a sign of these leaner, meaner times in which we live.  It appears that parabolas are to become ever so precious.  Orion indicates a maximum power of 204x for its 102mm kit, 50x per inch, and I would certainly hold them to it, not only when observing the Moon.

 

Edited December 19, 2022 by Alan64

[cajen2]

The Skywatcher Heritage 100p has a parabolic mirror (though at f/4) and is also £119....

[FLO]

On 19/12/2022 at 14:24, FLO said:

We bought these tabletop Dobsonians direct from the factory because we were concerned supply of other similar models would sell out before Christmas. 

 

15 hours ago, cajen2 said:

The Skywatcher Heritage 100p has a parabolic mirror (though at f/4) and is also £119....

The Sky-Watcher Heritage 100p is a good beginner telescope, but it has already sold out. ETA April 2023! 

We thought this might happen, Sky-Watcher has a lot of retailers in UK, so we sourced these alternative tabletop Dobsonians. 

Ursa Major tabletop Dobsonians

When you compare specifications (f6.3, collimateable mirrors, Plossl eyepieces), you will see they are worthy alternatives. 

Steve

[Carbon Brush]

FLO. Don't worry too much about the cut/paste slip up.
Everyone does it and when you have an eagle eyed customer base, you will get noticed.
It goes to show there is informed interest in the products you sell, which has to be a good thing.

This one is a minor issue compared to many that are out there.
I am reminded of another much bigger slip on astro goods.
Here is an extract from a thread on SGL, some years back where I contributed......

Around 18 months ago one of the suppliers I use at work started offering a Draper newt reflector. Yes Draper the hammer and spanner people.
Draper had provided a description about it being a dobsonian refractor, good for viewing almost everything visible to Hubble, etc, etc!

I emailed the supplier and told them the error of their ways.
This company sell into education and I told them in no uncertain terms they would be the laughing stock of every school / college science teacher.

I also told them that if this was an example of the rubbish they try to sell, how could i trust anything else they tell me.
The scope was removed from their catalogue and web site.

[Mr Spock]

They look like good starter scopes, Better than some of the rubbish you get in high street stores.

I remember being 16 and buying a bog standard 115mm mirror. I stuck it in a home made tube. It was primitive but looking back it was a great starter. Scopes like these UMs just weren't available then.

[Alan64]

The Sky-Watcher 130(not the 130P) has a sphere at f/7, and has been sold for years, if not decades.  If it must come to that, then a 102mm at f/6.3 is acceptable.

[FLO]

1 hour ago, Alan64 said:

The Sky-Watcher 130(not the 130P) has a sphere at f/7, and has been sold for years, if not decades.  If it must come to that, then a 102mm at f/6.3 is acceptable.

Good point, well made.

Earlier today, I spent twenty minutes writing a post explaining spherical vs parabolic, then abandoned it because I thought it was too deep a dive for what are, after all, budget beginner telescopes. 

Your post reminded me I wrote a blog post five years ago comparing the 130 vs 130p. 

The f/4 Heritage 100 needs a parabolic mirror. The f6.3 Ursa Major 102 does not. It has been designed with a longer focal length to enable a spherical mirror. This is good because spherical mirrors are easier (cheaper) to manufacture with high surface accuracy.

And the money saved can be spent on other things, like a collimateable cell and Plossl eyepieces.  

Steve

[Alan64]

In the end, what is needed are purchasers and testers of these latest models.

[Louis D]

15 hours ago, Alan64 said:

In the end, what is needed are purchasers and testers of these latest models.

Don't look at me. 😁  I just picked up a used 6" f/5 GSO Newt this fall and haven't had a lot of quality time with it.  I wanted a decent dual speed 2" focuser for my big glass.  It definitely benefits from a coma corrector with my 70 to 92 degree AFOV eyepieces.  Of course, these Ursa Major scopes target an entirely different clientele.  I doubt they'll be dropping in Nagler or Ethos eyepieces anytime soon after purchase.

[jjohnson3803]

Could the plastic tubes become an issue?  (I know little of reflectors aside from having previously owned a big SCT and a wee Mak.)

Also curious how much they weigh for the grandkids to move around.

[Guest]

On 13/12/2022 at 15:17, Second Time Around said:

Browsing the latest new products from First Light Optics I came across new 80mm and 102mm table top Dobsonians with interesting and unique specs.  What's more, like all FLO's Ursa Major range they're excellent value for money.  These are the main features:

Parabolic f/6.3 mirrors.  The longer focal ratios give sharper images than the usual f/4 and f/5 offerings.  They also work well with less expensive eyepieces.

The fully multi-coated 26mm and 10mm eyepieces are 4 element Plossls with 52 degree FOVs compared with the poorer quality 3 element 45 degree FOV Modified Achromats or Kellners usually supplied.

Solid tube so no shroud to buy or make, but non-collapsible.

Rack and pinion focuser, that I prefer to the helical type often suppled with table top reflectors.

Red dot finder, collimation cap and red light keyring torch also included.

Perhaps the only downside is that there's no dovetail, but that may have added too much to the price.  Hopefully, when they're less busy FLO will let us know whether one can be fitted. It would also be useful to know the secondary sizes.

The prices are an exceptionally low £119 for the 80mm, and £139 for the 100mm!

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-80mm-tabletop-dobsonian-telescope.html

https://www.firstlightoptics.com/beginner-telescopes/ursa-major-102mm-tabletop-dobsonian-telescope.html

 

Just looking at them it looks like the red dot is mounted with nuts and bolts.  Surely at least two of them would line up and if not a drill would fix the problem.