F30070 Telescope – a review

Discuss your refractor type scopes here.
Post Reply
Barnacle
Earth Ambassador
Articles: 0
Offline
Posts: 23
Joined: Mon Aug 26, 2019 1:53 am
4
Location: Melbourne, Australia
Status:
Offline

F30070 Telescope – a review

#1

Post by Barnacle »


F30070 Telescope – a review
F30070.jpg
F30070 b.jpg
F30070 a.jpg
I picked up this very common no name made in China scope recently second hand as an el cheapo finder scope for my frac.

The tabletop tripod is not my testing subject, only the optics ad the optical tube assembly will I be commenting below.

The specification sticker on the scope’s focuser says the scope is a 70mm focal length 300mm coated lens telescope, so a focal ratio of F4.3! I am keen to test this claim, as it is very fast.

The focuser is a 1.25 inch barrel, but the plastic eyepiece adapter ring is super thick, and stop the opening down to fits its two 0.965 inch Huygenian eyepieces of H20mm and H6mm.
stop down eyepeice adaptor ring 1.jpg
stop down eyepeice adaptor ring 2.jpg
First thing I notice is that the objective lens does not look coated.
Inside the looking glass.jpg
I can see there is a baffle inside the scope tube, not far from the objective lens, and the focuser draw tube reach not far behind the baffle with its own baffle inside and quite far towards the objective end.
Remove the objective look.jpg
focuser baffle.jpg
I did a light test with the stock 0.965 H20mm eyepiece to see if it operates at full aperture out of the box?

The torch light test shows the telescope tube baffle acts as an aperture restrictor, stopping the scope down to 50mm!
50mm stop down!.jpg
I then did a test on the focal length of the objective lens, it is 350mm, not 300mm.
350mm focal length.jpg
Therefore, the manufacturer has the scope operating at 350mm/50mm = F7 straight out of the box. The label should be F35050 telescope instead. :)

After taking the scope apart and darken the doublet objective lens edges with a sharpie, I moved the baffle as far back as possible towards the eyepiece end by flipping it around and changing over to a shorter focuser draw tube and swapping over to a 1.25 eyepiece adaptor ring, the light test shows the scope operating at 60mm, a 10 mm improvement.
Flip the baffle and push it down.jpg
focuser compare.jpg
You can use instead a Stanley knife to slowly scrape off the plastic to ‘open up’ the eyepiece adaptor ring from 0.965 to 1.25 inch if you do not have a 1.25 inch eyepeice adapter to swap with.

The only way to reach full aperture of 70mm for this scope was to remove the telescope baffle altogether and to swap over to a shorter focuser draw tube, as the telescope tube length is just too short. This means I rely on the drawtube baffle but I find it was sufficient for me. If you do not have a shorter focuser draw tube, you can cut the tube shorter but you will need ‘Knead it’ to rebuild the rack and pinion focuser knub.

The doublet achromat optics on this ‘F35070’ scope is fine operating at full 70mm aperture at F5. I saw the Moon after the above DIY, I did not see any blue edge on the lunar horizon. I am yet to check for astigmatism with a bright star.

To focus without a diagonal with the shortened focuser draw tube, I use those made in China 2 or 3x plastic shorty barlow lens to lengthen the barrel to achieve focus.

In summary, after the above modifications, it is a much more capable 70mm scope or finder scope.

PS: My scope comes with a 5x24mm finder scope, but the objective lens on the finder scope is a singlet plastic lens and the finder scope has been stopped down to 12mm with a baffle. I find the plastic singlet lens operates better than the glass singlet lens when operating at full aperture due to its different refractive index. By using a Stanley knife, one can enlarge and scrape off the finder scope baffle insider the finder scope barrel to let the finder scope operates at its full aperture of 24mm, with minor loss of crispness in the focus as a trade-off.
:telescopewink:
User avatar
StarBru United States of America
Orion Spur Ambassador
Articles: 0
Offline
Posts: 662
Joined: Mon May 13, 2019 1:53 am
4
Location: Arizona, USA
Status:
Offline

TSS Awards Badges

Re: F30070 Telescope – a review

#2

Post by StarBru »


Interesting review, Barnacle. You said it was a no-name scope, so do you know who the distributor is? Thanks!
Bruce

Refractors: Meade AR-5 127mm f/9.3, Meade ST-80 f/5 and Meade 60mm f/12, Jason 60mm f/15 #313, Jason 60mm f/12 #306 S7, Bushnell Sky Chief III 60mm f/15.
Reflectors/Catadioptrics: Meade 10" F/4 Schmidt-Newtonian, Galileo 120mm f/8.3 Newtonian, Meade 2045D 4" f/10 SCT, Meade ETX-90EC f/13.8 & Sarblue 60mm f/12.5 Maksutov-Cassegrains.
Mounts: Skywatcher EQ6-R Pro & Meade LXD55 Equatorial mounts, ES Twilight II and Meade 2102 ALT/AZ mounts, a modified 10" SkyQuest Dobsonian mount, various 60mm EQ mounts.
Misc: Celestron 20x80mm binoculars, Revolution II Imager/accessories, & lots of optical accessories/eyepieces.
Projects: 8" f/2.9 and 65mm f/10 reflectors, Dobson-style binocular mirror mount.
Barnacle
Earth Ambassador
Articles: 0
Offline
Posts: 23
Joined: Mon Aug 26, 2019 1:53 am
4
Location: Melbourne, Australia
Status:
Offline

Re: F30070 Telescope – a review

#3

Post by Barnacle »


No idea Bruce. Each country will have their own distributors.

The seller I bought my scope from got this unit from eBay, and I got it second hand off him.

In this case, the distributor likely rest in China, as it was likely shipped out of China.

Thanks.
:telescopewink:
Barnacle
Earth Ambassador
Articles: 0
Offline
Posts: 23
Joined: Mon Aug 26, 2019 1:53 am
4
Location: Melbourne, Australia
Status:
Offline

Re: F30070 Telescope – a review

#4

Post by Barnacle »


Found a weblink with interesting photos of the assembly manufacturing these 70mm short tube fracs!
https://m.made-in-china.com/product/Ref ... 35075.html
:telescopewink:
User avatar
Lady Fraktor Slovakia
Co-Administrator
Co-Administrator
Articles: 0
Offline
Posts: 9743
Joined: Mon Apr 29, 2019 9:14 pm
4
Location: Slovakia
Status:
Offline

Re: F30070 Telescope – a review

#5

Post by Lady Fraktor »


I like the image of the 150mm f/8 on a aluminium tripod and EQ-3.
That would be a very shaky platform.
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
The only culture I have is from yogurt
My day was going well until... people
Image
Barnacle
Earth Ambassador
Articles: 0
Offline
Posts: 23
Joined: Mon Aug 26, 2019 1:53 am
4
Location: Melbourne, Australia
Status:
Offline

Re: F30070 Telescope – a review

#6

Post by Barnacle »


Good pick up!

Yes, looks like they compromise their large cannons by having all of them shaking on stilts at these bargain-basement prices.

https://www.barride-optics.com/product/ ... Telescope/
:telescopewink:
User avatar
Jamison United States of America
Earth Ambassador
Articles: 0
Offline
Posts: 1
Joined: Mon Feb 12, 2024 12:39 am
Location: Spokane, Washington. USA
Status:
Offline

Re: F30070 Telescope – a review

#7

Post by Jamison »


So Barnacle, was that a thumbs up or down on the f30070? Keep in mind I've never even looked through a telescope b4. I have always had a love for astronomy just always thought it would cost to much to get involved in it. Then I saw the F30070 online somewhere so I got it. Can I atleast see something cool or should I just return for refund? If the answer is return it could you recommend a beginner-ish scope that I could actually see, say atleast a few planets? Thanks for your time
User avatar
Lady Fraktor Slovakia
Co-Administrator
Co-Administrator
Articles: 0
Offline
Posts: 9743
Joined: Mon Apr 29, 2019 9:14 pm
4
Location: Slovakia
Status:
Offline

Re: F30070 Telescope – a review

#8

Post by Lady Fraktor »


Hello Jamison, these are very poor and though they do not cost much you would still be out the price of it.
If you managed to get some decent views of the lunar surface I would be a bit surprised.

I would look at the Celestron and Orion telescope sites to see what is available and ask questions so not to spend your money poorly.
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
The only culture I have is from yogurt
My day was going well until... people
Image
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in

Return to “Refractor type Telescopes”