The Gskyer AZ70400 is a popular budget 70 mm refractor sold as a travel telescope for beginners and children. This page combines three earlier posts on this site, all listings for the same model, into one guide. Details come from Gskyer’s own product page. Some claims in the original listings could not be verified and have been left out, as explained below.
What Gskyer confirms
From Gskyer’s product page:
- Telescope: 70 mm aperture, 400 mm focal length refractor (so the focal ratio is f/5.7, from 400 ÷ 70)
- Eyepieces: 25 mm and 10 mm
- A 3x Barlow lens
- An adjustable tripod
- A smartphone adapter with a Bluetooth remote
- A travel bag
Claims we removed
The original listings included several claims we could not verify:
- “German Technology” in the product name. We found no source explaining what this refers to, so we have dropped it.
- A specific resolution and angular field of view. The original quoted these with odd units, and we could not confirm them.
- Shipping-weight and box dimensions, which do not affect how the telescope performs.
Working out the magnification
Magnification equals focal length divided by eyepiece focal length:
- 25 mm eyepiece: 16x. Wide, bright views. Start here every time.
- 10 mm eyepiece: 40x. A closer look at the Moon and planets.
- 25 mm + 3x Barlow: 48x
- 10 mm + 3x Barlow: 120x
The listings advertised 120x as the maximum, which matches the 10 mm eyepiece with the 3x Barlow. For comparison, Orion lists the highest useful magnification of its own 70 mm, 400 mm refractor, the GoScope III, as 140x. Real-world sharpness at the top of the range depends heavily on the air and the quality of the optics, so expect the best views at 16x to 48x.
Short focal length: pros and cons
A 400 mm focal length gives:
- Wide views, making it easy to find objects and fit the whole Moon or large star clusters into the field.
- A compact tube, good for travel.
- Some colour fringing around bright objects, normal for short-focus refractors with simple lenses.
The smartphone adapter and remote
The included adapter clamps your phone to the eyepiece, and the Bluetooth remote fires the shutter without touching the phone, which avoids shake. Tips:
- Use the 25 mm eyepiece for your first photos.
- Turn the phone’s exposure down so the Moon is not a white blob.
- Focus the telescope by eye first, then fine-tune on the phone screen.
What can you see?
- The Moon: craters, mountains and dark seas, the best target by far
- Jupiter: a small disc with up to four moons lined up beside it
- Saturn: the rings at 40x and above on steady nights
- Star clusters: the Pleiades and the Beehive at 16x
- Daytime: birds, wildlife and landscapes
Beginner tips
- Practise in daylight. Set up the tripod, focus on a distant object, and line up the finder with the main telescope.
- Keep the tripod low and its legs fully spread for stability.
- Give the image a second to settle after touching the focus knob.
- Never point the telescope at the Sun without a certified solar filter covering the front lens.
Who is it for?
The AZ70400 suits beginners, families and travellers who want an inexpensive, light telescope for the Moon, bright planets and daytime viewing. Owners who get hooked usually find that more aperture and a steadier mount make the biggest difference to what they can see.
Quick summary
- 70 mm aperture and 400 mm focal length, so f/5.7.
- 25 mm (16x) and 10 mm (40x) eyepieces, plus a 3x Barlow that takes the 10 mm to 120x.
- Kit includes an adjustable tripod, a smartphone adapter with Bluetooth remote, and a travel bag.
- Best views come at low to medium powers, roughly 16x to 48x.
- Claims of “German Technology” and a specific resolution and field of view were removed because we could not verify them.
Jargon buster
- Aperture: the diameter of the main lens. More aperture means more light and more detail.
- Focal length: the distance over which the lens brings light to a focus. Divide it by the eyepiece’s focal length to get magnification.
- Focal ratio: focal length divided by aperture. A low number like f/5.7 means a wide, bright field.
- Barlow lens: an accessory that multiplies the magnification of any eyepiece, here by three.