False specs, it's probably only 7x magnification
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#1 (permalink)      6/5/2022 4:30:54 AM US Central   quote/reply + tips
sheepish
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False specs, it's probably only 7x magnification
An objective lens diameter of 50 mm with an exit pupil diameter of 7.1 mm suggests it's only 7x magnification. This is supported by the angle of view of 7.8 degrees, which fits perfectly with 7x magnification, but is impossible for 20x.

The lower magnification and wider exit pupil would be an advantage for night use.
#2 (permalink)      6/5/2022 9:51:12 PM US Central   quote/reply + tips
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lydia
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sheepish, we have contacted the manufacturer of the SKU 9619134, and the manufacturer told us that the spaces are correct. It is 20X magnification.
#3 (permalink)      6/5/2022 10:30:19 PM US Central   quote/reply + tips
sheepish
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Incorrect specifications is one of the big problems with Chinese manufacturers. Sometimes it might be because they just don't have a clue what the actual specifications are or what genuine specifications should look like, and are ashamed to admit they don't know or made a mistake. However, sometimes it seems that they really don't care and will say anything to make a sale.

The diameter of the objective lens divided by the magnification gives the exit pupil diameter. A 50mm diameter objective lens with a 20x magnification will thus give a 2.5mm exit pupil diameter (and will seem very dim in low light). A 50mm diameter objective lens with a 7x magnification gives the claimed 7.1mm exit pupil diameter (and will seem quite bright in low light).

The claim of 7.8 degrees perspective for 20x magnification is ludicrous. Further, it's contradicted by the claim of 56m at 1000m, which is only 3.2 degrees, which is almost reasonable for 20x.

Several of the specs are CLEARLY incorrect because they contradict each other.