Don't impulse buy these please. Once they come into Singapore the first person get bad experience and pass it onto the next and next.
It sounds good to ZOOM near far to get best of both worlds , in reality it's not so simplified.
I don't own or have any personal hands-on experience with these beginner zoom bino.
This message is based on experience with this hobby and some common sense.
You are welcomed to post your own experience to support the product and prove me wrong.
I advise beginner buyers to stay with fixed magnification binoculars. Don't buy zoom bino.
Visual explanation as below on the differences that is not fully understood by impulse buy.
AFOV
Apparent field of view is the visible circle in binocular eyepiece.
For zooms , the lower magnification is at the narrow end and enlarge when magnification is pushed higher.
For fixed magnification design you can get bigger AFOV for wider view.
At the zoom bino product specification , I quote Angular Field of View: 4.3° @10x / 2.2° @30x
This translates to 43 degree AFOV at 10x and 66 degree AFOV at 30x.
Fixed bino I quote sv206 6.8 degree at 10x = 68 degree AFOV
AFOV at the same magnification
AFOV with zoom bino vs fixed magnification bino
Notice the Left top and Left bottom , how the zoom bino at 10x sacrifice a lot of viewing angle.
Assuming the user just want to zoom 30x maximum and forgo 10x.
In reality the eyepiece , internal prism , front lens , these 3 parts may not be truly aligned or collimated to point at the exact same spot.
Our human brain can adapt to minor horizontal variation but harder for vertical difference.
When magnification tripled , the error is tripled too. Failure to merge the left and right means the non dominant eye isn't being useful.
Bulkyness of double tube but only using single tube.
Beginner level bino is also prone to wriggle and bending at the eyepiece when pushed strongly against the human head. Youtube bino guru test this bending in his reviews.
https://www.youtube.com/@StOKRATzoom/videos
When the same amount of light is magnified across a bigger surface it's intensity drops lower.
The difference in brightness is not noticeable in daytime as 50mm diameter / 30x is 1.6mm exit pupil , roughly the same as our daytime iris size. Color contrast or vibrancy does reduce.
At night when our iris expand to 3mm and more , using a 1.6mm exit pupil would feel dim and encourage the user to reduce the magnification or increase the front lens diameter.
These effects are different from expecting zoom to be smooth and equal like we see on digital camera LCD screen.
