Why does the iPhone 4S zoom in when recording video?

Yeah I think that's weird- I'm not sure if it's a bug or a feature...

Has to do with the resolution at which photos and video are recorded.

The camera records still photos at 8 megapixels.

The dimensions of which, are: 3264 x 2448

It records video at 1080p (roughly 2 megapixels).

The dimensions of which, are: 1920 x 1080

It's kinda 'cropping' the image.

It's for a combination of reasons. The sensor has an aspect ratio (width to height) of 4:3. Video is shot at 16:9, so it doesn't use all the height available on the sensor. Also, when shooting video, there is a border of pixels set aside for the electronic image stabilization. The combination of the two results in two different apparent zoom factors comparing stills to video.

OK, how about a related extension to the zoom question. Before using my iPhone 4S for taking video of youth hockey games in various small hockey arenas, I used a fixed focus Contour HD 1080 p camera. Some arenas have a netting between the ice surface and the spectators and the ice surface. Cameras with auto zoom tend to focus on the netting rather than the players on the ice. I noticed a similar near by focus problem when shooting video with my iPhone 4S in that the camera auto zoom focussed in the scratches and smears on the plexiglass ( below the netting) so that the players were blurred. I discovered, belatedly that I could fix the focus by holding my finger down on the view finder till the focus rectangle stopped jumping. Is there a strategy for locking the camera into a fixed focus mode that seems to work out OK for the Contour camera?

You can fix this by buying wide lens f.e.

http://www.amazon.com/Camera-Designed-Apple-iPhone-Angle/dp/B0073C0QSE/ref=pd_si m_cps_6?ie=UTF8&refRID=0Y90YAA22VZF7VM0CKWB

It makes things fit much better in your video frame. And Fisheye lens is pretty neat 🙂

Two years later

4 models after

4 iOS versions later

I have the same problem!!!

unbelievable

Rec video zoom

I have a similar problem with just video itself, when recording it appears zoomed in more than it apparently is and so I frame the shot correctly, but then when you play it back, it is zoomed out further and a bunch of non-sense ends up being included in the shot. PS: I know this question is 5 years old, but the problem still isn't fixed.

It's not an issue, it's the expected behavior. You can use an app such as ProCam (option 4K max) and you will be able to record using all the sensor.