On my Oneplus 6 I noticed neither OpenCamera nor the OS's camera store the zoom level (or any indication of it that I can see).
The Exif tags for this, I believe, would be related to either digital or optical zoom, and possibly crop factor.
So far I've found some potential candidates (but I don't know how any of this works):
0xc61e DefaultScale rational64u[2]! SubIFD
0xa404 DigitalZoomRatio rational64u ExifIFD
0xc61f DefaultCropOrigin int32u[2]! SubIFD
0xc620 DefaultCropSize int32u[2]! SubIFD
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Anonymous
Anonymous
-
2022-05-11
Cameras with zoom objective (real optical zoom) do store the real/actual focal length information in the exif data. The focal length of the objective is what matter. Real cameras also save all other data of the objective, including the range of focal length of zoom objectives. (Objective is a tube like structure that contains many lenses).
The "digital zoom" is a blatant misnormer, for marketing purposes, it is simply a cropping function followed by pixel multiplication in order to arrive back to the advertised pixel size.
The focal length of the objective does not change when using digital boating. So the 3D scene turns to 2D digital image always the same way no matter how much digital bloating is applied. When the actual focal length of the objective is changed (by optical zooming or by changing to another objective that has different focal length) the 3D scene turns to 2D representation in different way. For example we get the long nose or long legs impressions by shooting at close proximity, from an angle, using a very short focal length objective, and we get the far is near impression using a telephoto objective.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
On my Oneplus 6 I noticed neither OpenCamera nor the OS's camera store the zoom level (or any indication of it that I can see).
The Exif tags for this, I believe, would be related to either digital or optical zoom, and possibly crop factor.
So far I've found some potential candidates (but I don't know how any of this works):
0xc61e DefaultScale rational64u[2]! SubIFD
0xa404 DigitalZoomRatio rational64u ExifIFD
0xc61f DefaultCropOrigin int32u[2]! SubIFD
0xc620 DefaultCropSize int32u[2]! SubIFD
Other candidates?
0xc7b5 DefaultUserCrop rational64u[4]! SubIFD <-- ?
0xc65c BestQualityScale rational64u! SubIFD
Cameras with zoom objective (real optical zoom) do store the real/actual focal length information in the exif data. The focal length of the objective is what matter. Real cameras also save all other data of the objective, including the range of focal length of zoom objectives. (Objective is a tube like structure that contains many lenses).
The "digital zoom" is a blatant misnormer, for marketing purposes, it is simply a cropping function followed by pixel multiplication in order to arrive back to the advertised pixel size.
The focal length of the objective does not change when using digital boating. So the 3D scene turns to 2D digital image always the same way no matter how much digital bloating is applied. When the actual focal length of the objective is changed (by optical zooming or by changing to another objective that has different focal length) the 3D scene turns to 2D representation in different way. For example we get the long nose or long legs impressions by shooting at close proximity, from an angle, using a very short focal length objective, and we get the far is near impression using a telephoto objective.