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Full Version: Lightmeter change camera
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Hi!

I would like to see an option in the lightmeter, to change the camera

Now the lightmeter always uses the sensor on the front facing camera (cam for selfies).
Sometimes it is useful, to use the back camera.

--> I was trying to do the following experiment
Link https://www.youtube.com/watch?v=9iWu5s4QfKY
(German)

Experiment
In the video Santa Clause is measuring the brightness of juice. First he measures red berry juice, second he measures apple juice (yellowish). 
After a bit of mixing the juices, he is trying to identify, in wich glas the proportion of red berry to apple is higher.
He does all the measering by using the lightmeter.

I had problems using the front camera for this particular experiment.


Do you think there could be an option to switch camera in the future?
Greetings from Germany!
We plan to support the camera eventually, but right now we do not support any camera at all. The light meter actually is a dedicated sensor, which is usually placed next to the camera (sometimes it is hard to see behind some glass that is not transparent in the visible spectrum). Maybe some phones use the selfie-cam as a light meter and just emulate the real sensor, but I would not expect this as it would drain the battery much more than just a cheap light sensor. Even on the iPhone X (and similar) there is a dedicated sensor in the notch space next to the camer (https://www.eetimes.com/document.asp?doc_id=1332274).

So, we will support light metering through both cams at some point, but it is not yet available in phyphox.

BTW: I think that in the video, the main reason to suggest an app that uses the camera instead of the light sensor, is that it is more widely supported. iPhones do also have a dedicated light sensor next to the camera, but there is no interface for apps to use it, so at the moment there is no support for light metering with phyphox on iPhones at all until we implemented the cameras.
Thanks for your reply Sebastian.

You are absolutely right - i mixed up the light sensor and the camera.
(12-13-2018, 01:00 PM)Sebastian Staacks Wrote: [ -> ]Hi Sebastian:

Regarding this ---> iPhones do also have a dedicated light sensor next to the camera, but there is no interface for apps to use it, so at the moment there is no support for light metering with phyphox on iPhones at all until we implemented the cameras.

Is the light reading from some of the other sensor apps like Science Journal coming through the camera on iPhones?  I have someone working on light experiments using the phone sensors but can only use android.
Any app on i(Pad)OS claiming to do some light reading is using the camera, indeed. Science Journal is rather open about that and is also using a correct unit.

See https://phyphox.org/faq/#faqIosLight on details about the differences.