Cell/Mobile phones at light meters?

[kipkeston]

Does anyone know if any cell phones work as light meters? Many have cameras, so many must have some form of metering.

 

[anirbax]

It's possible definitely, but only as a software hack. I don't think any mobile phone supports this out of the box.

 

[jslabovitz]

I've thought about doing this (I'm a programmer as well as a photographer). But like anirbax said, there would need to be software written to read the camera's sensor, average the reading of the pixels, and translate this to a calibrated EV value.

Unfortunately most cellphones are not easily programmable, unless you are a business who can pay large fees to the cellphone manufacturers and/or cell network operators for access to their device. Even then, it might not be possible.

The except to this would be the iPhone, since Apple is making it programmable by ordinary programmers. When I get an iPhone (later this year, perhaps), a lightmeter is one of the projects I'd like to play with.

(Some Palm smartphones are also programmable, but I don't know if there is easy access to the built-in cameras on those phones.)

 

[Spyderman]

I wonder what the API would be like...

if it's just phone.getImage() you'll have hardly any control over the gain (sensitivity), but if it's something more sophisticated, I guess it might be possible...

I'd love to have the abilities and the time to get into this deeper, but sadly I don't have either one.

 

[lZr]

Do it simple: phone.getExposure() returning two values - Speed and Apperture. Calc the EV if you must. The function will be available after half pressing the camera shutter button

 

[jslabovitz]

iPhone API

iPhone API

The programming interface for the iPhone is currently really simple: ask for a photo to be taken (at which point the standard preview & "take picture" button appears), and wait for the resulting image. (The image is just data at this point; it doesn't have to be saved to a file first.)

It doesn't appear that any sort of sensitivity, etc., can be controlled by the programmer. I believe the camera controller (as a part of the OS) does automatic gain control and white balance.

However, everything I've seen indicates that the camera quality is quite good, for something its size. Serving as a lightmeter might still work, given sufficient calibration.

If there's anyone reading this thread that has a jailbroken iPhone, send me a PM and let's talk about maybe building a prototype lightmeter application.

 

[doitashimash1te]

If there's anyone reading this thread that has a jailbroken iPhone, send me a PM and let's talk about maybe building a prototype lightmeter application.

Would you really need an iPhone for that? I thought a virtual iPhone was included in the SDK so you could test your applications even without the iPhone.

 

[jslabovitz]

The iPhone simulator in the SDK unfortunately doesn't support the camera, nor the accelerometer.

 

[Larky]

I could write one for an iPhone if anyone is interested, I'm now an official developer (whoo, cheers, go Apple chants, clapping of hands etc).

But, you may have to wait a little while as it would have to be sanctioned and my schedule is busy.

 

[johannielscom]

I could write one for an iPhone if anyone is interested, I'm now an official developer (whoo, cheers, go Apple chants, clapping of hands etc).

But, you may have to wait a little while as it would have to be sanctioned and my schedule is busy.

That would be the best, I carry both my iPhone and the M3 with me all the time!😀