iPhone Camera darkens/brightens

[manic2511]

Has anyone else noticed that the iPhone camera darkens and brightens, even if you leave it alone for a few seconds?

I put my iPhone on the dock, and left it in 'camera' mode, and just watched the display. After 10 seconds or so, the display went dark, and then went bright again... This continues for as long as you care to watch.

Does anyone know why this happens? Could it be something to do with the CMOS sensor? I have run the test under fluorescent lighting, and also more "controlled" lighting. Whilst the iPhone is better under the controlled lighting, the problem does not completely go away, it's just far less frequent...

 

[wgr73]

Its the auto focus. Its constantly changing the aperture. Tap to focus then take a picture. This is normal

 

[PhightinPhils26]

Has anyone else noticed that the iPhone camera darkens and brightens, even if you leave it alone for a few seconds?

I put my iPhone on the dock, and left it in 'camera' mode, and just watched the display. After 10 seconds or so, the display went dark, and then went bright again... This continues for as long as you care to watch.

Does anyone know why this happens? Could it be something to do with the CMOS sensor? I have run the test under fluorescent lighting, and also more "controlled" lighting. Whilst the iPhone is better under the controlled lighting, the problem does not completely go away, it's just far less frequent...

I am pretty sure this has to do with the auto focus as it tries to focus on different objects it shifts the lighting.

 

[Unspoken Demise]

It is normal. I have noticed it too. You are not crazy.
Welcome to MR.
May I take your coat?

 

[-aggie-]

It is normal. I have noticed it too. You are not crazy.
Welcome to MR.
May I take your coat?

Yeah, it's normal. If you want to waste the battery leave it like that.

Is this the new and improved polite Unspoken Demise?

 

[manic2511]

Its the auto focus. Its constantly changing the aperture. Tap to focus then take a picture. This is normal

I should have mentioned I just have the iPhone 3G, not the 3GS so I can't test out the tap to focus theory to see if it still happens... But it's a good shout!

Can anyone with a 3GS try this? I'm really intrigued to know what's happening...

 

[Unspoken Demise]

Yeah, it's normal. If you want to waste the battery leave it like that.

Is this the new and improved polite Unspoken Demise?

I never said he was getting the coat back.

 

[manic2511]

I've now tried this on 3 iPhone 3G models... The same is happening on all of them.

Has anyone managed to test a 3GS before and after 'touch to focus'?

 

[manic2511]

Just a quick update...

It would seem that the 'tap to focus' feature on the iPhone 3GS also adjusts exposure, color, and contrast. This means that the problem may well not exist in iPhone 3GS models. Can anyone test to clarify? I'd really appreciate it.

Thanks.

 

[RiceRacerDX]

This is indeed normal.

On the 3GS, the camera adjust the settings to the point in which you want to focus. If you focus on an area that is dark, it will brighten the entire picture until your focal point is normal despite what the rest of the non-focal areas look like. If you focus on an area that is bright, it will darken the rest of the picture as well. The same principle applies to the 3G. This is not only an iPhone camera thing either. You can use any normal camera, set it to normal and reproduce the same results....actually, if you use a normal point-and-shoot camera the right way (that is, depress the shutter button half-way to meter first BEFORE you depress the button all the way), it is similar to the touch-to-focus feature of the iPhone in that it will assure that pictures adjust accordingly.