are there any geniuses here?

ok I know there are some geniuses here but I am specifically wondering if anyone can make iphone apps. There are a lot of light meter for photography apps but I think a very simple light intensity meter would be cool. I know you couldnt make real lux or lumen readings because all the light is not captured, spot vs. throw beams etc. etc. What I am thinking of is just a very simple tool that measures the intensity of the light. You could use this for comparisons like when you change a variable on a torch. Say you swap lenses and want to see if it makes a difference. Shine the light at the phone from a given distance and record the reading. Then try the same light, same distance with the other lens. This would work for batteries, driver, really any variable. My idea would also be to make an app specific unit of measure to avoid any kind of confusion and so nobody would think it is something it is not. I would call this unit a BLF.(with permission of course).

Example I tried my Q5 with a trustfire flame 2400 and got 3709 BLFs, tried an IMR whatever and got whatever BLFs.

Im not sure the iphone, or android phones, have this capability but because all of those lightmeter apps are possible then I think this would also.

I would love to have something like that on my Droid. Probably some complicated reason why it can't be done.


I would think the lightmeter apps just take a snap and then average the pixcels levels to come up with a shade of grey they assign a value to.

I suspect trying it with a flashlight pointed at it would result in everything being maxed out and no real data being possible.

Not that I have a clue how they actually work.

The hardware might not even be able to handle that much light. I don’t know

There's an app in the android market called "light tester" that will display lux. I tried it out a few months ago, but it didn't work for the droid X.

Crudely put, lossy compression integrated into the camera's electronics makes this tricky. Since the whole point of JPEG is to remove "less important" data we need to bypass the image crunching stuff.

If you can pull the raw data off the sensor and play some tricks like the HDR guys do then this ought to be possible. If the camera API allows it. Otherwise hardware hacking will be required.

The firmware available for a lot of Canon compact cameras will let you do these things.

The volume of data means it'd be far easier to move the processing off the device which is heavily constrained in power consumption and CPU power.

If the camera is rigidly mounted then it ought to be possible to "subtract" a control shot, leaving just the beam data.

I have read of image analysis using a digital camera - it was aimed at educational use and has been mentioned here. It would provide a starting point. But I've got to go and iron a shirt for work. I'll try to look up the reference later. From memory it was in a thread about lightboxes from several months back.

I knew we had some sharp guys around here. A BLF app. How awesome would that be. Keep the ideas coming

Be-seen you are on the right track. Simple user interface and aimed at comparisons. I like it

As it couldn't be accurate then you may as well just enter the make and how much it cost and it would give you an answer.

A custom hand crafted light, costing over a $1000? That's over 9000 lumens!

A light from a budget brand, costing less than $100? About 4lumens, not that it will work most of the's probably going to burn your house down.

Hmm...Ahh no I've forgotten where I am, that would be the CPF App :P