[andrewb]

Originally Posted by jambutty

Am I supposed to tremble in my boots because your patience is thinning Cyfr. That’s a bit presumptuous isn’t it?
Why not? In any case who the heck are you to tell me what I can and cannot do? A light meter, as used by photographers to determine the level of light falling on the subject, is nothing more than a solar panel in that the meter uses the light from the subject converted to a tiny electrical current to move a needle across a dial to indicate optimum aperture size and shutter speed settings.

I think it's ever so slightly silly to play the 'Who are you to tell me what to do' card when we're talking about how to conduct fair experiments here not how you should go about your daily life.

I don't have any knowledge of photography admittedly. I don't know how their light meters work but if it's from a solar cell, there are many different types. The one in your calculator is about 10% efficient in terms of how much of the spectrum it can use, where as roof type panels are 40-45% efficient.

Originally Posted by Jambutty

So explain to me why when I spark up my fag lighter and hold the flame close to the solar panel the calculator works? The same goes for a candle flame or a flame from my gas stove.

As previously stated, solar cells work best from red light wavelengths. Flames are incandescent in the same way filament bulbs are which means a lot of the light is from teh red end of the spectrum. Therefore your calculator will work fine from them.

Originally Posted by Jambutty

The glow from my computer monitor or TV screen.

I thought that would be rather obvious to you as you produced the information about RGB earlier in the thread. Red light is present, therefore your calculator works fine.

Originally Posted by Jambutty

Explain to me why my calculator will not work the further away it is from any light source.

The light spreads out as it gets greater distance. In the same way you can spray deodorant and it spreads out.

Originally Posted by Jambutty

Explain to me why my calculator will work with light from a blue bulb, a red one, a yellow one or a green one. I’ll grant you that I have to bring it closer to the source though. No doubt those coloured bulbs will also emit a little of the remaining colours but each bulb’s major emission will be in that colour. I don’t suppose that it would have anything to do with the intensity or brightness of the light would it?

I'll be honest and say I don't know. It should not work in blue light. I'm sure there is physics to explain it, like the efficiency of the filter, perhaps it allows some of the other wavelengths of light through but not many, hence explaining why you have to be close to the source.

Another reason could be any external light thats not coming from the blue light bulb such as light from another room, sunlight from the window, street lamps, anything.

Don't let this put you off the truth though, filters just arnt something I know about in enough detail to explain the anomaly. The rest however does explain that they work best from red light.

Originally Posted by Jambutty

Good! You finally agree with what I have been stating all along. The colour of light does not come into the equation just its brightness or as I prefer to call it the intensity.

I wasn't going to patronize you by making additions to what I was writing, I especially considered the sentence you quoted but assured myself that you would read the rest of my post in regards to the certain frequencies of light that solar cells work off. They work best off the red frequencies.

All your blathering about the light spectrum is just a red herring.

No, they're actually the key to the whole debate. The sooner you accept them the sooner you will realize why your calculator works less well with a low energy light bulb. They mainly emit a different kind of frequency which solar cells can't use.