well i thought this would help alot of ppl out and so i thought i would do a lil research to help further this along and if it can be built cheaper than buying one thats great cause we all know how expensive the world of fish keeping is wether it be freshwater or saltwater
what data does the ardiuno gave you as an output and how do you translate that to PAR reading? I am new to electronics but would like to learn and prehaps provide some input to help out.
All photodiode will output a small voltage when excited by light but the voltage alone is not not good enough in terms of resolution.
So what you do is apply 5Volts through it and gather the output signal from the diode (0V-5V).
Here's a typical setup (photoresistor/photodiode)
HEh, They needed me to fill out a form on the intent of my purchase... I think it's regular policy these days to make a safer world.
For photodiodes??... maybe its more of a marketing strategy to look into new avenues they can market their products.......... just my 2 cents. Anyways, how is the design and calibration coming along? Any new developements?
Hah, I have no idea what kind of weapons you can make but I know photodiodes are used regularly to detect lasers.. I have heard news stories of people buying cheap components from the States and shipping them to NATO embargoed countries which is a big no-no.
In my research, I found out that a green LED, can read PAR visible light pretty darn well. The spectrum matches up but the resolution is so low I'd need an expensive millivolt meter.
Well, the conclusion on this so far is that the current photodiode is not reliable because it reads Infra Red as well. Different bulbs will have different IR output and will skew the readings. Since a photodiode is the key foundation for this, I'll wait for the correct diode to arrive and restart the calibrations.
I can worry about the cosine corrections and such later. I wouldn't even know where to get a cosine correction filter ... But from looking at the charts & graphs, I can leave it out and call it 'goodnuff'.