Can someone confirm that I am not crazy? Lux?

[oreo57]

Originally Posted by alton

That chart is too generic. Are you going to tell me all metal halide lamps produce the same amount of PAR per foot candle?

as I said.. Ask apogee, they are the meter people..

it was a generalization to begin with..
The more blue (and more red for that matter) the less accurate the PAR meter and probably FC/LUX ect meter.

TO BACKTRACK on a few of my earlier statements:
1)I certainly shouldn't (or more correctly didn't plan on) suggesting using a LUX meter in place of any PAR meter due to the lack of response in this blue centric world..
though this is what I kind of did.. Blame it on lack of coffee..

2)The point was that initially to "estimate" PAR vs LUX to show that the o/p's lux measurements was NOT showing a HUGELY bright light in comparison to PAR ect..

3) A TRUE Lux meter (which you can check by putting one under an actinic LED array (blue only) will have very poor response and of course PAR cannot be estimated.
Using an apogee you would have an error as well.. how huge depends on wavelength

[lookout888]

Originally Posted by slief

I am not really sure. I am no expert when it comes to DIY LED fixtures. If it's an easy swap, it would certainly be worth trying I guess but I would defer to those who have more experience than I do. I recall there being a lengthy DIY LED Fixture Q&A thread here. Maybe you should post in that thread. You LED's appear to be multichip ones. You might want to post in this thread and ask the question there. I would suggest including all the info about your LED spectrum mix and some background on your issue. You may also want to refer back to your thread here and the fact that some of us are concerned that you need more blue in your spectrum.
http://www.reefcentral.com/forums/sh....php?t=2128756

I will spend some time reading all that and posting there if needed(Just looked over that link and i have actuly been subscribed to it since it started i was big into reading it but it has been a long time and MANY pages have been added). Again thank you for your time.

I am not sure if all this other stuff is helping me solve my problem but it is interesting Thank you all for the info!.

[alton]

One thing I learned with a foot candle meter is your eyes cannot tell drastic changes. I have noticed when you get over 1,000 foot candles, my eyes cannot tell the difference between two lamps side by side even if there is a +25% difference. I learned this the hard way when I first got into Metal Halides and my DE lamps dropped 50% in 8 months and I lost half of my SPS. One comparison that I have noticed is that if PAR drops off 10%, so will the foot candles. A foot candle or Lux meter is needed to tell us when our lamps/leds drop so we can either replace or turn up.