Borrowing the Club's - PAR Meter

Discussion in 'Equipment' started by lattehiatus, Mar 8, 2013.

  1. bondolo

    bondolo Supporting Member

    I'm in Berkeley and would be interested in borrowing it. It's also likely that I will drive to Santa Clara before the 23rd (likely the 21st if not sooner) and could drop it off for Mark. Now would be perfect timing because I am about to change T5 bulbs and a before/after comparison might be interesting. Actually I am not expecting the PAR to change that much as I understand the aging effects have more to do with spectrum shift than PAR.
     
  2. FeliciaLynn

    FeliciaLynn Supporting Member

    Mike, that would be perfect. I'm done with the meter, so I am ready to pass it off whenever you want it. We could just meet up somewhere this week for me to give it to you.
     
  3. rygh

    rygh Supporting Member

    Sounds fine to me also. I am in no hurry at all.
    Mike: I was planning on going to Erin's on the 23'rd. I could stop by on the way.
    Lots of options.
     
  4. bondolo

    bondolo Supporting Member

    OK, I am out of town on Wednesday but will arrange to get it this week. If opportunity arises to get it to Mark sooner than the 23rd I shall otherwise I will transfer it to him on the 23rd.

    Does the meter have a handle yet?
     
  5. FeliciaLynn

    FeliciaLynn Supporting Member

    Denzil used a zip-tie to turn the cord so that that sensor will sit flat when you place it in the tank, but there is no handle. I just ended up holding the cord to keep it where I wanted it while I was measuring.
     
  6. bondolo

    bondolo Supporting Member

    I've already spent some time playing with the PAR meter and was shocked to see how much difference replacing my 11-15 month old T5 tubes made. The color shift was very noticeable even though I was replacing with the same ATI tubes. I have to assume that the color shift also made a big difference in the PAR because the PAR values were much higher with the new tubes. The T5 tubes are: 550mm 24W ATI Blue Plus X2, ATI AquaBlue Special, ATI Coral Plus in an AquaticLife fixture with a quality reflector.

    Before (adjusted)
    Surface ~12cm (highest) : 255
    Sand back ~55cm (lowest) : 66
    Sand front : 81
    SPS left: 170
    SPS right: 178
    LPS area left: 86
    LPS area right: 78
    Far right corner: 74
    Far left corner: 70

    I must also admit that these "Before" values were taken after I cleaned the glass top and splash shield of all salt spray, dust and salt creep. The first values I read before cleaning were even lower... Keep your glasses clean kids!

    After (adjusted)

    Surface ~12cm (highest) : 347
    Sand back ~55cm : 81
    Sand front : 94
    SPS left: 241
    SPS right: 281
    LPS area left: 136
    LPS area right: 129
    Far right corner: 89
    Far left corner (lowest): 78

    I am going to retest again after it gets dark. The front part of the tank gets a lot of indirect sunlight.

    I am going to repeat the same experiment with my 150W MH on Thursday but will be changing bulb brands in that test from ColorMax 14K to Elos 14K so it is not quite as controlled an experiment.
     
  7. bondolo

    bondolo Supporting Member

    I will have completed my testing by Friday and can transfer the meter to Mark Rygh over the weekend or next week.
     
  8. BAYMAC

    BAYMAC Guest

    Par indeed does change with age. That is exactly how bulb changes are down on large farms.
     
  9. rygh

    rygh Supporting Member

    Apogee MQ-200 PAR meter results.
    Posted both here and in my LED build thread.
    Thanks BAR for getting one for the club!!
    Pure LED lighting, meter set to "sun" mode.

    For normal mid-day setting:
    (Left / Right)
    2 inches = 100-250 / 100-220
    6 inches = 150-180 / 130 - 150
    12 inches = 130-150 / 80-120
    24 inces = 60-90 / 50-70

    It is interesting that left is that much brighter. The difference is that the LEDs on
    the left side each have a short 1" PVC around them, as a "reflector lens" of sorts.
    I think I might tweak the right side up a bit.

    Most of my hard corals are at the 12 inch depth.

    The very front is quite a bit lower PAR. Around 80-90 at 12 inches.

    I also measured the LED fixture on "full power".
    I had to turn it down several times due to bleaching, so normal is a lot less.
    I only measured left side.

    2 inches = 270-350
    6 inches = 180-220
    12 inches = 180-220
    24 inches = 100-140

    So the fixture is capable of about 30% more than it is running.
    That is expected, due to settings.

    Note that the orientation of the sensor is pretty critical to measurement.
    It can be hard to get consistent readings.

    Just FYI, from updated code: Value = N/255, so 255=100% on.
    // left
    pwm_level_l_red = 136;
    pwm_level_l_rblue = 200;
    pwm_level_l_cwht = 180;
    pwm_level_l_nw = 255;

    // right
    pwm_level_r_red = 136;
    pwm_level_r_rblue = 230;
    pwm_level_r_cwht = 190;
    pwm_level_r_nw = 255;
     
  10. rygh

    rygh Supporting Member

    So anyone next on the list for the PAR meter?
    Post and PM.
    If not, I will keep it safe until the next meeting.
     
  11. rygh

    rygh Supporting Member

    Note:
    If you have an all-LED fixture, read this before trying to compare your PAR levels versus some MH or T5 setup!
    http://www.reefcentral.com/forums/blog.php?b=519

    As a rough estimate, he says to multiply up by 1.2X, but that all depends on ratios of blue/royal-blue/white/so on.
    Plus it was a slightly different meter.
    So a very large uncertainty. I don't really trust that number all that well.
    That 1.2 factor would put my PAR at coral depth at about 240.
     
  12. newhobby

    newhobby Guest

    So, is it in sun mode that we need to use this for LEDs??
    Now, what is a good range for SPS?
     
  13. RichieT

    RichieT Guest

    Is the meter still available? I'd like to see how well my single Kessil is lighting the tank. I'm considering buying a second, but wanted to make sure it was needed first.
     
  14. anderson99

    anderson99 Guest

    Shoot me a PM. I have one you can borrow.
     
  15. rygh

    rygh Supporting Member


    I still have the official BAR par meter.
    Pickup in Union City, or at next meeting, or somewhere in between us.
    PM me.
     
  16. xulio

    xulio Supporting Member

    I'd like to borrow the PAR meter. I'll be at next Saturday's meeting. Thanks.
     
  17. rygh

    rygh Supporting Member

    I plan to be at the meeting as well, and will bring the meter.
     
  18. xulio

    xulio Supporting Member

    Awesome. Thanks.
     
  19. sfsuphysics

    sfsuphysics Supporting Member

    Hmmm if I can swing the meeting maybe I'll just bring my LEDs and test it at the meeting... although it'd involve lots of disassembling... maybe not.
     
  20. pinner

    pinner Volunteer

    Id like to be put in line to use meter. Please pm me ill be at the meet this sat
     

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