Apogee 510 Reading question, Help.

[Steverd]

I just got an Apogee MQ-510 from BRS.
Put the battery and and starting taking measurements.
Is the number readout the PAR value?
I am wondering, because the manual mentions: PAR, PPFD, PPF
So what is this 256 reading I see?
Does this mean my PAR is 256?
Well my SenEye was reading about 100-120 PAR in the same spot?
What is going on?

 

[P-Dub]

Essentially they are all, more or less, the same. See the following and read the 'Introduction'. https://s3.amazonaws.com/brsinstructions/Apogee/SQ-520.pdf
256 is the PAR or more precisely, µmol m-2 s-1. So, yes, your PAR at that reading location within the tank is 256. The reason the difference in readings is the Seneye is just not the same caliber piece of equipment as the Apogee.

 

[Steverd]

So, yes, your PAR at that reading location within the tank is 256. The reason the difference in readings is the Apogee is just not the same caliber piece of equipment.

The Apogee or Seneye is not the same caliber of equipment?
Trust the Apogee or trust the Seneye?

Thank you

 

[P-Dub]

The Apogee or Seneye is not the same caliber of equipment?
Trust the Apogee or trust the Seneye?

Thank you

Sorry for any confusion. Corrected... The reason the difference in readings is the Seneye is just not the same caliber piece of equipment as the Apogee. Trust the Apogee...

 

[JCTReefer]

You will love the meter! I've used mine quite a bit over the last few months. It does time out a little too quick for me, but no big deal really. The optional fiberglass wand is pretty handy also. Really is a must running LEDS... I found it on sale at Premium aquatics for 440.00 Was the cheapest I could find it. After watching the Brs videos I decided on this meter. I've heard Apogee has good customer service also. I normally just take real time measurments. I haven't messed with any of the other features. Just simply take measurements and make notes. Enjoy!

 

[oreo54]

Essentially they are all, more or less, the same.

They are not the same..but they are used the same..

PPFD is not PAR though people incorrectly call it PAR..

sorry pet peeve..

PAR is a much used (and often misused) term related to horticulture lighting. PAR is NOT a measurement or “metric” like feet, inches or kilos. Rather, it defines the type of light needed to support photosynthesis.

PAR is photosynthectically active radiation w/ actually no "metrics"..


PPF photon flux call it PAR/sec .. actually (μmol/s)

PPF is photosynthetic photon flux. PPF measures the total amount of PAR that is produced by a lighting system each second.

PPFD "PAR" /meter squared/sec (μmol/m2/s)

The meter measures PPFD..and people just say PAR..
https://fluence.science/science/par-ppf-ppfd-dli/

As to the Seneye it's not cosine corrected as is the 510. Meaning it doesn't account for light in a large arc.
It's subject to a lot of "tilt" error so to speak..
also its spectrum reading isn't as "even" as the 510
All pretty well explained here though some will argue it"s "window" is smaller..i.e not the slightly greater than 90 shown.more like 60
https://www.seneye.com/light/par

So not not the same caliber as a 510..though there is quite a lot of evidence that it is generally pretty similar in response in real life.
Some of this will depend on light spectrum.. REAL heavy blue lights would generally be less accurate than a more balanced spectrum light..

 

[jda]

Yes, trust the Apogee. SenEye can get close if you mount it perfectly perpendicular and stop all water movement above it - even a slight tile can affect the values tremendously. The apogee just works no matter what with the cosine corrected sensor whereas the SenEye needs near perfect conditions.

The apogee also has any underwater factors applied to it already... if you use it out of water, then you need to divide by 1.32 to get the right value.

There is a BRS article on the Apogee 510 where they found an early issue. Early serial numbers will read low... and later serial numbers have the fix applied already.

In any case, look the graph for your sensor and understand what it does, and does not capture... the 510, for example, starts to fall off near 400, so if another meter does to 380 and you are using a mercury based source, then you might expect that other meter to read higher. You can overlay the spectrum from the source with the meter response and then do some fuzzy judgement in your head.

 

[P-Dub]

They are not the same..but they are used the same..

PPFD is not PAR though people incorrectly call it PAR..

sorry pet peeve..


PAR is photosynthectically active radiation w/ actually no "metrics"..


PPF photon flux call it PAR/sec .. actually (μmol/s)



PPFD "PAR" /meter squared/sec (μmol/m2/s)

The meter measures PPFD..and people just say PAR..

Essentially they are all, more or less, the same. See the following and read the 'Introduction'. https://s3.amazonaws.com/brsinstructions/Apogee/SQ-520.pdf
256 is the PAR or more precisely, µmol m-2 s-1...

So, for clarity, they are essentially, more or less, the same or more correctly, while perhaps incorrectly applied but still the same, for the sake of simplicity. But I do understand pet peeves though...;)

 

[saltyfilmfolks]

The seney has a “narrow eye” as it’s optical. And will “see “ less of the light.

Seems common.

Unfortunately.

 

[Steverd]

The seney has a “narrow eye” as it’s optical. And will “see “ less of the light.

Seems common.
Unfortunately.

Thank you, I need to make a video comparing the two, side-by-side in a tank.
My zoanthids were getting 250 PAR when I thought I had it at 100 (seneye reading).
-sigh-

 

[saltyfilmfolks]

Thank you, I need to make a video comparing the two, side-by-side in a tank.
My zoanthids were getting 250 PAR when I thought I had it at 100 (seneye reading).
-sigh-

And they were probably growing just fine too I imagine.

 

[Steverd]

And they were probably growing just fine too I imagine.

I have a few frags of Rastas that just would not open. They didn't open for two weeks.
Tested every parameter I could.
Now that I have my PAR in my zoanthis frag tank to 100, they have opened again.
I have to conclude they had too much light???

 

[jda]

I am growing Rastas right now under 500 PAR... they are in my frag tank and this is about as low as I can go. I don't keep a lot of Z&P, but BamBams, Rasta, Utter Chaos, Blue/Red Hornets are noxious weeds in my tanks under high-PAR halides.

This could be a quality thing and not quantity.

 

[Steverd]

I did make a video today to compare the readings of my Seneye Reef vs Apogee MQ-510.
The Thread is here if you have a few minutes:
https://www.reef2reef.com/threads/par-meter-battle-apogee-vs-seneye-reef.536927/

 

[oreo54]

Interesting but since you are about the first to show horrible variation you could have a defective unit.
Vid doesn't show anything that would cause it and, to be honest, you are not the first "independent" to do a side by side..

http://www.reefcentral.com/forums/showthread.php?t=2626700&highlight=seneye

 

[Steverd]

Interesting but since you are about the first to show horrible variation you could have a defective unit.
Vid doesn't show anything that would cause it and, to be honest, you are not the first "independent" to do a side by side..
http://www.reefcentral.com/forums/showthread.php?t=2626700&highlight=seneye

I've seen that post before, I would be happy if my results where close to that one.
I have messaged Seneye Customer report and hopefully will hear back from them soon.

Steve