Calling all PAR meter owners - what's your outside PAR max reading for your area

LoveBudz420

Active Member
If you have a good quality PAR meter, and you know and/or you can measure your PAR outside at midday or whenever is brightest, can you please tell me how many PAR you get, outside, on a clear sunny day? I'm not looking for guesses, I'm looking for data. I have a good Apogee meter myself and I know my local PAR reading.

If you can tell me kinda roughly where you are, or roughly what latitude you're on... this would be nice data, but I know lots of paranoid guys are now eyeing me off like I work for the NSA or something... haha, your PAR with or without very broad location data is fine folks.

Thanks.
 
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LoveBudz420

Active Member
1500μMol/m2/s at high noon

Heres my location


Dropped pin
That is fascinating to me, even though I suspect the location data is not entirely accurate.

Did you ever use a meter to work out a DLI for your location? Rather than taking 1500μMol/m2/s and fudging around with the maths to work out an approx DLI.

Thank you very much for the feedback. I do not need many data points to "blow my mind". So far my mind is already blown from just one data point hahahaha.
 

Delps8

Well-Known Member
If you have a good quality PAR meter, and you know and/or you can measure your PAR outside at midday or whenever is brightest, can you please tell me how many PAR you get, outside, on a clear sunny day? I'm not looking for guesses, I'm looking for data. I have a good Apogee meter myself and I know my local PAR reading.

If you can tell me kinda roughly where you are, or roughly what latitude you're on... this would be nice data, but I know lots of paranoid guys are now eyeing me off like I work for the NSA or something... haha, your PAR with or without very broad location data is fine folks.

Thanks.
I'm in Orange County in Southern California and, IIRC, I got a reading of 206x on June 21.

You can use this page or, if you have an iPhone, go to the App Store and download the ClearSky app. If you plug in lat and long, the apps will give you info about max PPFD.
 
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Moflow

Well-Known Member
Some different par readings being posted.
Pictures or it didn't happen...... lol

I'm at 55°N latitude. UK
Highest reading for sunlight I've took on an apopee meter was ~2450 umols. Around midday, around the 21st June.
I can't find the picture I took that day at the moment though.
Fortunately that amount of sunlight is a rarity here, once a cloud blocks the sun the number drops dramatically lol
And we get a lot of clouds!
I hope that helps.

Here's the Sun 24th June 16.04 pm
20180630_121143.jpg


Outside at 55°N June 5th Cloudy. 13.42 hrs
20200604_134257-1-1.jpg20200604_134039-1.jpg
 

LoveBudz420

Active Member
Highest reading for sunlight I've took on an apopee meter was ~2450 umols.
Ok, that's a bit more like it!

I'm in Thailand, and first midday read was ~2550. But my overcast is more like a 500, and my overcast seemed thinner and more even; maybe even makes a better filter... I should have paid more attention to cloud class in school.
 

bk78

Well-Known Member
Ok, that's a bit more like it!

I'm in Thailand, and first midday read was ~2550. But my overcast is more like a 500, and my overcast seemed thinner and more even; maybe even makes a better filter... I should have paid more attention to cloud class in school.
Can you post pics of your 2550 midday readings?
 

LoveBudz420

Active Member
Can you post pics of your 2550 midday readings?
Next time it stops raining I will for sure take a snap of my 2550.

I wonder if it's the fact that I am using an Apogee MQ-610 compared to other people taking readings with the previous generation Apogee, or god forbid........... a non Apogee meter! (jk, i see there are some good meters for cheaper than Apogee, but I like Bruce Bugbee's lectures, so i supported him by buying Apogee).

I'm at 8° N

So we have short ass days. and where I live, it rains for 8 months of the year, but that means I get ~2550 for 4 months without rain, and those 4 months are in a row (in theory). Will have to be Auto only grows or veg inside and bring outside.... because our dry weather is from December to March and Thailand is in the northern hemisphere.
 
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Horselover fat

Well-Known Member
If you have a good quality PAR meter, and you know and/or you can measure your PAR outside at midday or whenever is brightest, can you please tell me how many PAR you get, outside, on a clear sunny day? I'm not looking for guesses, I'm looking for data. I have a good Apogee meter myself and I know my local PAR reading.

What are you trying to achieve? DLI info is available from around the world.
 

LeastExpectedGrower

Well-Known Member
Nov 2.2 dli, Dec 0.89 dli and jan 1.53 dli here.
It appears to really just be a calculation of sun angle + daylight time in a region and not account for cloud-cover or precipitation. Our microclimate gets an extra foot or two of snow than the the region, so I'd suspect ours is closer to the numbers you list. Would be an interesting experiment to log and track this across a year with multiple daily readings.
 

Horselover fat

Well-Known Member
^ you are right about it being calculated, but I think they are at least trying to account for cloud cover.

"It uses worldwide weather station data, satellite data, and algorithms to deliver the most accurate DLI values for your location."
 

LeastExpectedGrower

Well-Known Member
^ you are right about it being calculated, but I think they are at least trying to account for cloud cover.

"It uses worldwide weather station data, satellite data, and algorithms to deliver the most accurate DLI values for your location."
Yeah, I looked at the 'weather stations' in my area (neither of which are in our micro-climate), then I pulled the map out pretty far and realized it really is just large bands that match latitude.
 
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