Par Multiplier Thread

Stephenj37826

Stephenj37826

Well-Known Member
This thread will have an ever expanding list of Par multipliers that will effectively negate the need to calculate LER/QER

Cree COB 3000K 80 CRI 0.014471
Cree COB 3500K 80 CRI 0.014240
Citizen COB 3000K 80 CRI 0.014415
Citizen COB 3000K 90 CRI 0.016079
Samsung 561C 3000K 80 CRI 0.014505
 
Stephenj37826

Stephenj37826

Well-Known Member
No multiply this by lux or lumens per watt estimate to get umols / umol/j

Example 3500K Cree if estimated to get 10000 lumens you would multiply 10000X.014240 and you would have a PPFD of 142 umol/m2sec

Or if for example 3500K Cree the estimate is 140 lm/ watt 140X.014240 or 1.9936 umol/j
 
BuddyColas

BuddyColas

Well-Known Member
Stephenj37826 said:
This thread will have an ever expanding list of Par multipliers that will effectively negate the need to calculate LER/QER

Cree COB 3000K 80 CRI 0.014471
Cree COB 3500K 80 CRI 0.014240
Citizen COB 3000K 80 CRI 0.014415
Citizen COB 3000K 90 CRI 0.016079
Samsung 561C 3000K 80 CRI 0.014505
Click to expand...
Very useful. I like easy ball-park tools. I'm not going to obsess over a photon or two. Thanks.
 
Abiqua

Abiqua

Well-Known Member
Umm can you provide the conversion for radiant watts /m^2 .......j/K

Dammit now I gotta find and fire up the Arduino and see if this correlates eh? :peace:
 
Danielson999

Danielson999

Well-Known Member
Evil-Mobo said:
Anyone in particular you recommend on android? Would be cool just to compare the LED and HPS sides............
Click to expand...
I have only tried one (Lux Meter on google play) and it works good but it max's out at 30000lx. I haven't had the time yet to buy the premium version for $1 but hopefully it allows higher limits. I guess I should get on that one of these days. Tonight is Thursday night football so can't see it happening :)
 
welight

welight

Well-Known Member
Can it really be Lux or Lumens? they are totally different measures? I assume it is based on the ratio of 1 lux =1 Lumen per square meter?
Cheers
Mark
 
Stephenj37826

Stephenj37826

Well-Known Member
welight said:
Can it really be Lux or Lumens? they are totally different measures? I assume it is based on the ratio of 1 lux =1 Lumen per square meter?
Cheers
Mark
Click to expand...
Yes it can be lol.

In one instance you are converting a spot measurement(lux) to a spot measurement (ppfd)

In the second case you are converting a total output(lumens) to a total output(ppf)

I.E. 3000K Cree
The most accepted Ler/Qer is 325/4.66 correct?

Math 4.66/325 = .0143384 vs spot reading above of .014471

This small reading difference could be due to buy not limited to the following ( chromatic binning , optics, atmospheric conditions (dust) limitations of measuring device (Lighting Passport) so on so forth.


One figure comes from calculated lumens and calculated photon count
The other comes from measured lux and measured ppfd.

So yes the multiplier is universal between lumens(total output) and lux (intensity measurement of lumens in a defined area)
 
MarCus M.D

MarCus M.D

Well-Known Member
So...
12 * 48,85W (cxb3590 1400mA) = 586,2W.

Cree COB 3500K 80 CRI 0.014240 * 182.54 lm/watt

586,2 * 2.5993696 = ~1523 PPDF...... For 1,2x1.2mt, is that correct?
 
wietefras

wietefras

Well-Known Member
Stephenj37826 said:
This thread will have an ever expanding list of Par multipliers that will effectively negate the need to calculate LER/QER

Cree COB 3000K 80 CRI 0.014471
Cree COB 3500K 80 CRI 0.014240
Citizen COB 3000K 80 CRI 0.014415
Citizen COB 3000K 90 CRI 0.016079
Samsung 561C 3000K 80 CRI 0.014505
Click to expand...
How about a PAR divider for better readability and while we're at, use less decimals since these things aren't that precise anyway?:
Cree COB 3000K 80 CRI 69.1
Cree COB 3500K 80 CRI 70.2
Citizen COB 3000K 80 CRI 69.4
Citizen COB 3000K 90 CRI 62.2
Samsung 561C 3000K 80 CRI 68.9

Apogee calls this PPF to Lux (technically to lumen I guess but hey): http://www.apogeeinstruments.co.uk/conversion-ppf-to-lux/

BTW other data found here says Cree 3000K 80 CRI has a LER of 325 and a QER of 4.85 which makes it 325/4.85=67. While for Citizen 3000K 80CRI it's supposed to be 328/4.86=67.5
 
Stephenj37826

Stephenj37826

Well-Known Member
MarCus M.D said:
So...
12 * 48,85W (cxb3590 1400mA) = 586,2W.

Cree COB 3500K 80 CRI 0.014240 * 182.54 lm/watt

586,2 * 2.5993696 = ~1523 PPDF...... For 1,2x1.2mt, is that correct?
Click to expand...

It would be but those numbers are out dated. Here is sphere data from 3000k and 4000k so between these two

Screenshot_20161127-135622.png
 
Stephenj37826

Stephenj37826

Well-Known Member
wietefras said:
How about a PAR divider for better readability and while we're at, use less decimals since these things aren't that precise anyway?:
Cree COB 3000K 80 CRI 69.1
Cree COB 3500K 80 CRI 70.2
Citizen COB 3000K 80 CRI 69.4
Citizen COB 3000K 90 CRI 62.2
Samsung 561C 3000K 80 CRI 68.9

Apogee calls this PPF to Lux (technically to lumen I guess but hey): http://www.apogeeinstruments.co.uk/conversion-ppf-to-lux/

BTW other data found here says Cree 3000K 80 CRI has a LER of 325 and a QER of 4.85 which makes it 325/4.85=67. While for Citizen 3000K 80CRI it's supposed to be 328/4.86=67.5
Click to expand...

4.85 counts outside of 400-700 nm which isn't technically par :)
 
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