Par meter for under 500 but over 100

B

budman410

Well-Known Member
I’m done being cheap, couldn’t bring myself to use the apps or buy a cheapo lux meter. Right now I only have white leds between 3k-4k. But I will have my reds/and later different color leds on my boards
 
Galaxyhydro was cheapish and did the job. It comvinced my growbuddy that led would be enough light. It measured great par levels on the first big build. And then promptly broke, partly cause my buddy can be a tool when it come to taking care of stuff. A good lux meter with settings for electric light and higher than 50K lux max does fine. If your adding reds and uv/violets just do it buy % of watts.
 
Rocket Soul said:
Galaxyhydro was cheapish and did the job. It comvinced my growbuddy that led would be enough light. It measured great par levels on the first big build. And then promptly broke, partly cause my buddy can be a tool when it come to taking care of stuff. A good lux meter with settings for electric light and higher than 50K lux max does fine. If your adding reds and uv/violets just do it buy % of watts.
Click to expand...
Was it the one that’s 350... I mean did he break it or it’s just cheap. It just seemed like a lot of math and calculating when using lux meters. And I’ll need to dial in different areas and tables. And may change depending on the season
 
There is a guy who has tested and made public his cheap lux reading meter compared to an expensive Par meter under various leading LED lights. I'm sure you can google it. But if it's apples to apples I don't see why you wouldn't be able to trust the results with the same cheap Lux meter he used.
 
DaFreak said:
Because I am such a nice person I went and found the video I saw


Check this out. $30 calibrated to par meter
Click to expand...

Wow this is so helpful thank you! The thing I am not understanding is if I do 40,000 Lux x 0.23 I come up with 9,200? Do I need to then divide the umols / square meters or something of my closet/tent? Not seeing how I get to the 0-1000 PAR value.
 
I just saw in the comments of the video he was off by a decimal place. Makes way more sense now. So we can just use the following to calculate
  • 3000K - Lux x 0.023 = PAR
  • 3500K - Lux x 0.022 = PAR
  • 4000K - Lux x 0.024 = PAR
Originally I was using this guide from RQS > https://www.royalqueenseeds.com/blog-how-to-use-a-lux-meter-to-increase-your-cannabis-yields-n977

I also tried using the HLG converter to figure out PAR but since I have the v1 lumiled qb288's i wasn't sure how accurate that was using the V2 board calculations. I came around to figuring out my proper lux levels (which is like 40-50K max) by just experimenting with it in over a few rounds. Before I was trying to push to 65-70K lux based on the RQS article and I realize now that while the light didn't burn my plants it was stressing them way too hard and affecting yields. Eventually I figured I would back them way off and see how they did, and they have been much happier.
 
If your lux meter is reliable (which is cheaper than a par meter) then usually approx: 10000lux is about 150ppfd. Edit: maybe need to check my numbers...

I think re the galaxy: a bit of both. Cheapish and my buddy derp broke it. It convinced him to go led which has made back all the money
 
Last edited:
ilovereggae said:
I just saw in the comments of the video he was off by a decimal place. Makes way more sense now. So we can just use the following to calculate
  • 3000K - Lux x 0.023 = PAR
  • 3500K - Lux x 0.022 = PAR
  • 4000K - Lux x 0.024 = PAR
Click to expand...

That's why I like to divide:
  • 3000K - Lux / 43 = PAR
  • 3500K - Lux / 45 = PAR
  • 4000K - Lux / 42 = PAR
Less typing and easier to remember.

To be honest you might as well divide by 44 (as an average) since it doesn't matter all that much anyway because these things are massively inaccurate
 
Since I been using led I’ve been measuring my lights based off wattage sq, how plants react, and my experience. With the margin of error a lux meter may have. It should still be able to work for me and figuring out if I’m not using too much wattage. That’s the issue I’m circling around now I feel like I’m giving clones and my sog to excessive light essentially wasting wattage
 
That's why I would find it hard to spend anything over $30 on something that plants can tell me for free. But this is a hobby and we don't really need excuses to spend money on a hobby, just can't imagine it would make me change anything.
 
So as a test I held my cheap lux meter 18 inches under the center of my grow tent and using the conversation above got 1,172. Interestingly enough the data from timber lights where I bought my 3500k COB lights says that it is 1245 right in the center. I don't know about the rest of you, but I think that is pretty damn close, only off by 70. Now the numbers jump up and down and was only holding it by hand so maybe it is closer. But it seems like if you are in the 45k to 53k Lux range you should be more than good.
 
DaFreak said:
Because I am such a nice person I went and found the video I saw


Check this out. $30 calibrated to par meter
Click to expand...

Dude you rule! I have that exact lux meter ($30 CAD) and was about to drop $830 CAD on that Apogee SQ-500.

Oh yeah! :bigjoint:
 
DaFreak said:
That’s the replacement sensor for one.
Click to expand...

I think he’s saying hook up the sensor to a volt meter. Ie: you don’t need the whole unit, the volt meter acts as the display.

I’m confused though if this is the case. 800 volts = 800 par???? Can’t be that simple. Must have to use some kind of chart or conversion factor.

@SupraSPL can you explain further?
 
DaFreak said:
That's why I would find it hard to spend anything over $30 on something that plants can tell me for free. But this is a hobby and we don't really need excuses to spend money on a hobby, just can't imagine it would make me change anything.
Click to expand...
This is one of the few hobbies you actually end up saving hundreds to thousands depending on how much you smoke. I’m surprised more people aren’t less frugal..BUT if you just have a tent or 2 I wouldn’t think a 500 meter would be worth it. My situation a little different, when I’m finished in my other space I’ll have 14 4x4 flood tables and 2 veg rooms. Wasting watts add up over time.I grow year round and the only down time is cleaning in between cycles, which now is going to be cut down some more now that I have this ozone generator. Since I switched over to Leds I’ve been getting over the learning curve and how my grow techniques and light spacing should change. I’m fairly sure I’ve been giving them more then enough and that’s an issue. Between flowering mothers and clone sogs it’s hard for me to figure out how intense I should make the lights or dedicate side lighting for my flowering mothers. I flower some out every new cycle
 
You must log in or register to reply here.

Similar threads

B
Cheap LUX meter to calculate PAR and DLI
2
Replies
26
Views
2K
Rennpappe
Rennpappe
pegboy
Recommendation: Cheap PPFD meter?
2 3 4
Replies
64
Views
5K
bobbjoedope
B
GemGrows24
Please Help! First timer /stunted growth/yellow leaves
Replies
9
Views
767
bignugs68
bignugs68
chamenon
Can I combine a blurple with a 5000k LED for flowering?
2
Replies
37
Views
3K
Er3
Er3
E
CaMg issues after some improvements maybe?
Replies
3
Views
629
etc2003
E
Back
Top