I am curious to find out the type of meter to use, there are a lot of meters out there, how do I know which one is the right ones to get or use. Also, do you buy a meter, rent a meter, what? Info would be helpful and appreciated, oh so very much! I have searched, and I am getting confused and agitated, no frustrated, is there a difference? I need a weed break, now! Until we meet again!
regards,
Depending on how accurate you want it, there are some apps for your phone you can download for free to measure.
Apogee mq-500 is pricey but definitely worth it. Especially if you have LEDs and need to figure out the perfect height to hang your lights.
You could probably get away with a lux meter if using other types of lighting but I have a feeling they arenât the most accurate.
A par meter is what measures the energy to the plants, most others measure what our eyes see, which isnât always the most accurate info your looking for.
Hereâs a great guide on light meters by a well know redditor.
Should help you with the info youâre looking for
https://www.reddit.com/r/HandsOnComplexity/comments/17nxpy/using_a_lux_meter_as_a_plant_light_meter/
this is some real good information, thank you, very interesting.
regards,
Par / ppfd is whatâs best, lux / lumen is allot less expensive. I think for me having something thatâs repeatable is whatâs key. This way I know in my room that this many xxxx give me this result.
I use a lux / lumens meter because Iâm cheap.
Yes, PAR meters are much more expensive. For the relevant data, if you know your light source is acceptable, using it to replicate the intensity when playing with height and wattage is very helpful.
Great link @invisible!! 
Thanx & cheers
G
Cheap lux meters are helpful really only in measuring relative intensity. There is too much variance among them, and their measured spectrum is too narrow (visible light, rather than photosynthetically active light or PAR) for accurate comparative analysis across devices and users.
That said, a cheap lux meter or phone app is helpful in understanding approximate intensity across the canopy with different light sources and design configurations, especially in finding low-light and hot spots. You are looking for 20-30K lux for veg, and 40-50K for bloom spaces, with white LEDs (doesnât work with blurple). The human eye simply maxâs out at perceiving differences in intensity those levels, so a light meter is definitely useful.
Only a PAR meter will measure the total intensity of plant-usable light available. With all horticultural lighting, but especially with premium LED, the difference between lux and PAR (technically, PPFD) can be dramatic. If you are spending more than $1200-1500 on your light system, you should probably be thinking about grabbing a simple PAR meter.
The Apogee 500 is what I use, you can get the version that plugs into a laptop or iPad for under $400 with some looking. But for personal gardeners, Hydrofarm makes a much cheaper and less accurate PAR meter that you can find for under $150. Yeah, itâs plastic, and consistently under-measures by 7-10%, but itâs a pretty good compromise between a basic lux meter and the Apogee.
Yeah It helped me a lot with understanding LED light as I was coming inside from the outside and had no idea about it at all.
yeah, I grow for medicinal needs. I want to grow a real good quality bud for my family and me, well mainly me. Hold on there Crickett, before you jump to conclusions. Iâm the one taking care of the plants, so naturally I want them to be as good as I can get them, within reason that is. So, a $1,200.00 meter is way out of the realms of possibilities for me. I didnât have a clue meters were that expensive. Maybe, I can check on renting a meter, then again, that might not do any good just measuring it a time or two. I donât know? But, thanks for all of the information, It gives me something to think about.
regards,
I have seen PAR meters for rent on kijiji
Probably more important for HID and fluoro lighting, the bulbs slowly deteriorating.
Way back I was told and read they should be changed after 6 months or so, probably incorrect.
In a larger operation you would make savings not replacing dozens of 50$ bulbs without good reason.
You could map PAR and distance to lamp in your situation, check out how an older vs fresh bulb behaves. Measurements that will be true later on as well.
Me, I just stick my head in the grow, that and use the Lux meter on my multimeter. Cant justify the expense.
Just to clarify, I did not suggest that anyone spend $1200 on a PAR meter. I said a good quality meter can be had for under $400, and a less expensive option is available for under $150.
I understand brother, I may have gone for the âoverboardâ price point. but, weâre just poor church mice here. when you are disabled, well, lets just say, things do not come as easy as they use to. but I really do appreciate the information.
regards,
Where are 150$ par meters?
Looks like theyâve discontinued the model I picked up, replaced by the âPHOTOBIOâ at suggested price of $199. Here it is online for $167.
https://www.xglobalsupply.com/products/photobio-advanced-quantum-par-meter
Thanks , I may grab one.
PAR meters measure all the light from 400 - 700nm but ignore light outside that range that is still useful for the plantâs growth. Also itâs just certain frequencies in that range that are useful for plants but a PAR meter measures them all to get itâs score. So you might have a light that blasts lots of PAR light that is useless to the plant.
For years now Iâve just uset the light setting on one of those cheapo 3-function plant probes. The do moisture, light and pH. The pH part is totally useless and the Moisture setting is iffy but can tell you that itâs still wet 6" down in the pot so donât bother watering yet.
The Light setting only shows the intensity of the light on a scale of 0 - 2000 and doesnât even say what the units are. This is still very useful information and helps with placement of plants that need different levels of light for their stage of growth. Or like I did with 3 different brands of HPS grow lights. Ran an experiment to see which was giving me the most bang for my buck. I ran each light and tested the intensity at 1 - 2 and 3 ft from the light and recorded the levels. Surprised me.
The best part of it is the damn things only cost around $10 at any garden centre. I figure thatâs good enough for my needs.
Good explanation HERE about PAR light.
PS: I tried a couple of those âFreeâ light meters you can use with your phone and found them useless. They only read up to a fairly low intensity unless you pay for them and I did not find them useful at all.
PPS: Just stumbled on this Reddit post that goes into all sorts of detail about measuring light this guy recommends a simple $20 lux meter for most home growers.
