I have two spider farm sf1000 which are 100 watt full spectrum LED. They’re almost touching in a daisy chain so I can grow two plants. They’re for a 2x3x5 tent.
Everyone mentioned the Photone app to get an accurate reading of ppfd and DLI. When I opened the app (because I have an iPhone) it suggested I purchase a diffuser and cosine corrector, so I did and it just arrived today. I placed the thing over my front facing camera and read a crazyyy high number. Which was odd because I was in the parameters of chart for the lights on this chart.
I have the full spectrum led option selected in app and lens is clean. Please help I’m a little confused as to why the light intensity is so low but numbers are right. I think maybe it’s because the lights are complimenting one another and possibly running 60% with the two 30%’s?
Now I’m conflicted because I’ve seen many people mention to get the app on this site and others. I paid for the full led section of the app and the light diffuser. I’ll have to hear more opinions against it before I accept defeat lol.
Low has done a fair amount of work and research on lights just saying, he’s got a voice you can trust. The manufacturer says their optimum tests rank way lower.
My two cents is an app on a phone might give you a ballpark representation, but it doesn’t put you on home plate. Meaning it will help but don’t expect it to 100% a true light meter may help…
Yeah I just spent money so was holding on to someone coming and saying that it’s accurate. Tough lessons when beginning a new hobby, @Low thank you for your advice. Are all par meters accurate or is there a brand to stay away from? I’m already set back $35 with this so wasn’t trying spend too much.
I paid for the led version also. The problem is that readings vary from phone to phone. No joke. Could even be the same model phone and they will be different readings. I just so happen to have a couple sf1000’s not in use and I will happily take some readings for you using a meter.
When I compared photone to the meter on my phone at the time…
I can only comment on the one I use (photobio) and apogee. Mine is the budget version and is damn near as accurate as apogee for a fraction of the cost.
I really appreciate you taking the time to do that, I’ve been sitting here for a while now thinking it makes no sense when there’s all these charts already.
For the time being because I would have to wait to get the reader. could you tell me what setting I should set my intensity and height at for my setup with two plants? It just my smallest one is the same age and looks like it may be light bleached but I’m first time grower so I wouldn’t know.
I can definitely do that tomorrow. The lights are currently sitting a “sleeping” tent. Unfortunately where I tune my dial will be different from yours because wattages on light fixtures vary from light to light. Total wattage is “tuned” on the controllers. So fixtures aren’t the same across the board. (Messed up, right?) So my measurements will put you in the ballpark, but not 100% accurate. If turn them up 100% that will get me within 10-15 watts of yours at 100%.
Just tell me the heights/ppfd you are looking for and I’ll do my best.
Oh I thought you just took that. In your experience with them and because you run two daisy chained how close is the recommended chart that I posted above? With one I would be more certain but not sure how another one close affects. I know you said there are different factors but ballpark is better than where I’m at lol
Tests also have variances, and often times the fixtures are overclocked for said tests… I even have caught HLG doing this, but at least they were honest with the wattage of the fixtures being tested. Other businesses don’t do this. the representation of numbers on the chart may be a little different from home. And tests can be influenced by many things. With that said, without a meter it’s ok to trust those charts.
The levels here are generally where you start from and what you work your way up to. However within those ranges some plants may behave better or worse in the same conditions. Believe it or not some are more picky than others. Not to mention environmental factors have an impact on how well those plants utilize the light levels. There are a lot of factors that can influence your plants behaviors and reactions to light levels. My recommendation, keep your nutrients simple. Keep your medium numbers in check, and learn how your plants react to light levels.
Big fan of take the info in, adjust your setup and then check your plants for the first 2-6-12-18 hours.
Did a ton of reading on my scorpion diablo, upped my light to %80 percent at 18 inches burned the tops in the first 6 hours. Caught it quick and adjusted, tiny amount of damage. Would have been a lot worse if I had waited till the next day to check. A quick drop to %70 and they were super happy.
Simple moves with a bit of upfront care and monitoring go a long way.
Can only agree with the assessment of Photone, the difference between the two phones i use can often be in the hundreds, which is kinda awful if you actually went by it when growing.
I only use it to identify areas where the intensity is dropping off in my space but i would never take the actual numbers for what it is
“PPFD Meter” on googleplay. Free app, best I have found for android. I have a samsung phone and you dont need a diffuser. Here are the screen shots of the app. Has alot of settings, multiple light sources, change the hours and set min max values that change colors for being out of your range.
Please don’t take this the wrong way, but you don’t need a light meter. Your grow and investment is small, and dli/recommended ppfd levels are baseline recommendations. I understand that you want to do things right and be as good as possible, but just use the free readily available reference materials and tweak as needed from there.
If you get to running a large grow or doing specific research this stuff starts to matter more. Then the accuracy is important and justifies spending more time and money on things like this.
I took this the right way and really appreciate you saying that. Got discouraged having to buy something that cost more than my grow tent/ lights combined.
