Good post. I was v nervous about frying my plants and v gradually increased the power on my xs2500pro.
Can't believe they're posting 2 different par maps. That's confusing as hell.
Bottom line is i'm now more sceptical than ever about broscience 420 forum posts.
I have a few wks till finish and it's a nervey time.
"Just dont F it up" mantra.
Looking forward to being able to put a proper evidenced report on the xs2500pro.
Thanks
HH
I'm skeptical, by nature, but you're taking it to another level.
"Good post. I was v nervous about frying my plants and v gradually increased the power on my xs2500pro.
It's very hard to damage a plant using an LED grow light. It takes "a high level of unfamiliarity", to be kind, or negligence. HPS lights generate a lot of heat and, if a grower wasn't attentive, the heat could rapidly cause tissue death. In contrast, an LED produces very little heat. A typical description is that they're "warm to the touch". I've seen pictures of plants touching LED bars and there's no tissue damage.
What about harm to the plant caused by excess light? Not easy to do, ref. my comment above. I had a dimmer fail in a 330 watt light. The plant was at 1100±µmol and the dimmer went out, so the plant was at 1350 or so. The only way I caught it is that the temperature reading on the AC Infinity Controller 69 went up and I happened to see it. When I walked into the garage, I could see the blaze of light. Fortunately, I had a spare dimmer so I swapped in the good dimmer. The plant had done what was completely normal when a cannabis plant gets excess light - it reduced the surface area exposed to the light by "canoeing". After turning the light down, the leaves started "unfolding" and were at their normal shape with in an hour of so.
I grow in high light conditions and I'd have to say that I probably turn it up too fast every other grow or so. No big deal. When the plant reacts, either by canoeing/tacoing or rotating the leave toward the vertical, as if it were a Venetian blind, you just turn the light down a bit/raise the light an inch.
The worst I've ever done was to bend a cola. The cola bent at a slight angle and stayed that way when I turned the light down.
Growers lose more yield by not turning their light up high enough than the do by turning up their lights too high. Per the paper, "Frontiers in Plant Science - Yield, Potency, and Photosynthesis in Increasing Light Levels", crop yield increase about 4% for each 50µmol of PPFD.
If your grow isn't in the 900-1000µmol region, which is a light level where cannabis thrives in ambient CO2, you can calculate the amount of your crop that you're not getting.
"Can't believe they're posting 2 different par maps. That's confusing as hell."
Those PPFD maps are different because those are different lights. The new model has a lower PPFD, just like I explained in the text. And there are valid reasons for Vipar to make the change, just like I explained in the text.
"Bottom line is i'm now more sceptical than ever about broscience 420 forum posts."
I don't know why you say that but, if there are things you don't understand, ask away. There's a lot of expertise on RIU.
"I have a few wks till finish and it's a nervey time."
No need to be nervous but each to their own. One thing that I got a kick out of when I joined RIU was the acronym "LTFA". If conditions in your grow are decent, you'll get a good crop.
"Looking forward to being able to put a proper evidenced report on the xs2500pro."
You've said similar things in other postings and I'm not sure what you want. A grow light has a limited number of characteristics and the marketing literature covers the big pieces. The 2500 has a blue heavy spectrum so it will tend to grow plants that are compact and bushy. It has a good PPFD map so the light can generate a pretty high yield. The driver isn't dismountable and it's a board light so it's going to heat the grow area a little more than a bar style light with a dismountable driver.
Since you're already using the light, what are you expecting or hoping to learn from a review?