LED and BUD QUALITY

[smirnoff420]

Has anyone attempted a virtual grow with LEDs? I'm tempted to arnage my strips in a 1.5 m high configuration either square /pentagon/hexagon would give me either 600w/ 750w or 900w fixture growing on 3 walls giving me a surface area of 6.75m2

Yes, but only in small cabinets around 0.5m²

 

[smirnoff420]

Regarding square or hex tubes, this is a radiation angle diagram of Samsung LM301B LEDs.

Square would mean 360/4=90 degrees. So -45 and +45 in the diagram or roughly 70% of light at the edges worstcase compared to center.

Hexagon would mean around 85-90%.

 

[Ca++]

@JKD
Extra cost, but a rotating light mover you wouldn’t need the hex LED. Hang your LED vertically from the centre hook. Gives the option also of using the arms and hanging another LED for the outside of your vertical scrog. Otherwise, don’t attach them. View attachment 19085366


There is a difficult to achieve stretch avoidance technique, where the tops are brushed regularly. Perhaps if these arms reached out as far as the plants, then a weighted line could be dropped. Said line, would brush anything getting into the zone. Helping with training.

I would have to try, if using such a thing. I also see your idea of just lights in the middle. The QBs and others, have screw holes for eye bolts. They would easy hang from each-other, with the obligatory cable ties.

 

[smirnoff420]

I recently added 6500k LEDs to combat stretch. Will see in the next weeks how that goes.


Edit: Here is a pic where you can see the leds better.

7 stripes with 98x Bridgelux Thrive 4000K LEDs each vertical, around 700 LEDs

Ceiling is around 600 LEDs LM281B+ 3500K and 600 LEDs LM281B+ 6500K

Currently the 3500Ks at the ceiling are off.

 

[greyfader]

I grew vertically for many years in a 4x4 (1.2m x 1.2m) box that I built myself (before tents were all the rage) with 2x 600W HPS bare bulbs.

I do have an idea for a vertical LED setup, but it requires a hexagonal extrusion (tube). You could possibly do it with a square tube – with strips mounted to all four sides – but the light distribution/overlap is not as good as a hexagon.

There are hollow, hexagonal extrusions out there that I was planning to use, and so I would use a 1m-1.2m length with 2x 480mm High Light strips mounted end-to-end each side (12x total) and have active cooling (fan) on the floor blowing up, over the LEDS, as well as through the middle of hollow extrusion (PC fan possibly) to actively cool the heatsink.

By my calculation (based on previous experience), you need at least a 1.5' (45-50cm) diameter circle around the vertically hung LEDS as clearance, so the plants could grow about 20cm away. You would place a round tube trellis (a tube of fencing wire) around the vertical LEDS, and that would support the plants as they grew towards the LEDs. Then you simply weave the branches into the trellis – like a vertical scrog – and train the plants that way.

No need to turn the plants – they grow where the light is – and you end up with a canopy that grows around the LEDs and is much larger than the floor area of the tent.

A 1.5' diameter circle that is 5' high, for example, has a canopy surface area of (3.142 x 1.5 x 5 =) 23.5 sqft. A 4x4 tent has a floor area (nominal canopy surface area) of only 16 sqft.

Yes, it can be done!

View attachment 19085223

View attachment 19085224

View attachment 19085222

nice! i grew vertical trees for many years with the plants in a checkerboard pattern on 6 ft centers. i dropped a 1000 watt hortilux hps super vertically between each group of 4 plants, except for along the walls and corners, where i used 600 watt bulbs. this put at least 250 watts on every side of every plant.

i, too, used metal fencing encircling the plant as trellis.

with reflectix walls, almost all light produced will eventually be intercepted by plant material.

this worked in spaces like basements or two car garages with about 12 plants.

but for rooms with approx dimensions of 10x10ft , 10x12ft, 12x 12ft or so, the best arrangement i've used is the old heath robinson pattern.

this was 4 plants against the center of each wall with a single 1000 watt bulb hung vertically in the middle and 4 600's in the corners. 3600 total watts on four large plants.

this could be done with leds. the four sided extrusion would be ideal for the center position. and maybe the hexagonal extrusion with 3 sides lit for the corners.

one of the problems with vertically hung hps bare bulbs was that the sweet spot of the light came off the 10" long arc tube like a pineapple slice, radiately outward and only slightly fattening as it reached out.

this could be corrected with leds by making the vertical strips longer so that they hit a larger surface area of the plant simultaneously.

i used two vertical bulbs in each position for a while, one up and one down, suspended by chains. these would be flipped back and forth twice per period as in 3 hours low, 3 hours high, 3 hours low, 3 hours high.

this gave pretty good coverage for 6 ft upright plants.

 

[greyfader]

@JKD
Extra cost, but a rotating light mover you wouldn’t need the hex LED. Hang your LED vertically from the centre hook. Gives the option also of using the arms and hanging another LED for the outside of your vertical scrog. Otherwise, don’t attach them. View attachment 19085366


There is a difficult to achieve stretch avoidance technique, where the tops are brushed regularly. Perhaps if these arms reached out as far as the plants, then a weighted line could be dropped. Said line, would brush anything getting into the zone. Helping with training.

I would have to try, if using such a thing. I also see your idea of just lights in the middle. The QBs and others, have screw holes for eye bolts. They would easy hang from each-other, with the obligatory cable ties.

i suspected you were one of those thigmotropic fellows!