HPS par values without reflector and with reflector ??

Hi,

Dose anyone have par ( or footcandels) values for hps WITHOUT reflector and WITH reflector ??

I am trying to figure out IF I wish to use reflecor and which one.

I have seen par and footcandel values for different reflectors but I have not seen values for same lamp without reflector (just basic tent or even without a tent) for same footprints. This would be important to get a grip on how effective the reflectors are .. if they are really ineffective I might try vertical scrogging which has its own can of worms ( not as easy / requires more attention ).

I am considering all orientations of lamp .. horisontal and vertical

using 400w and/or 600w hps.



Thank you for reading and links/info in advance!!

They all have a purpose. If you are using supplemental light in a greenhouse then the reflectors should be small to allow sunlight in. If you are growing in a grow tent than a large, flat reflector would be better suited to a flat, even canopy. Air cooled would help in a grow tent, but in a greenhouse air cooled would be more of a waste (just use fans).

There is a store with the name growers H, they do some studies like that. Different reflectors have much different scores. Raptor being one of the higher rated, although it's huge. Cool tubes having the lowest rating. Then again a cool tube can get much closer, depending on room temps (time of year and all that).

I think we are getting to a point in technology that totally different light styles are coming out.

But anyway, a bare bulb is going to be lower scores than a cool tube. Unless you grow vertical. Cause that too is a totally other style of growing.

And there are so many different areas in a grow to squeeze out a few more ounces. Some guys can pull amazing weight with a cool tube. Again it's strain dependent and not all strains that pull all that weight are going to be as catchy as a strain that pulls less.

Everything is getting more complicated. Many fine points, lot's of in's and out's.

Any HPS should be able to yield around 1 gram per watt per flowering cycle indoors. As long as you use the lamp and reflector as designed I think they all work. Since you are asking about PAR values I got to thinking about it. The physicists and grow light salespeople may have to bear with me here or chime in, this forum I'm sure has some of the most optimized grows just look around. Compared to a micro-grow in a tent, hanging a light from the rafters in a greenhouse looks like it would provide a small fraction of the usable light to plants. Light intensity falls off with distance squared. Looks more like regular garage bay lights or electric ceiling heaters. I am exaggerating here but the all on one open style looks like it gets super hot completely ignoring heat management or equipment longevity but it's ok because it covers a 5x5 canopy.

I am considering solutions for micro level room.



I was bit astounded that numeric info was nowhere available.


Yes.. each reflector has it merits but without exact info it more or less guesswork.

I have managed to gather some guidelines on how the light output is distributed (in 3D) but no numerical data..


From vertical growing section .. standard horizontal bulb .. only ~25% of lamp output hits plants directly, rest is through reflectors. author gave pretty bad estimates on efficiency of reflectors.


I did consider vertical scrogging .. tempting but I think it is a delicate style of growing and might be too demanding for me.


Then I started looking more into different reflectors .. and could not find any good data .. So I opened up this thread to see if anyone has seen any.. (apparently no)..


The more I have thought about it the more it starts to feel that a cooltubed horizontal bulb relatively close to standard reflective tent would give close to same values as same setup with extra reflector. (measured at estimated canopy in late bloom state)


Aluminium (or white paint) used in reflectors is not really good at reflecting.. many reflective fabrics used in tents have much higher reflective % (which to me translates to better IF heat is managed to prevent fire)

I'm also interested in this. If it doesn't help a bunch I'll be more than happy to remove it just to low my temperatures 1 or 2 C
Keep us up to date if you find anything

You are giving a lot of information here. The improvements in reflector design I'm sure were spurred by this burgeoning industry assuming the higher price of cannabis however the principles are the exact same for any food or plant cultivation. The large square or rectangular reflectors will even out the light for a grow tent in horizontal configuration for scrog or sog, whatever. But as you said distance to the bulb is what you want to measure and a cool tube has a 180 degree reflector in it right next to the bulb and they are less expensive to boot. Then in vertical configuration you can probably squeeze a lot of vegetation around a bulb but the logistics of how to micromanage and flower that gets more complicated IMO so I agree I am not sure if it would be worth it. 1 or 2 vertical bulbs in the middle of a tent will illuminate the whole thing, but the outsides will still not receive light just like the lower branches in a vertical setup. You could put 4 315s in cooltubes in the corners of a tent and one in the middle which might be quite energy efficient but would cost about five times as much as a single 1000 hps.

the price of par meter is ~150 usd .. bit too steep to dish out to satisfy my curiosity.

bit of repeating same stuff from my previous post.. better output ( I hope )

As for reflection .. polished aluminum is ~90% (best - less for wear) for our desired part of spectrum.

Mylar ~95% and ocra slightly better at 96-98% (?) (best - less for wear also) different sources give bit different numbers..

Naturally aluminum has the advantage of being extremely fire resistant so great solution for bare bulb.




But..

If tube and lamp can be placed .. for example.. close to reflecting ceiling of tent .. I would venture out that the results would not be too shabby.

Iamnumber said:

the price of par meter is ~150 usd .. bit too steep to dish out to satisfy my curiosity.

bit of repeating same stuff from my previous post.. better output ( I hope )

As for reflection .. polished aluminum is ~90% (best - less for wear) for our desired part of spectrum.

Mylar ~95% and ocra slightly better at 96-98% (?) (best - less for wear also) different sources give bit different numbers..

Naturally aluminum has the advantage of being extremely fire resistant so great solution for bare bulb.




But..

If tube and lamp can be placed .. for example.. close to reflecting ceiling of tent .. I would venture out that the results would not be too shabby.

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... the best investment you will ever make IMHO. It allows you to dial in your plants and lights for maximum efficiency. PAR values are great guidelines but are general in nature (one size fits all) your meter will tell you were your set up needs adjustment. e.g dialing it in for your grow.

Wouldn't mess with a par meter myself. Get as close as the footprint and temp will allow. There are s many lights out there and such a fast growing tech industry with knew lights yearly. Almost monthly with led.

Yet there is still not a perfect light. Either it's effecient and doesn't penitrate, no uv, loose buds, or whatever. No light has it all yet.

Take it from an old head bro.....before PAR, UMOLS , ppfd`s , and DLI`s , we were taught that 35-50 watts per sq ft were conducive to optimum plant health and yield-ability as long as environment was dialed first and foremost.....me ?....

I grew inside with nothing but vertical bare bulbs hangin for well over 20 yrs with never less than 1.2 gpw yields , but I also employed laboratory conditions with environment dialed to the tits....now.....

If you use a tent or any small space , the best usage of light is with a bare bulb hanging in a parabolic reflector.....They`re marketed as "Vertizontal Reflectors" and allow 360 degrees of light to be blasted down as well as at the reflective walls to help with sideways dispersion to mids and lowers of the plants during the lights on cycle…...also....

Exchange your room`s air twice per minute to remove as much heatgain as possible without using ac to supplement, but with 50 watts per sq ft , you will need additional cooling in close quarters.....I built all my rooms and lined em with reflectix/reflective covered bubble insulation.....Never use mylar…..crinkles up , causes hotspots ,and a bitch to wipe down and keep clean.....

Reflectix bounces light up , down , and all around as it disperses and diffuses everything that hits it WHILE having an R factor that helps insulate the room....but....Orca film will be the most reflective per all the tests.....there`s also Prodex reflective insulation covering that`s stronger and costs more than reflectix , but if you`re not in the states then I`m not sure what all the same items are called elsewhere.....anyways.....

A dimmable 1KW with a parabolic is best case scenario in my book , but the 315 cmh`s are awesome too but costly.....a tent with as much height is needed with HID lighting.....If you have the funds , LED`s for small areas are the best of the best for environmental control as well as watts per sq ft......and lastly....

Environment first or it matters not how much light you shove up their ass , but if you use 35-50 watts per sq ft as a guideline you`ll be golden once you dial environment , so....Good luck and...…

Peace....DHF....

DunHav' nFun makes a great point about establishing the fundamental environmental conditions before all else. Start around 35-50w per sq ft of CMH/CDM/HPS/Halide (LED may be different) and commit to a manageable layout or grow style like scrog/sog/or whatever. Nail down Proper temp (air and root zone), humidity, air exchange and circulation, light tight and so on based on that space and light set up.

Just commit to a environmentally dialed in space and grow style, and light that. I will say that making the whole space, including the floor, as reflective as possible is a great starting measure. I prefer the Orca film.

Thank you for feedback.


I am now sitting at my drawing board and will be for a while still.. (hiatus forced upon me).


Yes, the basics are 85% of "the whole" .. and getting the last few % is ever more difficult.


I think I will have multiple setups.

One with 600w hps + cooltube, vertical with [FONT=Arial, Helvetica, sans-serif]parabolic reflector (or similar). I think I will try to go down cooltube route as it allows me to lower my (heat)ventilation.[/FONT]


One with 400w hps + cooltube, horisontal. Lower space so I will try to keep distance between cooltube and tops as small as I can WHILE enough so that reflector can spread the light to large enough area.


What would be "large enough area" ? HPS gives less light at top and at bottom of bulb so instead of square area (as most grow tents) I think I will go for 2'4" by 4' or something similar.
........_______....... 0 deg

...../................\.....20 deg (?) section

../...........o..........\... 45 deg section


Sides at much lower angle (and longer) perhaps 45 deg at very end of wing and 20deg or so in mid section on each 'wing* while center is at 0 deg reflecting light down. Hmm.. as I write this down.. maby a slight negative angle to reflect more light to sides .. so from centermark outward.. maybe -3 deg section (6 inch 15 cm) 0 deg section also (6 inch 15 cm) 20 deg section (6 inch 15 cm) and final 45 deg section (6 inch 15 cm). this would mean each wing would be 2 ft 60cm for total of 4ft 120cm.



400w for 2.5 ft by 4 feet area would give 40w for ft2 > ok, maybe some support lights.



Naturally the reflector would be more en-longed rectangular than 'standard' square. I will try to keep the reflector as 'low' as I can.. perhaps a small ( around or bit over half of an inch ?? ) airgap between top reflector and cooltube.



PS. working things out as I write this so.. work in progress..

DunHav`nFun said:

Environment first or it matters not how much light you shove up their ass , but if you use 35-50 watts per sq ft as a guideline you`ll be golden once you dial environment , so....Good luck and...…

Peace....DHF....

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Thanks for great advice!!


As follow up.. Assuming environment is near optimal co2 levels, vdp etc.. what kind of watts per sq ft can plats use (before law of diminishing returns kicks in)?


someone adviced 65 watts and my guess was 65-75w per sq ft. ? advice needed with pretty plese ..

Pretty please huh......LOL.....Aight....first thing you need is the VPD/vapor pressure deficit chart that will give you the RH % you need to keep the room at with the ambient dialed temps you achieve.....Elevated light equals elevated heatgain to deal with so again environment first before blastin their ass with light.....now.....

Rule of thumb for watts per sq ft on flat grows has always been a 1KW light covers a 4 x 4' area and that`s 62.5 watts per sq ft , but reflected light that greatly diminishes it`s strength and penetration ability , especially through glass sealed units , and that`s where I learned with vertical bare bulbs that 50 watts per sq ft is the sweet spot for optimal growth and yield IME …..

Supposedly the new DE fixtures like Gavita`s will cover 5 x 5 ' areas but they`re like high bay lighting mounted to the ceilings to prevent hot spots and heat stress/light bleaching to the plants so again controlling environment is most important since those unit`s aren't air cooled with even more heatgain to deal with in the grow area......and lastly.....

Sure you can use up to 75 and even 100 watts per sq ft if you can control environment but more importantly plant metabolism needs cuz as light increases so does heat and CO2 needs and it`s all relative if you have the funds , intermediate grower skills and have the tools and equipment to deal with such issues in the search for the most yield and highest quality...….but.....

Get dimmable ballasts and start slow......Dialage comes from runs under your belt......no way around it.....proper watts per sq ft are but a small part of the equation.....important ….but the sum of the whole takes time ….anyways.....

Good luck and....

Peace......DHF.....

DunHav`nFun said:

Pretty please huh......LOL.....Aight....first thing you need is the VPD/vapor pressure deficit chart that will give you the RH % you need to keep the room at with the ambient dialed temps you achieve.....Elevated light equals elevated heatgain to deal with so again environment first before blastin their ass with light.....now.....

Good luck and....

Peace......DHF.....

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Yes, put a smile on someones face! allways a good start for a day.


yes. vpd chart is the key map for temp/humidity.

DunHav`nFun said:

Sure you can use up to 75 and even 100 watts per sq ft if you can control environment but more importantly plant metabolism needs cuz as light increases so does heat and CO2 needs and it`s all relative if you have the funds , intermediate grower skills and have the tools and equipment to deal with such issues in the search for the most yield and highest quality...….but.....

Get dimmable ballasts and start slow......Dialage comes from runs under your belt......no way around it.....proper watts per sq ft are but a small part of the equation.....important ….but the sum of the whole takes time ….anyways.....

Good luck and....

Peace......DHF.....

Click to expand...

Thank you for the advice!! I just did some basic number crunching and .. found out a weak spot in my plan .. So I will have to figure out minor adjustments to key light placements ..



Plan was to use parabolic reflector with vertical bulb. wattage would be ok for standard grow but not enough when running with co2. Plan was also to add led lights as needed BUT parabolic reflector is bit tricky when it comes to adding more lights (as it is big - it block potential support light placements)



Two clear paths .. A) smaller parabolic reflector. start with 400w hps (standard setup) and swich to 600w when high co2.B) start with larger parabolic reflector and 600w hps and B1) upgrade to 1000w hps - I am not too keen as other light techniques are offering good alternatives (led, cob led, cmh) B2) add support lights - bit tricky placement with this reflector.


I am leaning towards having (same w for same area) multiple lights as I do believe that to be 'better' in many ways (more even light distribution would be biggest advantage). downsides would be bit more expensive and bit more complex setup.


parabolic reflectors (afaik) work 'better' when they cover larger area. more work to set up two smaller to cover same area. easier to get reflective angles right.


well.. now I know I have a spot that requires my attention.. and time to give it attention it deserves (and then some more ..)