Help me choose a light

[Call_Me_Bob]

Originally Posted by Magnus A

I have never considered the "normal" T5, therefore I did not recognize the statement that T5 and T8 had the same efficiency above.

I can by 54w T5HO fullspectrum 6500K in Sweden for about 7 dollar each. I consider that neglectible compared to other costs associated with our hobby...

im so jealous of you!! haha! a 4 foot 1 bulb T5HO fixture with reflectors costs $30+ here!

[QUOTE=naoki;522830]

Originally Posted by Call_Me_Bob

true, t8's and t5's are not that different in terms of efficiency and output, but t5s take up less space, therefore they are more efficient in terms of Output to Space Taken
[\QUOTE]

That's right. You should note that the temperature influence the efficiency differently, though. You are also right about the space-efficiency. As you mentioned, 2 bulbs of T8 has similar output as 1 bulb of T5HO. If you need to put lots of lights for high light orchids, then T5HO is better.

The other advantage of T5/T5HO is that the reflector can be more efficient.

yes, as mentioned the reflectors are more efficient in most T5s. although there are varying degrees of reflector quality.

[naoki]

Originally Posted by Magnus A

Not really, I have the same configuration but the tubes are mounted with individual reflectors very closed to maximize the light. My 4 T5 with reflextors span 20 cm (8'') across.
My light setup:

You see the individual T5 tubes under the reflectors on both sides. The gray metal case is 17.5 cm or 7''.

Yes, it can be designed to have more T5HO bulbs per width of the fixture. But the one which Bob got is Hygrofarm 4 bulb unit (I use this), and the point of Bill is that the size isn't different from 2 shoplights.

Bob, Mangus is talking about the light bulb (not fixture)

In the US, T5HO bulb is 3.2 times more expensive than T8 ($8 vs $2.5), and T5HO bulbs are less common. So it is not a big difference but when I was young (I think Bob is 16, right?), something which you may consider small made a big difference. Being said this, the cost of electricity is much more significant (it costs me $300 per year for a small scale T5HO + LED grow tent).

[Call_Me_Bob]

Originally Posted by naoki

Yes, it can be designed to have more T5HO bulbs per width of the fixture. But the one which Bob got is Hygrofarm 4 bulb unit (I use this), and the point of Bill is that the size isn't different from 2 shoplights.

Bob, Mangus is talking about the light bulb (not fixture)

In the US, T5HO bulb is 3.2 times more expensive than T8 ($8 vs $2.5), and T5HO bulbs are less common. So it is not a big difference but when I was young (I think Bob is 16, right?), something which you may consider small made a big difference. Being said this, the cost of electricity is much more significant (it costs me $300 per year for a small scale T5HO + LED grow tent).

Ooohhh haha! thoght she meant $7 fixtures! haaha!

yeah im 16, haha so i dont pay for the electricity it takes to run them, lol. yeah the bulbs will cost more, but for me its worth it, and i dont have to change them that often, so im not too worried about that.

[Magnus A]

Ah, Yes, the cost I mentioned was per light tube and not for the holesetup! Those are much more expensive!

For orchid growing you often want alot of light, more than the ordinary plant grower that need extra light.
If you need really alot af light and cant go for MH or similar lights for green houses you not look at plant growth equipment but rather look into the salt water aquarium world. They need much more light per area in general than we orchid growers do and the light fixtures for aquarium cram in as much light it is possibly.
Though you should not use their light tubes as they are way to blue. But the fixtures really good and often water protected. My fixture I show above is made for an aquarium.

/M

[Call_Me_Bob]

Funny you should mention that, haha. One of my other hobbies is actually planted aquariums. Not salt water and reefs, but I familiar with the lighting they lighting they use is often very expensive.

[Magnus A]

Yes they are often expencive but you can find good stuff on sales! And you do not need to buy their expensive light sources, you even do not need to buy expencive plant growing light sources. Go for something that is full spectrum and a color temperature on around 5500-6500 K and your plant will thank you! Maybe not in an optimum way, but in a good way compared to the money spent.
IF yougo for the perfect light you will spend more money than it is worth! Go for "good enough" light and spend the rest on nice plants.

[johnblagg]

Hey Bob I have great success with my home made fluorescents using off the shelf GE multi volt pro electronic ballasts ... PN # GE296HO-MV-N-DIY and Lothonia Lighting 65 watt triple tube flat compact fluorescent T4 bulbs made to use in outdoor flood lights. Since the ballast will power bulbs from 48 watts to 96 watts they give you the option of just buying higher wattage bulbs if you ever need to increase light output and the ballast is high output also ...
They put out 4,300 lumens at 6500k and each ballast will run two of them giving you 130 watts in a small footprint flat cfl bulb 4 inches wide x 8 inches long and just 1 inch thick so they take up almost no space .

Ballast runs $37 bulbs are $13 each so for about $70 you have a great set of lights I use regular lamp cord wire in 2 pairs from the ballast to each bulb and it is flexible and easy to work with so you can place the ballast several feet from the bulbs and it gives you great flexibility when your hanging attaching/mounting the lights .

I keep these about 2 feet above my plants and have more than enough light using one bulb to cover a 2x2 foot area with enough light to bloom anything I grow and for lower light plants raise them a bit higher ... at ( inches above the tips of the leaves they will redden a catts leaves a bit more than I like and I usualy try to keep them 12 inches above plants in general.

used these all last winter with great results testing them and this year added 2 more sets of them Im running 4 sets and covering a area 16 feet x 2 feet wide with enough ambient light reflected from walls and ceiling to grow ornamental peppers sitting in pots on the floor and 3 feet away from direct light from them.


Cheap effiecient and readily available at home depo or lowes ... replacing bulbs once yearly is not a issue and $13 a bulb either.

[31drew31]

Nice work with your lights JB, but without a reflector you are wasting 50% + of your light by letting it shine away from your plants. Just something to think about.

[Call_Me_Bob]

here is what i ended up doing. i took my metal shelf and reconfigured it so its wider and i can utilize all 5 tiers. there are three tiers about 4' tall, and then two tiers under them. the undersides just have some of the old t12s i used underneath. i havent gotten my light yet, but i have two dome lights with 6500k CFLs for now, and the windows. i used to grow phals in the middle of this room, alot farther from the windows, and they did fine. so im not too stressed about getting a light, but as i can afford it, id like one. i still need to get something to catch water though...


Untitled by orchidman10, on Flickr


Untitled by orchidman10, on Flickr

[johnblagg]

Originally Posted by 31drew31

Nice work with your lights JB, but without a reflector you are wasting 50% + of your light by letting it shine away from your plants. Just something to think about.

look at where they are hanging ... see that white shelf above them painted flat white ... I do believe that is a basic reflector .. then look at the wall behind em ...yep another reflector ... lol but it is kind of hard to see the wall and the shelf with all that light