Hps heat output from dimmable ballast

[joker_the_smoker]

I agree with karsa on that buddy. I wudnt prefer to dim 600 to 250 for that reason. I dont.mind flickin it down one usually but u need more than a sponge to help the rh matey. Get a humidifer asap bro. An a cool tube will also help you run a bigger light. But with weather getin colder temps shudnt be issue if you got intake an outtake sorted.

[Badgerbadgerbadger]

I think that the spectrum would not change, the same as when you have a torch with different brightness settings, the colour of the light doesn't change, just the intensity.
Manufacturers are producing these dimmable ballasts and bulbs, and tons of people are using them and pulling off successful grows. I would have thought that there would be a lot of complaints if they weren't working. The tech has been around for several years now.
The thing I can say from this is that I know for a fact that when I run my 600w bulb at 250w it runs cooler and less bright than when I run my 250w bulb at 250w. What the implications of that are, I don't know, but I'm going to stick with the 600w and see how it goes.

[Badgerbadgerbadger]

I'm running the tent with nothing in it at the moment, so RH will go up once some plants go in there, a wet sponge just a temporary fix to get it up a bit for now..

[Karsa]

222635188694 this one is pretty damn decent. Top up once a day. If you want to top up less then you'll need a 8litre + also if you can deionize your water even better or buy it from Tesco or the like. Will stop the calcification.

[Karsa]

In the mean time get an oscillating fan to blow over a bowl of water

[Bud Lightyear]

I think that the spectrum would not change, the same as when you have a torch with different brightness settings, the colour of the light doesn't change, just the intensity.
Manufacturers are producing these dimmable ballasts and bulbs, and tons of people are using them and pulling off successful grows. I would have thought that there would be a lot of complaints if they weren't working. The tech has been around for several years now.
The thing I can say from this is that I know for a fact that when I run my 600w bulb at 250w it runs cooler and less bright than when I run my 250w bulb at 250w. What the implications of that are, I don't know, but I'm going to stick with the 600w and see how it goes.

The spectrum does change, if you underpower the rated wattage it goes to the red spectrum if you overpower it goes towards the blue end. Its well documented on the Lumatek web site....See below.


Obviously the amount of PAR light available has an effect on the growth of plants. PAR is the part (frequency) of light that plants use to grow. Lamp manufacturers design their lamps to produce a certain amount of PAR over the power range of the lamp. For a 600w lamp a range of 585w to 660w of lamp power produces normal PAR as designed. As the lamp power goes above or below that range then the frequency of light it produces changes: more to the blue spectrum when overpowering and more to the red when underpowering. This has an effect on the growth rate and development of plants. If you stay within the range (585w to 660w ) there is not much difference, but obviously overpowering your light does cost more energy. Though you strive to have the optimal light every time there are circumstances when you deliberately may want to dim your light, such as too high temperatures. The light colour changes more to red, but that effect is less dramatic for the plants than the high temperature is.

Regards BL

[Badgerbadgerbadger]

OK, interesting. So that would explain why my 600w bulb looks dimmer than the 250w bulb. I'll see how the plants respond to it when they pop up, and maybe try a week of each bulb to see if there's any noticeable difference.