Is it me or do HPS lights 'seem' dimmer than MH?

I have a 1000W HPS light I just put on today and compared to the MH light (conversion) it seems dimmer, which is weird. Maybe my eyes are playing tricks on me or the blue just seems more intense when it really isn't. Can't imagine anything is wrong, brand new light and all. Although, not exactly a state of the art hortilux or fancy pants brand. (Growbright, from HTG supply.) Still, brand new and 1000W is a 1000W.

Thanks for any input for my poor attempt at a thread here. And I have thought about getting a light meter, but eh seems like a waste of money. . . until now!

HPS has a way higher lumen output than MH, do you have a ballast thats good for both?

The light your eyes see is different from the light your plants see. And yes MH do look brighter than HPS.

maybe its the spectrum of light they look diff to eye
hps is a soft jellow mh is a hard white

i like cmh ceramic metal halide runs hps ballast has a hard whit blue clear

i work wit 2 x 250's a hortilux -hps and a phillips-cmh i think thy are sum of the best bulbs

1Luv

MH bulbs run hotter than HPS. I have a 1000W. HPS and a 1000W. MH set-ups and have used both for years.
Maybe the MH seems brighter because it is a hotter bulb.

BigSteve.

I think watt for watt MH bulbs do look brighter, but its because they put out more of a blue-white light compared to HPS's amber light.

But how they look to your eyes isn't really what important, unless you're actually using them to light your driveway or the like.

If you're using them to grow plants, what matters is how the lights look to the plants' chloroplasts, or more specifically what spectrum of light the plants put out. The type of light plants need to grow isn't the same as the kind you ideally use to see.

they are brighter dont believe me use a light meter, i have a sunmaster mh600 watter that puts out more lumens then my 1k philips hps

Jogro said:

I think watt for watt MH bulbs do look brighter, but its because they put out more of a blue-white light compared to HPS's amber light.

But how they look to your eyes isn't really what important, unless you're actually using them to light your driveway or the like.

If you're using them to grow plants, what matters is how the lights look to the plants' chloroplasts, or more specifically what spectrum of light the plants put out. The type of light plants need to grow isn't the same as the kind you ideally use to see.

Click to expand...

Thanks to all the replies. I think this sums it up. The amber color just seems dimmer and less intense to the eye as I suspected. I've been doing some research in light of my question here and have caught onto the scientific trail:


The "blue" cones are identified by the peak of their light response curve at about 445 nm. They are unique among the cones in that they constitute only about 2% of the total number and are found outside the fovea centralis where the green and red cones are concentrated. Although they are much more light sensitive than the green and red cones, it is not enough to overcome their disadvantage in numbers. However, the blue sensitivity of our final visual perception is comparable to that of red and green, suggesting that there is a somewhat selective "blue amplifier" somewhere in the visual processing in the brain.
The visual perception of intensely blue objects is less distinct than the perception of objects of red and green. This reduced acuity is attributed to two effects. First, the blue cones are outside the fovea, where the close-packed cones give the greatest resolution. All of our most distinct vision comes from focusing the light on the fovea. Second, the refractive index for blue light is enough different from red and green that when they are in focus, the blue is slightly out of focus (chromatic aberration). For an "off the wall" example of this defocusing effect on blue light, tryviewing a hologram with a mercury vapor lamp. You will get three images with the dominant green, orange and blue lines of mercury, but the blue image looks less focused than the other two.

( http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html#c3b

And boy my neighbors would be pissed if I had 1000W driveway lights blaring at night.

I might still get that light meter for the hell of it. It's probably a good tool to have either way.

Here' a link for anyone interested in this stuff:


http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/Sample-Chapter.pdf

There's a section on 'brightness' but I had trouble pasting it. It basically said our eyes are more sensitive to blue when it's darker I believe, so I figured that translates from going from a dark/low light room to a 1000W 6500k MH light being much brighter or 'amplified' than HPS. (Or more shocking to the eyes.)