I recently switched from a 250 HPS to a 400 MH, and it seems the HPS was significantly brighter looking than my current 400 MH.

Is that normal? Or do you think I have an issue somewhere?

Both ballasts were disassembled and reassembled by me, so I know the wiring is correct. It's all new wiring in the 400.

The only other change I made was a new hood that I built. I had to seeing as how the 400 wont fit into a bake a round tube. :( So I built a new aircooled hood that seems to be working pretty well.

TIA

[BOZWELL]

hps puts out more lumens pre watt than mh so it is slighlty brighter
but not 150 watts brighter could be somthing to do with the way our eyes seem differant lights
or I could just be far to stoned and babbling sh!t

high bud,
you [i]did[/] change the ballast to accomodate the new lamp, correct?
just saw no mention of this in the short description you gave.
Exactly how this relates to the issue at hand, well, it doesn't but just lookin out as u did not specify the exact type of ballasts used.

A 250 Watt High Pressure sodium lamp REQUIRES a grounded 250 Watt HIGH PRESSURE SODIUM-specific ballast.
A 400 Watt Metal Halide lamp REQUIRES a grounded 400 Watt METAL HALIDE-specific ballast.

***Using the incorrect ballast/wattage you have an even greater fire hazard than you started out with by running DIY HID's inside.. the bulb and ballast MUST correspond exactly***

The two bulbs are like night and day in the respect of how your eyes perceive the light (keep in mind this has ABSOLUTELY NOTHING to do with the plants)

HPS light "throws itself" rather well when compared to white lights, for whatever reason. This may be what's throwing you off.

got a pic of the new hood? if its air cooled make sure its on the side so if light does escape it's minimal, remember when an hps is mounted horizontally the light goes up and down.. a different pattern than your mh. A light leak in the top is best avoided if possible...

Hope this helped you
if this is all known to you already,
well, maybe it helps the next guy.

Have a great weekind and good gr0win

cj

[Dr. D]

Are u using this MH for flower or veg i dont like mh i think they put off too much heat and not as much light as a hops...my 250hps can take either hps or mh some ballasts can and some cant..

Brand new bulbs can take a while to reach full brightness.

[Babbabud]

I have a 1k of each hps and mh hangin side by side . As the hps looks a bit orange the mh always seems brighter to the eye. The mh does not put out as many lumens is my understanding but does look brighter to the eye because of its bright white light.

[I.M. Boggled]

to an onsite primer / tutorial on H.I.D.'s.

I Hope it's of some help to others new to indoor growing in understanding the complexities of H.I.D. Systems (and the electrocution dangers thereof...)

Safety first!.

I recommend always using a Ground Fault Circuit Interrupter (GFCI) whenever working in the vicinity of water when using (high Voltage/ amperage) electrical equipment.

High Intensity Discharge lamps) Principles of Operation, Circuits, Troubleshooting
https://www.icmag.com/ic/showthread.p...ghlight=kelvin

IMB - I love that cartoon!

Walmart carries power strips that have GFCI protection on them - the brand is Fire Shield


I use these on everything in my garden as an added measure of safety.

Home Depot sells the smaller ones, but Walmart has both sizes and the prices are a lot cheaper than HD.

Originally Posted by CaptainJack

high bud,
you [i]did[/] change the ballast to accomodate the new lamp, correct?
just saw no mention of this in the short description you gave.
Exactly how this relates to the issue at hand, well, it doesn't but just lookin out as u did not specify the exact type of ballasts used.

A 250 Watt High Pressure sodium lamp REQUIRES a grounded 250 Watt HIGH PRESSURE SODIUM-specific ballast.
A 400 Watt Metal Halide lamp REQUIRES a grounded 400 Watt METAL HALIDE-specific ballast.

***Using the incorrect ballast/wattage you have an even greater fire hazard than you started out with by running DIY HID's inside.. the bulb and ballast MUST correspond exactly***

The two bulbs are like night and day in the respect of how your eyes perceive the light (keep in mind this has ABSOLUTELY NOTHING to do with the plants)

HPS light "throws itself" rather well when compared to white lights, for whatever reason. This may be what's throwing you off.

got a pic of the new hood? if its air cooled make sure its on the side so if light does escape it's minimal, remember when an hps is mounted horizontally the light goes up and down.. a different pattern than your mh. A light leak in the top is best avoided if possible...

Hope this helped you
if this is all known to you already,
well, maybe it helps the next guy.

Have a great weekind and good gr0win

cj

Hehe. Yes, I did change out the ballasts. After doing a bit of research around the net, it appears that due to the different wavelengths being produced by the different types of systems, the an HPS bulb will appear brighter than a MH.

from what I have read, MH and HPS give of diffrent light spectrums for diffrent stages of growth (veg and flowering). But have heard running a HPS and a MH during flowering is benidicial. It's not so much as lumens (you should adapt your space to your equipment specs, not size of room) I'll get some post from some reputable vendors and post later...when I find them. just my ,02 cents

HTH

Hope this wasn't topic off topic.