FROSTED 400W MH??? Can I grow anything with this?!?!?

newbienewb

Member
Seen this today and picked it up for CHEAP!

It is not clear glass like normal MH, but frosted from tip to almost base. Can I grow with this?

My local Hydro store guy didnt know, thought I'd put it out there.
and yes I know I know, put it in and test and see. but if anyone knows...

Thanx
 

strain stalker

New Member
...yes, you can grow with that bulb. I believe they call the white cloudy glass, a phosphorus coated bulb. They produce a different spectrum at the cost of a few lumens.
 

strain stalker

New Member
METAL HALIDE - (MH)

Metal halide bulbs are very efficient and produce between 65 and 115 lumens of light output per watt of electricity used. MH bulbs produce a light that is very close to full summer sun, with a spectrum rich in the blue end. This promotes fast vegetative growth and compact, stocky plants with short internodal leaf spacing.

Metal Halide bulbs create light by passing electricity through an clear inner arc tube that is enclosed in the vacuum of an outer clear glass tube. This inner arc tube contains mercury and other metals in iodide form. When electricity is applied to these metal iodides they give off very intense light and heat. The outer casing can be either clear or phosphorus coated. Most gardeners prefer the clear bulb as it produces the brightest white light available.
 

RecklessLemming

Active Member
WooHoo!! My first post.

I have only recently become interested in the cultivation side, but as someone who has worked for the last 15 years in commercial and industrial lighting I feel qualified to provide you with some information on the subject.

As stated previously what you have is a coated metal halide.

Metal Halides and High Pressure Sodium lamps are used primarily for general area lighting applications and as such 99.9% of the time they are in fixtures with reflectors or lenses that direct the light to the areas of need.

In the .01% they are used without a lens or reflector and the phosphorous coating acts to disperse the light evenly in all directions.

In general, with regard to the three major manufacturers of lighting (Osram/Sylvania, General Electric and Philips), there is no significant loss of light output (lumens).

In fact, the CRI (Color Rendering Index) of the coated lamps can be higher, meaning their output in the yellow, orange and red wavelengths is higher.

Is the increase in the 570 to 650 nanometer range better for your purposes? I can't speak intelligently on that subject, but maybe someone else will help with that aspect of your question.
 

strain stalker

New Member
...good info there RecklessL, people are misinformed on these MH. However, I was under the impression that you lost some, very little, but some lumens. Just as you stated, I wanted to get the even spread throughout the garden without a reflector, and the added bounus of the specturm difference almost had me, however....the lumen loss made me go with the typical MH (clear blulb). Now I'm pissed :) ...time to medicate!

...so, your bulb can grow bud! ...now how old is it? ...you lose lumens over time!
 

newbienewb

Member
Wow, thanx REckless Lemming

Now I can veg with that bulb and use my dual band for flower.

This place ROCKS!
 

RecklessLemming

Active Member
I was under the impression that you lost some, very little, but some lumens. Just as you stated, I wanted to get the even spread throughout the garden without a reflector, and the added bounus of the specturm difference almost had me, however....the lumen loss made me go with the typical MH (clear blulb). Now I'm pissed :) ...time to medicate!

That is correct, there is nominal lumen loss of approximately 1000 lumens or 4.3% (23,500 versus 22,500) IF you are burning these types of lamps in a vertical orientation (base up).


However, if you are burning these lamps in a horizontal orientation then there is no difference (20,500 versus 20,500).


Yes, you read that correctly, HID lamps are sensitive to vertical or horizontal orientation and a horizontal burn position will cost you more lumens than coated versus clear.


This has to do with the mercury in the lamp as it prefers to condense in the point furthest from the arc tube (the hottest part of the lamp) and can do so more readily in base up position.


In a horizontal burn position the mercury tries to condense too close to the arc tube and can't, resulting in less than optimal lumen output.


The same concept applies to compact fluorescents.


Just for a change of pace though linear fluorescents prefer to be operated in a horizontal position.
 

RecklessLemming

Active Member
Some other information about HID and fluorescent lighting that might help you.

Average Rated Life: They determine the average rated life by sticking 100 lamps in a room under ideal conditions, meaning controlled ambient room temperature, not being jostled, etc. When half of the lamps burn out they call that the average rated life. Because you won't be operating your lamps under these type of ideal clinical conditions you should expect the majority of your lamps to burn out before they reach the average rated life.

Initial Burn-In Time: HID lamps contain a variety of gases. The first time you fire up an HID lamp (Metal Halide or High Pressure Sodium) you should burn them for a minimum of 18 hours straight to allow the gases to mix properly.

Lumen Maintenance: Using a 400 watt metal halide as an example, a brand new lamp burning in a vertical position (base up) will have an initial output of approximately 36,000 lumens or 32,000 lumens if operated in a horizontal burn position. By the end of the lamp's average rated life the lumen output will have dropped to approximately 45-60% of the initial lumen output. If you wait for your lamp to burn out before changing it your plants will be receiving significantly less lumens than they would from a new lamp.

CRI (Color Rendering Index): The higher the CRI rating of a particular lamp the closer it is to simulating the spectral characteristics of natural light (the sun). The particular spectral deficiencies of any particular lamp are dependent on what kind of light it is intended to put out. For example, metal halides are heavy in blues, greens and yellows and short on oranges and reds. High Pressure Sodiums are heavy in reds, oranges and yellows and short on blues and greens.The spectral deficiencies in fluorescents vary depending on whether they are warm whites, cool whites or daylights.

I hope this helps
 

terrorizer805

Well-Known Member
...yes, you can grow with that bulb. I believe they call the white cloudy glass, a phosphorus coated bulb. They produce a different spectrum at the cost of a few lumens.
true you can grow with it, hey SS you got that qoute from the ready-set-grow vid on youtube?
 

strain stalker

New Member
true you can grow with it, hey SS you got that qoute from the ready-set-grow vid on youtube?

...ummmm, well...I have that video, LOL, really can't recall if that is where I got that info. I have seen my, "Ready Set Grow" dvd a million times though...LOL, so...maybe! I actually downloaded it off of Ares. (free fileshare'n download)

...I also view alot of Jorge Cerventas' dvds, which are also on Youtube btw. Very informative.
 
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