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High Pressure Mercury Lamps

Smeerworst

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Wow, those are some awesome colors!

Havn't seen anything like these before, thanks for sharing!
 



Cyparagon

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Be wary of those values though. A "20,000k" lamp will vary greatly in color from manufacturer to manufacturer, and even a little bit from lamp to lamp. I bought a "10,000k" lamp once that ended up having an identical spectrum to a regular mercury lamp for some reason (which are around 6800k). No red; terrible CRI.

I had a 300W spotlight version when I was a kid that was surplus from industrial leak detection. It always looked red in output for me and I first thought it was an IR lamp instead of a UVA lamp! It wasn't until I realized it was causing fluorescence that I figured it out.
Eh, actually, you were right the first time.

The spectrum of an incandescent will always roughly follow a blackbody curve. So unless you can get the tungsten to 8000k (you can't), it will always have high IR output, medium visible output, and low UV output. Woods glass only filters visible, and IR is still passed. So you're still left with high IR output and low UV output. Here is a typical 75W tungsten black light:




As you can see, it is abysmally inefficient at producing UV. You can see a hill in the violet if you look carefully.
 

Things

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I had a 60W incan blacklight bulb at one point, even a teeny tiny 5W flouro blacklight tube kicked it's ass in UV output. Dunno who's idea incan UV bulbs were :D
 

Sigurthr

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Dunno who's idea incan UV bulbs were :D
It was driven by profit hunting. Take a $0.30 bulb and apply $0.01 worth of coating to it and charge $9.99 for it.

I remember using one of those 75W "black light"s as a heat lamp for something when I was young, worked great since the coating turned all the blocked visible into longwave IR.
 

DashApple

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Those are neat too. They're only 20lm/W or so, but they supposedly last for 10,000 hours which isn't bad considering it's a tungsten filament. The tungsten warms the light up and increases CRI to ~45. Warmup of the one I have:

Nice , I did try and find a 1.25 Kw one , but found and purchased a 1Kw version .

The BL bulbs are nice aswell I got both 400W bulbs for £10 and ballast for £15 , they do kick out some UV light xD .
 

DashApple

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Not to jack the thread , but my 1 Kw self ballasted mercury lamp arrived xD

Cost £50 w/PP .

First photo shows the tungsten filament and arc tube under it . quality isn't to good as the photo was taken though a welding mask filter .


IMG_0482[1] by TwirlyWhirly555, on Flickr

The lamp itself .


IMG_0488[1] by TwirlyWhirly555, on Flickr
 

Sigurthr

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Very nice!!

Just for those who don't know; Metal Halide is a subset of High Pressure Mercury. All MH bulbs are HP Hg with additional salts in the arc tube.

On that note I got the 4200K 100Watt MH bulb today and the seller described it wrong in the listing. It isn't cost effective to send it back so I'm stuck with it. This is a pulse start bulb and the listing showed a probe start (has 3rd electrode to ignite the mercury arc from low voltage). Pulse start ballasts have a 4kV pulse to ignite the lamp but I only have probe start ballasts.

It seems it is hard to find probe start MH bulbs under 400W. I've had no luck coupling HV DC into to line AC to ignite the bulb (it is much easier to couple AC on to DC than vise versa). Not wasting to fire up my TC just to ignite a bulb I haven't tried it yet, though I know it will work. I've tracked down an electronic ballast that will work for these easy to find bulbs but this gets away from my original purpose; getting better CRI out of my desk lighting. I may grab the ballast since it is cheap but it is a low priority right now. Just wish the listing was correct, I was looking forward to a high CRI and high color temp lamp.

I've scored a find on a ceiling mount 175W ballast/fixture combo that if I win I'll use to replace the horrid ceiling lighting in my room and put that 175W 3900K DX lamp to good use.

I'm still watching a listing for the Twin-Arc 175W 22000K MH lamp. I emailed the seller asking for ballast info and they said "it can use either probe or pulse start ballasts" but they are incompatible both directions; all MH bulbs will work on pulse start ballasts but only probe start bulbs work on probe start ballasts. This means that the bulb in question -should- be probe start, but none of the photos show a starter electrode! Not going to pull the trigger on it until I know it is probe start compatible as I have a 175W probe start ballast on my shelf!

I asked the seller of the inexpensive 20000K 175W MH bulb which that bulb uses and they stated they did not know and said the picture could be "unaccurate" (sic). Sheesh.

It is a travesty I see arise in all aspects of life; the inability to see the (beautiful) complexity inherent. Most see only one simplified view; "all bulbs are the same, it's just light". You will miss more than you could imagine if you lack the initiative to see the diversity in front of you.

Update:
Found a 175W 22000K MH probe start lamp for <$20 and nabbed it. Got the ballast for the pulse start 100W bulb too since my mother in law wants me to install it in the car garage.

Fired up that 100W Pulse Start bulb with my 2.25kW SSTC XD
 
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Cyparagon

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It seems it is hard to find probe start MH bulbs under 400W.
250W and 175W are common. I don't think they come any lower in probe-start. Look for 175W explicitly, as this wattage is almost exclusively probe-start.
 

Sigurthr

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@Cyparagon I think you may be right about the lower limit on probe start lamps. It seems strange that a cheaper bulb needs a more expensive ballast, though magnetic ballasts for high wattage bulbs makes sense. Certainly doesn't make getting into house friendly MH lighting easy unless you come upon a cheap used electronic ballast like I did.

Aye, 175W seems to be the way to go. Can't wait to see the 22,000K bulb fire up and mount my DX Hg on my ceiling. Not sure what I'm going to do with the blue one yet, maybe yard accent lighting, haha.

Oh man those self ballasted lamps are nice. I could definitely put those to use, even if 160W is a bit bright for standard light use.
 
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Cyparagon

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Nah, it's only marginally brighter than a standard 100W. I think your quote got messed up, by the way. Did I say that? I don't remember saying that.

csshih, they're being pretty picky about warm-up time. It might be 5 minutes to 90%, but it's 0 minutes to 70%.
 

Sigurthr

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Haha yes, the woes of using this forum on a phone; things get screwed up! Fixed it.
 

DashApple

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Inside the 1kw Self ballasted Bulb -


SAM_1081 by TwirlyWhirly555, on Flickr

trying to find more of these bulbs , But they seem rather hard to get ahold of now , Will try and get a self ballasted 160 W reflector one as you can see the arc tube and filament , May try and snap up a 1kw reflector mercury lamp or Normal 1Kw Type .

I have a 250 W mercury lamp aswell , nice red glow on startup :D


SAM_1101 by TwirlyWhirly555, on Flickr

And 400 Watt UV black light mercury lamp :p


SAM_1115 by TwirlyWhirly555, on Flickr

Next to get would be a 2 Kw MH lamp , But that's over £400 for lamp , ballast , ignitor in the UK :S
 
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Sigurthr

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That red glow on startup is from the phosphors glowing in the shortwave UV while Hg pressure is low. My 175W does the same, it's pretty cool .

Where on earth did you find that 400W Hg UV lamp?! I'd love to get a notch band pass filter for the 435nm Hg line and place it in front of a low power Hg lamp for accent lighting, but it looks like there is 435nm coming though the wood's glass of your lamp! That would be a lot easier and cheaper than an expensive filter and fixture!

I've found cheap 1kW Hg and MH lamps from LSE inc. but I don't remember if they were reflector or ballasted or if they ship overseas.
 

DashApple

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That red glow on startup is from the phosphors glowing in the shortwave UV while Hg pressure is low. My 175W does the same, it's pretty cool .

Where on earth did you find that 400W Hg UV lamp?! I'd love to get a notch band pass filter for the 435nm Hg line and place it in front of a low power Hg lamp for accent lighting, but it looks like there is 435nm coming though the wood's glass of your lamp! That would be a lot easier and cheaper than an expensive filter and fixture!

I've found cheap 1kW Hg and MH lamps from LSE inc. but I don't remember if they were reflector or ballasted or if they ship overseas.
Yeah :D , Ebay I got two of them for £30 , disco shops sell them online sometimes , 400 Watt is the largest size mercury blacklight I have come across so far .
 
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