150 watt DE MH lamps compared

[MadTownMax]

Very true, with the exception of substantial differences in the performance between ballasts and bulbs of similar spectrum. Not to mention the vast differences in reflector efficiency, etc.

In the best of all worlds you would have data to determine, spectrum, PAR, reflector coverage, reflector efficiency, ballast efficiency, and ballast/bulb interaction. This test is only 2 or 3 of those pieces. Spectrum has been tested by Sanjay Joshi in the past and I'll be offering the bulbs I own for testing as his time allows.

Hope that helps.

Well, if we really want to get into the nitty gritty of things, anyone who posts results should also post what kind of error is associated with those results, due mostly to equipment used, and it's respective accuracy.

Once we have this data we will still need multiple testers (not just sanjay, though he does deserve a lot of credit for his work ) to test multiple bulbs, so that we can assess which bulbs are CONSISTANTLY well made.

With any one of these tests, I'm speculating that you can get at least a 5% error, due to equipment, (so results that show that one bulb has 5% higher output than another might as well say that they are the same)

I have not the slightest clue what differences there may be between different bulbs of the same brand/watt/K-temperature, -hopefully not much, but it would be nice to know - just testing a few would might turn out to be a real eye-opener :eek1: can't wait to see those results.



Just a few wrenches to throw into the old testing regime

 

[JB NY]

I think it is best if you take with a grain of salt, any difference under 15%. Manufactures for the most part claim this to be the margin of error between lamps of the same brand.

 

[electric130]

With any one of these tests, I'm speculating that you can get at least a 5% error, due to equipment, (so results that show that one bulb has 5% higher output than another might as well say that they are the same)

Sanjay puts the numbers even higher:

I personally tend to ignore differences within 10% of each other. Its the larger differences that are more indicative of the difference between lamps. Ofcourse you also have to remember that lamps with similar PPFD values can have very different spectral outputs.


sanjay.

this was over on page 26 of JBNY's 250w thread.

 

[JB NY]

I think most of the issues have been cleared up already. Even being able to compare these tests to Sanjay's have been settled. I had Sanjay test most of my lamps, and using the inverse square formula (posted in the other thread) most of his readings were spot on to the ones I did.

I very confidant that these tests Scott is doing will be just fine.

 

[MadTownMax]

Thanks for the input electric and JB.

15% difference between the same bulbs!!!!! - kinda scary, that's the sort of thing that makes me want to go buy these bulbs at a store w/ a lux meter, so I can check a few and get a good one .

 

[JB NY]

Even that wouldn't work. If you test a brand new bulb, over the first 100 hrs you will steadly watch the output go down until it settles at a number.

 

[electric130]

Even that wouldn't work. If you test a brand new bulb, over the first 100 hrs you will steadly watch the output go down until it settles at a number.

and they all will still "settle" differently.

 

[reefman33]

sounds great, any estimate when you will start posting figures?

 

[ExtremeReefer]

Good thread, tagging along for the ride......

 

[traveller7]

sounds great, any estimate when you will start posting figures?

Looks like this weekend for the first few. Expect to be dealing with format, issues etc, early on. Most of the bulbs are still burning up to the 100+ hour marks over tanks on real world 6-10 hour schedules.

Based on Joe's experience and input, I spent quite a bit of time making sure the process of swapping bulbs, ballasts, operating temps, etc., did not change results. Lots of quick disconnects, ballast mounts, box bottoms later, it looks like it is finally idiot proof and giving consistent results. It was sure nice to have some well burned in loaner bulbs from saltyseaman to help out with this process.

Representative photos are a challenge until my Coolpix 4500 is returned from repair.

I did take photos of all the bulbs and will be talking to an RC'er about hosting the pics for a consistent and comparative view

Unfortunately, I have lots of real life to work on until this weekend.

Cheers.

 

[traveller7]

Spent most of today laughing at myself and time wasted.

Turns out that for all the talk about "leveling" it really does not make that much difference at 8" distance

Now we are having fun

 

[traveller7]

Now we are not having fun.

16 hours of burning, etc and I need to add a heat sink behind the 150 DE bracket. The wood is too close and has blackened through the paint and smells of burning. These jokers are hot, very hot.

I am looking at a piece of ceramic tile or black foil at the moment.

Off to home depot before they close.

After mod, I'll need to rerun a 2 bulbs to make sure I have not made significant changes in readings.

Update tonight.

 

[reefman33]

i cant wait.

 

[traveller7]

........Off to home depot before they close......

That was fruitless. They had material, but nothing that looked like it would work in the manner necessary, so.....

I painted an old IceCap heatsink from an IC660 in flat black. After it dries, I'll check it for values against the flat black wood to see whether it makes a measureable difference.

It looks like it will work well, but the ability to easily go from 70wt/150wt bulbs has left the building

 

[jauringer]

^

 

[reefman33]

coem on give us just a little bit. one reading? anything please

 

[traveller7]

coem on give us just a little bit. one reading? anything please

A 6 month old 120wt Phillips Agro-Lite has a PAR reading of 35 @ 8" from the bulb

Really, and I have been using them instead of these 6K 150DEs? The delays are painful for me as well

I would love to share the readings just to get going, but they are with 3 different backings. The new heatshield was acting as a reflector, so I painted it in a flat krinkle coating and will check it tomorrow. Until we get a good baseline it really is a pointless comparison of bulbs The big mistake on my part was not working out the kinks prior to posting anything at all. My apologies for that.

More news:

One of the mods, DJ88, has offered to help out on handling the posting, so this thread will be for discussion only and the results will be posted in a new thread which will be closed. DJ will be adding the updates as I send them. Good idea electric130

I have some more good news, it does not appear I am going to burn down my house and I just called Geico.

Have a great night and hang in there, the good stuff is so close it can be tasted.

 

[electric130]

One of the mods, DJ88, has offered to help out on handling the posting, so this thread will be for discussion only and the results will be posted in a new thread which will be closed. DJ will be adding the updates as I send them. Good idea electric130

great, it will be easier and quicker to get results for people who just want to see which one is "better." although, that's always argueable, which in that case they can come here. :lol: thanks for all your hard work on this. we all really appreciate it.

 

[reefman33]

dont worry about the delays. these things always have kinks to work out i am just really excited to see how these things compare to 250watt bulbs and how much light they really put out.

Glad you wont be burning anythign down lol

 

[gcarroll]

Just wondering if you will be using the UV shield in your test?