Par 38 LED spotlights

JTL, if the graph is labeled correctly, the numbers on the side indicate the width of the light spread, which mimics the length, as it should since it is a circle.

The depth is constant and marked as 14".

The cone of light created by each optic is very similar and all have an output diameter of about 14" . The only major differences are the subtle changes of intensity on the outer edges and major changes to the center. Which leads to me to believe the wider optics acts as a "dimmer" instead of a "wider reflector" since it diminishes output rather than spreading or equalizing the light.

Just want to make sure I am reading this correctly before ordering :D
 
I think the differences between the different optics is more noticeable the farther away you are for the light. At 14 inches of depth, there is not a lot more increase in intensity at the periphery, that's true. at 20-30 inches of depth, there is a significant difference. If your plan is to mount the PAR38s at 14 inches above the bottom, then the higher degree optics don't increase the PAR in the periphery that much, it's true.
 
Spleen,

I took another look at the plots and it looks like the results are the same. The outer edges are dimmer on the wider optics no matter the distance. Which makes sense as the brighter center portions when close just expand when moved farther away.

No matter the distance, the change in optics seems to have a large affect on output with a minute change in spread.
 
I wouldn't call it a minute change in spread since at around 7.5 inches away from the bulb, the PAR nearly doubles from the 40 degree optic to the 80 degree optic at 20 inches of distance. Nevertheless, you are correct that the outer edges will continue tp be dimmer than right under the bulb. We're sort of discussing semantics at this point.

Maybe you'd like to tell us a little about your tank and lighting plans so we could make some recommendations based on our experiences?
 
i already posted up PAR plots and numbers for these bulbs i don't know why people are opening their mouths when proof is in the data

1 inch under the water under a 40 optic PAR38 about 6-7 inches from the bulb i was getting a PAR of 1500, 33 inches away from the bulb i get a PAR of 180 in the center of the bulb which is more than enough to keep sps

the issue's with LED's isn't PAR or their effeciency it's getting SPS coral colors to be vibrant and i plan to solve this with my custom bulbs

i get my 4 custom PAR38's tomorrow, i'll have the first new pics up this friday, stay tunned
 
i already posted up PAR plots and numbers for these bulbs i don't know why people are opening their mouths when proof is in the data

1 inch under the water under a 40 optic PAR38 about 6-7 inches from the bulb i was getting a PAR of 1500, 33 inches away from the bulb i get a PAR of 180 in the center of the bulb which is more than enough to keep sps

the issue's with LED's isn't PAR or their effeciency it's getting SPS coral colors to be vibrant and i plan to solve this with my custom bulbs

i get my 4 custom PAR38's tomorrow, i'll have the first new pics up this friday, stay tunned

With all due respect beeker, I don't think you can "solve" or "prove" anything with a single case study and further discussion about PAR/spread will be nothing but beneficial. That being said, I am looking forward to seeing your results with the new bulbs and I think your experience will contribute significantly to the cumulative set of information available for the PAR38 LEDs. Just remember that there are always limitations with an (n) of one in experimental design.
 
benny the only issue's i've found with these bulbs is color on 1/4 of sps is bland or dull looking, IMO this is cause the cool white overpowers the royal blue (i have 12k's with 40 optics)

by adding 4 custom bulbs that are heavy in 470nm blue along with 1 neutral white to balance the blue out as well as add another spectrum i do believe i can solve the sps color issue

these bulbs are awesome and i've only had compliments on my setup from everyone that has seen it in person, believe me i know it will take time to get the results but i do believe i can figure out by myself what is cause the sps color not to be there on 1/4 of what i put in my tank

lps/Zoa's clams and chalice all continue to have great color and growth under led all my stuff looks great minus about 4-5 sps pieces out of 20

so saying i can't prove anything with 1 case study doesen't mean a thing, look at all the people that jumped on the Zeovit bandwagon when it started, all it took was 1 person to say that they got great results with it and then everyone jumped on, i don't care if people like or dislike LED i know where lighting tech is headed and it ain't T5 or MH anymore, lol

i guess at the end of the day i could have been like everyone else and just threw a MH on my setup but then again i'd be dealing with heat/ yearly bulb replacement and the electric bill

I'm reshaping the wheel and i like what i've got so far

that being said my tank is only around 4 months old at most and will be another 8 months till it hits maturity, by that time i'll have all the color issue's worked out and my corals will be kicking
 
Seems to me the par/spread issue really shouldn't even be a debate. The same bulb will deliver the same results all things being equal. If we are talking about what it takes to make the corals happy and look good that is open to discussion.

Beeker, my 50/50 mix of 12k and 20k seems to be working out. The colors are natural without over doing the blue spectrum which I personally think looks a little artificial. I believe you will be about a 50/50 ratio of blue to white after adding the new bulbs. Nice thing is you will be able to highlight the corals that you want with more intense blue. Pics would be nice but I still maintain that it is almost impossible to capture the real look of this lighting.
 
Seems to me the par/spread issue really shouldn't even be a debate. The same bulb will deliver the same results all things being equal. If we are talking about what it takes to make the corals happy and look good that is open to discussion.

That's exactly what I'm talking about, the problem being is that all things are never equal. So even if beeker is successful in coloring up his SPS, those results are not necessarily generalizable to; anyone else's tank, any other species of coral, or even the same coral 5 months from now. There are just too many variables to draw any decisive conclusions (i.e. "proof"); the best we can do is make informed guesses.

Beeker, I hope there was no offense taken from my earlier post because none was intended :). I have been following your build from the beginning and think what you are doing is awesome. It's partly because of you that I will most likely be giving these bulbs a try over my new build.
 
Benny,
My point was that the bulb specs like par or coverage will be the same for everyone providing we are comparing the same bulb and optics at the same distance/water depth. I agree that effects on the corals can vary due to many other variables. I also think this thread has been a healthy debate and a wealth of information.
John
 
no offense was takin benny i've been in the hobby long enough to know their are different strokes for different folks, lol

but at some point you get tired of all the MH and T5's thinking they have the cream of the crop over there tank

sure Led still has some bugs but even T5 and MH setups had their bugs in the very begining, and from what i've seen so many companies are jumping on the Led bandwagon it won't be long before we figure out the right color combo of leds needed to keep sps color's vibrant

i'll agree water quality plays a huge role, but from all my experience i've never had an issue keeping my water 100% where it needs to be, this comes from daily dosing Calc/Alk and Mag as well as weekly testing of all 3 along with a 6-10 gallon WC once a week

i've noticed some sps moved into my 200g led tank from a 150w pheonix 14k that have better color under the leds than they did under the MH, although some pieces have lost color under the led some sps pieces are starting to get their colors back after being under the leds for over a month now, i know things take time weeks/months to figure out, so i'm doing my best to solve what other people haven't taken the time to solve at this point with led

if you get your hands on a PAR38 benny you won't be displeased at all, you may figure out that not all your corals are going to be 100% colorful but then again this is the reason why i'm getting custom bulbs made

if i figure out what other led color is needed to get vibrant sps colors day in and day out then i'll be happy and i would have made it 100 times easier for someone else to do the same thing with their setup

this is all assuming they know proper husbandry to maintain quality water :)

sorry for the novel but hope this clears up my thinking for you
 
I tested my 4) P38 LED's today with the Par meter.

@bulb white 2000+
@bulb blue 2000+

1" below white 2000
1" below blue 1000

6" below white 1500
6" below blue 500

1" below surface white 1000
1" below surface blue 200

6" below surface white 750
6" below surface blue 100

12" below surface white 500
12" below surface blue 25

24" below surface blue and white 75

Ecoxotic 453 Panorama strip

At bulb 1200
1" below 600
6" below 50
1" below water 10
12" below water 5
24" below water 1

Since I have 40 degree optics, the values can change drastically if the meter is outside the cone of light. For instance, @ 6" below the bulb, between the 4 individual bulbs, the meter reads 200. One of the bulbs is a 60 degree and I cannot notice a difference between the 40's and the 60's. Remember, these are spotlights and coral placement needs to be thought out carefully when using them.
My acros are up high, LPS medium, shrooms, zoas, montis from low to bottom of tank. I have several corals directly on the bottom in the 20-50 zone and appear to be doing fine. The big derasa clam is in this low par zone and opens fully.
If I base the corals appearance vs. the par readings, then I can only assume that what we know about PAR and coral growth must be different when using LED's.
 
What is
@bulb white ?
@bulb blue ?

Does this mean white = 12K bulbs and blue = 20K bulbs ?

It simply means that I placed the meter directly under the blue bulb and directly under the white bulb. 12k or 20k makes no difference. It's kinda difficult to get a true par reading under the cluster, so I went for individual bulbs.
 
I finally received the 3 Ecoxotic bulbs (21w) last week from Premium Aquatics but didn't get a chance to hook up till last night. I've been to homedepot and lowes but didn't find any track light I like to so ended up getting 3 clamp lights for the time being.

According to PA the bulb should be: EX-6850 PAR38 21 watt LED Aquarium Lamp, 12,000K but I just noticed on the box the label say it's 6500K. Need to check with PA on this. For the folks that got the Ecoxotic bulbs does your box say 6500K?

Photo0004.jpg



The light is 15.5" from the water surface and center of bulb is 11" from each other.
Sorry for the poor quality as this was taken with the cell phone:
main pump off
http://s75.photobucket.com/albums/i287/reeftankpix/?action=view&current=LED1.mp4

main pump on
http://s75.photobucket.com/albums/i287/reeftankpix/?action=view&current=LED3.mp4

I like the shimmering effect like the MH but without the heat. It's currently mounted over a 120g sump (48x24x24). I find that I would need at least 6 bulbs (3 in the front and 3 in the back) and 8 would be better otherwise too many dark area. Right now the 3 bulbs are in the front and I supplement with t5 in the back. I would love to get some for the 180g but it would be too expensive to do it now.
 
So the label says that your light bulb consists of 3 x 6500K white LEDs and 2 x 455 nm blue LEDs. The mix of those 5 LEDs will likely result in a 12,000K look so I think you got the right bulb.
 
So the label says that your light bulb consists of 3 x 6500K white LEDs and 2 x 455 nm blue LEDs. The mix of those 5 LEDs will likely result in a 12,000K look so I think you got the right bulb.

Thanks for the info...I was thinking the combo of 6500K and the 455nm would result in lower and not higher Kelvin.

One other question: the spec also say the bulb consumes 21W, assuming the 5 leds are 3W each so does the integrated ballast use 6W?
 
i got a question... im trying to find out how i can run these bulbs. i know they have the standard e26/27 threading, but how can you find out your fixture uses those type of bulbs?

would they work on a clip on desk lamp?
 
Thanks for the info...I was thinking the combo of 6500K and the 455nm would result in lower and not higher Kelvin.

One other question: the spec also say the bulb consumes 21W, assuming the 5 leds are 3W each so does the integrated ballast use 6W?

Yes, there is some electrical loss in the ballast / electronics of the bulb.

i got a question... im trying to find out how i can run these bulbs. i know they have the standard e26/27 threading, but how can you find out your fixture uses those type of bulbs?

would they work on a clip on desk lamp?

Yes, they would, providing that the outer shell/housing of the clip on desk lamp didn't block or cover the heat sink of these bulbs. Sometimes, a little modification is required.
 
got my custom 4 cool blue led and 1 neutral white led 60 optics PAR38's

here's the pics, this is with the 4 customs and 8 12k bulbs, color in person is incredable

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my main red planet colony, starting to get it's green back and the new custom bulbs should also help out a lot with color
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