My little experiment
My little experiment
I've been struggling with the bulb choices for a couple of months now. I have three newer IceCap 400W ballasts with SE Lumenbright pendants. I've run the Radiums in the past and while I like them, they are just a little bit too blue for me. Actually I think they make the colors pop just a little bit too much- a tiny bit unnatural for me.
I've seen various comparisons here before but problems were:
a) they used a different ballast than mine
b) they used a differnt wattage than mine
c) they used old bulbs compared to new bulbs
d) they used different colors than what I was interested in
As you know bulbs will have different performance depending on ballast, wattage, age and spectrum so lots of apples and oranges here...
So I decided to spend some time and figure some of this out for myself. I'm not Sanjay so my goal wasn't to provide answers to every situation, just ones that could be applicable to me. In particular, I'm cheap and interested in some of the cheaper bulbs so I focused on the Plusrite line hoping that one of them would work for me. I used a few brand name bulbs I had laying around or borrowed purely as a baseline.
Here's what I had to work with (all SE 400W):
New Radium
New Ushio 20k
New Plusrite 14k
New Plusrite 20k
13 month old Aquamckzo 20K (from trust_deals on eBay)
Even though it's old, I included the eBay bulb because I have a decent recollection of what it looked like when it was new. Ignore that data point if you want a more pure comparison.
Here's what I did:
Very simple visual comparison with just a few quantitative data points. I had the Radium as the primary control on the right side. On the left, I switched the bulbs out. I took PAR measurements at 6" and 12" underwater. The reflectors were 17" above the water.
To get the measurements, after a 30 minute burn in, I moved the PAR sensor around at the appropriate depth until I got a peak reading. I eyeballed the bulb in the reflector and didn't do anything fancy to ensure the bulb was perfectly centered in the reflector. Also, on the left side, the 12" measurement can't be compared to the 12" measurement on the right side. My rockwork got in the way so it may be off. However, among the left side measurements, the 12" sample should be fairly comparable.
Control: Radium PAR readings: 610 (6") and 430 (12")
Aquamckzo 20K vs. Radium
Aquamckzo PAR readings: 430 (6") and 330 (12")
It should be noted that the Aquamckzo bulb was significantly brighter and bluer when new
Plusrite 14k vs. Radium
Plusrite 14k PAR readings: 778 (6") and 560 (12")
Plusrite20k vs. Radium
Plusrite 20k PAR readings: 477 (6") and 350 (12")
Ushio20k vs. Radium
Ushio 20K PAR readings: 530 (6") and 382 (12")
PAR Summary 6" 12"
Radium 610 430
old Aquamckzo 20k 430 330
Plusrite 14k 778 560
Plusrite 20k 477 350
Ushio 20K 530 382
Observations: The Plusrite 20K gave a comparable color to the Radium but was noticeably dimmer. The Ushio 20K was actually bluer than the Radium which was whiter in comparison. The Plusrite 14K was slightly whiter than the Radium. The Aquamckzo 20K was yellower and dimmer than the Radium but given it's age, that is not a surprise. When it was new, the Aquamckzo 20K was less yellow but still more yellow than the Plusrite 14K. I had a new Aquamckzo 14K but didn't bother documenting it as it was comparable to a Ushio 10K and not what I wanted.
Conclusion: From blue to yellow coloration, on an IceCap 400W ballast, I would rank the bulbs in the following order.
Ushio20K
Radium
Plusrite 20k
Plusrite 14K
Aquamckzo 20k
Aquamckzo 14K/Ushio10K
However the Plusrite 20K, while similar in color to the Radium and 1/6th the price, was severely lacking in PAR. It had output similar to a 9 month old Radium. A secondary conclusion is that the Aquamckzo bulbs, while decent in PAR have very different spectral output than their labels would indicate. Get a 20K if you want 14k color, 14k if you want 10K, etc.
Based on the above, I'm going to go with Plusrite 14K bulbs for now. They seem to be the right color and intensity for me. Not bad for a $13 bulb!!! As a second choice, I would go with either Radiums or Aquamckzo 20Ks depending on if I wanted to go more or less blue.
It should be remembered that this experiment was done with only one bulb for each specimen. Any variation between identical bulbs in production is not addressed. Also, it is unknown what will happen over time as these bulbs age.
