Paul C. Buff, Inc. Technical Forum

I have received the Vagabond mini and in the I read in the instruction manual that a new modeling lamp of 50W is going to be developed to be used with the Vagabond mini. Thus, I was wondering why a LED light has not been considered for such purpose. The LED does not need lots energy and it is daylight calibrated.
Just a thought.

I think you might be getting confused with the 25watt bulb designed for the Einstein strobe. Yes it is the same type of JD15 type bulb that is found in the 250 watt version of the einstein but consumes less energy and isn't as bright. I do agree that there should be a LED version for the einsteins and tried searching for compatible LED lights

http://cgi.ebay.com/ebaymotors/ws/eBayI ... OTORS:1123

There are about 3 different types of LED bulbs that i found, but i didn't want to take a risk just to find out that the bulbs aren't compatible.

"This bulb has the BA15D base, so should be compatible. Note that this bulb runs on 12V AC or DC. It is not dimmable. Please double check bulb dimensions to make sure that it fits your application.

Regards,
LEDwholesalers"

If you wanted to use LED lightbulbs with the vagabond mini, you absolutely can. Just get a lamp socket and slap on a LED bulb. However there is no LED bulb that will work with the einstein at the moment.

3.6W LED will only produce about 14W halogen equivalent light level, the base won't fit an Einstein, and 12V lamp cannot be used - it will die instantly. Requires a separate power supply to get the 120V down to 12V.

Also, there is the question of whether LEDs in this close proximity to the flash tube can handle the heat emitted by the flash tube.

LEDs will ultimately serve this purpose but have IMHO a few years to go.

I had already ordered the led bulbs when i had posted and tried putting them into the einstein.... what happened next was incredibly shocking: the fuse blew up making a loud firecracker-like POP that left me in complete awestruck :o The plastic lid from the fuse popped off due to the pressure from the fuse explosion but i'm happy to report that the einstein was ok, just a blown fuse, an einstein that is down for a week, oh, and a bruised ego. (I have two einsteins and switched the fuse just to make sure the lightbulb didn't brick the einstein). it's a good thing i didn't have a wedding to shoot this week but i will definitely check with paul before i try anymore lightbulb endeavors.


led bulb in question


What triggered my decision to purchase the LED bulb: seeing the similarity of the base of the 25 watt bulb and the led bulb purchased on ebay.


comparison between the led bulb, the stock bulb, and the 25 low output watt bulb



stock setup.



led bulb fits perfectly centered in the einstein.



side shot


glass dome fits over the led bulb.



the blown fuse amongst the lightbulb test.... sad day.

I really want to find a LED substitute for the einstein because the stock modeling bulb generates too much heat to be used for long periods of time.

This is what I wanted to achieve (Note, this is a bike led light Magic Shine hidden inside the plm, sitting on top of the einstein not the led bulb. I recommend this light if you do night biking http://www.amazon.com/Magicshine-MJ-808 ... 398&sr=1-2)




close to the color balance that I was seeing in real life.

auto white balance with the 5d2

exaggerated blueish tones to get an idea of what kind of color the led bulb was emitting.

You can't put a 12V lamp in a 120V socket and not expect sparks to fly.

At this point, I would guestimate a 100W equivalent LED, if one existed to fit Einstein, would cost us about $200 and sell for about $400. A 1.5W LED alone rated at 50 lumens per watt (Cree) sells in large quantities for over $3. You would need 50 of these, plus power supply to run them from 120VAC.

Also, the low wattage Einstein bulb (made specially for us) is 35W 100V and actually burns at 116V in Einstein. One's we have tested have passed 1000 hours at 120V and still burning. They put out pretty decent light levels.

Maybe the LED technology is close to being commercial: http://touch.slate.com/slate/#!/entry/t ... bulb,55732

$20 for a 60W equivalent is cheap. The 100W is likely to be too big to fit in the center of most flashtubes.

As I said, LEDs are the future of lighting, but has a way to go . . . but this looks like good progress.

And you probably still have the heat issue to contend with... heat kills LED's - on a monolight or in household fixtures. That bulb is interesting though in that it appears that the bottom is a big heat sink and the the globe is filled with a liquid coolant. It is surprising that is is only $20 given how much material and manufacturing go into it and how small the market is at the moment.

Heat from the flashtube is a definite unanswered question. The heat sink is to remove the heat produced by the lamp itself . . . adding the flash tube heat is not considered by the lamp manufacturer. As for the market, a 60W equivalent for $20 is quite attractive, when the life and energy consumption is considered. I just paid $35 at Lowes for 35-40W equivalent, and they dim OK. (No, not used in flash units - they won't fit.)