andrewwynn
Flashlight Enthusiast
Being fascinated by high-output lamps, and the Mag100 project (kicked off by Tom (NikolaTesla) and his desire to have a home-brew USL-like light and starting with a 100W westinghouse lamp that we could direct-drive from 12AA cells.. things naturally progressed to the osram 64625 lamp.
It has been quite a bit of a challenge to get this little puppy to run, but found a magic combination that works brilliantly well..
11xGP2000 cells and the hotdriver set to 12.5V for a nice round 2700L out the front and 94% efficiency.
I finally figured out why my spreadsheet numbers just weren't calculating just right.. by setting the regulator to 12.0V and actually measuring the wattage of the lamps rather than assuming when they say they are 100W they mean it..
The 625 lamp pulls 9.25A at 12V.. or 111W.. the 138 lamp pulls 8.76A at 12V or 105.1W..
now all the numbers are working out with the formulas properly.. It was bugging me that my math never worked out, but it was the BASELINE that was off..
I run the 138 at 13.2V and it always would measure in the 9.2A+ range not the 8.78A value that the formula was providing.. now the formula predicts 9.23A which is almost exactly what is measured.. all is right in the world.
So.. back on topic.. the comparison:
Doing a ceiling-bounce test confirms they
1) are very very VERY bright, oMG.. and
2) very close to the same output. what's a couple hundred lumen?
Beamshot:
The 625 on the left and 138 on the right.
The picture does NOT do justice to the fact you are looking at over 5000L of light bouncing off that wall.. it's pretty much like looking at the headlights of an oncoming bus!
The rest of the beams can be found here and here.
Looking at the comparisons..
Base output of 520more lumen out the front and 200 higher CCT really had me leaning in favor toward the 625, and the driving force to try out the lamp! Not to mention the extra 5.8L/W efficacy.
Since they are rated both for 50 hr lifespan, i am very surprised that we can barely get away with 16 and 7% overdrive.
So.. after blowing up a few bulbs we settled in on 12.5 or 12.6 being very happymaking for the 625..
The Vbat and LDO figures represent the voltage required at the battery to get the Vbulb to the lamp and the LDO is the voltage drop on the regulator FET to keep things happy.
Notice that both lamps run at about 120W ± 2W.. amazing.
Notice that the overall output is slightly higher on the 625, but that the CCT is 146 higher and definitely noticeable.
what makes me like the 625 more than the 138... is that the spot doesn't have that tightly defined circle that you can't eliminate even with a stippled reflector in the 138.. you get a big monster spot of just about 50,000 lux of light.. so has about the throw of a typical Mag85 but with 3-4x the spread!
As shown in the beamshots on the Mag625 thread.. the throw is good for a half a block EASY. Basically.. you can't see things w/o binoculars as far as the lamp will illuminate.. so you really don't need more spot than it has, so it's the best of both worlds and my new favorite lamp for sure.
The 138 has been running a good long time.. i've never blown one, though mine is frosted something fierce inside.. it's milky-white.
Time will tell how close the hour life figures work out, but i'm kinda liking the idea of double the bulb life... me thinks i'll be very happy with my Mag625.
I've decided that it only makes sense to use the similar nomenclature we all use for the likes of the "mag85'.. but to avoid possible confusion with the WA lamps and point out the lamp is different.. using 3 digits instead..
So the Mag100-138 is now called the "Mag138" and the Mag100-625 is not called the "Mag625".
When i figure out how to shoehorn 11 x 4/5A cells into a smaller light than a 3D host which is a nobrainer-fit btw.. fits great.. then i'd use my 'shrinkydink' nomenclature like the M85 or the M66 and call it the M625 or the M138.. or possibly the M120 (watts).. using either the 138 or the 625 lamp..
Ok.. snubbed the other major problem i had with the 625 and have #2 running, and more and more i'm in-favor of the 625's bigger, bolder beam. Spotting 500' is fun once.. but lighting up everything from here to 300' away is far more useful.
beamshot comparison: 250' to a building
Here is the 62138 running at 13.2
Here is the 64625 running at 12.8..
A little too hot to handle.. the bulb did not last too long, but i think that was due to another problem, so i will re-investigate running that hot once i get some more time on the lamp/host. It's very nice to have a WORKING light!
Tom, myself and many others are beginning to realize that that softer focus, flood-like beam is much more useful in most cases, and i would love to see some feedback what people think.
Realize, that the 625 with a stippled reflector still has more LUX than a Mag85! and nearly 4x the light output to boot! So consider that with your feedback.
-awr
It has been quite a bit of a challenge to get this little puppy to run, but found a magic combination that works brilliantly well..
11xGP2000 cells and the hotdriver set to 12.5V for a nice round 2700L out the front and 94% efficiency.
I finally figured out why my spreadsheet numbers just weren't calculating just right.. by setting the regulator to 12.0V and actually measuring the wattage of the lamps rather than assuming when they say they are 100W they mean it..
The 625 lamp pulls 9.25A at 12V.. or 111W.. the 138 lamp pulls 8.76A at 12V or 105.1W..
now all the numbers are working out with the formulas properly.. It was bugging me that my math never worked out, but it was the BASELINE that was off..
I run the 138 at 13.2V and it always would measure in the 9.2A+ range not the 8.78A value that the formula was providing.. now the formula predicts 9.23A which is almost exactly what is measured.. all is right in the world.
So.. back on topic.. the comparison:
Doing a ceiling-bounce test confirms they
1) are very very VERY bright, oMG.. and
2) very close to the same output. what's a couple hundred lumen?
Beamshot:
The 625 on the left and 138 on the right.
The picture does NOT do justice to the fact you are looking at over 5000L of light bouncing off that wall.. it's pretty much like looking at the headlights of an oncoming bus!
The rest of the beams can be found here and here.
Looking at the comparisons..
Base output of 520more lumen out the front and 200 higher CCT really had me leaning in favor toward the 625, and the driving force to try out the lamp! Not to mention the extra 5.8L/W efficacy.
Since they are rated both for 50 hr lifespan, i am very surprised that we can barely get away with 16 and 7% overdrive.
So.. after blowing up a few bulbs we settled in on 12.5 or 12.6 being very happymaking for the 625..
The Vbat and LDO figures represent the voltage required at the battery to get the Vbulb to the lamp and the LDO is the voltage drop on the regulator FET to keep things happy.
Notice that both lamps run at about 120W ± 2W.. amazing.
Notice that the overall output is slightly higher on the 625, but that the CCT is 146 higher and definitely noticeable.
what makes me like the 625 more than the 138... is that the spot doesn't have that tightly defined circle that you can't eliminate even with a stippled reflector in the 138.. you get a big monster spot of just about 50,000 lux of light.. so has about the throw of a typical Mag85 but with 3-4x the spread!
As shown in the beamshots on the Mag625 thread.. the throw is good for a half a block EASY. Basically.. you can't see things w/o binoculars as far as the lamp will illuminate.. so you really don't need more spot than it has, so it's the best of both worlds and my new favorite lamp for sure.
The 138 has been running a good long time.. i've never blown one, though mine is frosted something fierce inside.. it's milky-white.
Time will tell how close the hour life figures work out, but i'm kinda liking the idea of double the bulb life... me thinks i'll be very happy with my Mag625.
I've decided that it only makes sense to use the similar nomenclature we all use for the likes of the "mag85'.. but to avoid possible confusion with the WA lamps and point out the lamp is different.. using 3 digits instead..
So the Mag100-138 is now called the "Mag138" and the Mag100-625 is not called the "Mag625".
When i figure out how to shoehorn 11 x 4/5A cells into a smaller light than a 3D host which is a nobrainer-fit btw.. fits great.. then i'd use my 'shrinkydink' nomenclature like the M85 or the M66 and call it the M625 or the M138.. or possibly the M120 (watts).. using either the 138 or the 625 lamp..
Ok.. snubbed the other major problem i had with the 625 and have #2 running, and more and more i'm in-favor of the 625's bigger, bolder beam. Spotting 500' is fun once.. but lighting up everything from here to 300' away is far more useful.
beamshot comparison: 250' to a building
Here is the 62138 running at 13.2
Here is the 64625 running at 12.8..
A little too hot to handle.. the bulb did not last too long, but i think that was due to another problem, so i will re-investigate running that hot once i get some more time on the lamp/host. It's very nice to have a WORKING light!
Tom, myself and many others are beginning to realize that that softer focus, flood-like beam is much more useful in most cases, and i would love to see some feedback what people think.
Realize, that the 625 with a stippled reflector still has more LUX than a Mag85! and nearly 4x the light output to boot! So consider that with your feedback.
-awr
