Phillips 5761 WW Shots - First Attempt

[Bob_G]

I got motivated to do these because of this thread where I was extolling the possible virtues of the 5761. jwl asked if I had beamshots of the 5761 and of course I didn't because I've never tried to do any. These are quick and dirty off the basement ceiling, but I think they illustrate the interesting distinctions of the 5761. If I ever get up the energy I want to try some outdoor shots, the only true "beamshot" as far as I'm concerned, but these "spotshots" look like what I'm used to with the respective lights in use outdoors.

The ceiling is basically white.

Canon Powershot 610; M@125; color temp auto. The lights were separated by about 2 feet with the camera between them. About 4 feet to the ceiling for the lights and 5 for the camera.

5761 - 12xCPB1650 in a 6x2 S/P setup; M2-MOP; HotDriver at 7.2
1185 - 9x4/5A; M2-MS; [email protected]
1274 - 8xTitanium 2600; M2-MS; [email protected]
1331 - 3x17760; M2-MS; [email protected]

These seem to be lower exposed than most people's but they look okay to me and I'm way too lazy to do it again. There's been no post processing of any kind except to crop.

5761v1185

5761v1274

1185v1274

1274v1331

The last shot is a "control," to make the similarity obvious between almost identical output lights with different bulbs. My assumption when I decided to try the 5761 was that it would be a 1185 alternative output wise, but indoors it appears much brighter. I'm headed outside later to see how they compare (just got the '85 back today.)

Hope someone finds these useful. The 5761, if you can drive it, is a pretty interesting beam.

 

[jwl]

Bob_G - What reflectors are you using? I'm definitely liking the way the 5761 looks. Hope you get up the 'energy' to try some outdoor shots...

 

[Bob_G]

jwl, the WA bulbs are on in medium stipple reflectors and the 5761 is in a medium orange peel. Getting such a nice spot out of a lightly textured reflector is why I like the 5761 so much I've got a SMO laying around somewhere I'd like to try, but have to ream it first, and that takes energy so ...

 

[OscarO]

Mmmmmm.... booobs......

 

[jwl]

Bob_g - how's that 5761 bulb working for you? have you gotten very many hours run up on it?

 

[Bryan]

Bob_G - What reflectors are you using? I'm definitely liking the way the 5761 looks. Hope you get up the 'energy' to try some outdoor shots...

yeah, would love to see some night shots!

 

[Bob_G]

I just last night put it in a new host. I had it in a 6AAx2 with CPB1650, and now have it in a 2x3 17670 (still [email protected].) Still going strong, and I'm even more impressed with it as time goes by. Not many hours, but awr computed it at 13 hours or so bulb life at 7.1V, so that's twice the life of many of the bulbs we run in hotwires. I was worried it might take a double-click with the Li-Ions, but so far no problem, first click every click (with AW's NEW 17670s.)

I can't remember if I've said this publicly, but this is a very white bulb at this V. Taking a 9x4/5A Mag85 out with it, which has about the same output, the '85 looks yellow by comparison. This is a very white light. It could be a subjective impression because of the strong spot, but i don't think so.

Remember, this is one person's impression, but this is getting to be my favorite bulb. Really tough to drive, never going to get a long runtime solution probably, but it's so white and round and perfectly sized for its power it's almost intoxicating. On the other hand, when I take the '85 out by itself, I love the creamy way the spot and spill blend together (with a MS reflector) and the overall impression is very nice. But, the spot from the 5761 is large enough to provide useful area light and still have better throw than any of the WA bulbs to my eye.

Luckily there's a full moon now, so that's a great excuse to avoid outdoor beamshots for the moment I'll definitely be try some sooner or later though.

 

[xpitxbullx]

I'm running a 5761 out of my M6 and we are talking some serious light output here.

Jeff

 

[jwl]

xpitxbullx - the M6 runs at 6V, correct? So you are running at the spec voltage.

 

[xpitxbullx]

No, The M6 runs at 9V. After the intial voltage sag, the 6V Philips 5761 is being over driven at about 7.2V

Jeff

 

[Illum]

Mmmmmm.... booobs......

how the devil do you get boobs from beamshots....


oh...:lolsign:

 

[Lips]

Bob_G


Would it be advisable to do a tailcap spring mod and tower spring to see if it gets whitter light... Should the pack described below be enough to drive the 5761...





FiveMega Chrome 2D running 5761 instead of ROP bulb that came with it.

6 X 17500 (1100mah cells) in 2s3p setup

More light than the ROP HOLA was putting out but seems a little underdriven. Not as much light as Mag85 or 1500L - 1164 in this setup.

 

[Northern Lights]

The 5761 lamp pulls 5.53 amps with the 7.2 voltage. You only have 2.2 Ah on the pack. That is a load of about 2.51c on the battery pack. There are several threads and good info on CPF that indicate that you could be distressing your Lithium batteries if you excede 2c. I gather these are AW's brand. If so, ask him about the load and if that is not the problem then:

Yes modifying the tower and switch and spring will reduce the resitance and it could be noticable.
https://www.candlepowerforums.com/threads/130965
and you know how to modify the spring. He is a solution to tight fits needing reduced springs.
https://www.candlepowerforums.com/threads/130965

 

[Bob_G]

Just my opinion, but I'd say no, and I'd also say it's not too good an idea to run the 5761 on that setup at all. Your other two are pulling 3A-4A, but the 5761 is around a 6A draw, so you're right at 2C on that battery pack.

If it was me, I'd hotdriver an 1160 at 6.9V in that setup (I have exactly the same thing and it's great.) Not the output of the '85 or '64, but the best beam in the WA lineup for spot integrity. Should be about 660 bulb lumens.

Even driven just right, I think technically the 1164 puts out more lumens than the 5761 - not sure if that would be obvious to the eye though. My 5761 setups are very white and put more light on target than the '85, but beam shape could be the reason, I think they're so close in output you couldn't tell by eye if you could control for everything.

Anyhow, that's not a very good match of bulb and power supply, but the 1160 is tailor made for it if you regulate it.

To give you an idea of how tough the 5761 is to drive, I used to run one in a 6S2P AA setup. This was hotdrivered, so there's a low voltage cutoff. I had to use CPB1650s in it because even with Eneloops, the 5761 sucked them down so fast that the low voltage cutoff would kick in after too short a time not to annoy. It's very demanding.

 

[Lips]

The 5761 lamp pulls 5.53 amps with the 7.2 voltage. You only have 2.2 Ah on the pack. That is a load of about 2.51c on the battery pack. There are several threads and good info on CPF that indicate that you could be distressing your Lithium batteries if you excede 2c. I gather these are AW's brand. If so, ask him about the load and if that is not the problem then:

Just my opinion, but I'd say no, and I'd also say it's not too good an idea to run the 5761 on that setup at all. Your other two are pulling 3A-4A, but the 5761 is around a 6A draw, so you're right at 2C on that battery pack.

6 X 17500 (1100mah cells) in 2s3p setup

That should be 3.3 Ah on pack

Is that still too close to 2C ?

 

[Bob_G]

For me it is Not saying it wouldn't work, it's just a marginal solution. If you were building a light from scratch, there's only two ways you'd do it. Decide on a battery setup, then find a bulb to fit. Or, decide on a bulb and find a battery solution. The 5761 and 2S3P 17500 don't add up in either case for me :shrug: Something else to consider is that to get the output from the 5761 that makes it worth running, you need a battery that will hold a little better than 3.5V under load, and I'd have doubts whether your 17500 setup would do that for very long.

 

[Northern Lights]

Somehow I missed that you were running 3x pair, I calculated a 2x pair. So you are running a 3.3 Ah pack. I am running a 2.6 Ah on 18650. These do not have all the protection of the AW batteries and these run the rig hot, I got an insta-flash already. Now one would believe they should have the same output but the 18650s are running the bulb nice and hot white. I am over the 2c, I took the risk but it seems to be working under the conditions I have now. On another light I have 5.4 Ah pack on NiMh and the bulb outputs are not the same, the 18650s are brighter.

 

[Bob_G]

Based on Silverfox's charts, unprotected li-ions hold voltage at 2C, especially at higher draws, way better than protected.

I found something interesting there, thinking about the 17500 setup. I'm probably missing something important, but it's puzzling to me none the less.

I've always sort of assumed that a pair of cells in parallel was the same as a single cell of twice the capacity - a pair of 17500s in parallel should perform about the same as a single 18650 in other words. Testing this idea with the charts I get a funny result.

Since the charts are all for a single cell, I compared how well a 17500 held 3.5V at 2A (2C) to an 18650 at 4A (2C) within the same brand. The 18650s failed this for every brand - they fall apart at 4A, even though it's the same 2C load as 2A on the 17500. The only unprotected cell with both examples did fine, and the LG looked really nice for the 18650 (only one he tested.)

My methodology or thinking could be messed up here, but if it's not, then there's something going on with high current draw and protected cells, irregardless of capacity. Perhaps there's a "knee" point in capacity of a protected pack where it doesn't matter. My 5761s seem to run fine on 4.8AH li-ion packs. But if a protected 18650 falls on it's face confronted with a 4A load, a 3AH pack at near 6A isn't very encouraging.

 

[Northern Lights]

So that is why my 18650s work so well and at a little greater than 2c. This thread discusses the BatterySpace 18650:https://www.candlepowerforums.com/threads/142805

This is the thread that got me over the 1185 fever, realizing more versitile options.

Thanks again , this time publicly,Erich. I also appreciate the SilverFox link.

I PM'd you about some freakish bulb breaking blundering I did. No, actually I PM'd myself and then forwarded it to you. Somedays you just go in circles and still get lost!

 

[LuxLuthor]

Another useful thread to resurrect.