Latest build, LXP RS or Aspherics for murky waters?

[gav6280]

Latest Head done (Rev 3.0), just passed pressure test to 110M!! Whaooo so pleased, so have now sent it off for anodising.



Battery Cannister all Done, (thanks 350xfire)



Driver wired up and battery selected. (Blue Shark + R/C 5500mah 3 cell LiPo)

And i think ive finally settled on using 4 XPG's because i rather fancy the extra lumen available from them and i already have them laying around from other builds.

So for UK green water diving do you think i would be better ordering:

A) The 21mm aspheric lenses from DX - SKU 13903, which will most likely end up giving me a beam of around 10 to 11 deg using xpg's. (information based on Packhorse getting 8.3 deg using these with XRE's in his original quad mag).

B) LXP REAL SPOT (FA10661) which according to the data sheet HERE, should give me only 3 deg FWHM (So actually 6 deg) and make my final assembly much easier??

If anyone has a direct beam shot comparison of a single dx lens and a LXP-RS both using an XPG emitter, with the same background and settings i would be eternally grateful.

Ive been procrastinating over this for literally weeks, and i just cant make my mind up which option to go far. It's a primary light and needs to have reasonable penetration and signalling capability, but not necessarily be so tight it only lights up the bit immediately in front of you, beacuse it will do a few occasional trips abroad for clear water big wreck diving.

And not forgetting of course the 2 dives a year!! When the viz in the UK is excellent....

 

[Packhorse]

Using XP-G's with aspherics will not give you more lumen than XR-E's with the same aspheric. The XR-E will be tighter and project more lumen ( assuming top bin lumen of each eg R2 vs R5). Because of the beam angle of the XR-E much more light is collected by the aspheric.
In saying that if you already have XP-G's you may as well use them.

I have used that XP-G optic and here are some beam shots. None to compare the DX aspheric though.

http://www.candlepowerforums.com/vb/showpost.php?p=3265822&postcount=106

 

[znomit]

And i think ive finally settled on using 4 XPG's
...
B) LXP REAL SPOT (FA10661) which according to the data sheet HERE, should give me only 3 deg FWHM (So actually 6 deg)

The datasheet is for XP-E, The XP-G will be more like 10deg.

 

[gav6280]

Using XP-G's with aspherics will not give you more lumen than XR-E's with the same aspheric. The XR-E will be tighter and project more lumen ( assuming top bin lumen of each eg R2 vs R5). Because of the beam angle of the XR-E much more light is collected by the aspheric.
In saying that if you already have XP-G's you may as well use them.

I have used that XP-G optic and here are some beam shots. None to compare the DX aspheric though.

http://www.candlepowerforums.com/vb/showpost.php?p=3265822&postcount=106

Yeah thanks pack, like i say ive already got plenty of XPG already here so im just unsure weather ill get a tighter beam with by using Aspherics or Optics, because its looking like either option will end up around 10 deg by all accounts....hmmmm, the choices....

 

[gav6280]

The datasheet is for XP-E, The XP-G will be more like 10deg.

Thanks, that makes it even harder to decide what to go with!!

 

[jspeybro]

I have both optics here, and some (red) xpg's. I'll see if I can make a comparison. Just need to find the battery charger of my camera first :scowl: and make a little support for the DX lens ...

 

[gav6280]

A few side by side comparison shots of the LXP RS Vs the DX Aspheric would be very much appreciated.:twothumbs:twothumbs:twothumbs.

Looking for beam angles, amount of spill, and overall brightness with exactly the same camera settings, distances and background for each to make it a true comparison.

 

[350xfire]

That's nice gav... What are you going to do with the head to protect from corrosion? I ask since I will probably be doing an HAIII run at a local anodizer in a few weeks and if anyone wants in, let me know. Minimal charge.

Thanks

 

[Packhorse]

its looking like either option will end up around 10 deg by all accounts....hmmmm, the choices....

Perhaps, but they will still be very different beams.
The aspheric will have all the light in that 10 degree square beam and probably be more intense.
The TIR will also have spill light out side of the 10 degree beam, be less intense but have more over all projected lumen.

As you say... hmmmm, the choices.....

 

[gav6280]

That's nice gav... What are you going to do with the head to protect from corrosion? I ask since I will probably be doing an HAIII run at a local anodizer in a few weeks and if anyone wants in, let me know. Minimal charge.

Thanks

Dam....It's having a light bead blast and then a thick coat of matt black type II today!! As i cant find anyone in the UK who would do one off's of type III for sensible money.

 

[DaYerk]

Any news about LED and optic? How good is a multi XP-G with LX-P RS?
I Like my single LX-P W200 very much it is like Packhorse says:

XP-G has a larger spot but limited spill. Colour is good

I like the colour too, nice bright white. But will 4 or 6 of them work as good?

What will be better one "big" LED like the SST 50/90 or a multi XP-G?

 

[gav6280]

Any news about LED and optic? How good is a multi XP-G with LX-P RS?
I Like my single LX-P W200 very much it is like Packhorse says:



I like the colour too, nice bright white. But will 4 or 6 of them work as good?

What will be better one "big" LED like the SST 50/90 or a multi XP-G?

Im just looking at a solution of with LXP-RS OR Aspherics from DX, we only need a single Led compariso, as the result will just be 4 times as bright as long as you angle the beams to converge, hopefully jspeybro will deliver the result.

 

[350xfire]

Dam....It's having a light bead blast and then a thick coat of matt black type II today!! As i cant find anyone in the UK who would do one off's of type III for sensible money.

Yeah, it's really hard to find someone to do one offs or they'll do them for the minimum charge which can usually get about 50 heads done. So it's really hard to pay that for just 1 head.

 

[jspeybro]

Im just looking at a solution of with LXP-RS OR Aspherics from DX, we only need a single Led compariso, as the result will just be 4 times as bright as long as you angle the beams to converge, hopefully jspeybro will deliver the result.

Here you are (a friend didn't return the charger of my camera :sigh: anyway, on to the results)
I connected 2 red XPG's (since I only have red ones at the moment) to the same driver in parallel, providing 1040mA, so both LEDs should get about 500mA. The distance to the wall is 2 meter.

On the left is the dealextreme sku 13903 optic and on the right is the Ledil XPG-RS optic.
Note that I used camera settings which did not saturate the red light. In reality you can see a slightly wider spill around the LXP spot but this is difficult to see in this picture.
The yellow line is the line where I measured the intensity profile as shown below:

As you can see, the intensity of both optics is the same. I think it will depend a bit on what you prefer as a spot do decide which optic you like mosts. I didn't measure the width that my camera could see, so I can't calculate the beam angle at this moment.
The LXP optic is dropping of more gradually which may be prefered as you get a little sidespill which may be nice. It's probably also less sensitive to mis-allignment if you want to combine more LEDs to get more power.

hope this helps

Johan

 

[gav6280]

hope this helps

Johan

Bloody, brilliant, thank you and well done! If you were not so far away id buy you a beer.....

Seems to me as suspected there isnt actually that much in it, so to keep my build simpler and actually get the full brightness, not to mention a nicer multi beam pattern, i think i will go for 4 of the RS's.


Edit: Or maybe even 2 of each....

 

[jspeybro]

Bloody

no, just red leds ;-)

brilliant, thank you and well done! If you were not so far away id buy you a beer.....

'Westmalle dubbel' is my favorite Belgian beer, I can PM you my address

I was wondering if I could add a xr-e to the comparison, but due to the collor difference, that would not have been meaningfull. It would only give an idea of the size of the spot, not the intensity.

Johan

 

[znomit]

I connected 2 red XPG's

Red XP-G?

 

[Packhorse]

I must admit that is not the result I would have expected at all!

 

[wquiles]

I connected 2 red XPG's (since I only have red ones at the moment) to the same driver in parallel, providing 1040mA, so both LEDs should get about 500mA.

I am not trying to pick on your excellent progress, but no, that is not correct. If you have two LED's in parallel they almost never would get the same current. Current through LED's in parallel depends entirely on the VF of each LED, and it is "very" rare to have LED's with the same identical VF. If one VF is higher than the other, that LED will get a higher current.

If you want to make sure both have the same current, you:
- measure the VF and match LED's with the "same" VF, then if you wire them in parallel the current through each one will be approximately the same

or

- wire the LED's in series - the only way to guarantee the current is the same in both LED's.

Will

 

[jspeybro]

I am not trying to pick on your excellent progress, but no, that is not correct. If you have two LED's in parallel they almost never would get the same current. Current through LED's in parallel depends entirely on the VF of each LED, and it is "very" rare to have LED's with the same identical VF. If one VF is higher than the other, that LED will get a higher current.

If you want to make sure both have the same current, you:
- measure the VF and match LED's with the "same" VF, then if you wire them in parallel the current through each one will be approximately the same

or

- wire the LED's in series - the only way to guarantee the current is the same in both LED's.

Will

yep, you're right. thought about wireing the leds in series after I did the test, but since I wasn't sure the driver could handle this I didn't bother trying (and didn't have time). I'll check the Vf's of these leds to see if they more or less match.
There's indeed a chance that the output is the same due to different Vf. I'll see if I can get it right in the weekend.