Strange difference between Surefires

[recercare]

I visited pk-engineering's picture gallery and compared beam shots.

This may seem weird, but I thought the M2 with P61 lamp looked brighter than G2 with the same lamp.

The M2 with P61 lamp looked much brighter than the 8NX/AX as well, which is odd considering the modest 10 lumen difference. Judging from pictures the 8NX's brightness was somewhere between P60 and P61....that means 80-90 lumens.

After some serious thinking I believed the answer to be difference in beam angle. I looked at 8NX picture again only to discover that the beam did NOT cover more area than the P61, and looked much dimmer as well.

Any comments on this?

 

[Size15's]

It could be that the light from the M2 bezel is shining through AR coated Pyrex that allows more light through then Lexan.

It could be that the Lamp Module is deeper in the M2 Bezel compared to the standard SureFire Bezel so the beam is slightly smaller overall and therefore slightly more intense.

The light intensity distribution is different for many lamps - the X80 has a larger reflector, produces a less intense, but larger main beam with a narrow intense spot in the centre. The P61 in my experience is a big round main beam of perfect intense light, and I've noted that the beams look different in the M2 Bezel - the edge of the beam is more defined.

Al

 

[**DONOTDELETE**]

M2 is Pyrex and G2 is Lexan. 13703 Pyrex bezel is a lot "whiter" than 13703 Lexan(M3T,M4,M6)

 

[Size15's]

I've directly compared the N2, MN15 & MN16 in Lexan & Pyrex M3Ts

Also, I've compared all these lamps in the M3Ts to the Classic 3" TurboHead running the same lamps.

I have compared the P61s in Lexan & Pyrex M2 Bezels, and noticed a difference - infact, I was able to tell them apart when my mate shone the beams side-by-side.

The Pyrex is brighter.

Al

 

[Lonewolf]

Maybe this will help.
http://www.pk-engineering.com/spec/ge-lexan.html

And
http://www.pk-engineering.com/spec/pyrex-ar.html

These posts tell you how much light each material lets pass.

 

[Bucky]

Yet another great reason to have pyrex lenses in as many SureFires as possible

.

Bucky

 

[SurefireM6]

And let's not forget Lumens does not tell you how bright or white the light is. It is possible that a 60lm light be whiter than a 110lm light.

Pyrex makes a very noticable difference, the 8AX is brighter than my 8NX. My M2 brighter than my 6P, etc. Isn't there something like a 10% difference in light transparency between Lexan and Pyrex?

 

[txwest]

I don't find that to be true with my lights. I don't find a noticeable difference between my D2 & my M2 with the same lamps & fresh batteries. TX
EDIT: Just compared them again. Maybe a slight difference, but not enough to get realy excited about.

 

[brightnorm]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Size15s:

The Pyrex is brighter.
Al

<HR></BLOCKQUOTE>

The best, and perhaps only way to tell definitively is through repeated "equalized" (same lamps with same # of hours, same brand and fresh, voltage-tested batteries, same exact distance and position from screen/objective, etc, etc) DOUBLE BLIND tests, preferably with three or more "judges".

Brightnorm


.

 

[Lonewolf]

I will judge if I get to take one of the lights home.