FM34 Beam Diffuser

Sig Sauer

Newly Enlightened
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Jul 2, 2008
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Is there anyone who have pictures of the beam with a FM34 Beam Diffuser on? I'm interested to see how different the beam would be with the FM34 mounted.
 
Sig Sauer:

I'm very happy with my FM34. :twothumbs

http://www.cpfmarketplace.com/mp/showpost.php?p=2171547&postcount=177

The FM34 much more effective than using diffusing film (Write Right) or 3M satin tape. Both of those methods will smooth the beam out by scattering light - with the result being a slightly dimmer light. The FM34 seems to directionally diffuse the beam; producing a sofly rounded, bright blob of light - without appreciable loss in overall light. It's a very nice effect.

Please be apprised of the mounting tolerance. The unit is described as 1.25". My Cabelas XPG diameter measured at 1.262" and was a very tight fit, so I'd guess the tolerance is something like +.01".

Of course, if you are smaller than that, you could build up the circumference with tape or other material.

If the head diameter is larger than that, I wouldn't try fitting the FM34 on it. You'll run a high risk of either damaging the FM34 or damaging your flashlight when you crank down the locking mechanism. A great deal of pressure is exerted by the cam mechanism.
 
Sig Sauer:

I'm very happy with my FM34. :twothumbs

http://www.cpfmarketplace.com/mp/showpost.php?p=2171547&postcount=177

The FM34 much more effective than using diffusing film (Write Right) or 3M satin tape. Both of those methods will smooth the beam out by scattering light - with the result being a slightly dimmer light. The FM34 seems to directionally diffuse the beam; producing a sofly rounded, bright blob of light - without appreciable loss in overall light. It's a very nice effect.

Please be apprised of the mounting tolerance. The unit is described as 1.25". My Cabelas XPG diameter measured at 1.262" and was a very tight fit, so I'd guess the tolerance is something like +.01".

Of course, if you are smaller than that, you could build up the circumference with tape or other material.

If the head diameter is larger than that, I wouldn't try fitting the FM34 on it. You'll run a high risk of either damaging the FM34 or damaging your flashlight when you crank down the locking mechanism. A great deal of pressure is exerted by the cam mechanism.

Thanks for the info. Looks good!

Does your beam get more flood or does it just dim the light?
 
Sig Sauer:

It depends on what you're looking at. If you're looking at the hotspot, the FM34 is definitely less bright. If you're looking at the total output (i.e., including spill), the effect is that the light is not dimmed.

In fact, the overall light output is reduced because the frame of the FM34 blocks some of the light. However, the loss is at the edges. So, the effect is negligible.

A couple of practical examples:

My Cabelas XPG Q5-mod, when looking at an object 200 feet away looks much dimmer, because the FM34 diffuses the light so much. I'm not "looking at the hotspot" per se, but the center spot is the greatest contributor to throw, so it is, in effect, the same thing.

Whereas looking at the walkway 20 feet in front of me, the FM34 provides a wall of light that is effectively brighter than what would otherwise have been lit up by the Q5's spill.

So, the answer depends on what you using it for.

==============================================

P.S. Contrast that with using satin tape or a diffusing film. Both of those alternatives will result in a dimmer hotspot and dimmer sidespill. And since our pupils tend to react to the brightest source of light, the hotspot tends to reduce the effectiveness of the spill even further. So subjectively, the tape or diffusing film seems darker than the FM34, even though a lightbox test might show them as having comparable outputs.

.
 
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Does your beam get more flood or does it just dim the light?


There is always some loss with any type of diffuser. I recall someone performing an unscientific light box test where there was roughly a 20% loss from the Surefire ... F04, I think it was..
 
Here's my C3 w/M60W, and a few wall shots. (wall is not white, it's more light beige)

P1010100.jpg

P1010102.jpg

P1010101.jpg

P1010103.jpg

diffuser OFF
P1010106.jpg

diffuser ON
P1010105.jpg
 
Those are great shots Brighter. I have FM34 diffusers on my Malkoff equipped 6P & G2 and F04 diffusers on my E1L, E2D & mini magled. I feel its the best of both worlds (throw and flood) at the flip of a switch. The G2-FM34-Malkoff is my go to light. Any reduction in light is overshadowed by the feeling of having two lights in one.

-JB
 
Same setup as brighterisbetter's, except on a 6P instead of a C3-HA.
I love the M60WF and M60WLF, but think the M60W/FM34 is even better. It loses on brightness, a tiny bit dimmer at beam center than the WLF, and noticeably dimmer than the WF, but has a wider beam than they do.
I think I already said it somewhere else, but my other lights hardly even seem usable compared to the Malkoff warm flood models, and the diffused M60W.
dscn3721.jpg
dscn3723.jpg

Above and below: M60W on the left, M60W/FM34 on the right.
dscn3730.jpg
dscn3731.jpg

Notice the foreground on the second shot, and the gutter on the side of the house. Both beams were centered on the front door from maybe 30ft. away. The right side got partially blocked by the tripod the camera was on.
 
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Here it is between the Malkoff warm flood models.
M60WLF, M60W/FM34, M60WF
dscn3724.jpg
dscn3723.jpg
dscn3725.jpg
 
dscn3721.jpg
dscn3723.jpg

dscn3730.jpg
dscn3731.jpg

Notice the foreground on the second shot, and the gutter on the side of the house. Both beams were centered on the front door from maybe 30ft. away. The right side got partially blocked by the tripod the camera was on.

I am suck a dork I thought that was the moon over your house at first and wondered how the hell it diffused.:shakehead
 
I see what you mean. I forgot to put any kind of caption telling what they were, too.
Fixed it:)
 
The FM-34 is a big thing to add to the front of a light compared to the F04. Does anyone make something like an F04 for 1.25" bezels? I know that I could use 4 or 5.
 
The FM-34 is a big thing to add to the front of a light compared to the F04. Does anyone make something like an F04 for 1.25" bezels? I know that I could use 4 or 5.
Surefire's older style beamcovers/shapers were much more slender and lacked the locking cam lever, though they still have a prominent hinge and a tab for opening. Someone correct me if I'm wrong, but you basically take the 'M' out of the part # to find the older style. For example, instead of FM35 for the red filter, it'd just be F35. I'm not sure if they had an older style diffuser though, it would be a p/n F34 if so. If I'm incorrect, please correct me. :duh2:
 
It's a little different. Look here:
http://www.lpstactical.com/accessories.htm
I don't know if they actually have all those in stock any more, but it's a good reference tool since the tip-up filters aren't on SF's site any more.
Oh gotcha, so based on that site, it's the F '2x' series that fit the C-series bezels and not the F '3x' series, cool thanks for the link.
 
Surefire's older style beamcovers/shapers were much more slender and lacked the locking cam lever, though they still have a prominent hinge and a tab for opening. Someone correct me if I'm wrong, but you basically take the 'M' out of the part # to find the older style. For example, instead of FM35 for the red filter, it'd just be F35. I'm not sure if they had an older style diffuser though, it would be a p/n F34 if so. If I'm incorrect, please correct me. :duh2:
I'm afraid it's not that's straight forward.
The Classic version of the FM35 was the F26.

Here's a quick guide to SureFire's BeamFilters...

FMx3 IR BeamFilters - Glass (I'm not sure of it's details)
FMx4 Beam Diffusers - POC's 'LSD holographic 20deg diffusion polycarbonate
FMx5 Red BeamFilters - Multi-AR coated tempered glass
FMx6 Blue BeamFilters - Multi-AR coated tempered glass
FMx7 BeamCovers - Hard Anodised aluminium alloy

FM1x (1.62" diameter) - "M3" Millennium Bezel, 9N, 9AN & KL6.
FM2x (2.5" diameter) - Millennium TurboHead bezel & 'KT' TurboHeads.
FM3x (1.25" diameter) - Standard "6P" bezel (tight on the G2/G3/G2Z).
FM4x (1.36" diameter) - Z32 aka Classic WeaponLight Shock Isolated Bezel.
FM5x (1" diameter) - ScoutLight, E-Series bezels etc
FM6x (1.47" diameter) - M2, 8X, 8AX/8NX/L7, KL3/KL5/U2 etc

FM7x for HellFighter (FM73 IR), (FM77 Amber*) & (FM78 Opaque*)
(* It would make sense if these were the other way around, but it appear not)

Classic BeamFilters for Taclight (Z32) (1.36" diameter)
F11 - Red
F12 - IR
F13 - Cover
F19 - Blue
F63 - BeamShaper (Medium)
F64 - BeamShaper (Wide)

Classic BeamFilters for 8-Series (& "M2") (1.47" diameter)
F62 - Cover
F66 - Red
F67 - Blue
F68 - Traffic Wand
F69 - IR
F70 - BeamShaper

Classic BeamFilters for 9-Series (& "M3") (1.62" diameter)
F32 - Cover
F33 - BeamShaper (Medium)
F34 - BeamShaper (Wide)
F36 - Red
F37 - Blue
F38 - Traffic Wand
F39 - IR

Classic BeamFilters for standard bezel ("6P") (1.25" diameter)
F16 - IR
F17 - Cover
F23 - BeamShaper (Medium)
F24 - BeamShaper (Wide)
F26 - Red
F27 - Blue
F28 - Traffic Wand

Classic BeamFilters for T-Series Extended Range TurboHeads (3" diameter)
F40 - BeamShaper
F46 - Red
F47 - Blue
F49 - IR

I'm sorry for it not being very comprehensive. Its difficult to remember everything....

Al
 
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