D-c-fix diffusion film

LED Flashlights – General Info
1

Since this question often comes up, let’s start a new thread on it.

The name was changed from sand to milky some time ago, but the model number stayed the same.

The correct SKU: 346-0211

Where to purchase?
Amazon
Bauhaus (Finland)
Smaller pieces from Boaz

How to install it?
It sticks pretty well on an even glass lens surface. Best position is to place it between the lens and bezel for secure fit.

What is it good for?
Protects the lens (if inserted on the outside)
Makes a throwy light floody
Evens out an uneven tint (Cree rainbow)

Before (with a noticeable tint shift, green ring around the hotspot)

After (also a minus green filter added to reduce overall greeniness)

How much does it reduce output?
5-10%

Does it affect tint?
It evens out the tint throughout the beam so yes, the hotspot will probably be different if you used it on a light with a horrible emitter.

Does it affect CRI
No

Without d-c-fix

With d-c-fix

2

Boaz has DC-Fix for sale as well:

https://budgetlightforum.com/t/-/35838

3

This stuff is fantastic. I’ve used it on a lot of lights, and it turns the ugliest beam into a work of art.

4

Just bought 2 meters roll :slight_smile:

5

Thanks maukka for doing the testing for us. Now, could someone make those before and after CRI test charts into a mouse-over so that the miniscule differences can be seen quickly?

6

Thanks for testing, Maukka.
Only 5 - 10% loss in output is better than i thought it would be.

7

A test with everything you could possibly want to know about using dc-fix on your flashlight
Great test! :+1:

8

Thanks for taking the time to do this. It’s good to have this sort of information documented.

Long term, it might be nice to have this kind of information indexed somewhere for easier access than sorting through forum threads.

Also, has anyone ever done a controlled comparison of DC-Fix vs. a matte finish tape like Scotch “Magic?” I’m curious if the DC-Fix diffuses a different amount, is more durable, sticks better, etc.

9

Thanks guys. I didn’t actually do anything really, just gathered the data from some of my old scattered posts.

10

What is 803?
Also, measurements don’t look like 5-10%

11

http://shop.leefiltersusa.com/Swatch-Book-Designers-Edition-SWB.htm

For heat concerns, Lee makes a Zircon line that is heat resistant:

The 802 Zircon Minus Green reduces lumens by 25, that would be closest to the 1/2 minus Green, that reduces by 28

the following percent numbers are the amount of light transmitted, so 71.5% transmission means 28.5% lumen reduction…

Lee 248 Half minus green: 71.5%
Zircon 802: 75%

Zircon 803: 79.9%
Lee 249 -Quarter minus green : 81.5%

Zircon 804: 83.6%

Zircon 805: 86.6%
Lee 279 -Eighth minus green : 87.2%

Discussed here

Examples of with and without Lee

12

Thanks for the explanation.

13

So, output is cut ~10% but intensity is cut ~30%.

14

Those are just examples from one light. A BLF GT will probably suffer a lot more of a reduction in intensity.

15

So, a floody light will lose less intensity than a thrower? Is it a logarithmic effect?

16

I haven’t done the math or the measurements so this is just a guess, but it might just be a function of lens size. Bigger lens = more diffusion film = more diffusion.

17

Just an educated guess. If you already have a somewhat diffused light (eg small heavy OP reflector or frosted optics), naturally adding more diffusion doesn’t have the same impact as diffusing a very narrow beam (large SMO reflector).

18

That makes perfect sense. Thanks!

19

Okay, here’s a thought. It would be nice if someone would test this hypothesis. Compare a small, but throwy light (such as Convoy C8), to a larger, floodier light (such as BLF Q8), both with diffusion film. I’d love to see measured results. :wink:

20

Doesn’t sound right. It seems to me that
Bigger lens = less light hitting any spot = just like lower mode = no effect on diffusion.
Though when pattern size is large in relation to lens size that would be different.