Daytime Privacy Film - is ext reflectance the right measurement?

[PenguinTint]

I'm looking at films for daytime privacy and trying to better understand all the spec sheets and numbers.

 

If you want daytime privacy should I be looking at ext reflectance numbers and is higher better to provide more privacy? Or is that misleading? I know you can have frosted film/glass which has low reflectivity and provide privacy but staying within DR films is it higher ext reflectance better for determining daytime privacy?

 

I also noticed that the interior and exterior reflectance are somewhat correlated so for films that have higher exterior reflectance they also have higher interior reflectance. From what I understand for interior reflectance you want as low reflectivity as possible so you can see out at night.

 

So seems it's a trade-off right? If I want greater daytime privacy which requires a good level of exterior reflectance then I'll likely sacrifice nightime viewing due to a higher interior reflectance. Is that how it works?

 

So specific films I'm looking at are Slate 30 vs Fusion 28.

 

For double-pane 1/8":

- Slate 30 is ext refl of 29% and int refl of 15% with VLT of 28% and glare reduction of 66% TSER 53

- F28 is ext refl of 37% and int refl of 21% with VLT of 24% and glare reduction of 70% TSER 57

 

From these numbers is it correct to conclude that:

1) In general F28 will appear more shiny due to the higher reflectance then Slate 30?

2) F28 will provide more daytime privacy due to the higher ext reflectance of 37% vs 29%?

3) On the flipside will F28 be harder to see out at night since the int reflectance is higher 21% vs 15%?

4) For decent daytime privacy is there any guideline? Where I need to look for a min ext reflectance of 25%+?

5) Or is it more nuance than just looking at the numbers?

 

I'm working to try to actually get samples installed on windows so I can do a visual comparison as numbers will only tell part of the story but I wanted to just understand what the numbers can and cannot tell me.

 

Thanks so much!

Edited November 7, 2017 by PenguinTint

[Roach]

13 hours ago, PenguinTint said:

From these numbers is it correct to conclude that:

 

Yes, you are correct in your conclusions. The higher the ext. reflectance, the harder it will be to see in during the daytime.

 

As you said, everything is a trade-off. So it all comes down to what you are willing to give up in order to get.

 

Is there a min you wanna try and be at? I would say at least ~30%.  That's just based on the films I offer - which do not include the ones you have been looking at. I've never seen those films in person, so I can't speak towards which would be better aside from going off the stated specs.

 

 

[DynamicATL]

My question is why more than one thread covering the same topic?  Stick to the other thread as it has more information.