Auto window tint claims/performance question

[randomwalk101]

I just got my 2023 Tesla front windshield and front windows tinted with Xpel XR Plus nano-ceramic (70% windshield and 35% front windows). 

 

Based an Xpel claims of 96% IR rejection

 

XPEL-PRIME-Spec-Sheet-USA-V2-1.pdf

 

I used a Solar Power Meter that measure the infrared/heat. I made some measurements and I was suprised of the results.  It appears that it's FAR from 96% IR rejection as claimed.  Please note this is full sun (no glass) vs glass AND tint.   I should have done the glass only but too late (tint already applied).  I'll try to find a non-tinted car to take the measurements in the future...

Car: 2023 Model Y
Tint type: Xpel XR plus nano-ceramic

Front windshield: 70%
Front windows: 35%
Rear windows: no tint (factory colored)
Rear hatch: no tint (factory colored)


Car parked @ full sun

Readings:
Meter pointed at the sun (no obstruction): 797
Front Windshield: 56
Front window: 179
Rear window: 94
Rear hatch glass (lifted up): 66

I forgot to do the roof glass. I'll retake all the measurements again for consistency when I do the roof. But looking at the factory color tint, it's appears that it's blocking out the heat better than the nano-ceramic? I'm surprised by this. I was told that the "dye" or darkness in the nano-ceramic tint doesn't make much of a difference.

[LeadfootCJ7]

Good info.  'Im interested to see where this leads.  How does it feel with the tint compared to before?  Does it feel like it makes a significant difference?

[Ryker]

Unless you have a really high dollar meter you aren't measuring any thing worthwhile. 

 

It's also likely that the "96%" or whatever is a narrow band of IR..... 

[randomwalk101]

This is what I have

https://www.edtm.com/index.php/sp1080-digital-solar-power-meter

 

We are measuring the relative difference so absolute number doesn't make much of a difference 

 

 

[Tintguy1980]

Sorry Randomwalk101, but a BTU meter was specifically designed to measure performance of HVAC units, therefore is unreliable in measuring the sun's electromagnetic radiation.

 

As it has been stated by Ryker: "Unless you have a really high dollar meter you aren't measuring any thing worthwhile." The film manufacturers rely on a $100K+ spectrophotometer to conclude solar performance of window films. If you want the best in accuracy during field testing you'll pay a hefty price for one the the following hand-held devices. https://www.edtm.com/

Here's an explanation from a previous thread that may shine some (solar) light on your quandary:

 

~ The chart attached shows electromagnetic radiation range in terms of Visible 48+%, Ultraviolet <2%, and Near infrared (NIR) 49+/-% light (using the red line). Publishing one wavelength/nanometer number really does not give the big picture.

 

Let's compare 3M's published single wavelength in NIR is at 950nm (nanometers) to Xpel's at 1025nm: you will see by the linear charting that there's a pronounced dip (bottoming out) at 950 and a peak at the 1025 position.

 

The peaks and valleys are representative of the 'intensity' of the NIR radiation. A dip is low intensity, a peak is high intensity. Neither of these two numbers fall within the most intense NIR radiation found between the 780 and 1000nm range. So, if someone were to publish an 800nm range (a high peak in intensity), it stands to reason 800 will be a better published performance number to that of 950 or 1025.

 

That said, the entire NIR range (considered to be 780-2500nm) is already accounted for in each films' published TSER (including visible and UV light radiation).

 

Hopefully this should point out the 'why' it's not reliable to state a single wavelength as any films' performance capability.

 

Edit for the sake of Joe Public reading this: the entire electromagnetic radiation range of the sun (UV, NIR, Visible light) is responsible for 'heat', however, only after it strikes, is absorbed by a surface and is re-radiate off that surface as far-infrared (FIR). FIR IS known as heat.

The reason behind any use of NIR wavelength(s) is because the human body senses NIR conversion to FIR much quicker than UV or Visible light energy. NIR travels beneath the skin closer to nerve endings, which is where water, being highly absorptive of NIR, heats up.
 

Now, if a reported 88% NIR rejection at 1025nm is brought into perspective by using NIR's 49% of 100% of the sun's radiation, in reality it's such a minuscule number when accounting all wavelengths from the sun, combined. Sure sounds good to say 88%, but the (TSER) big picture tells the truth in film performance values. And, it makes stating 88% heat rejection misleading at best. ~

[Ryker]

20 hours ago, randomwalk101 said:

This is what I have

https://www.edtm.com/index.php/sp1080-digital-solar-power-meter

 

We are measuring the relative difference so absolute number doesn't make much of a difference 

 

 

So you aren't measuring IR but a generic "solar heat". I've got the old analog btu meter and it was a cool tool but I don't use it and have not for probably 20 years. 

 

You are way overthinking this.  

[randomwalk101]

Thank you for the explanation gentlemen. I definitely learned something new today. 

 

As a average consumer, say you pay for a specific type/brand of tint but after you get the car back, how does one knows that tint on the car is what you asked for?  Thank you again. 

[Ryker]

4 hours ago, randomwalk101 said:

Thank you for the explanation gentlemen. I definitely learned something new today. 

 

As a average consumer, say you pay for a specific type/brand of tint but after you get the car back, how does one knows that tint on the car is what you asked for?  Thank you again. 

You don't.  You trust the shop or you don't. 

 

Do you question everything like this?  Did I get an Angus steak?  Was it US or Mexico?  Was it really an 8 oz or was it 7.8 oz? 

[Tintguy1980]

15 hours ago, randomwalk101 said:

 how does one knows that tint on the car is what you asked for?  Thank you again. 

Most shops will provide you with a receipt and or a typed warranty that would/should include the manufacturing lot number(s) of the boxed roll of film installed on your vehicle. You could then call whatever number the warranty might list, communicate via snail- or e-mail, and ask your question using the lot number(s) you were provided.

 

Last time I was active in the industry 3M, LLumar, and possibly one or two others ID'd their brand with a printed logo. 3M's was on the film surface and could be cleaned away with Iso-alcohol and LLumar's would be found on the removable liner used to protect the adhesive until installed. Even still, you wouldn't know what flavor they installed be seeing the printed logo; ceramic, dye-metal or straight-dyed.

 

Lot (production) numbers ID the film. These numbers need be provided to the consumer at PoP; it is the way the film 'maker' on any warranty provided can honor a warranty.

 

 

[DynamicATL]

As @Ryker said, it is all about trust. There is no way to know for sure what film you received and nothing you can buy that will be as accurate as the film manufacturers. The closest tool is the one below but why spend $1000?

 

https://www.xpel.com/solar-spectrum-meter

 

Xpel XR Plus is measured at a singular wavelength (1025nm), over the whole spectrum it is lower. Does that make it a bad film or one that does not block a good amount of heat, absolutely not.