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Is orca reflective film just thicker tyvek?

HuckFinn

New Member
I've been wanting to replace my panda film with something better since I bought it, and I'm looking at foylar and orca. I cant seem to find foylar locally but at least one of my local shops carry orca and when I seen it in person I instantly recognised it as tyvek house wrap. The only difference that I noticed was the thickness and the absence of the word tyvek in huge print on one side. So maybe someone who is more in the know could tell me if there is a significant difference?
 

Franknstrain

New Member
Well since tyvek is more a moisture barrier. With little to no reflective values.
Personally IMHO I would not suggest using tyvek. I would stick with what works.
 

HuckFinn

New Member
Well since tyvek is more a moisture barrier. With little to no reflective values.
Personally IMHO I would not suggest using tyvek. I would stick with what works.

little or no reflective values, your very mistaken. ive found a couple of university studies stating otherwise .


"Measurements of TYVEK Reflective
Properties for the Pierre Auger Project"
http://www.phy.olemiss.edu/HEP/docs/JustusThesis.pdf

heres a quick mention from the SAO/NASA ADS Physics Abstract Service
"A study on the reflectivity of Tyvek"
Tyvek is a permeable, strong, white material made by Dupont. Due to its high reflectivity, many physics experiments use Tyvek to increase the collection of light. The Super-Kamiokande neutrino experiment in Japan uses this material extensively in its outer detector and its reflective properties are part of the Super-K Geant3 Monte Carlo simulation.

and i found this interesting looking paper that i havent had time to read completely on the university of michigan web site
www.ifm.umich.mx/~arteaga/Publicaciones/NIM2005_tyvek.pdf
 

HuckFinn

New Member
and what i like most about tyvek is that it reflects with very little shift to the spectrum, unlike panda film. i'll take a look and see if i can find that reference chart to pandas spectrum shift. I've slept since then and cant seem to find it at the moment.

also ppl claim that panda is 92% reflective (or whatever) but I've never seen and couldn't find any real data on that. if someone could help me out there it would also be appreciated
 

Franknstrain

New Member
little or no reflective values, your very mistaken. ive found a couple of university studies stating otherwise .


"Measurements of TYVEK Reflective
Properties for the Pierre Auger Project"
http://www.phy.olemiss.edu/HEP/docs/JustusThesis.pdf

heres a quick mention from the SAO/NASA ADS Physics Abstract Service
"A study on the reflectivity of Tyvek"


and i found this interesting looking paper that i havent had time to read completely on the university of michigan web site
www.ifm.umich.mx/~arteaga/Publicaciones/NIM2005_tyvek.pdf

My Bad!! I stand corrected, Thank you for those links. :peace2: :goodjob:
 

Franknstrain

New Member
and what i like most about tyvek is that it reflects with very little shift to the spectrum, unlike panda film. i'll take a look and see if i can find that reference chart to pandas spectrum shift. I've slept since then and cant seem to find it at the moment.

also ppl claim that panda is 92% reflective (or whatever) but I've never seen and couldn't find any real data on that. if someone could help me out there it would also be appreciated

I dont know about 92%. I use panda. I even ended up having to replace it after a year or so because it started to get brittle in spots. So now I am considering mylar over the new panda. I havent bought tyvek in ages so I am not sure on the cost if its comparable to panda. I started to think about when I was building homes using tyvek as a moisture barrier.. then remembered how hot it was when you stood in front of the wall when the sun was beating down. You could burn or tan if you stood there long enough. So maybe that may be something to think about also? :peace2:
 

HuckFinn

New Member
the only down side i can find with the stuff is that it doesnt totally block out light, about the same pass through as standard 4mil mylar. so it may not be the best material for a flowering tent. but im betting it will be an extremely fast and easy way to cover entire walls, like my basement :thumb:
 

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
I've often wondered when light-reflectivity percentages were quoted for thin materials, are those percentages of the gross light that hits them or percentages of the amount of light that doesn't pass right through?
 

Pross

New Member
can anyone give me the technical name of the orca paper? Since it seems I'm having a time finding it online. Same thing happened when I tried to find panda paper. Typed in black and white poly and Boom! A million and one sites to order from. edit: never mind I found. Official name is: Orca Grow Film
 
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TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
Not sure. It'd have to be pretty thick Tyvek to block all light transmission (although the Orca product is pretty thick at 11mil). My gut tells me that it's not, because as far as I know DuPont still holds exclusivity on Tyvek® and they tend to get pretty extreme when others try manufacturing/selling their products. But I could easily be wrong.

According to Orca's website (linked in post #10), Orca film has a very flat reflectivity profile across the visible spectrum. From a quick read-through of the .PDF linked in post #3 (thanks to HuckFinn for that), it appears that although Tyvek is reflective, it does not have that flat profile (and a flat profile is what we want, along with spectral stability (IOW, wavelengths do not shift) and actual optimum gross reflectivity numbers). Although the study only used a very limited number of samples so there was the possibility of large statistical errors; however, the samples tested did have the same trend within the sample group <SHRUGS>. I'll have to give it a more thorough reread when I've got my maths hat on.

Going strictly off of Orcas's website (admittedly, a bad idea), their product looks like a very good one in comparison to the other readily-available products we routinely consider. And some of their supporting text/graph materials kind of supports what I've always felt about brilliantly white flat paint being an excellent material for the GR walls. That suggests (to me) that there is something to their arguments, perhaps more than what could be expected from a typical marketing department, lol; not because they agree with my thoughts, lol, but because logic suggests that it would be the case. (BtW, they do NOT list bright flat white paint in their Reflectance versus Wavelength chart. Perhaps because that and their product might be close enough in characteristics - if not in absolute gross reflectivity - that many might simply choose to prep/prime/paint their walls instead of purchasing their products, lol. But that is purely speculation on my part and should NOT be taken as anything else.)

I saw on the Orca website that they were at the Indoor Gardening Expo in San Francisco this weekend. Did anyone attend and visit their display? It also shows that they will be at the Long Beach Expo on October 22-23. Anyone who is interested in their product should (if possible) visit, ask for a sample, and inquire in person.
 

LEDBud

Well-Known Member
(old thread gets reborn)


I was planing on using tin foil ( to block light and be reflective ) then I found a partial role of black and white Tyvek so installed it as a first layer , the tin foil never went up before the 300w LED did which is when I noticed the thin black and white Tyvek was blocking the light , only a slight glow was visible , a 2nd layer over the door section blocked it completely.
After some investigating today I learned that Tyvek has a 98% reflectivity score , as a bonus it breaths which will keep mildew away.
 
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