Mirror = good or bad

Just fucking around with the box and thought of using mirrors to direct my led's light into those tight spots, has anyone tried this. I just put this 5 inch round mirror in (on the right) it is directed at those two larger ones I can see a clear difference with it there and not myself but don't know what the plants will think of it

No. Get some wrapping paper from the dollar store (the kind with the reflective backing) or mylar blankets.

Mirrors are bad as they do not reflect properly and actually absorb a lot of light.

Glass absorbs light. Get reflective film.

Mylar emergency blankets let a lot of light pass through. I would not recommend it.

Dam what a shame, imagine full mirrored boxes that would be awesome

I don't know about where you live,but locally in BC I pay about 27-30$ for 4ftX50ft of Mylar.
is 95% reflective

Ebay has panda film for fairly cheap.

Pop The Trunk said:

Ebay has panda film for fairly cheap.

Click to expand...

That stuff works good,most hydro stores have 50-100ft rolls for a reasonable price.
the panda film is was cheaper than Mylar just less reflective.

But Mylar can be scratched easily(loosing reflection)
its all a matter of personal choice

I have a 30w cfl on a lead that I am going to stick in there then I think

I still don't see why a well-placed mirror would hurt anything. As far as I can tell, since the light is being reflected back to the plant, there is no loss, only gain. If you were transmitting the light through a piece of glass, I would avoid that because there will be some absorption. However, that is not the case with a supplemental mirror as you were going to let the light get absorbed by the floors, walls, dirt, and pots anyway. Mylar is clear like glass, so in the end you still have a metallic coating on a clear material to make it reflective, same as with a mirror. Glass is is a much better insulator than than mylar film, but unless you're lining the entire room with mirrors, it shouldn't matter much. That's my two cents.

A mirror is a reflective coated piece of glass with a black backing. So the light has to go through the glass to hit the reflective part, then go back again to reach the plant. That is why mirrors don't work good even though our eyes may seem to tell us otherwise.

That is a coating over the silver to keep it from being easily scratched off, the light is reflected by the silver coating and it never 'sees' the black side. It is the same silver that coats the mylar film...so I still don't see any real reason that a mirror would hurt anything. However, in a room filled with light, it will inevitably find it's way to the back of the mirror where it could be absorbed to heat it up, I suppose. But, if the mirror is up against the wall, that won't matter either... are there any other reasons? because mylar is basically a mirror with polymer instead of glass as a clear substrate upon which to deposit silver.

From memory: Household mirrors reflect somewhere between 40 to 60% light.
Problem is that the reflective layer sits behind a layer of glass. Not only is the glass not 100% clear, but the light reflected off the reflective layer is somewhat reflected by the glass as well - thereby sending it back towards the reflective layer again.

Mylar is thin PET film with a metal-oxide on top. This means that the reflective layer is the first and only layer that the light hits.

Yes, the black coating on the back is simply to keep it from being scratched, but the light has to go through the glass to reach the silver coating, then bounce back through the glass. It is that process of having to go through the glass twice that reduces its reflectivity.

No one is saying not to use one, it is better than nothing, but other methods work better than a mirror if you want to try to reflect as much light as possible to the plants.

I see that common glass and mylar can have similar refractive indices, so the benefit must come from its thin film property, but this causes flexibility and a more diffuse reflection, so it's a give and take.

edit: CaliJoe basically said what I'm saying here, but he said it while I was typing this^^ lol

mc130p

Mirror:
Light--->|Glass|--->|Reflective Silver|

Reflective Mylar:
Light--->|Reflective Aluminum||Mylar|

See? Light does not pass through the Mylar! The Mylar is a protective backing much like the black coating on the mirror. You can actually scratch the Aluminum off with a sponge and some abrasive cleaner (Brasso, or something) if you're scrubbing the right side. Which leads me to my next point. Be sure to install reflective Mylar with the shiny side out! Both sides are shiny, yet one side is shinier, and you can tell which side is which with the naked eye.

Is a mirror bad if it's all you have? Not really, it is better than nothing. Yet, reflective film is so cheap, instead of being innovative, try innovating yourself to $10-$20 to buy some reflective film, imo.

Mirrors OWN in specular reflection.
White ownes as a diffuser / Lambert scatterer.
Both


When angled right nothing compares to amount of photons mirrors will reflect @ your plants.
Even with a 10 -15 % loss for green tint an refraction.
A good example of this is signal mirrors .
or when you get super burnt when swimming.
I used mirror for yrs.

Its free light just, angle mirrors an put light to your plants