Claudiusx":2hn6giy3 said:Hi Ben,
The easiest way to know would be to have a solarmeter, but with some math and measurements you can find out how much your mesh blocks realitvely accurately. You can find out exactly, but the math is a bit trickier, so this method gives you a close estimate.
You just need to know the gauge of the wire/mesh, or you need to be able to measure the width of the wire/mesh strand with an accurate caliper. From there, you can just count the number of meshes in a sq inch, add up the space taken up by the number of meshes, and use that number to subtract from the area of a square inch to figure how much is being blocked.
The reason this isn't as accurate a method as another more complicated method, is because this method doesn't account for the overlap of wire/mesh crossing over eachother in it's grid like pattern. Still, it would be close enough for this case. Any discrepancy would lead to a difference in percentage of less than half an inch when it comes to figuring your distance.
-Brandon
Claudiusx":v4mms26m said:Well, your lid might not be more tricky actually. If you can accurately measure the diameter of the circle cutouts, you can get the area of the circles. Then you do the same thing, take the surface area of 1 square inch, and then subtract from that, the area taken up by the number of circles and half circles in the square inch.
-Brandon
Claudiusx":3ab5vcps said:Ben, that's the beauty of the internet huh? A calculator for everything lol.
Since you're working with such small measurments, you really need to make certain that your measurements are acurate.
For instance, if you're off 1mm on your hole size (D), the difference goes from:
32% open at 3mm
to
58.2% open at 4mm.
Or, lets say you're off 1mm on your pitch. If you are, that's also still 50% open. If you're off on pitch and hole size by a mm, your open area could be 90%!
So it would be best really to have calipers that measure smaller than a mm, that way you could find out if your pitch is 5, or if its 4.5.
You're working with such small numbers here, the difference half a MM makes is huge.
Could you post a picture of your lid?
Would it be feasible for you to cut the area directly under where the UVB would be placed? That would totally negate all this and still allow you to have a working lid to keep things out or in lol.
-Brandon
Claudiusx":1oxfw813 said:If you're building the tanks yourself, why not just build them a bit taller so you can mount the UV inside the tank and not worry about the mesh?
If you're going to custom build a screen though, I'm sure you can ask for a bigger % open? Or a slot cut open for the UV to be unobstructed?
But yes you are right, if it cuts it 50%, it needs to be twice as close.
However, I've got to wonder how that might produce shadowing and patterns of light that might not be best.
Truthfully, I'd look into any other option besides settling on placing the UV over something the blocks 50% of it. If you can't get something that is 30% or less blockage, I would find another alternative.
-Brandon
Claudiusx":1f3nn00y said:Correct, I wouldn't settle for anything higher than 30% blockage.
-Brandon