Dark Room Louvers: Worth the money?

[pontiac]

Requesting some feedback on darkroom louvers. I understand they work well for what they're intended for (darkrooms), but how good are they for the far more light intense growroom? Will I be better off using ABS/PVC pipes or regular louvers instead?

 

[drow]

1000w will heat that baby up. If I am correct they have thermal insulation. Also depends on how big the tent is

 

[Tanuvan]

Requesting some feedback on darkroom louvers. I understand they work well for what they're intended for (darkrooms), but how good are they for the far more light intense growroom? Will I be better off using ABS/PVC pipes or regular louvers instead?

I have those exact ones. I love them. They work a lot better than PVC elbows (And much more stealthy/clean looking)

Stay away from the black aluminum circle ones. Those do not allow enough airflow.

Petemoss uses them as well...

http://www.icmag.com/ic/showthread.php?t=95049&page=1&pp=15

 

[pontiac]

I have those exact ones. I love them. They work a lot better than PVC elbows (And much more stealthy/clean looking)

Stay away from the black aluminum circle ones. Those do not allow enough airflow.

Petemoss uses them as well...

http://www.icmag.com/ic/showthread.php?t=95049&page=1&pp=15

Damn, I was about to order those little black circular ones... I kinda prefer the circular-type louvers because they're easier to install (4 inch hole saw and you're done) and looks neater too.

What if i were to use 2 or 3 of them, would they still not allow enough airflow?

 

[messn'n'gommin']

Just installed my third one. Mostly because it is so easy to do. Cut a hole to fit in the wall inside my closet, screw it to plastic wall anchors, and, as an added measure, aluminum tape around the edges. Then I cut a corresponding hole on the outside of the wall and cover that with a thin A/C filter (optional) cut to fit inside a return air grill.

With the baffling system (several layers) and the exacting standards of photographers I don't think any light gets through.

However, the down side is that it restricts air flow considerably. I am guesstimating here, but I think it is somewhere in the neighborhood of 33%-50% of the 64 sq inches. lol...Hence the need for a third one with 500w's and a Stanley Blower and 6" exhaust.

Namaste, mess

 

[Tanuvan]

Stay away from the circle ones...not only are they inefficient for the type of ventilation we use...they are also not completely light proof. The slits on the circular type will let light out at a 10-15 deg angle. I had a problem with light bleeding over in an NGB style box. It takes tons of them to get any appreciable air flow.

As for the square holes, I drilled 4 holes of the square, then used a Jig Saw I picked up from the local hardware store ($35 Black & Decker 5.0 Amp Variable Speed Orbital Jigsaw)..and had the holes cut within 3-4 minutes. Easy as pie. No light leaks at all.

 

[Tanuvan]

Reduced airflow is to be expected from any type of louver.

I tested the number of them that I needed by getting a large cardboard box and at one end attach a duct fan with ducting...then seal the box as best you can with packing tape. Add as many louvers as you need around the sides of the box to prevent the box from sucking in.

I hope that makes sense. Not scientific, but gets the job done without cutting unnecessary holes in your wood.

 

[messn'n'gommin']

Stay away from the circle ones...not only are they inefficient for the type of ventilation we use...they are also not completely light proof. The slits on the circular type will let light out at a 10-15 deg angle. I had a problem with light bleeding over in an NGB style box. It takes tons of them to get any appreciable air flow.

As for the square holes, I drilled 4 holes of the square, then used a Jig Saw I picked up from the local hardware store ($35 Black & Decker 5.0 Amp Variable Speed Orbital Jigsaw)..and had the holes cut within 3-4 minutes. Easy as pie. No light leaks at all.

I would have preferred to use the 12"x12"'s or even the 12"x24." But, I have only used the 8"x8" because the only places I can locate them in my closet is a 22 and 1/2" shortwall (with a wall stud right in the middle) and a 10" return wall. Besides, the return air grill is more easily explained, "Uhh...it gets stinky in there and it is for aeration."



But, I have heard little praise for the 4" circular.

Namaste, mess

 

[tito libowitz]

been using mine for years in my box...worth every penny

 

[stink.whistler]

How thick are those louvers (the good ones).

 

[CarnivalofZerg]

perhaps 2" thick. IMO they kill the airflow too much. I've spent waaay too much on just adding more and more louvers to my fan didn't suck in the poly on the walls and rip the room apart. If I had to do it all over again, I'd definitely look into something else.

edit: oh wow first post. Long time lurker, had other accounts but hi all again

 

[smoke1sun]

perhaps 2" thick. IMO they kill the airflow too much. I've spent waaay too much on just adding more and more louvers to my fan didn't suck in the poly on the walls and rip the room apart. If I had to do it all over again, I'd definitely look into something else.

edit: oh wow first post. Long time lurker, had other accounts but hi all again

What would you use instead?

 

[petemoss]

Those Adorama 8X8 louvers are easy to install if you can cut a square hole, but as noted, they block a lot of airflow. I took mine apart and saw that it was a four-panel light trap. By using only two panels, I could make two light traps. That way, I block off over 90% of the light and the cut-down louvers allowed much more airflow. The back of my cabinet faces a dark wall, so I didn't need 100% lightproofing.

 

[laidbackgreen]

I run a Can Fan 8" HO fan for exhaust and planned on using two 8x8 darkroom louvres. They restricted the air flow way to much. My guess is I would prolly have to use like 6 of the 8x8's to compensate for the air flow reductions.

In the end I ended up taking the louvres out and am using nothing right now. IMO these things are way to expensive and to get proper airflow you have to use ALOT of them. Way to restrictive on airflow.

 

[Capn]

I have a 1' one. They impede airflow a lot, and I was using a 6" vortex to pull through it. Very little airflow, almost unnoticeable.

Multiple may be key, but they are decently expensive.

 

[Tony Aroma]

I have three of those 8-inch square louvres shown in the picture in my cabinet -- one for exhaust, two for passive intake. I have a Panasonic Whisperline 240 CFM fan for my exhaust with a duct directly to the louvre. I don't have any basis for comparison, but air flow seems to be just fine to me. The cabinet is caulked and weather stripped, so is reasonably air tight, and I've never noticed any massive amount of suction when I open the doors. And with the doors shut, there is a good flow of hot air coming out the exhaust. I got the louvres mainly because they were easier than trying to build my own light baffles, and because they look nice and neat and take up no space inside or outside the cabinet.

 

[Hal]

I am using one of the 8 x 8's as well. I'm curious how those who are claiming reduced airflow, even claiming to actually know the % of reduction, how are you figuring?

I have heard others make similar statements, but have never known how they actually figure this out.

 

[Capn]

Mine wasn't for a cabinet though. Also the fan I was using pulls around 500cfm. Only had 1 louver as well for intake.

 

[messn'n'gommin']

I am using one of the 8 x 8's as well. I'm curious how those who are claiming reduced airflow, even claiming to actually know the % of reduction, how are you figuring?

I have heard others make similar statements, but have never known how they actually figure this out.

I did not mean for my post to mislead as it was a "guesstimation" of various flow restrictions. I am using two 250w CMH's, a modified Stanley Blower (with no scrubber) set at the lowest setting (position 2 and 3 were just too loud), rated at about 190 CFM, into approximately 7' of 6" exhaust. At the time, I had just two of the 8"x8" louvers. Ambient temps were about 70ish and closet temps were about 82ish. Using the famous heat transfer formula (CFM = Watt's x 3.2 divided by the Temp differential) I was getting about 130 or so CFM of movement. Hence, the addition of a third louver. Not very scientific mind you but a good enough ballpark figure for me to work with.

Again I didn't mean for it to sound as if I had hard and fast data, just something I needed to know with an eye to future upgrades (i.e. a bigger fan and more watt's of photonic goodness).

Namaste, mess

 

[Hal]

Hey mess'n'...

No, man, thats great, didn't know that famous heat transfer formula. Is the temp differential the ambient room temp subtracted from the cabinet temp? If so, which cabinet temp do you use....the canopy, mid-level...?

Thanks for that formula