I would like to block the bottom air vent to prevent light spillage through the slats. I shoot the AB-800s in a gym and typically shoot about 1 shot every 5-10 seconds for about 30 seconds ..then wait about 30-60 seconds and repeat...so i am not stressing the units at all.

I (think I ) get quite a bit of light leaking out and hitting the floor directly instead of being bounced into the ceiling as intended (as seen below) and (I think) it would be nice to not have it. Can anyone see a problem with this? Is this even the spot that the light flare on the floor is coming from? The side vents are still wide open.



thanks

Ron

I make some gobo or something. I would not suggest blocking the vents in any fashion.

Actually apon looking closer I see that is where the fan is...probably a bad idea to block...A gobo is doable just a wee pain is all. Thanks for making me think twice.

Ron

Put the cap on, turn your modeling light off, and take a few shots with it like that. IIRC, there really wasn't much light leakage on my units, but that's the best way to test.

Thanks for the tip.

My flare on the floor is not coming directly from the AB at all and seems to be a by product of the bounce.
Not sure how it is getting over there as the strobe is angled to the camera right but the cap test is pretty conclusive that the light is contained within the shell of the strobe.

Ron

Does AB stand for "Atomic Bomb?" If that light on the floor is from a cooling slot, send it back because everything melted in the blast. What you are seeing is the reflection of the bounce. That floor is polished within an inch of its life. Just look at the double doors at the far end.

Ron Hole wrote:
Thanks for the tip.

My flare on the floor is not coming directly from the AB at all and seems to be a by product of the bounce.
Not sure how it is getting over there as the strobe is angled to the camera right but the cap test is pretty conclusive that the light is contained within the shell of the strobe.

Ron



Exactly. That's what I suspected. I'd recommend getting the strobe up higher and placing a few around at different angles at lower power settings instead of bouncing. I don't shoot sports but I think they normally shoot them straight on with a standard or sports reflector. You'll get better recycling, too.

Question, what is the plan for that light? Where do you plan to be shooting with the light in that location? To shoot basketball/gym sports you normally are on the same end as the light(s), and in that case, from this shot it looks that light is way too hot to do that.

Where is the light in that blowout? Looks like it is on/near that blue/green box on the wall. If so some more height to the light might help as well. Looks like the light is only about 1/3 up that wall and you are getting a lot of your bounce off the side wall. A tall lightstand on top of the bleachers on the base line would be a better location if the light is aimed in the general area of the key.

Are you running the standard reflectors? I keep a piece of gaff tape over the umbrella hole unless I am using an umbrella, cause I found that they sometimes get some bad stray light coming out of that hole in the reflector for the umbrella (especially if using a grid).

Might also try asking over in the sports forum. Sport Venue lighting is one of the only gear related acceptable topics over there, and there is lots of people with experiance with this.

Thanks for all the help here. It is much appreciated by us guys that do not use our lights as "traditionally" as most.

I have a single AB-800 mounted to the shot clock at each end of the court so I can shoot both halves of my sons basketball games. Putting two on one end is pretty tough as there really is no where to mount a second one and there is not room for lightstands. Also where it is mounted is about as high as I can go at this point.

I would like to mount 4 up in the rafters and leave them there but I have no way of activating the Cybersync triggers. Maybe PW's do this and that might be an (expensive) option to condsider.

It does limit my shooting to the one side on each end but until I can get a bracket installed to hang another light on each end of the court I am stuck with what I have.

I aim the light so that it should bounce down on the key. I am going to gobo the strobes tommorrow to see if I can reduce the light hitting the wall as well going forward. If that seems to help I will order up the 11" reflectors to try and keep the light more contained though I will have to modify my bracket to allow the 11" to fit

I do post on the sports forum and have had lots of help regarding placement and aiming but I thought posting here regarding my misplaced thought on the air vents would be more suitable.

Ron

One other question Are you firing both lights all the time during the game? I would set the receivers to different channels. That way you can shoot with channel 1 at one end of the court and channel 2 when you are at the other. That way you dont have the 'unused' end of the court flaring the end that you are currently using.

Ron,

What do you mean...."but I have no way of activating the Cybersync triggers." ?

Also, why can't you just do what the previous poster suggested. Secure a lightstand to the top of the bleachers (right side of pic). It looks like it would take a bit of special rigging, but if you're considering a semi-permanent mount of 4 lights to the rafters, cobbling something to put a light stand in that corner should be too much of leap.

Then you'd two lights on one side of the court. Of course you could only shoot half the court but I think the lighting would be better.

If you get the AC Cybersyncs, you won't have to worry about turning them on/off, batteries, etc. Good deal.

I do have the recievers set up on different channels and only use one at a time.

Sorry..I meant activate the recievers.

The Cybersync receivers "goto sleep" after two hours of inactivity (to preserve battery power) and require a physical press of the test button on the receiver to "awaken it" and have it respond to the transmitter.

While I wholeheartedly agree that two would give me a better environment to shoot in there really is nothing safe to attach to up in the bleachers...no rails, nowhere to superclamp, and nothing to anchor the lightstands too. Just having them sit there sand bagged, is not an option with a bunch of rowdy teenagers cheering on their team.

What I will probably do for next year is mount two brackets at each end of the court and just use four AB-800s mounted at about the same height they are at now.

One AB-800 gives off enough light (2.8-4.0 1/200-250 at 400iso) to get decent enough shots but sure limits my shooting angles and gets pretty boring pretty quick. I am going to gobo the "Guest" end for tommorrows game to try and control spill over to the far wall. I'm ok with the spill on the "Home" end.

Thanks again for suggestions, hints and tips. This is my first season strobing gyms and I certainly am picking up lots of info that helps in getting an acceptable product.

"Guest" End

The light you see on the floor is a refection off the wall. Angle of incidence = angle of reflectance. From you camera position those angles point from camera-to-floor-to-wall. If you want a more accurate visualization of where the light is going turn down the power and stop down the lens.

The spot on the wall, not the flash head, has become the source and the solution is to move the light and the spot of light it creates higher so the angle of the light is steeper, on the order of about 45-degrees or more, so when you are down on the floor the reflection isn't seen.

Its similar to shooting into a mirror - if the flash is close to the camera axis you'll get a glaring refection. But put the flash 45 degrees to the mirror and you will not see the glare because it reflects 45 degrees in the opposite direction.

You might consider mounting the AB in the rafters pointing down as back-rim light with a hot shoe flash on a bracket for frontal fill which will provide more dramatic lighting than your examples here, which are quite good but lacking the dimensional modeling and foreground / background separation that rim light adds . You could even use ETTL for the camera fill by attaching the radio trigger for the AB to the PC sync outlet or using one of the modified OC-E3 cords sold by Paramount which have a second shoe for mounting a PW next to the flash on a bracket.

Chuck

BSHuff wrote:
I keep a piece of gaff tape over the umbrella hole unless I am using an umbrella, cause I found that they sometimes get some bad stray light coming out of that hole in the reflector for the umbrella (especially if using a grid).


This was recently brought up in the AB forum but my quick test showed that light leaking from umbrella hole is around 4 stops lower than the light coming from the front so I don't think you need to worry about it.