Basic questions about using a studio strobe to light a background

I am using a single studio strobe and would like to add a second to light my background.

1. Is there any reason to add difusion to a strobe that will be used just for lighting a background?
2. I want to get some gels to tape over the strobe. Are there any heat issues or reasons to be concerned with doing this? Are there certain types of gels that would work better with being taped onto a strobe?
3. I am completely new to studio lighting. What do I need to look into to simply get the second strobe to synch with my main one? Do I just need to figure out how to put the second strobe for the background into slave mode?

Thanks in advance.

southwestform wrote in post #18662662
I am using a single studio strobe and would like to add a second to light my background.

1. Is there any reason to add difusion to a strobe that will be used just for lighting a background?
2. I want to get some gels to tape over the strobe. Are there any heat issues or reasons to be concerned with doing this? Are there certain types of gels that would work better with being taped onto a strobe?
3. I am completely new to studio lighting. What do I need to look into to simply get the second strobe to synch with my main one? Do I just need to figure out how to put the second strobe for the background into slave mode?

Thanks in advance.

1. If you need some increase in uniformity of brightness across the lens-visible area of background. Remember the Inverse Square law of light intensity...if you put a flash with simple reflector to one side of the subject, it may light an area but with DIMINISHING intensity when it at the far side of the background. That is less apparent with a 'large source'.
2. Unless you are using studio strobes with constant incandescent modelling light, and/or shooting a lot of shots in rapid succession (causing lots of heat even with a xenon flashtube) I would not worry too much about gel damage.
3. If second strobe has a visible light slave function, just set that up and shoot. Else, put both strobes on a radio trigger.

Traditionally, in portrait studios, the background light was low behind the subject with a reflector that kept it off the subject and caused an elliptical shaped light on the background brightest behind the subject and then fading off as it went.

That's one approach. Another it to hang the light above the subject pointed at the background and downward to have the obsolete shaped light.

If you want the light even it gets trickier and usually is best with two or more lights.

What strobe do you own and what are you considering for your next purchase?

I will also be using a large white collapsible background that has white cloth material on the bottom that I was planning to extend outward and underneath my subject. The subject will be sitting on a stool a few feet from the background, and I am just going to be taking simple headshots. I might also take some shots of toddlers, so I might have them stading and not sitting, that is why I was thinking of extending the white cloth underneath.

Will all of this white material bounce much light back onto the subject and also onto the background? My key right now is positioned close and above my subject at 45 degrees with a softbox, and pointed down and there is a reflector on the opposite side.

Thanks.

southwestform wrote in post #18662710
Will all of this white material bounce much light back onto the subject and also onto the background? My key right now is positioned close and above my subject at 45 degrees with a softbox, and pointed down and there is a reflector on the opposite side.

Use the light fall-off phenomenon to your advantage...the DISTANCE between the subject and the background will serve to diminish the intensity reflecting back from the b/g to your subject. That is one (of several) reasons to put more distance between subject and background, like 5-6' distance and not merely 2-3' distance.

Furthermore, more distance provides more room to light the background with sources directly behind the subject, where the subject helps to shield the source from being seen by the lens.

How do you place a light behind a small child/toddler? In this case do you just need to put it off to the side and angle it down and out of frame?

Thanks.

southwestform wrote in post #18662718
How do you place a light behind a small child/toddler? In this case do you just need to put it off to the side and angle it down and out of frame?

Thanks.

Right. Or put it behind the object on which they are seated, pointing upward at a not-too-oblique angle (which is what distance btw. subject and background will permit)

It really depends on your creative intention: whether you need the BG to be uniform in colour, or if you want a focused spot, or what have you.

Take a look at how one of the masters does it: https://youtu.be/cncQ0​FgwpqY

Of course, that's not the way he always lights a background; that's how he did it for that particular image in order to fulfill the creative vision/purpose behind such image. I recommend looking at his other work and you'll get the idea.

For headshots you can put a strobe low behind your subject. But more natural background lighting will be achieved by using a boom overhead. Eventually, you are going to want a boom stand, no way around it. So plan to get a good one. A good C-stand is $150-175, you’ll own it for life, plus you’ll need a couple of sand bags. Another option is a rolling boom stand if you primarily use it in studio.

Gels can be film that you put in a frame or clip to the diffuser in your softbox. Or you can use mounted gels that fit onto a metal reflector or barn doors that attach to your strobe. There are other options, too. Yes heat can be an issue.

To sync your second strobe, just put it in slave mode. If you use a wireless trigger, you can also use a second receiver instead of slave.

No lights on the background on this shot. Just light falloff from the strobe in front.

Photo from ImageMaker...'s gallery.
Image hosted by forum (899598)

Photo from ImageMaker...'s gallery.
Image hosted by forum (909752)

I have some C stands and I just bought some Rosco color filters.

1. I want to put a filter on the strobe for the background. Should i use just ordinary tape? Is there a type of tape that works better OR am I over thinking it?

2. I’m using an Avenger C Stand for the background strobe. Can anyone recommend a Boom arm to use for my strobe to light the background?

3. Can a Gobo arm (https://www.bhphotovid​eo.com …es&sts=ma&Top+N​av-Search=) be used for this purpose? OR is there a reason to use a boom designed for this purpose?

Thanks

southwestform wrote in post #18667587
I have some C stands and I just bought some Rosco color filters.

1. I want to put a filter on the strobe for the background. Should i use just ordinary tape? Is there a type of tape that works better OR am I over thinking it?

2. I’m using an Avenger C Stand for the background strobe. Can anyone recommend a Boom arm to use for my strobe to light the background?

3. Can a Gobo arm (https://www.bhphotovid​eo.com …es&sts=ma&Top+N​av-Search=) be used for this purpose? OR is there a reason to use a boom designed for this purpose?

Thanks

1. I normally use gel holders that clip onto the front of reflector bowls. If I use a softbox, I might clip film onto the inside diffuser. In a pinch I have used gaff tape with film over bowls, but it is not as neat and you use more gel material that way.

2. Matthews, Avenger or Kupo.

3. I use the Matthews arms, but also have booms for longer reach. If you buy an arm for an existing stand I believe you also need a grip head or knuckle, along with a baby pin. You must use sand bags if using a gobo arm or counterweight if using a boom.

For gels, I use blue painters tape from Home Depot/Lowe’s

southwestform wrote in post #18667587
I have some C stands and I just bought some Rosco color filters.
1. I want to put a filter on the strobe for the background. Should i use just ordinary tape? Is there a type of tape that works better OR am I over thinking it?

definitely over thinking

Anyone will work, I think already recommended in some other thread of yours. Unless I am confusing with some other poster.

3. Can a Gobo arm (https://www.bhphotovid​eo.com …es&sts=ma&Top+N​av-Search=) be used for this purpose? OR is there a reason to use a boom designed for this purpose?

Sure. But this is 40" so if you need more reach, you need longer boom, simple as that. Another thing for longer more solid boom will be if you need to hang more weight and balance it with counter weight.