Strobe & Flash Comparison Testing: Part I (Output)

Hi Jason,

It's a little difficult to give you an idea of settings. There are so many variables and the type of softbox used, it's efficiency, type of lighting, etc. play heavily in to it.

In terms of determining exposure I use a light meter. It eliminates the guess work completely. Once you have a reading you can then calculate alternate exposure settings based on the metered readings and can get very good at moving lighting or the subject and evaluating the exposure based on new distances or power levels, but this is always based on that first metering.

As a point of reference, in my studio, using a D-Lite 2 in a 36" x 48" softbox, placed 6 feet from the subject's face, at ISO 100 (I normally shoot ISO 200)......

Full power: f/8
Minimum power: f/2.0 + .2

Keep in mind that most often, and to get the best quality of light, you'd be working closer tot he subject and typically I would use a large diffusion panel for a full length shot, so the readings would be at least 1 stop higher. (2 stops if you factor in ISO 200)

Hi Robert,
Thanks for the reply. I appreciate your feedback. What I guess I am trying to work out is what setup to purchase so I need to make sure that I have select the right size strobes and softbox. When I get the gear I will use a light meter to work out the correct settings etc.

What you have said gives me a good place to start. I just want to clarify that you are able to shoot full length portraits with that softbox at 6 feet? Or does it only cover 1/2 or 3/4 length?

Jason.

JasonW wrote in post #5556372
What you have said gives me a good place to start. I just want to clarify that you are able to shoot full length portraits with that softbox at 6 feet? Or does it only cover 1/2 or 3/4 length?

Jason.

Don't think of a softbox as 'coverage area'...it is 'softness of light' After all, you can use a 5"x7" micro softbox to easily cover a 10x15' area from 10'! The farther away, the larger the softbox needs to be for softness, not for area of coverage.

Hey Jason,

I can do full length with a large softbox but it wouldn't be my first choice and would present some problems on its own. For full length my first choice is still a large 6 or 7 foot diffusion panel. If I were to use a large softbox I would probably supplement it with another box or strip light to fill the lower portion of the body and feet. Of course, if you have the space and the cash you can do something like a 7 foot octabank but that's a bit over the top for most people in a home studio.

I recommend making or buying a diffusion panel and firing 1 or 2 strobes from behind the panel. You'll be able to get nice soft, even wrap around lighting with a much nicer look than with the softbox. There are many threads with DIY diffusion panels of all types.

Some notes about the real-world use of lights:

This weekend, I used a pair of SP Excalibur 3200's for a costuming photoshoot. The guy from whom I bought the lights used had mentioned they were inconsistent in their shot-to-shot performance, and I noticed that some images were darker than others. After a while, I figured out the cause: not letting the Excaliburs fully recharge between shots. The lights will discharge before the "ready" light is illuminated, but at less than the selected level. Waiting for the lights to property charge resulted in consistent illumination in each frame.

As for coverage, it's no surprise that the Excalibur monolights were far more powerful and effective than the Sunpak 383's I used. For the same exposure, I went from f/5 at ISO 400 with the Sunpaks to f/8 at ISO 200 with the Excaliburs.

A couple of examples from the weekend:

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I'm sure you found them to be consistent but have you conducted the same type of tests outlined in post #1 of this thread to really test consistency? When testing consistency, are you testing pop to pop for output only, or are you also testing color consistency?

Also keep in mind that some manufacturers of strobes will signal ready when the pack gets to nearly full, but not 100%. I've seen that mentioned more than once in the user manuals of some strobes. 90% was the figure that sticks to mind, but can't remember whose manuals I saw that in. That could could cause similar issues depending on your power settings.

sfaust wrote in post #5556965
Also keep in mind that some manufacturers of strobes will signal ready when the pack gets to nearly full, but not 100%. I've seen that mentioned more than once in the user manuals of some strobes. 90% was the figure that sticks to mind, but can't remember whose manuals I saw that in. That could could cause similar issues depending on your power settings.

You're describing the behavior of a 580EX, BTW!

TMR Design wrote in post #5556923
I'm sure you found them to be consistent but have you conducted the same type of tests outlined in post #1 of this thread to really test consistency? When testing consistency, are you testing pop to pop for output only, or are you also testing color consistency?

1,300 pictures a day left no time for testing.

Color balance looked good. The oddity with that was the location, under a skylight that let in a lot of variable sunlight. The monolights were set to handle all of the scenes' illumination, but there were still a few minor shadow and color variations because of the changing ambient light.

I used a Digital Rebel XTi set on the camera's flash white balance.

TMR Design wrote in post #5549609
I figured I would post these images anyway just in case some people don't know what I'm describing or that this can be done.

Thanks for the pictures Robert. I bought a 5' octabox and it puts a big strain on the plastic mount of my D-Lite2's. This looks to be a great solution.

Sure thing Randy. That's definitely the way to handle large modifiers with any strobe that doesn't have the mass and stability to support them.

Depending on the height and angle you may want to consider a small extension arm of some kind so that the modifier can be angled down sufficiently. It works great and gets the modifier a little further away from the mounting hardware.

TMR Design wrote in post #5560191
Sure thing Randy. That's definitely the way to handle large modifiers with any strobe that doesn't have the mass and stability to support them.

Depending on the height and angle you may want to consider a small extension arm of some kind so that the modifier can be angled down sufficiently. It works great and gets the modifier a little further away from the mounting hardware.

That's a great idea. You got a picture of that?

shooterman wrote in post #5560216
That's a great idea. You got a picture of that?

Here you go Randy.

I'm using a Photoflex LiteDisc Holder, which doubles very nicely as a medium weight boom arm. I don't extend it much further than I show in the images and find that gives me enough working distance to tilt down as much as I want without the edge of the softbox hitting the stand. In the case of a 5 foot octabox I think this is the perfect solution.

You can, of course use extension arms made by Bogen, Avenger, etc and you'll need the heavy duty swivel mount. Use a heavy duty or a century light stand and don't forget to sandbag the legs of the stand.

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That is awesome Robert, thanks! That will be the perfect solution, as trying to get it to angle down enough was a problem for me also. Thanks very much for the great images.

Randy

great tips Robert. Can you find me the money tree also?