(unknown member) • Contributing Member • Posts: 873
Re: Outdoor Prom Photos - lighting setup
In reply to Jules Winnfield • May 6, 2019
From long ago but applicable. Full article link Rob Galbraith DPI
Excerpt about Buff PLMs & Speed Lights:
Not just for studio flash
Shortly before publishing this article we began experimenting with the PLM 64" Silver as a light softener for shoe mount strobes. The good news is this umbrella and either the Canon Speedlite 580EX II or Nikon Speedlight SB-900 are shaping up to be a good combination. Other small flashes may also work well, but we've only tried these two so far.
The test portrait below, shot with a 580EX II and the PLM 64" Silver umbrella with a flash-to-subject distance of about 9ft (2.7m), appears to be indicative of what you can expect. Click here to view a much higher-resolution version, then have a close look at the lighting on the face. What you'll see is reasonably soft lighting, suggesting that this flash and umbrella are working reasonably well together. The light would be even softer if it were closer to the subject of course. Even so, the light is pleasingly soft.
Efficient: A test portrait, left, lit by a combo of the Canon Speedlite 580EX II and PLM 64" Silver, right (flash is inside a PocketWizard AC7, which permits mounting the flash on its side). Click either photo to enlarge. Click here to download a higher-resolution version of the photo at left (Photos by Rob Galbraith/Little Guy Media)
What you can't tell from looking at the photo is that the brightness of the output from the PLM 64" Silver, with the 580EX II's head set to 24mm, is nearly identical to the output of this flash used direct at the same 24mm zoom position. In other words, if you have a 580EX II, its zoom head is set to 24mm and it's pointed directly at the subject without diffusion of any kind, the output will be about the same brightness as if you'd bounced the flash's light into the PLM 64" Silver. Only the character of the light will be different: one will be hard and the other will be soft.
You can also soften the PLM 64" Silver's output slightly more, by using the drop-down flash diffuser (ie the flash's zoom head position reads 14mm on the rear LCD). This reduces output brightness a little (less than 1/3 stop), but because the flash's light fills out the umbrella somewhat better, there is a small but visible improvement in softness.
If you're accustomed to losing heaps of brightness from your shoe mount flash unit as soon as you try to diffuse its light in a decent-sized bounce or shoot-through umbrella or softbox, and you've struggled to make certain kinds of pictures as a result, the PLM 64" Silver offers a pretty slick solution.
The table belows shows the relative brightness of several 580EX II configurations, both unmodified (that is, using only the built-in diffuser or varying the zoom head position) and with three different umbrellas. The right column lists the output brightness, in f-stops, relative to a 580EX II set for 24mm coverage on a full frame camera. The numbers were generated by averaging three Minolta Auto Meter IV F readings, across about a 3ft (1.8m) area at the centre of the light's output, from a distance of about 14ft (4.3m). Except for the 50mm and 105mm numbers, which represent the brightest output measured within the focused area of light projected by the zoomed flash head.
As you can see, the 580EX II's 24mm zoom head position hits the brightness sweet spot with the PLM 64" Silver. Zoom in more than that and brightness begins to drop. Plus, light softness is reduced. Pulling out the built-in diffuser for 14mm coverage ups softness a bit at the expense of a slight drop in brightness. Going forward we're probably going to standardize on using the 14mm diffuser, to eek out as much softness as possible, but a case can be made for either the 24mm or 14mm setting, it just depends on whether you need a bit more light or a bit more softness.
Though the full range of testing to generate the table data was done with a 580EX II, we've actually used Nikon's SB-900 about equally in trying to sort out whether flashes like this are a good match for the PLM 64" Silver. What we've seen in shooting goofy self-portraits in the garage and doing brightness measurements with Nikon's top Speedlight is that it lights up this umbrella as well as the 580EX II.
For some time, the Photoflex 30" White umbrella has been a staple of our small flash location kits, for no other reason than it fits in various carry-on friendly gear cases. That's why it's included in the table above. The PLM 64" Silver, coupled with this Speedlite, produces dramatically brighter, softer light than the small Photoflex umbrella, but it will never fit into a single regulation carry-on alongside shoe mount flashes and short lightstands. So the Photoflex 30" White may continue to be what goes on the airplane.
Next on the agenda is to try out the PLM 42" Silver. It doesn't offer any advantages over the PLM 64" Silver and PLM 86" Silver when used with monolights, or at least none that apply to how we might use it. But the smallest of the PLM umbrellas might be as good a companion for shoe mount flashes as the PLM 64" Silver. There's only one way to find out, and that's to give it a whirl, as soon as the UPS shipment arrives. Once that's done this article will be updated with what we learn.
