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PLM umbrellas offer sweet combo of efficiency and softness - Continued
Comparing softness, brightness and light cast

For team photos, the PLM 64" Silver umbrella offers a stupendous combination of brightness, softness, ease of setup and manageable size. For those instances where its narrower light cast doesn't suit the scene, the Front Diffusion Fabric accessory readily converts it to a wide dispersion light source. If you don't shoot team photos, the good news is that the sweet characteristics of the silver PLMs can be put to good use in many other lighting situations too. If you can think of a situation where you need soft light, the directionality of a gridded softbox plus maximum brightness out of your hard working strobes, these new umbrellas from Paul C. Buff are a compelling option.

Below you'll find three series of test photos comparing the two largest PLM umbrellas to a handful of other light modifiers, mostly from Photoflex. The modifiers are a mishmash of ones on hand here, and run the gamut from soft to hard.

The first series shows each modifier's softness, or lack thereof. The second shows light cast. The third shows relative brightness. The photos have been prepped in black and white so that slight cool/warm differences between each modifier, plus some colour contamination from overhead fluorescents in the photos shot with the weaker modifiers, won't impact your interpretation of the characteristics being displayed.

The flash unit is the same for each photo, as is its position, the distance to the subject, the camera and the lens. For the record, the flash is an AlienBees B1600 and the camera is a Nikon D3S plus AF-S 24-70mm f/2.8G at 28mm. The distance between the flash and the subject is about 25ft (7.6m).

Softness In this series, the shadows tells the whole story.

As you click through the slideshow, note the differences in the shadow's edge gradation and overall density, particularly to the right of the ladder. A smooth, gradual shadow edge behind the subject, combined with a wider, fainter shadow behind the ladder, means the photo was shot with a soft light source.

Conversely, if the shadow's edge ends abruptly, and looks like it was drawn with a thick black marker, the light source is hard.

Each photo contains a shorthand description of the light modifier used. The modifiers are:

PLM 86" Silver 86" silver surface PLM system umbrella, without diffusion

PLM 64" Silver 64" silver surface PLM system umbrella, without diffusion

PLM 64" Silver + Diffuser 64" silver surface PLM system umbrella with Front Diffusion Fabric attached

Photoflex 60" White 60" RUT White Convertible Umbrella, configured for bounce use

Photoflex 45" Silver 45" ADH Silver Adjustable Umbrella

Photoflex 30" White 30" RUT White Convertible Umbrella, configured for bounce use

Photoflex MultiDome Large (36" x 48") MultiDome with internal baffle in place

Photoflex MultiDome + grid Large (36" x 48") MultiDome with internal baffle in place and matching 40 Photoflex grid attached

AB 7" reflector (old style) Older AlienBees 7" reflector with shiny, non-stippled interior surface

AB 7" reflector (old style) + grid Older AlienBees 7" reflector with 20 grid attached

Brightness The slideshow below demonstrates the relative brightness of each modifier option. The exposure settings stayed constant throughout, and were based on the correct exposure for the first modifier in the series, the PLM 86" Silver.


The table below assigns some numbers to the photos above. The right column lists the output brightness, in f-stops, relative to the PLM 86" Silver, which is the brightest of the modifiers included in the test. The numbers were generated by averaging three Minolta Auto Meter IV F readings, across about a 6ft (1.8m) area at the centre of the light's output, from a distance of about 14ft (4.3m).

plm_brightness_table.jpg

We don't have comparison photos for the the PLM 60" White umbrella, but we did include it in a separate brightness measurement session that produced the table of data above. It stacks up as follows:

plm_brightness_table_02.jpg

Light cast
The next slideshow highlights each modifier's light dispersion characteristics. These photos are the same as the softness slideshow, but without the tight cropping.


The slideshows reveal why we're liking the silver PLM umbrellas: when pitted against a comparable umbrella or softbox from Photoflex they're either brighter, or softer, or both. For instance:
  • The PLM 64" Silver puts out roughly the same amount of light as Photoflex's 45" ADH Silver umbrella, but the light from the former is pleasingly soft with only a hint of stepping in the shadows (this is a common silver surface trait), whereas the light from the latter is harsh, bordering on hard, with an obvious double-shadow effect.

  • The PLM 64" Silver produces light that is both noticeably softer and over two stops brighter than the Photoflex 60" RUT White.

  • The PLM 64" Silver + Front Diffusion Fabric produces light that is dramatically softer and almost a half-stop brighter than the Photoflex 60" RUT White.

  • The PLM 64" Silver focuses the light in a manner similar to the Photoflex MultiDome softbox with grid attached, which means they're both well-suited to situations where the light needs to be controlled: to keep the main light in a portrait from spilling onto the background, for example. Based solely on the quality and control of light, the MultiDome is really nice, and is a longtime staple of our lighting kits. But it requires an amount of light that's about 3 1/3 stops brighter than the PLM 64" Silver to do roughly the same job.

  • The PLM 86" Silver is superior to the PLM 64" in brightness, softness and in evenness across the focused beam of light each projects. Its only downfall, at least for our purposes, is its monstrous size. Outdoors, even light winds will blow over a heavily sandbagged lightstand with this umbrella on top. Indoors, it can be unwieldy. It literally won't fit into a space that doesn't have high ceilings and plenty of room to maneuver it into place. Photos of the PLM 86" Silver don't do it justice; you really have to experience this umbrella in person to get how big it really is.

    Thanks to its bigness, it's a better performer than the PLM 64" Silver. If you have the room it requires, plus a not-too-windy environment, the PLM 86" Silver is the way to go. The PLM 64" Silver, however, offers most of the goodness of its larger counterpart in a more manageable package. That's why we've standardized on it, and that's why it's the PLM model we're talking up in this article.
Photoflex is the subject of this particular light modifier beat down, because it's what we've owned for years and because the company is one of the more popular makers of umbrellas especially. That said, there's no reason to believe that other brands would fare much better. If you look at umbrellas from various companies, they tend to follow the same pattern as Photoflex's lineup: two or three sizes up to about 60", both silver and white surfaces and designs that use eight or sometimes ten ribs. In other words, they lack the parabolic shape that allows the PLM umbrellas to be both brighter and softer than a standard umbrella design.

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.

plm_brightness_table_03.jpg

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.

Notes and observations

To be their brightest, silver PLM system umbrellas require the flash tube to be positioned as close as possible to the focal point of the parabola. To accomplish this:
  • Use the umbrella mount that's part of your monolight or flash head, rather than the umbrella mount in a separate swivel accessory that you might be using to attach the light to the lightstand. The latter will almost certainly position the light up too high within the umbrella.

  • Make sure the flash head is neither too close or too far from the umbrella. With a little practice this isn't hard to do: once you have the the umbrella mounted on the light, stand at the side of the umbrella and then close one eye. Look across the face of the umbrella and change your position until the near and far edges of the umbrella are lined up. The entire flash tube (or diffuser dome over it) should be just inside the umbrella area, but just. Slide the umbrella closer to or further away from the light until this exact position is achieved.

    If tightening the umbrella locking screw on your light causes the umbrella angle to shift (it does with B-series AlienBees monolights), do one final visual check to make sure that the flash tube is still sitting pretty just inside the front face of the umbrella.

  • The above applies to flash units whose flash tube is exposed, like our AlienBees B1600s. If your studio flash has a built-in, non-removable reflector, then you'll probably need to experiment to determine how close to the PLM umbrella the flash ought to be. As a starting point, try placing the front edge of the built-in reflector just outside the front face of the umbrella and then let your light meter guide you from there.

  • For shoe mount flashes, the optimum position is just outside the front face of the umbrella, but you may need to test to see how far outside is right for your flash and its zoom head setting.

    Also, you'll need to ensure that the flash is pointed at the centre of the umbrella, and typical mounts for this type of flash tend to put the flash head up higher than is optimum. We've used the upcoming PocketWizard AC7 accessory, which turns the flash on its side and, as it happens, aims it dead centre in the umbrella (at least when the umbrella mount is this one from Photoflex).

  • Paul C. Buff makes a special reflector for its lights and the PLM system umbrellas. The PLMR 7 Umbrella Reflector is meant to eliminate side spill, and it does that. In most instances it's preferable not to use it, however, because it shaves 2/10ths of a stop of brightness in our testing with the PLM 64", both silver and white surfaces. There are two notable exceptions where, despite the small brightness hit, mounting the PLMR to your Paul C. Buff light is still a good idea:

    • When the PLM umbrella configuration is either a PLM Silver + Front Diffusion Fabric or PLM White + Black Front Spill-Kill Fabric. The PLMR reflector helps keep the fabric away from the flash tube and modeling light. The various photos and test numbers in this article were generated with the PLMR reflector in place when these two fabrics were used (and only when these fabrics were used). Which means it's possible, for example, to squeeze a bit more light from the PLM Silver + Front Diffusion Fabric combo than we've reported: 2/10ths of a stop more, to be exact.

      To do so, though, you have to be certain that the umbrella can't accidentally spin - which changes the position of the offset centre hole of the fabric - or that any other fiddling with the lighting setup you might be doing won't force the fabric in contact with the flash tube and especially the modeling light. For us, it has been less worrisome to just use the PLMR reflector. A new Front Diffusion Fabric design should eliminate the need to use the PLMR reflector in this instance; more on that ahead.

    • When using gels. The PLMR reflector gives you something to attach the gel to. Otherwise, it can be tricky to position the gel sheet so that it covers the entire output area of the flash tube. Not impossible, mind you, and if we were to run into a situation where a gel was necessary as was a tiny bit more brightness, then off would come the PLMR reflector.
Upon Reflection: The PLMR 7" Umbrella Reflector attached to an AlienBees B1600 640ws monolight. Click photo to enlarge (Photo by Rob Galbraith/Little Guy Media)
  • The durability of the PLM umbrellas is really good. It's at least on par with Photoflex, if not better. The PLM 64" Silvers in particular have seen reasonably heavy use, including a couple of lightstand falls, buffeting with heavy winds plus a few drops of rain thrown in for good measure. They've held up just fine. Looking at them closely there's no sign of these umbrellas failing or wearing out prematurely.

    The Front Diffusion Fabric is a different story. The five we have are showing no signs of wear, but three of them don't fit right. They're too loose, which means that several of the fabric's 16 grommets, which attach to the ends of the 16 ribs of the umbrella, inevitably come detached because there isn't enough tension to hold them in place.

    The Front Diffusion Fabric ships with a small card describing a helpful workaround: use your fingers to reverse the grommet, folding over the fabric in the process, as you attach it to the umbrella. Doing this to a handful of the 16 grommets does enable the fabric to hold tight as it should. The real solution is to redesign the accessory. That, says company founder Paul Buff, is in the works.
  • Hold On Tight: An AlienBees B1600 with Ikea FRAKTA strap attached. Click photo to enlarge (Photo by Rob Galbraith/Little Guy Media)
  • Any umbrellas, when used outdoors, act like sails when the wind kicks up, and the PLM umbrellas are no exception. The large front diameter of the PLM 64", and the huge front diameter of the PLM 86", means they are particularly efficient wind catchers.

    To combat this, we've done two things: put extra sandbags on the lightstands and attached a tie-down strap to the Lexan housing of the B1600. The former is to keep the lightstand from toppling over; the latter is to limit the stress on the AlienBees unit.

    This monolight has a short umbrella slot at the front that is not reinforced with metal, and when the wind blows, even lightly, the umbrella slot begins to flex in a way that doesn't look good. The solution has been an Ikea FRAKTA strap, cut to be just long enough to fit tightly around the rear of the B1600. This has worked like a charm to clamp down the umbrella shaft at the rear. We've had no concerns, since adding the strap, about using the PLM umbrellas and this light together outdoors.

    The umbrella slot in Paul C. Buff's upcoming Einstein 640 monolight runs the full length of the flash housing, which will obviate the need for a tie-down strap or other reinforcement.

  • The shaft diameter of the PLM umbrellas is 8mm. This means they won't fit into the umbrella slot of any light not designed for at least this size. Most or all Elinchrom lights are limited to 7mm umbrella shafts, which means the PLM umbrellas can't be inserted into the umbrella mount on this brand of flash. Buff indicates that a version of the PLM umbrella that will incorporate a 7mm shaft is in the works, but it will be well into 2010 before that version hits the streets.
Upcoming changes to the PLM system

The PLM umbrella and fabric versions we've tested are representative of what has been available since this new system went on sale several months ago. Starting in the near future, Paul C. Buff will be rolling out slightly revised versions of the PLM 64" and PLM 86", as well as a new Front Diffusion Fabric design for these two sizes. The changes will be comprised of:
  • A shorter umbrella shaft This will mean less shaft sticking out the back of the umbrella mount. It will be still be 8mm in diameter, however. The version of PLM umbrella meant to be compatible with 7mm-only lights is now scheduled for release sometime next year, says Buff.

  • Proper-fitting Front Diffusion Fabric The current 16-grommet design will give way to one that features 16 individual rib pockets towards the perimeter plus three inches of wraparound meant to keep the fabric snugly in place as well as pull the umbrella into a slightly more ideal parabola shape.

    In addition, the offset centre hole will include a lip and drawstring that will enable it to be tightened around the flash housing, eliminating the need for the PLMR reflector (as described earlier in the article). The diffuser fabric is slightly different, but is promised to have the same light transmission and colour temperature specs as the current version. It should also be slightly quicker to install onto the umbrella than the current grommet version, says Buff.

    The new Front Diffusion Fabric will fit both the longer and shorter umbrella shaft versions of PLM.
Both the silver and white PLM 64" and PLM 86" umbrellas will be getting the shorter umbrella shaft treatment. As of this writing, the PLM 64" Silver and PLM 86" Silver are on backorder, so if you order now you'll automatically receive the new version with the shorter shaft, says Buff.

The same applies to the Front Diffusion Fabric. The older style in 64" and 86" sizes are also out of stock, so you'll only receive the newer version when you order from here on in. A precise ship date for the shorter-shaft silver PLM 64" and PLM 86" umbrellas and new Front Diffusion Fabric in matching sizes has not been set, says Buff, though the wait is not expected to be long.

As of this writing, the longer-shaft versions of the white PLM 64" and PLM 86" are in stock and are what you'll receive if you order now. You'll want to speak directly with Paul C. Buff customer service to discuss if it's possible to order the white PLM 64" and PLM 86" at this time but not take delivery until the shorter-shaft versions are ready.

The 64" and 86" Black Front Spill-Kill Fabric sizes will also morph from the older grommet to newer wraparound style, just like the Front Diffusion Fabric in these sizes. These sizes of wraparound Black Front Spill-Kill Fabrics are likely to trail the release of the wraparound Front Diffusion Fabrics by several weeks or more, Buff says. In the meantime, they have an ample supply of the grommet style in stock.

The white and silver 42" PLM, and the accessory fabrics for them, will continue unchanged for the moment. Buff indicates that this size is likely to see the same changes as the two bigger PLM models, but a timetable for that to happen has not been set. As of this writing, the company has all 42" umbrella models and accessory fabrics in stock.

An October 2009 information posting on the Paul C. Buff website indicates that the 42" size will become 48" in the future. In an interview this week, Buff indicated that the new size is still being finalized, and may or may not end up being 48", though it's likely to be in that neighbourhood. As already mentioned, the 7mm shaft version of the PLM umbrellas is now going to ship in 2010, and not December 2009 as the same information posting states.

Conclusion

Light modifiers are available for every purpose under the sun or in the studio. Stripboxes, beauty dishes, gridded reflectors and spotlights, these are just a few of the modifiers that change the light coming from a flash in a way that the silver PLM system umbrellas can't do. But when you need soft, bright, focused light, they are a stunning new option for photographers. Particularly those who work with lower power studio lighting equipment or even shoe mount strobes.

If we had to pick one umbrella and one accessory from the PLM range to use with studio flash units it would be the combination of PLM 64" Silver and the Front Diffusion Fabric. With these two in your kit you can cover a lot of lighting territory. Without the diffuser, the PLM acts like a big softbox with grid attached, only several stops brighter. Put on the Front Diffusion Fabric and the umbrella spreads the light wide without sacrificing too much brightness. Plus, the 64" size is manageable and usable indoors and out, even in a standard-size living room.

The PLM 86" Silver trumps the PLM 64" Silver in all ways except manageability. If you can deal with its oversized dimensions in all the locations you shoot, then it's the one to get. For our uses, the PLM 64" Silver is the better overall choice.

Because of the design of their head, shoe mount strobes like the 580EX II and SB-900 are a somewhat different matter. We're seeing good results from the PLM 64" Silver so far, but the PLM 42" Silver - which we've not used - might be the better option for small strobe applications. An as-yet-untested theory is that the light from the head of a shoe mount flash unit may fill out the PLM 42" Silver more completely than it can the 64" version. This in turn could mean the 42" model performs at least as well as the PLM 64" Silver. This would make the smaller umbrella the superior choice, since it's smaller to transport and less expensive to buy. Again, this is only a theory, one we hope to test in the near future.

Wide Angle: The PLM 64" White with Black Front Spill-Kill Fabric attached. Click photo to enlarge (Photo by Rob Galbraith/Little Guy Media)
The white PLMs are overshadowed by their silver counterparts, in large part because there isn't much you can do with the white versions that you can't do about as well with the combo of a silver PLM and Front Diffusion Fabric. There's one exception: the PLM 64" White or PLM 86" White with Black Front Spill Kill-Fabric attached is an even, superwide dispersion light source. If we had to, say, light all corners of a large ballroom to allow for spontaneous shooting from anywhere within it, and doing a ceiling bounce was out of the question, we would turn to this Japanese Lantern configuration of the PLM system.

If you're as jazzed about the Paul C. Buff PLM system as we are, and you're ready to make a purchase, then steel yourself for a bit of a wait. As we describe in detail in the preceding section, certain PLM system components - including the two largest PLM silver umbrellas and matching Front Diffusion Fabrics - are currently on backorder and won't be available immediately.

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