Help/advice with off-camera hotshoe flash lighting

[paul_c7]

<p>Hi guys,</p>

<p>I'm relatively new to lighting and lighting techniques, but I'm looking into a few things that I would like to try in order to learn more.</p>

<p>I'm currently shooting with a 5DMKII and a 580EXII (among other things). I've also got a 33-foot TTL cable that lets me use the hotshoe flash off-camera without any wireless technologies (I bought it first to play around with off-camera lighting).</p>

<p>I recently bought (for relatively cheap, so it's not a big deal if it turns out to be a waste) a wireless flash trigger with 3 receivers. The transmitter/receivers that I bought say they're compatible with 580EXII, 430EX, 420EX, etc.</p>

<p>What I'm really looking to do (or rather, try) is have 2 (possibly 3 once I figure out how it all works) hotshoe flashes mounted in various locations and have them all fire simultaneously when shooting for lighting from multiple angles (yes, I know this could be easier accomplished by investing in a studio or real lighting kit, but for now this is what I'd like to try).</p>

<p>Now, I've also seen online Canon's ST-E2, which looks like a wireless transmitter that can control multiple (up to 3 I think) hotshoe flashes (compatible units: 580EX, 550EX, 430EX, 420EX). From what I've read, the aforementioned hotshoe flash units can be controlled from the ST-E2 without needing any wireless receivers (like the ones I bought).</p>

<p>I'm looking at buying a secondary flash unit at the moment (either a 430EX or 420EX) to use alongside my 580EXII for a secondary light source, and may purchase a third depending on the success/failure of what I'm trying to do here.</p>

<p>Based on what I've outlined above, what would be the best way to do this? Would the ST-E2 be a better option than using the transmitter/receivers, or would they both accomplish the same thing? Does the ST-E2 automatically sync the flashes so that they all fire at the appropriate time when shooting?</p>

<p>Also, I read something about there being different channels that the ST-E2 and even the flash unit I have (580EXII) can control - for example, the ST-E2 can control 2 channels, while my 580EXII can apparently control 3 channels. What does this mean? What are channels in terms of how the flashes fire?</p>

<p>Again, I'm looking for suggestions related to what I've mentioned above - I'm not really interested in alternative methods of accomplishing the same thing using different means.</p>

<p>Also, just as a side note, I thought I read something about the 580EXII being able to control other flash units...can anyone elaborate on this? I'm not sure whether I misread that completely, or if I just misinterpreted it - it seemed as though I could use my 580EXII to control other slaves without even needing the ST-E2?</p>

<p>Thanks very much for any help! :)</p>

[mike_lorig]

<p>Hi Paul,<br>

check out strobist.com you will find links and forums there too.<br>

Cheers!<br>

mike</p>

[dbcooper]

<p>Optical systems (Canon, Nikon, optical slaves, both visible and infrared) rely on line-of sight (or nearly so with IR). Radio triggers, OTOH, do not, and are limited only by the range of the units. eTTL/iTTL flash control is another matter. The slave flashes are controlled by pre-flash visible or IR pulses from a controlling unit. Nikon calls this a 'commander' - some camera popup and speedlight flashes can act as commander; others cannot, and they also have a dedicated IR commander unit as well for cameras that support flash commander mode. Canon uses a similar system.</p>

<p>I'm a Nikon guy, but your 580EXII and the ST-E2 probably work as a eTTL 'masters' for compatible Canon eTTL slaves (e.g. 430EX, etc.). Check your flash's manual for more detailed information on wireless use. Manuals for other Canon flashes and devices are available at their website. You can probably google up some tutorials online as well.</p>

<p>Nikon uses <em>channels</em> (1-4) and groups (A/B/C) - the channel being the 'frequency' the wireless iTTL preflashes operate on (so if there's more than one photographer using Nikon flashes wirelessly, they don't trigger each other's flashes). <em>Groups</em> are to control individual (or more) slave flash settings (usually output power), so you don't have to walk back and forth tweaking the flash units to get the lighting ratios 'just right'...very handy if you clamp one high up on a wall, a ceiling, in a tree, or under a car). You can set several flashes on the same channel and/or group if you want to, or have one set on one channel, and another set of them on another channel for rapid lighting setup changes, or you can put more than one flash in a group. The groups are often assigned as A = main/ B = fill/ C = other (background, hair light, whatever), but you can get imaginative as you want to. You can also trigger optical slaves on other flashes when the xTTL slaves fire. I'd imagine Canon's scheme is similar. </p>

<p>Some radio triggers also have xTTL capability. The advantages are non-reliance on line-of-sight and greatly increased operating range. Radiopopper is one brand, and some Pocket Wizard models work that way as well. Non-xTTL flashes are more limited, but are very usable if you know what you're doing with lighting. They can work with either optical, IR, wired, or radio triggers (or a combination of them). Mike's suggestion (above) is a good one. Start with the tutorials 'Lighting 101' and go from there. As you read, it'll start to make more sense to you. I'd also suggest getting the book 'Light: Science and Magic". Hope this helped.</p>

[mariosforsos]

<p>The advantage of controlling the remote flashes with the manufacturer's own is that, at least with Nikon, you can also control the flashes' output directly from the controller unit, rather than having to go to each individual unit whenever you want to adjust something. This is a great help, especially when you've positioned your flashes in hard to reach areas.</p>

<p>True, IR signals do suffer from shorter range, especially outdoors, but inside a closed enclosure (i.e. a studio or a large room or space), they fare much, much better.</p>

<p>Radio transmitters, while more far reaching in terms of range, require you to constantly manually adjust the flash output at the flash, which means that, unless you have an assistant, you're pretty much forced to cover great distances...;-)</p>

<p>Personally, I do not use my flashes off camera with TTL as this gives me totally unpredictable results. I set them to manual and adjust output directly from my commander. That way I can adjust the output to as much as 1/128th of total, which is MUCH more versatile than you would be able to adjust through TTL.</p>

<p>A useful book would be "The Hot Shoe Diaries" by Joe McNally....check it out. And of course, the Strobist website.</p>

[hjoseph7]

<p>"Does the ST-E2 automatically sync the flashes so that they all fire at the appropriate time when shooting?"<br>

Yes, the way Canon's wireless system works is that the Trasmitter which can be either a 580EX flash unit, or the ST- E2 can control (3) groups of slaves which are named A, B & C.<br>

You can group any number of slave in any group. For example if you group (3) 580EX flash units in group A, then these 3 Flash units would fire simultaenously. To arrive at Ratios you have to split up the flash units into different groups. Such as (1) 580EX in group A + (1) 430EX in group B. </p>