Freezing motion at wedding receptions

[fotografz]

<p>Thx Ian.</p>

[melandkeifspics]

<p>I just learnt that in ETTL mode shutter speed no longer controls the ambient light and aperture no longer controls flash out put because no matter what, the flash will always try to compensate for whatever your settings are.</p>

<p>Now my questions is, how does using ETTL help or not help me freeze action at receptions? And when in ETTL mode what does shutter speed and aperture control?</p>

<p>Can I use ETTL in conjunction with highspeed sync to freeze motion? Will the resulting image have a black background?</p>

[fotografz]

<blockquote>

<p>I just learnt that in ETTL mode shutter speed no longer controls the ambient light and aperture no longer controls flash out put because no matter what, the flash will always try to compensate for whatever your settings are.</p>

 

</blockquote>

<p>Not sure what you learned here. With the camera set to manual exposure (<strong>NOT</strong> program or any auto exposure mode), at any given aperture setting, shutter speed <em>will most certainly</em> effect the ambient ... and more specifically the background ambient. This is why "dragging the shutter" use of slower manual shutter speeds in conjunction with the use of on-camera flash will open up dark backgrounds like at receptions ... or do the opposite if a faster shutter speed is selected ... which then darkens the background in relation to the foreground subject being lit by the flash.</p>

<p>The principle at work in this case is that when the light from the flash travels outward, its' illumination effect is lessened the further it travels. So, subjects closer to the camera receive more flash illumination than things further away. Doesn't matter what setting the flash is on, ETTL, or Auto or Manual, this is a <em>"rule of physics"</em>.</p>

<p> </p>

<blockquote>

<p>Now my questions is, how does using ETTL help or not help me freeze action at receptions? And when in ETTL mode what does shutter speed and aperture control?</p>

 

</blockquote>

<p>Let's back-up a bit and explore how TTL works. ETTL is simply a metering method. All TTL camera and flash metering is measuring to a middle grey reflective standard. Light reflected back into the camera is measured to this standard. If you shot a solid black wall, the TTL meter on both the camera and the TTL flash will provide an exposure resulting in a solid middle grey wall. If the wall was solid white, the result would be identical.</p>

<p>The <strong>"E"</strong> in ETTL means <strong>E</strong>valuative ... where certain parts of the metered area of any given scene are given more weight or priority. This is done by pre-programed computerized methodology. Your camera manual usually explains this, and shows the pattern of measured priority. However, the Black wall/White wall principle is still the most important thing to understand.</p>

<p><em>I'll repeat the previous post:</em> The way that flash is controlled, is by how long it stays on (duration), not by the level of light energy that travels outward ... the energy level is always the same. The less light that is needed to meet the meter's set middle grey standard, the shorter the duration of the flash being on. The shorter the duration the more the flash freezes the action.</p>

<p>In darker situations using flash, the camera's shutter speed is always slower than the duration of any TTL speed-light. Always. So you may have a camera shutter speed of 1/100 of a second, but the flash duration may be 1/ 1,000 of a second ... which freezes the foreground subject action.</p>

<p>So, shutter speed has a direct effect on the background exposure, but not on the flash exposure.</p>

<p>Aperture effects both. A lens aperture is like a water faucet ... it allows less light to flow in to the camera when made small (f/16), or more to flow in when made big (f/2.8). Doesn't matter what the source of light is ... ambient or flash ... it is just a "light faucet". How big or small the opening that is needed is determined by the meter standard.</p>

<p> </p>

<blockquote>

<p>Can I use ETTL in conjunction with highspeed sync to freeze motion? Will the resulting image have a black background?</p>

</blockquote>

<p>The short HSS answer is no. The black background answer is yes.</p>

<p>High speed sync is where the speed-light "pulses" the light output in rapid bursts like a stroboscopic effect. However, it is so fast that the human eye/brain can't see it strobing. This technique is used to provide light while the shutter curtain slit travels across the digital sensor at higher shutter speeds. The downside is that each pulse is weaker in effect because it is so short of a duration ... so less over-all illumination makes it back into the camera ... usually resulting in an under-exposed foreground subject when shooting in darker situations.<br>

Plus, if you use a faster shutter speed with HSS flash, like 1/500 (the opposite of dragging the shutter), the background exposure will be darker, or in many cases ... black.</p>

<p>HSS flash is valuable in some brighter conditions for fill flash where you want to use a more open aperture for shallow DOF and need a higher shutter speed than 1/200 or 1/25o to achieve a proper over-all exposure.</p>

<p>It ain't easy is it ... LOL!</p>

 

[ilkka_nissila]

<p><em>The way that flash is controlled, is by how long it stays on (duration), not by the level of light energy that travels outward ... the energy level is always the same. </em></p>

<p>When looking at the flash output curve as a function of time, the total area under the curve is the flash energy and that is what you need to adjust to control how much light is falling on the subject from the point of view of the exposure. The power is the height of the curve as a function of time. If you want to give the subject more light you increase the total area. How the flash implements the increase in area (energy) is up to the flash unit and may not be quite as simple. E.g. to achieve constant output (in terms of the flash energy) in manual mode with short recycle times the flash may extend the duration in order to compensate for limited power. E.g.</p>

<p>http://www.chem.helsinki.fi/~toomas/photo/flash-discharge/redwait.html</p>

<p>As you adjust the flash output you're controlling the energy, not the power. The power varies as a function of time during the flash, and it (and the duration) may vary between individual activation of the flash even with constant flash energy selected on the flash.</p>

[fotografz]

<p>While technically correct in the circumstances illustrated in that report, for a relative lighting newbie, IMO that is just making a confusing concept even more complex and difficult to understand Ilkka. Based on his questions, he is not getting even the basics quite yet ... which in themselves are not easy to understand even though those who do get it think it is simple. I just try to remember back when I didn't grasp something and how all the lingo and variations to a basic concept really made it all the more indecipherable. </p>

<p>In the most basic form, the OP needs to grasp that it is flash duration that allows freezing of action, which is his goal ... and to also grasp that shutter speed is how one can control the background exposure ... which is also a more complex subject than it appears in its most basic form.</p>

<p>- Marc</p>

<p> </p>

[melandkeifspics]

<p>The crazy world of flash.... Now I know why books and workshops are dedicated to this subject in it's entirety. So much to consider and understand.</p>

[dave_wilson1]

When I went to Lois Greenfield's lecture at Hasselblad/Bron Shoot NYC fall 2011, she was specifically explaining how in

the studio with a 1/60th shutter she prefers a flash duration of 1/15,000 or shorter in order to freeze her dancers in mid air

jumps and freeze their clothes etc. She also mentioned how the new Broncolor units can go shorter, I think to 1/20,000, but

Broncolor units are very expensive to bring on a wedding, but, if you needed a very short duration, I think those are the

shortest studio type durations at the most power relatively speaking. You can search all this and get the numbers

specifically and call them too if you had questions.

[Spearhead]

<p>Which Broncolors give 1/15000 or less? I haven't seen them beyond 1/10000, and that's with new packs from 2012. Maybe I've missed something.</p>

[dave_wilson1]

I "guess" the Move 1200L which I assume she had access to as maybe a proto, and uses on location on stages etc. It

goes to 1/20,000

[ilkka_nissila]

<p>1/20000s is the t.5 time for a Move 1200L so quite a lot of the light is still coming from the flash after that time. If you're interested in photographing moving subjects and stopping the movement in the image you probably want to look at the t.1 times instead (in this case, 1/8500s).</p>

[dave_wilson1]

That's an interesting thought Iilkka, and I know you are talking about what some used to call the "staying power". When

we used film, especially print film, it would help give a very through exposure opposed to a small dinky tube. Example, a

Lumedyne 400ws even at 1/4 power (100ws) would have a fairly thorogh emmission, where a Vivtar 283 at full power

(100ws) with it's small straight tube, much less. Also why Amato used to modify the heads and put big round bulbs on

them. However, with reference to your point, with these new modern units which are of the most modern design, I would

just follow the manufacturer rating. Why for example would you want a duration almost 2.3x as long instead of the

1/20,000? IDK what you're thinking is here to be honest, I find it somewhat contraindictory to the cause if you want the

shortest duration. Ok, thank you, I always respect your opinion, you're very knowledgeable.

[tom_bowling1664874721]

I want to go to one of these weddings!

[michaelmowery]

<p>When shooting at these Orthadox or Hasedic jewish halls there is usually alot of ambient tungsten lighting so if you pump up your iso to 4,000 and up you might as well just shoot available light with 200 or faster shutter speeds depending on the focal length of the lens. If you use flash you can not balance the lighting with out causing ghosting in most cases. You must use additional strobes as room lights and lower your iso to around 400 to 800 tops and shoot around f6.3 to f8. The shutter speed should still be as fast as you can make it within syncing. The flash freezes but the shutter will help keep the ambient under control and not cause any ghosting. </p>

[melandkeifspics]

<p>Hi guys... I just shot another jewish wedding and I still didn't nail it. I am including some samples from the wedding and hope to get some more feedback... Should I have lowered my ISO, increased my shutter speed, or increased my f-stop to kill more light? I guess I didn't change my settings drastically enough from the first set of photos I added in my previous post.</p>

<p>Another issue that arises is the amount of acceptable sharpness in my images. My images are not tack sharp. Is that the motion blur I've been trying to overcome or is it handshake? Focusing maybe?</p>

<p>I can still see ghosting in some of my images, although they are not as apparent in each one. </p>

<p>I do have two speedlites now. A 600EXRT which I keep on camera and a 580EXII that I plan to place on a stand somewhere in the reception hall. How should I set it up? What angle? How high? Direct flash or diffused?</p>

<p>I also have two Elinchrom D-Lite-4 with a Skyport trigger, but really wanted to avoid using those due to the setup time and lack of power outlets in the hall. Plus I'm scared of them dropping.</p>

<p>I'm really stressing over this. </p>

<p><img src="http://d6d2h4gfvy8t8.cloudfront.net/17553779-md.jpg" alt="" width="680" height="453" /><img src="http://d6d2h4gfvy8t8.cloudfront.net/17553776-md.jpg" alt="" width="680" height="453" /><img src="http://d6d2h4gfvy8t8.cloudfront.net/17553777-md.jpg" alt="" width="680" height="453" /><img src="http://d6d2h4gfvy8t8.cloudfront.net/17553781-md.jpg" alt="" width="680" height="453" /></p>

<p> </p>

[michaelmowery]

Speed up your shutter to max sync speed. If you are already there then u need to lower your ISO. You are balancing the ambient with

your flash and you are not freezing the ambient light. Large halls require room lights to bring up the background. It would be helpful to

know what your settings were.

[michaelmowery]

<p>let me know what your settings were. I could not see it in the metadata on your files because it was stripped out. Anyways you don't need to lower iso and speed up shutter. You can do one or the other otherwise you are just doubling the effects of stopping down.</p>

[melandkeifspics]

<p>All shots were at 1/100sec and ranged from f5 to f7.1. The first shot was at ISO 3200, the next two at ISO 2500 and yhe last at ISO 3200. The flash power on my flash was set to 1/4 power angled straight up with the gf lightsphere and the ceilings were about 25 feet high.<br>

Lots of ambient light in the hall. Image below was taken without the flash firing at 1/100sec, f/5.6, ISO2000</p>

<p><img src="http://d6d2h4gfvy8t8.cloudfront.net/17554162-md.jpg" alt="" width="680" height="453" /></p>

[michaelmowery]

<p>Shutter speed too slow for this action. First set your shutter to 200 then set aperture to 6.1 and then up your iso till you get a decent exposure not too bright. Last set the power on flash to balance the lighting. 1/4 may be too weak. This type of event requires room lights or cross lighting for best results. Set up at least two flashes on the left and right of the room aimed across the dance floor. Set it to 1/2 stop less than your main light. This will give demension to your shots. I have never done this with a single light and bounced so I can't give you my take on that.</p>