Remote flash trigger for NEX-6

[inkista]

Ok. One more clarification.

When we speak of optical triggering with flashes, we can be talking about two different things.

Manfred is speaking of the proprietary near-infrared light-based signaling protocol that most dSLRs come with these days. The built-in commander of which he speaks typically is in the prosumer and up bodies (although there are exceptions. Canon has actually put this kind of commander in the xxxD line of bodies, but the full-frame 5D/6D cameras don't have pop-up flashes so they don't). The problem here is that mirrorless cameras tend to tier downwards from dSLRs. Right now, afaik, there's only one mirrorless camera with a commander built-in and that's the Olympus OM-D. Panasonic doesn't support this kind of protocol in any of its cameras. With Sonys, afaik, only the prosumer Alphas have this.

These proprietary systems, though, rock on the function: TTL, high-speed sync, control over the remote flashes from the camera, etc. Nearly everything you can do with the flash on-camera can be done with the flash off-camera. It just sucks for the expense (TTL gear is generally more complex/expensive than manual-only gear) and when you go outside and on location. Indoors, this can work great, because you have lots of bounce surfaces to mitigate the line of sight requirements and work through/around modifiers. TTL radio triggers can get around this, but typically don't exist outside the Canikon brands, or are very expensive, as in $100 per trigger, and you need one trigger for the camera, and one for each flash you want to use.

The second type of optical slave is what kckunz is talking about. I label this a "dumb" optical slave. All it can do is send the "fire" signal, much like manual radio slaves. Basically, it's a simple sensor that when it sees a flash burst it sends the sync signal. So, you could still use your built-in flash to trigger an off-camera flash. But there are a few caveats here.

TTL is how your camera can automatically set the flash's power output based upon through-the-lens (TTL) metering. The camera tells the flash to send out a burst of light at a known brightness level, meters it, then adjusts the flash power accordingly. So, there are two flash bursts for every image. A lot of these optical triggers are from pre-TTL days, so it's a very simple "see flash burst/fire flash" logic. And the preflash from TTL can trip them early. If you can switch your pop-up from TTL to Manual, then you can avoid this issue. Nikons can do this. Canons, up until a year or two ago, couldn't.

If you're stuck in the forced TTL boat with your pop-up, then you have to find a slave that can fire on the 2nd flash burst, and ignore your pre-flash. And this is assuming you're not trying to use the proprietary wireless signalling--because that's like Morse code with light--multiple preflashes. Also, red-eye settings can send out an addition preflash. So, with P&S cameras and built-in flashes, dumb optical slaves can be tricky.

But this is why I pointed out most of the cheap YN flashes have two built-in dumb optical slave modes: S1 for no pre-flash and S2 for a single preflash. I use a YN-560 off-camera without any additional equipment with my Canon Powershot S90 point and shoot (which has no hotshoe). I set the YN-560 to S1 if my S90 is in M mode. If my S90 is in Av/Tv/P mode, I put the YN-560 in S2. The line of sight thing, though, is much more of a PITA because my P&S's pop-up flash can't swivel. So, the YN-560 can't be anywhere behind the camera. At which point I start doing weird Rube Goldberg things with add-on optical slaves and radio triggers, but I'm an eccentric.

The main limitations with dumb optical slaves include all the ones for smart ones (line of sight, range, reliability outdoors) and add one more: any passing stranger with a P&S camera that has a flash can trip your lights, too. Again, great for use indoors. Outdoors, maybe more of a problem. David Hobby on the Strobist has this great story about how in film days, when optical slaves were commonly used for studio lights (still are actually. A lot of them come with dumb optical slaves built in), someone set up this legendary shoot at an airport, pretty much lighting up an entire arrival terminal, and how a tourist couple passing by got a lot more than they bargained for when they thought to take a snapshot of all the men with big lights setting up a shoot...

[inkista]

Hey, hold the phone. Looks like the $150 HVL-F20AM could be used as an on-camera TTL commander for the HVL-F60M. This would be smart optical.

---
Wait. There's this weird footnote on the Sony site about how it only is a commander with an A900. Crap.
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Ah. On dpreview folks are saying they can use the F20AM as a commander on the NEX7, but that means it's using the Minolta hotshoe. But looks like it's compatible (with a lot of limitations) with a hotshoe adapter.

http://www.sony-mea.com/support/reso...ony/F20AM.html

Hm. No wireless ratios. No wireless HSS... so what does wireless control mean?! Crap, you're gonna need someone who shoots NEX to help you out, here. I can't make heads or tails of it.

[Castor Krieg]

Thanks for trying Kathy! Anyway, I will simply try RF-602 or 603 and see if it works. Since my flash is brand new I doubt there is any danger to triggers from flash voltage. No TTL, but hey, since I already have a flash there is no reason not to use it.

[inkista]

One more note. I'd definitely hit a NEX-centric board of some kind or doing a search on how the RF-602/603s work with the NEX6. Theoretically, there should be no problem. However.

I thought this about micro four-thirds, too, and found there was a weird issue with the hotshoe fit so that RF-602s work just fine (lucky me--this was the trigger I already owned), but the RF-603s do not, and require a rewiring mod to work on, say, an OM-D. Just do a little extra research before you commit to a purchase. This thread on flickr makes me think the 602s might be a better choice than the 603s, since the 602s have dedicated Tx and Rx units, rather than transceivers. [Found a post here from someone who says they use the RF-602s on their NEX6].

Generally speaking, iso-compliant hotshoes should match physical dimensions, and electrically use the center pin for the sync, and the rails for ground, so things should work across systems. But apparently some folks using a NEX6 and the RF-603N (Nikon) find that the transceiver doesn't sense it's on a camera correctly and doesn't switch into transmitter mode. Apparently those TTL pins on the 603s may be doing more than just the wake-up signal they do on the 602s.

[Castor Krieg]

So once more a case when something older is actually better for what you need :-)

[Manfred M]

Manfred is speaking of the proprietary near-infrared light-based signaling protocol that most dSLRs come with these days. The built-in commander of which he speaks typically is in the prosumer and up bodies (although there are exceptions. Canon has actually put this kind of commander in the xxxD line of bodies, but the full-frame 5D/6D cameras don't have pop-up flashes so they don't).

Nikon does not have a flash on the top of the line models (D4, D3, etc.) either, but they do sell an add-on unit to allow the user to use commander mode. I seem to remember Canon does the same.

The reason I've been given for not having a pop-up flash in the top of the line cameras is that this is a possible water ingress point and hence the distinction of water proof for the pro models and water-resistant for the semi-pro bodies.

[revi]

Just a remark about the inverse square rule: it is only valid for a point light source. For a large source (like a light box)
the fall-off is somewhere between inverse linear and inverse square.

[Castor Krieg]

Didn't want to start a new thread - I started playing around with on-camera flash. When the flash is not attached I can freely regulate shutter speed, however the moment I put the flash on (even in M mode) the shutter speed won't go above 1/160. What's up with that?

Also, should I be trying to set flash focal length to mirror that of the lens (so with 50mm full zoomed in with crop 1.5x that's 75mm, correct? the closest value on the flash is 70mm, should I put this in or leave it on auto?). Thanks for help!

[Manfred M]

Didn't want to start a new thread - I started playing around with on-camera flash. When the flash is not attached I can freely regulate shutter speed, however the moment I put the flash on (even in M mode) the shutter speed won't go above 1/160. What's up with that?

Also, should I be trying to set flash focal length to mirror that of the lens (so with 50mm full zoomed in with crop 1.5x that's 75mm, correct? the closest value on the flash is 70mm, should I put this in or leave it on auto?). Thanks for help!

This is related to the maximum synch speed of your shutter. DSLRs and mirrorless cameras use focal plane shutters, that is the reason for what you are seeing. In focal plane shutters, two sets of blades or curtains control the length of the exposures. The first curtain drops and exposes the sensor and when the set exposure time is reached, the second curtain drops and blocks the light hitting the sensor. In extremely fast exposures, the second shutter curtain starts closing before the first curtain has reached the end of its travel.

Unless your camera / flash combination supports high-speed synchronization, you can only do a flash shot when the sensor is completely exposed, otherwise part of the shutter would block part of the sensor while the high speed flash pulse is going off. The fastest speed that this occurs at is your flash synchronization speed. When your camera detects a flash in place, it ensures that a proper exposure can be made and locks out and shutter speeds that are higher than synch speed.

When using off-camera flash, the camera can't tell that you are using a flash and this safeguard is inactive.

[jcuknz]

Didn't want to start a new thread - I started playing around with on-camera flash. When the flash is not attached I can freely regulate shutter speed, however the moment I put the flash on (even in M mode) the shutter speed won't go above 1/160. What's up with that?

Also, should I be trying to set flash focal length to mirror that of the lens (so with 50mm full zoomed in with crop 1.5x that's 75mm, correct? the closest value on the flash is 70mm, should I put this in or leave it on auto?). Thanks for help!

Yes I agree it is a PITB and older cameras let you make mistakes like using a higher shutter speed and only exposing part of the sensor to the flash. The other thing to watch for when using the onboard flash is the shadow the lens may cast on the picture, taking the lenshood off may help here and when using the long end of my 14-140 zoom as here there was no shadow, something one has to work out with one's own gear.

To the original thread question I suspect that when you use the on-board flash to trigger a remote flash the dang thing restricts one to sync speed as well
If you use a wide setting of the flash when using a longer lens you are wasting light illuminating areas outside of what the camera is recording. Vice Versa using a tele setting with a wide lens you will get 'light vignetting' of edges of photo. One of the things I noted when I got my first flash with adjustable beam was the way the rated Guide Number only applies at tele setting so for use with 'normal' and 'wide' lenses the flash was considerably less powerful. Usually the effective angle of view is quoted "for simplicity" and confusion of us all

EDIT PS does anybody know what the creature is? it has lovely long feelers which are seriously cropped in this shot.

[inkista]

Didn't want to start a new thread - I started playing around with on-camera flash. When the flash is not attached I can freely regulate shutter speed, however the moment I put the flash on (even in M mode) the shutter speed won't go above 1/160. What's up with that?

Best article I've seen on sync speed limits and high-speed sync (that mysterious HSS acronym I was slinging around) is this one on neilvn.com. Essentially, the flash burst is faster than most shutter speeds you can use. Your shutter speed is determined by the size of the gap between the 1st and 2nd shutter curtains. As the shutter speed gets faster, the gap gets smaller. Your max. sync speed (1/160s) is when that gap is large enough for the whole sensor to be uncovered as the flash burst goes off.

Once you go faster than that, one or the other (or both) of the curtains will be covering part of the top/bottom of the sensor when the flash burst goes off, and will not be illuminated. There is a feature called high-speed sync (or focal plane sync: HSS or FP mode) where the camera can talk to the flash and tell it to send out very fast pulses of light to keep a steady level of flash illumination for the duration of the shutter speed. But both your camera and your flash have to have this mode built in. Your flash does. Don't know about your camera. Try setting it on the flash and seeing what happens.

One other time-honored way to get around the shutter speed limit if, say you're shooting outdoors in bright light and want to use a thinner DoF, but you can't increase your shutter speed is to cut down the light with neutral density filters on the lens.

Also, should I be trying to set flash focal length to mirror that of the lens (so with 50mm full zoomed in with crop 1.5x that's 75mm, correct? the closest value on the flash is 70mm, should I put this in or leave it on auto?). Thanks for help!

A lot of flashes these days can automatically take the crop factor into account. The manual for yours says it does on page 41. But basically, all the zoom on the flash is doing is moving the tube in the head closer to or farther from that front panel. The farther back it is into the head, the narrower and more concentrated the coverage of the flash's beam, and the farther the light can travel. The closer it is, the broader the coverage. The focal length is just to approximate the FoV of a given lens on the camera, so you won't be wasting power by throwing it where the lens can't see it. But if you wanted a spotlight effect, you could also zoom tighter than the lens you're actually using (or use a grid. Or a snoot.. or...)

[Castor Krieg]

Yes, the HVL-F60M has HSS option, but I need to look and check if NEX-6 supports one. If not - one more feature of flash I won't use, probably until I learn more about photography and get a proper full-frame DSLR a few years down the road. Once again thanks a lot for all the helpful information.

Found this post:

http://www.flickr.com/groups/h550/di...7632828434734/

It seems to mention that NEX-6 supports HSS, I am unsure if he had the flash mounted or did something else to make it fire. Will play with the settings he mentioned and see if they work.

[Manfred M]

Yes, the HVL-F60M has HSS option, but I need to look and check if NEX-6 supports one. If not - one more feature of flash I won't use, probably until I learn more about photography and get a proper full-frame DSLR a few years down the road. Once again thanks a lot for all the helpful information.

Found this post:

http://www.flickr.com/groups/h550/di...7632828434734/

It seems to mention that NEX-6 supports HSS, I am unsure if he had the flash mounted or did something else to make it fire. Will play with the settings he mentioned and see if they work.

As with anything, there are advantages and disadvantages to HSS.

Advantages - Works at any shutter speed, even the fastest shutter speed that your camera has.

Disadvantages

1. Does not put out as much light as a traditional flash. You lose at least one stop.

2. Needs special flash units to work. So far as I know, only proprietary units made by the camera manufacturers have this functionality.

3. Cannot use creative techniques that rely on a combination of ambient and flash illumination, "dragging the shutter", front & rear curtain techniques, balancing the exterior and interior lighting in an interior architectural shot, etc. While I won't say I use these techniques all the time, but I do use them regularly, far more in fact than HSS.

[tclune]

2. Needs special flash units to work. So far as I know, only proprietary units made by the camera manufacturers have this functionality.

The Yongnou 568EX flash supports HSS, at least on Canons and Nikons (where it is called Auto FP for some obscure reason.)

[inkista]

Found this post:

http://www.flickr.com/groups/h550/di...7632828434734/

It seems to mention that NEX-6 supports HSS...

Actually, from a quick glance at that I don't think that's HSS. That's another sorta-similar-but-not-really feature that PocketWizard calls "hypersync", Yongnuo calls "supersync" and those of us weird enough to care will generically label as "tail sync".

It's FAR more inefficient than HSS power-wise. And afaik (I'm not that savvy on the details), it goes kind of like this. Flash "power" is kind of a misnomer. The power level on your flash is actually a matter of the flash burst duration. The higher the power, the longer your flash tube is turned on. So, at full power, your flash's burst might actually be longer than your highest shutter speed. The problem is the power, as it dumps out, isn't particularly even. There's a huge amount at the beginning, then the power/light tails off more evenly.

So, a manual flash/studio strobe is set to full power, then fired early, and the shutter is open during the tail. The effect is rather like HSS: you can use a higher shutter speed but chances of a light falloff over the frame are higher than with HSS, and you have a very narrow window of opportunity where the flash pulse and your shutter speed are going to coincide. Typically, any power setting other than full power won't work with this.

I think RadioPopper were the first ones to crack the max. sync speed limit with studio strobes this way. Then PocketWizard included it in their TTL triggers. Now all the cheapie TTL triggers are doing it. I tested this feature with my YN-622c and my 580EX and it works fine with that combo. With my YN-560 (which is the one where I really wanted it to work) it was a no-go. [sigh].

As with anything, there are advantages and disadvantages to HSS.... You lose at least one stop....

Actually, van Niekerk says it's two stops, and from his testing and my personal experience, I'd agree.

...So far as I know, only proprietary units made by the camera manufacturers have this functionality.

Actually, the 3rd parties have been coming up with this in the last year or two. The Metz 58, Nissin Di-866 (and I think the Di-622, but not sure on that), and the Yongnuo YN-568EX and upcoming YN-500EX all have HSS capability.

... Cannot use creative techniques that rely on a combination of ambient and flash illumination, "dragging the shutter", front & rear curtain techniques, balancing the exterior and interior lighting in an interior architectural shot, etc. While I won't say I use these techniques all the time, but I do use them regularly, far more in fact than HSS.

For me, I typically use 2nd curtain about as often as I use HSS. Both are relatively rare usages for me, but when I need them and don't have them, I curse. A lot.

But as for balancing ambient against flash, well... if you use TTL, and you've got the headspace on exposure, you could "drag" your iso instead.

The Yongnou 568EX flash supports HSS, at least on Canons and Nikons (where it is called Auto FP for some obscure reason.)

FP = Focal Plane. FP is actually the terminology for HSS for Nikon, Pentax, Olympus, and Panasonic, so it's not just a Canon/Nikon thang.

[inkista]

One more note for Castor:

Most of us don't find the sync speed limit that big of a deal unless we want a narrow DoF in bright light and need to compensate for a large aperture. For freezing motion, we don't use the shutter speed: we use the flash burst.

Remember how I said that normally the flash burst is faster than your shutter speed? If my 580EX is on 1/16 power, then the duration of the flash pulse is around 1/15000s. See? Fast.

So anything that's lit only by the flash will be frozen, even if the shutter speed is 10 seconds long. It's only the ambient-lit stuff that will be motion-blurred. You might still get some "echo" movement blur where the ambient and flash overlap, but if the ambient lighting is relatively low, the flash lit portion of the scene will be frozen.

[jcuknz]

The Yongnou 568EX flash supports HSS, at least on Canons and Nikons (where it is called Auto FP for some obscure reason.)

I maybe behind the times but with the 468 YN you need to get the Canon version OR the Nikon version to suit your camera.
Probably the name difference is for copyright reasons.

[inkista]

I maybe behind the times but with the 468 YN you need to get the Canon version OR the Nikon version to suit your camera.
Probably the name difference is for copyright reasons.

Actually, no. It's a different model. Yongnuo models proliferate like mad. They seem to come up with a new one every four months, if they're not renaming older models or spinning roman numeral revs. Speedlights.net was an awesome resource to track all this stuff, but they seem to have stopped updating the site about a year ago, so newer stuff like the YN-622c and YN-568EX aren't reviewed. Flash Havoc and Lighting Rumors might be the sources to go for, now.

The YN-468 does eTTL/iTTL, but doesn't do proprietary wireless slave (CLS/wireless eTTL) or HSS. And yes, you need the appropriate version, and they only come in Canikon flavors afaik. The Canon and Nikon hotshoes have different pin/contact placement, so you need to get a version that physically matches the hotshoe you're using if you want any TTL capability.

Weirdly, though, the wireless slave function in the 565EX and 568EX are system-agnostic, apparently. If you get a Canon one, you can supposedly still slave it via CLS to a Nikon commander unit.

BTW, from what I've read, with the new YN-568EX, the Canon version has silver lettering on it, the Nikon version has gold lettering.