How to do high speed sync using Nikon D750 and Nikon SB-700

<p>I have a Nikon D750 and Nikon SB-700 that I would like to set up high speed sync to use when shooting outside portraits. (Need some fill light). I can't seem to find any info. on it. I would like to use the speed light on my cameral in TTL mode. And I like to shoot in Aperture Priority or Manual modes. Most often Aperture Priority mode.<br>

Can someone help? I have a shoot scheduled tomorrow and would really like to use this set up.<br>

Thanks,<br>

Nancy</p>

<p>Nancy, are you referring to using high shutter speeds with the SB-700 flash, i.e. 1/250, 1/500, 1/1000 sec, etc.? (Keep in mind that the D750's flash sync is 1/200 sec.) For those, you need to use the FP-sync mode.</p>

<p>If you are talking about making a lot of fast, consecutive captures, flash recycle can be an issue. In that case you need to keep the flash power low to conserve energy. Unfortunately, the SB-700 does not have an external high-voltage power jack. (There maybe some third-party workarounds.)</p>

<p>I'm wondering what you're trying to accomplish. If you want to be able to use flash with a large aperture in bright outdoor daylight, the high speed sync does help you use that wider aperture. If the auto FP sync is active in the menu you can just select the shutter speed and aperture that you need. I would recommend working with the camera in manual mode when you're using flash because it gives you more control over the ambient exposure.</p>

<p>Remember that the use of high speed sync results in loss of flash energy in a way proportional to the shutter speed increase. I.e. by selecting 1/500s instead of 1/250s (or 1/400s over 1/200s which I recall is the sync speed of your camera) your flash output is reduced by one stop. This means you cannot use the fast shutter speed (over flash sync) to make the ambient exposure dimmer if your flash is running at its maximum flash energy level (M1/1). But you can take advantage of it for the purpose of shallower depth of field. If you want a lot of depth of field such as you might need in a group shot outdoors then high speed sync doesn't help you really because it reduces the flash output. A larger flash with greater maximum flash energy is then called for. Those flashes may or may not support high speed sync though (so they might not allow the use of wide aperture in bright light within the constraints of a balanced flash and ambient exposure). One way around this problem is to use multiple speedlights and put them in a single CLS group; this way you would be able to increase the output while retaining high speed sync capability. But it is fairly expensive and complicated way to accomplish the result. An alternative is something like a Profoto B1, but that is also very expensive.</p>

<p>Nikon calls High-Speed synch "Auto-FP" mode. This is described on page E-32 of the SB-700 manual.</p>

<p>The main thing needed is to ensure that Auto-FP is setup in your camera's menu. It's found under "Bracketing/Flash" in section e1. The menu option needs to be set to "1/200 s (Auto FP)". If you don't do this then the camera won't force the flash into FP mode (HSS).</p>

<p>After that everything is automatic, but you may have to use S or M mode on the camera so that you can set the shutter speed higher than 1/200th second. In A or P mode the camera may well select a shutter speed of 1/200th second or slower.</p>

<p>Edit: As Ilkka says, using a high shutter speed and flash doesn't gain you any flash-to-ambient ratio. The flash has a fixed maximum power, and using FP synch doesn't alter that. So if the flash can provide, say f/11 at 10 feet with 100 ISO at 1/200th second shutter speed, then raising the shutter speed to 1/400th means you'll have to open the aperture to f/8. So there's no overall gain in ambient-to-flash ratio.</p>

<p>I'm not sure if Nancy is trying to get the same result I am, but I am trying to take a photo of a subject, where I can have the remaining background 'black'/'dark' (invisible black backdrop). Doing a search on the topic, it states to set your camera to 'maximum/optimum sync speed' thus my reason for finding this forum question when doing a search. <br>

I also am using the Nikon D750, with a Yongnuo YN568EX speed light (one of their newest versions) after noting Tony Northrupt of "Stunning digital Photography" mentioned it's a worthy unit for it's price. It works great for general photography, so I would now like to use it to get the invisible black backdrop to use in portraiture, or for other subjects.<br>

I've also picked up a flash ring (LED) and would like to use it in a similar fashion, albeit that may need even more information before I get that to work as above. Thus far, when using the flash ring, it 'looks' to be quite bright if looking at it when the camera shutter is used...but the sync seems to be way off, in that the photo even at close range (using my macro lens) seems very dark??? Appreciate any help/advice on this topic!</p>