Brooke Eaton , Jun 26, 2009; 12:42 p.m.
I'm in need of some help. Ive rented a Nikon D700 and a SB 800 flash. I've been outside, in full sun, trying to use the flash as a fill. I have it set on TTL ISO 100. 50mm F 2.8. All of the photos are blown out. How can I fix this?
Nadine Ohara - SF Bay Area/CA 
, Jun 26, 2009; 12:46 p.m.
What are the settings? Full sun = ISO 100, f11, 1/250th or equivalent. If you are not at or near those settings, you are just overexposing, period, and the flash has nothing to do with it. If you are at those settings, use your flash compensation control to ramp the flash back.
William T. , Jun 26, 2009; 01:03 p.m.
On top of what Nadine's suggested you might also want to switch it from TTL to TTL-BL.
Robert Gulotta , Jun 26, 2009; 01:33 p.m.
if you are in aperture priority, the D700 should also be set to high speed sync, somewhere in the custom settings. If not, you are going to max out at 1/320 or 1/250, causing a lot of overexposure unless you are set at f/11 or smaller.
Nadine Ohara - SF Bay Area/CA , Jun 26, 2009; 01:37 p.m.
And keep in mind that High Speed Sync cuts your flash power, so outside in bright sun, you will have to stay pretty close to your subjects or the flash will not reach them. Might do well to research bright sun flash fill if you are practicing for an upcoming wedding in bright sun.
Brooke Eaton , Jun 26, 2009; 01:44 p.m.
robert,
I have noticed that it is maxing out around 1/250. Im shooting in M mode though.
Brooke Eaton , Jun 26, 2009; 01:49 p.m.
I've never used high speed sync before.
William Porter , Jun 26, 2009; 01:52 p.m.
Brooke,
For starters, it sounds like you should take a test shot or two and review them on the camera's review screen, check the histogram or (my preference) use the camera's feature that causes blown highlights to blink, so you can see how you're doing. You say "all the photos are blown out," but I think you should be able to prevent that by reviewing a couple. If you take a shot or two and everything's obviously overexposed on the review screen, well, you know you need to do something different.
I'm pretty sure the problem is simply that you were using f/2.8 - and probably unable to shoot faster than 1/250th sec (which I assume is the sync speed for the D700). As Nadine said, the flash probably had nothing to do with it. Your photos would have been overexposed without the flash.
Nadine mentions a version of the "sunny sixteen" rule of thumb, which says that, in full sun, you'll get a correct exposure (or something close to correct) if you set the aperture to f/16 and set the shutter speed to the ISO, so for example: f/16 + ISO 100 + 1/100th sec, or f/16 + ISO 250 + 1/250th sec. Nadine's suggested settings - f/11 + ISO 100 + 1/250th sec - are simply a variant of the "sunny sixteen" rule: she's opened the aperture one stop and offset that by (roughly) doubling the shutter speed, while leaving the ISO at 100.
Give the sunny sixteen rule of thumb, if ISO = 100 and aperture = f/2.8 (five stops wider than f/16), the shutter speed would have to be 1/3200th sec or faster (five stops faster than 1/100th sec). THAT IS WITHOUT FLASH. But you can't shoot faster than 1/250th sec because that's the camera's flash sync speed. So, either you stop the aperture down a LOT - or consider switching to high-speed sync. High-speed sync may help you use a bigger aperture.
Basic idea for using fill flash in sunlight: start with as correct an exposure as you can get using natural light, with the flash turned off. Then add the flash. Results are often subtle. Full sunlight's hard to compete with.
Will
William Porter , Jun 26, 2009; 02:03 p.m.
Brooke, the way you say "I've noticed that it is maxing out around 1/250" indicates that you might want to read a little more about flash basics, so you know what "sync speed" is as a general matter and what the specific sync speed is for the camera you're using, as well as the ways that changing aperture and shutter speed affect exposure when you're using flash.
I'd suggest skipping high-speed sync for the moment, doing a little reading, and then spend some time testing. Just about the best thing about digital photography is that it costs virtually nothing to practice. And it's fun, too!
Will
Douglas Lee 
, Jun 26, 2009; 02:11 p.m.
robert, I have noticed that it is maxing out around 1/250. Im shooting in M mode though.
Yes, that is the max flash sync speed on the D700 (1/320 is a holdever from the F5), unless you enable high speed sync. If you just want to point and shoot, try setting the D700 to P mode and the flash to TTL BL mode. If the flash is set to TTL, it will assume it is the primary light source, so you may have to play around with some negative flash exposure compensation to get a more pleasing look. Good luck and enjoy.
