BASIC FILL FLASH 

THE START: KNOW WHERE YOU ARE

1- Meter and determine the average ambient light you are shooting in, either with or without a good light meter. You can use the cameras meter as long as you know what you are doing. They are inexpensive enough to afford and may I suggest pawn-shops. What you will find is the pawnbroker is very happy to get rid of it.

2- Break the ambient light down to whether it is low, shade, cloudy etc. medium, average partial sunlight, or high, extreme back-lite or beach, really bright day. Simple enough, to evaluate where you need to be with a flash setting to correlate with the existing ambient light.

3- In low light the flash will take over the scene and might be the only light on the subject. 

4- In Medium or average light the flash and the ambient light will have to be on the same page, or one or the other will have to be selected to overpower the other.

5- In high ambient light conditions such as the beach and backlight shooting into the sun the image will overpowered, so we add sufficient flash to brighten the shadows on the subject.  On extreme backlighting full manual power might be needed to accomplish this. 

FILL FLASH HINTS FROM NIKON: 
Auto FP High Speed Sync is a flash mode used for fill-flash photography under brightly lit conditions. It will fill in and open up shadowed areas in order to portray the greatest detail in subjects. It's also ideal when using wide aperture lenses, and because it allows fast shutter speeds—up to fastest shutter speeds on compatible Nikon D-SLRs.  

It is often used for action-stopping sports photography. And for portraits, you can open up your lenses to their full aperture in order to isolate your subject against a blurred background without overexposing the image.  When Auto FP High Speed Sync is selected, the flash will fire for the duration of the shutter curtain's travel, thus syncing with the camera's shutter speed when that speed is set higher than the camera's normal sync speed.  The power of the flash must be adjusted to balance with the ambient light to make the subject equal brightness to the background ambient.  This is the purpose of the ITTL-BL mode and the FP mode under really harsh light. 

CUSTOMER SUBMITTED QUESTIONS and TIPS:
Thanks to:  James "Spice" Williams, Creative Director, Eclipse Photography & Design

(Email) We know about nightmare shooting on the beach here, James, I live two miles from the recently renamed "Gulf of Halliburton". You are faced with strong ambient light amplified by the sand and water especially in the Pensacola area where the sand is literally 92 grade white. That is if they survive the oil. We'll try several ideas putting our minds together.  

PROBLEM:    HIGH SPEED SYNCH INOPERABLE
LOCATION:  BEACH SUPER BRIGHT

SOLUTION:  MOVE FLASH OFF CAMERA CLOSER TO SUBJECT  

The problem is to get the flash to retain its power closer to the individual, away from the camera and guess what, the transmitter method even with Pocket wizards will not function under high sync mode. The Wizards and others don't or do not carry the signals for the Hi-Sync.  The SC-17 cable is not capable of that signal either, perhaps a SC-27 cut and splice could carry it. It requires a manual connection.

ALS ANSWER:  ZEBRA CABLE  Has a I-ttl late version Nikon aftermarket cable with fairly good metal findings (end modules)  in a 24 foot cable that saved the day and made this a simple project. 

(Email) 

Reply to Al Jacobs,
I just wanted to say thank you.  I emailed you because I had a problem with high speed sync on the beach. Thanks for trouble shooting the situation and hooking me up with zebracable.com. I had a couple of SC17 cords and tried them out but to no avail.  I thought you should know before you make these cords for someone and they don't work at that distance.  When you increase your shutter speed in the high sync mode it reduces your flash output to the point of USELESS.  What a manufacture rip off.  I have found two options to shoot on the beach on a sunny f/16 day.

Solution one - Expensive

High output expensive studio lights or a camera with electronic shutters.  

Solution two

Nikon D70, D40, Canon G10, G11 and Sony R1 are examples. I have not tested the Canon G's but I think this will be the winner for me. My wife thinks I'm crazy but if I can get an additional beach session in a day, that translates to more money. That she understands.  The rest is up to guys like you and I. I wish you well my friend.  Thanks again for all your help.  

James "Spice" Williams