Thanks for the helpful replies... In response to Stanley who wrote: >Wait a minute, pilgrim! Before you tell Nikon to wake up I think you need >to let us know if your SB28 is set to full-flash mode or fill-flash mode. >If you are full-flash mode then the SB28 is the primary source of light and >it should not be underexposing if it is working properly and being used >properly...etc. I understand the difference between Fill Flash and Key Flash where the flash is my key light source.. (as you said flash 101). However, when I use the SB28 with F5 and AF/D lens in the TTL Auto Flash Mode (3D Multi-Sensor Balanced Fill-Flash) it SHOULD always provide a correct exposure. I mean if the ambient light is stronger - then the fill flash will be weaker, if the ambient light is much darker then the fill-flash becomes stronger and eventually takes over as the main light source on the SB28. Nikon themselves say, and I quote page 109 of the F5 instruction booklet "TTL Auto Flash (Automatic Balanced Fill-Flash) is recommended for MOST FLASH SHOOTING CONDITIONS since flash output is automatically compensated to balance the ambient light exposure setting. What I am getting at is that the only real difference between Fill-Flash and "Full-Flash" as you put it, is whether or not the BACKGROUND is correctly exposed or to quote Nikon again "This means that, even though the main subject is correctly exposed, the background may not be." However, my gripe is that the main subject (even in macro work with SC17 cord taking the flash off-camera) is frequently underexposed when I use the SB28 in TTL Auto Flash Mode. I would like to add that I have used flash with Canon, Pentax, Nikonos underwater and Nikon systems for 22 years with great success. Thanks again John van Zijl