Hi Robbi, For a quick fix you could try turning your 550EX into a TTL machine. There's a CF on the flashgun to do this. In addition to the camera's sensor being sensitive to the brightness of your subject, I've found my EOS3 / 550EX quite susceptible to specular reflection from shiny fabric fibres etc., and these reflections (visible on the slide under a microscope) seem to be able to throw the exposure off. TTL using reflections off the film itself probably isn't affected nearly so much. Guess it's to do with a direct optical path (in E-TTL) from the shiny fibre to the sensor, with no diffusion. (I'm open to other suggestions, but only if people have viewed their slides critically as I've done <g>.)
The following is a quote from what I sent on this subject a few days ago. " There's still a slight tendency to under-exposure if the flash is on the camera, and your subject is wearing shiny fabric. Getting the flash(es) away from the camera, say by use of an ST-E2, improves the exposure reliability no end, in my experience. I know many people blame it all on the whiteness of wedding dresses etc. and this certainly is a factor, but I've carried out tests using specially purchased light coloured shiny fabric. Tripod mounted camera position and fabric samples didn't change. Lighting did. Best results were with flashes bounced into reflecting brollies away from the camera, and at about 45 deg. Nicely exposed and good to look at. Flash on camera - 1/2 to 2/3 stop under-exposure, and rather harsh. Check on slide through microscope, and you can see the direct reflection of the flash in the fabric fibres." Malcolm Milton Keynes, UK ----- Original Message ----- From: robbi pengelly <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, June 15, 2002 5:32 PM Subject: EOS D30 with 550EX - Help! > > > I know I've come to the right place but I should warn you, this might be > a really stupid question. Technically savvy, I'm not. > > I'm using a D30 with the 550EX, and I'm having a terrible time with > ETTL. For years, I used a 1N with the 540EZ, had no problem at all. I > knew that flash's capability fairly well and could get exactly the right > amount of light out of it. * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
