It's been a long time since I shot a wedding, but I'll offer you my advice. Keep in mind that free advice is often worth what you paid for it...
In manual mode on the 2600, the flash output is always the same, with exposure changed by adjusting the aperture on the lens, based on the subject distance. Flash output remains the same, aperture changes. In the blue or red auto settings, it's the other way around; flash output varies, aperture (within the selected auto range) stays the same.The flash is basing its exposure on reflected flash illumination from the subject as read by the sensor built into it. The flash will tailor its output based on the sensor reading. This is strongly dependent on subject to camera distance (actually subject to flash distance, but when the flash is on the camera these distances are the same). A closer subject will reflect more light than a distant one, so the closer subject results in a faster flash cut-off than a more distant one.
If you're not good at guestimating camera to subject distance by eyeballing, the lenses you'll be using on your ME Super are likely to have actual focus distance scales on them. You can check that for the distance. This is easier to do with posed group shots where nobody is moving. Candid shots where either you or your subjects are in motion might not offer enough time to let you consult the distance scale on the lens. Try to get a feel for where the changeover from the blue to the red auto setting takes place. Before the wedding, find a friend you can use to try to figure out a way of gauging distance through subject size. Measure out 15 feet between your friend and your camera and see how big they appear in the viewfinder. So, if people of similar height to your test subject appear smaller in the viewfinder than your friend did, they will be more than 15 feet away and you should switch to f4 and the red auto flash setting. Do this for any and all lenses you're going to use. If you're using a zoom lens, do the same thing for each end of its focal length range.
What lens or lenses are you using? If you're using a 50mm lens, chances are very high that most of your shots are going to be within 15 feet of your subjects, unless you're shooting large groups of people. I would also recommend shooting a test roll before the wedding to practice your technique and evaluate your results. Try to test under conditions as close as possible to what you'll be dealing with on the big day. You don't want to have to learn on the job when you're shooting someone's wedding.
An added note: A white wedding dress can cause a slight chance of underexposure as the flash sensor performance is based on the assumption of an overall middle grey tonal value subject. A lot of white in the scene will reflect more light, which the sensor will interpret as correct exposure of something it assumes is grey. In that instance the white dress will be grey in the shot and everything else will be underexposed too. You might get around this by either opening the lens up to an aperture a bit larger than the recommended one OR by selecting a slightly lower ISO setting on the flash. I'm not sure by how much you would need to stray from the suggested settings. Perhaps others here can chime in on that aspect. I used to shoot Ilford so I'm not sure how forgiving Tri-x is with under or overexposure. Again, someone else here might offer more precise suggestions in this regard.
Good luck!
Last edited by Thagomizer; 11-03-2017 at 04:28 PM.
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