Well, it's not exactly good news, but at least I finally have an answer.
One year ago, my bosses enabled me to buy a new camera for work because the one I'd been using was damaged (but still operable with duct tape) during our office move. I've been fighting that new little camera for about eight months now because it can trigger slave lights, but it doesn't synch with them. Everything with slave lights comes out under-exposed, no matter what I do.
Too technical for the average reader, right?
Photo of Me and the New Little Camera courtesy of Mrs. Micawber
Some of the answer is beyond my expertise, too. Months of wild goose chase research proved someone somewhere needs to explain the problem and solution, because I sure couldn't find an internet answer! So I'm doing my best to detail symptoms and my personal cure so others who might be in the same quandry might be able to discover a solution that might work for them.
For more than a decade, I used an old manual film Nikon with a couple of inexpensive slave lights triggered by the best strobe money could buy back in the late '80s/early '90s for miscellaneous office photography. I surrendered to digital in about 2004 when I learned Kodak would no longer be making film cameras.
I bought a couple of different low-end digital Fuji cameras to see if digital photography and I could co-exist. After learning to work around the limitations of early low-end digital cameras (shutter delays, absense of manual controls, worthless manual focus, etc.), I wasn't being dragged kicking and screaming into modern technology anymore.
The Fuji cameras worked just fine with my little slave lights, which are now going on 20 years old. Slave lights are camera flashes mounted on tripods (or set on tables or held in place by trustworthy assistants such as The Lizard). They light up when they see the light of an on-board camera flash (the pop-up flash on top of most digital cameras), extending the power of flash further than 2 to 12 feet, but also eliminating non-flattering shadows created by in-your-face flash.
Unfortunately, my big step into genuine digital photography in 2008, my Nikon D300 (aka: "The Big Gun"), could not trigger slaves.
Gone were shutter delays and permanent auto pilot, but I had to save up for a pair of pricey Nikon strobes for big shoots (magazine and advertising shots for occassional work-related requests, senior and family portraits and weddings on the side). I learned the hard way, on such a big shoot, the D300 cannot fire slaves or even the now 30-year-old professional-grade Metz side-mount strobe. My "big gun" is built to computer command fancy-schmancy compatible Nikon strobes with more settings than a television remote. The single-setting on/off little slaves, however, still worked sufficiently with the Fuji cameras for inch-high intranet photos.
Until one Fuji gave up the ghost the day after its warranty expired and the lone surviving Fuji got dropped years later during the office moving process.
Bump, bump, bump, another bites the dust.
Research, research, research, followed by a gift certificate from my bosses at work last Christmas resulted in me picking the Nikon P510 on January 31, 2013, because:
1. No shutter delay. (in theory... it actually does have a delay, sometimes annoyingly long)
2. Manual control.
3. No interchangable lenses, which means dust can't get on the sensor.
4. Nice zoom.
5. MOVIES, too?!? WOWIE!!!
6. Small, lightweight and Ride-the-Rockies portable.
What I didn't know and what the salespeople couldn't really answer was whether this new little camera could adequately do night photography.
I had to experiment. Not a serious problem in my neck of the plains-meet-foothills. I like to play with photography, so I put the new camera to the test all summer, with fireworks, lightning and glow-in-the-dark snowflakes.
The P510 can't beat the D300 in any department, but it beats the heck out of the Fuji cameras in all respects with the exception of triggering slaves. I considered the new little Nikon a worthwhile investment.
I took the little camera on Ride the Rockies last June. I fell even more in love with it. Good thing the heavy D300 doesn't get jealous. Plus, now I have a good working camera when the D300 must be turned in for servicing or cleaning.
However, the new little Nikon cannot fire Nikon-specific strobes. Go figure. No command mode. At all.
The built-in flash triggers my generic dinosaur slaves, but the camera won't synch, even at a slow shutter speed. This means the slaves fire like they are supposed to, but they don't light up the picture. Why?!?!?!?!?!?
I researched until my head hurt. I tried everything I could think of. I used recommendations of working pros. I used all-manual settings. I slowed down the shutter speed. I slowed the shutter speed so much, I caught motion. I opened the aperture. I used rear-curtain and delayed-synch features built into the little Nikon.
Still, every studio-type shot was underexposed.
Programmed Mode, 50th of a second, with slaves
After poring over Nikon literature, forums and reviews, I finally took the camera and one of the little slaves to my favorite camera shop, where I had purchased it 11 months earlier. "Help!" I cried! Salesmen jumped straightaway into service. It was refreshing to watch them re-invent the wheel, trying to duplicate the problem I was experiencing, attempting everything I'd already done for six months, in an effort to prove what I already know: slaves don't work with this particular camera model. (Duh.)
As it turns out, the P510 was not built to accommodate external flashes or slaves. Period. A question I simply did not know to ask one year ago.
What the salespeople couldn't understand is why photos with slave come out under-exposed. They said they will be chewing on that mystery for months until they can figure it out. The photos should be over-exposed, they said, because the camera was set to manual and cannot compensate for extra light in that mode. The extra light the slave is throwing out should brighten the scene. In manual mode, camera settings shouldn't be changing.
Yet, the camera does compensate. The compensation doesn't show in the camera or photo readings, but photos with slaves ARE darker. More light available; less light allowed through the lens. It doesn't make sense.
Manual Mode, 30th of a second, with slaves
I didn't want to buy another camera just to be able to use my old slaves. I definitely got my money's worth and more out of those cheap little units.
I wanted slaves or flashes that will work with this camera. The salespeople shook their heads.
No can do.
However, they said, I can buy continuous studio LED lights (which means less electricity, no flash, the lights stay on until they are turned off) for less than the cost of one Nikon-specific strobe. Continuous studio lights will work with all my cameras, even the iPhone, and I won't have to struggle with trying to get the slaves to work anymore.
I can't take studio lights on Ride the Rockies, obviously, and I likely will need a set for home at some point.
Not the answer I wanted, but at least now I know. I'm not going crazy. The camera isn't malfunctioning. Even the aged slaves are not broken.
Everything is doing what it is designed to do, with the exception of the camera's stubborn compensation. This old dog has learned new technology. Again.
Umbrella lights, here I come!
Programmed Mode, 50th of a second, continuous umbrella lights, no flash
UPDATE: Because most of my blog posts are set up to automatically publish up to four weeks in advance, due to my issues with unreliable internet access, this post was written before the new studio lights arrived. They're here now, I've tested them, and I LOVE them! I will be saving up for a set for home now! They still won't go with me on Ride the Rockies, but they will be so much better than blinding flashes and strobes that often don't last longer than their warranties!