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Since the sensor on a remote slave flash is triggered by the flash built into the camera do you still have problems with the internal camera flash causing haze, fog, smoke, droplets, etc. to show up photographs? And yes, I'm new at caring about photography(with respect to my group) and I'm getting ready to invest in a cheap slave.

Yes, often it can. Some cameras (even point-and-shoots) have to option to adjust the intensity of the built in flash. When using my little Canon A540, I usually turn the flash down to 1/3 or 2/3 power, but at 1/3 it isn't quite enough to trigger my cheapest little slave flash unless it's close to the camera. You can also use a little piece of white electrical tape or similar to diffuse the camera flash, or a piece of processed slide film to create a simple IR flash filter.

Or if your camera has a hot shoe (like my Olympus C5050), you can get a little flashgun with a bounce head. Simply point it up at the ceiling (or at a wall) and it should still trigger the slave without affecting your picture. Hope this helps.

Or don't bother with optical slaves at all- go straight to radio, the cactus ones dicussed previously
http://www.forums.caves.org/viewtopic.php?f=4&t=8655 are actually cheaper then many optical slave options.
If you're dealing with a built in flash with no hot-shoe there is a work around, it's a bit of a kludge but it works- use an optical slave (the wein peanut ones are fairly cheap) to trigger the radio trigger which will trigger your slaves. This way you can block the built in flash and you'll still reliably trigger your slaves that are a distance away.

Take care that your built in flash doesn't pre-flash and set off the slaves prematurely.

ArCaver wrote:Take care that your built in flash doesn't pre-flash and set off the slaves prematurely.

Very true. Suggest either finding an optical slave which ignores the pre-flash(es), or using an external flashgun which recharges instantly (the ones with adjustable power settings often do when set to low power). Or go with RF slave triggers like captnemo suggested. I use options 2 and 3, and/or set my camera not to pre-flash.

That built-in flash can play havoc with photos, causing red eye or haze, and washing out the nice shadows made by your off-camera flashes. At the least, turn it down as suggested. If you have a hotshoe, I recommend the Wein flash trigger which is infrared and does a great job. It emits no visible flash. It's very small as well and runs about 60 bucks, runs off a hotshoe like a regular flash.

Dave Bunnell wrote:That built-in flash can play havoc with photos, causing red eye or haze, and washing out the nice shadows made by your off-camera flashes. At the least, turn it down as suggested. If you have a hotshoe, I recommend the Wein flash trigger which is infrared and does a great job. It emits no visible flash. It's very small as well and runs about 60 bucks, runs off a hotshoe like a regular flash.

Sounds to me like I need to buy a camera with a hot shoe. I assume any remote slave flashes can be triggered with an item like the "Wein flash trigger". That being said if I was going to spend the money on the whole package would I be better to go with an RF trigger or stick with IR?

You could mount your camera on a tripod, disable the on-camera flash, and use the short timer/self timer, along with 2-4 second shutter speed, to trigger your flashes manually.

A light tripod for a light digicam is really cheap- I've got a K-Mart tripod that has lasted for years- telescopes out to about 48", collapses to about 12", and cost me $5 on closeout. It'd hop around like a jumping spider if I put my Nikon F2A on it, but for a small camera, it is ideal.

The tripod forces you into spending some time looking at the scene you want to shoot. And helps to minimize the opportunities for dropping the camera(been there done that) or slipping and falling while framing the shot(BTDTx2). ;-)

I've used optical triggers for several years- the main reason being cost, the most common RF triggers (pocket wizards) will cost you around $100-$200 apiece and you need one for a trigger and one for every flash unit you use, that can add up fast.
Now that I've found the cactus v4's and can get a transmitter with receiver for $45, RF is definitely my preferred way to go.
That said the cactus isn't perfect- they're made out of cheap plastic and I've had to open a couple of the receiver units up to bend the battery contacts back so they make good contact (if you leave the batteries in while carrying them on a really bumpy road the contacts get loose). They still work though so thats a good thing.

few advantages of RF,
1. no one else will trigger your flashes, In a large group this is very useful(there are lots of different channels so even other rf users should be safe)
2. Typically larger range then optical triggers - 90' and can be expanded with another trigger receiver set.
3.You can place your slaves around corners and out of sight, they'll still trigger.
4. They work in broad daylight (not really a benefit in a cave but nice to know if you use fill flash outdoors)

John Lovaas wrote:You could mount your camera on a tripod, disable the on-camera flash, and use the short timer/self timer, along with 2-4 second shutter speed, to trigger your flashes manually.

Tripods are a good idea, and I also have a smaller/lighter folding model which is good for caving. That said, every piece of caving gear adds up in weight and bulk and I repeatedly make excuses not to carry a tripod with me. Plus I take some damn good photos hand held.

captnemo wrote:I've used optical triggers for several years-

Now that I've found the cactus v4's and can get a transmitter with receiver for $45, RF is definitely my preferred way to go.

I've also used optical triggers for years, and recently added RF ones to my arsenal. Mine are cheap versions too - Fotodiox brand. Got a set with 1 transmitter and 2 receivers lightly used on eBay for about $25. I recently tested the (line of sight) maximum range to 180 feet, but of course this is less around corners. These are single channel and cheap construction, but I took them apart and replaced the cords/connectors and made them a little more rugged.

I agree with your RF advantage list, except that my Gibson kitset optical slaves (similar to the original firefly but much cheaper) have an impressive range of up to 1/4 mile and a hair trigger of 3.5% above ambient light. The even work well around corners! I usually carry both RF and optical with me now, and if I want long range I choose optical.

One more advantage of RF. My own optical triggers and some other models are prone to false flashing caused by the pulse-width modulated regulating circuits in some LED headlamps - especially home built ones. This can be really annoying!

NZcaver wrote:

John Lovaas wrote:You could mount your camera on a tripod, disable the on-camera flash, and use the short timer/self timer, along with 2-4 second shutter speed, to trigger your flashes manually.

Tripods are a good idea, and I also have a smaller/lighter folding model which is good for caving. That said, every piece of caving gear adds up in weight and bulk and I repeatedly make excuses not to carry a tripod with me. Plus I take some damn good photos hand held.

I also, often decide not to carry a tripod since it takes up extra space/weight and time to set up. I've had a lot of luck with one of these- http://www.amazon.com/Pod-Bean-Portable-Support-Camera/dp/B000FU774C It's a little beanbag that attaches to the tripod mount on the camera. It's small/ lightweight quick to setup and I no longer worry about my camera getting muddy when I set it down on a rock. It won't support a long lens but I don't usually take my 400mm tele in the cave with me

I'm no expert, but I've heard of people taping some red cellophane over their camera flash, so that the flash itself does not affect the photo (mist reflection etc) but it still triggers the slaves, which apparently only need to pick up a certain wavelength to trigger. True, or bullcrap?

John Lovaas wrote:You could mount your camera on a tripod, disable the on-camera flash, and use the short timer/self timer, along with 2-4 second shutter speed, to trigger your flashes manually.

Good suggestion John. I also use the successive shot feature where the camera can be set to take X number of shots with X seconds between them, more cameras are coming out with this feature, some are set to only 3 shots with 10 seconds in between. This is good for trying different flash setups.

I like to use the built-in flash, at its low settings and diffused, to signal those on-flash to start firing.

I block all the light from the on-camera flash, and use fiber optics to point the light towards the slave strobe. You could also use a small mirror.

NZcaver wrote:I repeatedly make excuses not to carry a tripod with me

captnemo wrote:I also, often decide not to carry a tripod since it takes up extra space/weight and time to set up.

Me too, but then I get to a spot where I say, “DANG! I wish I brought my tripod!”

FW wrote:... use fiber optics to point the light towards the slave strobe. You could also use a small mirror.

I think that's a good setup for underwater cases but not too practical where multiple slaves are 10 or more meters from the camera.