L358, how to connect?

[Harry Settle]

We've got a couple of related threads going for related subjects dealing with the 358, 10D etc. . .

I have been hooking up my light meter, either corded or with pocket wizards, to the 10D's pc connection in order to fire the flash and take a reading. So far, this has been working for me. Now PacAce tells me that I shouldn't be able to fire my 420EX in this manner and I am worried that I may, or have already, damaged my 10D.

How do you take light meter readings with your on camera flash setups?

[scottbergerphoto]

The L358 has a mode, that when set, you press the side button, the LCD blinks and waits for the flash exposure. You put the meter where you want it, push the button, then walk over to your camera and fire the flash. I believe it is the mode before full wireless as you cycle through the modes.
Scott

[Harry Settle]

I figured out how to take a reading using that mode Scott, thanks. If I use the pc connection on the meter to the pc connection on my 10D is that wrong? Am I damaging something?

Maybe the real question is "is the pc connection on the camera a two way port?" When the camera triggers, it sends voltage to the hotshoe and the pc connection to fire on or off camera lights. If you input a signal (to the pc connection), does it (or is it supposed to) trigger the flash?

[scottbergerphoto]

I figured out how to take a reading using that mode Scott, thanks. If I use the pc connection on the meter to the pc connection on my 10D is that wrong? Am I damaging something?

Maybe the real question is "is the pc connection on the camera a two way port?" When the camera triggers, it sends voltage to the hotshoe and the pc connection to fire on or off camera lights. If you input a signal (to the pc connection), does it (or is it supposed to) trigger the flash?
I don't know the answer to your question. I know that you can do it via the N3 Terminal.
You need the RS80N3 or similiar cord.
Scott

[Harry Settle]

Looks like I'll at least need the pw to n3 cable and burn a shot or two to take meter readings.

[SkipD]

Harry, the 420EX cannot be used on the 20D in a manual mode, and I doubt if it can be used that way on the 10D. I just tried to over-ride the automated E-TTL exposure control by putting My 20D into M mode with a 420EX on it and doing radically different aperture settings. All the photos in M mode came out exactly the same as the one I did in P mode. For this reason, it makes no sense whatever to meter the flash from the 420EX when it is attached to the camera. You can't do anything about changing the exposure except for adjusting the internal flash exposure compensation.

The 420EX does not have an adjustment for its flash output except for the communication through the camera's hotshoe. You might be able to fake things out by insulating the four pins on the hotshoe and having the flash go off at full power. Then, you might be able to adjust the aperture to set up a particular exposure setting to your liking.

[Harry Settle]

Thanks skip. I've played with it a while this morning and come to the same conclusion. I think that, if I continue to use the 420 very much, I'll make my settings take a meter reading and then use fec to fine tune. Mostly I'll probably stick with the Sigma 500.

[PacAce]

Looks like I'll at least need the pw to n3 cable and burn a shot or two to take meter readings.
I hope you realize that the n3 cable is to trigger the camera so that it takes a picture and not to trigger the flash for a meter reading. Actually, it will trigger the flash, too, so you can take a meter reading but it'll be after the fact since the camera will have already taken the picture.

[SkipD]

My suggestion, Harry, is to use the 420EX for what it is - a great fully automatic flash unit. It can be used in bounce mode, direct, or a combination. Just let the camera do its thing with the flash exposure.

External meter readings will mean nothing, because with E-TTL, the camera automatically controls the exposure electronically as well as via the lens iris (to the best of my knowledge) - even in Manual exposure mode as I found out and mentioned above. You will soon see if you need to make an adjustment to the exposure via the FEC (Flash Exposure Compensation). If you do, it will probably be the same adjustment for almost all shots.

The best use for your flash meter (the same one I have, incidentally) is for an off-camera flash rig - either studio lighting or something like it. Then you can set the camera's aperture (and possibly shutter speed for some special effects) to create whatever effect you are looking for.

[Harry Settle]

I guess that's what I was meaning. I am using a pair of slaves as main lighting and the 420 as fill anyway.

I am also considering a remote trigger for my camera, any suggestions as to which is preferred? Some keep the camera awake and some have option for both.

[SkipD]

I am also considering a remote trigger for my camera, any suggestions as to which is preferred? Some keep the camera awake and some have option for both.Are you wanting a way to take a photo while you are somewhere near but not AT the camera? If so, here's a solution I ran across the other day on a forum, possibly this one.

For the 20D, there is a remote switch that emulates the shutter release button. It has two switches - one that trips when the button is half-way down and the second when the button is fully depressed. The model is RS-80N3. I see that it works on the 10D as well.

Anyhow, the 2-foot cable between the switch and the plug has three conductors in it. A fellow modified his by cutting the cable and installing male and female stereo plug connectors. With this mod, you can use ordinary headphone extension cables (or make your own) to extend the switch quite a distance from the camera.

I am going to do this mod to my switch assembly and use about 100 feet of cable in between the connectors so that I can capture wild animals at our feeders with the camera close to the feeder. The only trick to that is turning off the "Auto Power Off" function so the camera won't turn itself off while waiting for the subject to arrive, and either using the battery/grip for extra battery power or the AC adapter.

[Harry Settle]

I saw that somewhere also. I was thinking more of using the pw with the canon adapter cable to trigger the camera wirelessly. Just trying to decide if I want to spend the money for the cable that has the "half-push" ability, keeps the camera awake, or just plain.

[SkipD]

I saw that somewhere also. I was thinking more of using the pw with the canon adapter cable to trigger the camera wirelessly. Just trying to decide if I want to spend the money for the cable that has the "half-push" ability, keeps the camera awake, or just plain.I've also given some thought to an RF (radio) actuated relay package that would plug into the camera end of the modified RS-80N3. I'm an electronics tech among other things, and just haven't had the time to design the thing. I don't know if the camera will fire properly by just shorting the "full depressed" contact and ignoring the "half-depressed" contact. That could be solved by a simple timing device, though, that would trigger two relays in quick succession with only one trigger signal.

[Harry Settle]

Skip, check out this site for N3 information. If you are an ET, this would be a piece of cake for you.

http://www.camerahacker.com/Canon/N3_Pinout.html