question about off-camera flash

[dr_who]

Hi, I'm relatively new to using flash. I have a sigma dg super, and would like to use it as a off camera flash. I've used the search tool, but there are way too many terms I don't understand and it just got me more confused.

1) what product do I need to buy to mount it on a tripod?
2) if I use it as an optical slave, triggered by built-in flash, I hear there is preflash problem? can I void preflash problem by using FE button "*" in advance, so the camera doesn't preflash again when I press shutter? any setting i can disable preflash altogether?
3) what is a pc/hot shoe adapter/cord? is it different from a regular off camera cord? I know doing the optical slave way I need to manually set flash power. If I want to use a cord which one do I need?
4) considering cost, would it be worth it to buy another sigma dg super or other cheaper unit so I can use wireless trigger? if I go that route both flash will be controlled by ETTL and the flash ratio I set, ie, I don't need to manually set flash power, right?
5) I see some radio flash transmitter for around $20 on ebay. if I buy one of those will I be able to get ETTL?

[Curtis N]

1) what product do I need to buy to mount it on a tripod?Since your camera has no PC socket, you need a) a Hotshoe to PC adapter like this (http://www.bhphotovideo.com/bnh/controller/home?O=Search&A=details&Q=&sku=89979&is=REG&addedTroughType=search)on your camera's hotshoe, b) a PC cord like this (http://www.bhphotovideo.com/bnh/controller/home?O=Search&A=details&Q=&sku=52945&is=REG&addedTroughType=search), and c) a PC to hotshoe adapter like this (http://www.bhphotovideo.com/bnh/controller/home?O=Search&A=details&Q=&sku=95414&is=REG&addedTroughType=search)to mount the flash on. This adapter has a 1/4-20 threaded hole in the bottom for mounting on a tripod.2) if I use it as an optical slave, triggered by built-in flash, I hear there is preflash problem?Yes.can I void preflash problem by using FE button "*" in advance, so the camera doesn't preflash again when I press shutter?Yes. It's a royal pain, though.any setting i can disable preflash altogether?Not with the built-in flash.3) what is a pc/hot shoe adapter/cord? is it different from a regular off camera cord? I know doing the optical slave way I need to manually set flash power. If I want to use a cord which one do I need?"PC" is a type of connector. A PC cord is a cord with this kind of connector on the ends. The cord has only two conductors and only allows the camera to close a circuit to trigger the flash. Manual control only with this method, no E-TTL.

The Canon Off Camera Shoe Cord 2 is a completely different animal. It has six connectors to completely replicate the camera's hotshoe and allow communication with the flash for E-TTL control. The limitation of this cord is that it's only a few feet long.4) considering cost, would it be worth it to buy another sigma dg super or other cheaper unit so I can use wireless trigger? if I go that route both flash will be controlled by ETTL and the flash ratio I set, ie, I don't need to manually set flash power, right?I have two Sigma Supers and yes, you can use a master & slave with E-TTL control. My experience is, it's not a very reliable system and I have better luck with one unit in manual mode and one in optical slave mode. If you just want to experiment with off-camera flash, the Sunpak 383 is a much more economical option (see my review in the stickies).5) I see some radio flash transmitter for around $20 on ebay. if I buy one of those will I be able to get ETTL?No, only manual control. Even with the much more expensive PocketWizard systems, you need to set the power manually.

[dr_who]

Thank you Curtis for your very detailed answer. So it looks like the cheapest way to do off-camera flash with ETTL is to buy a camera off camera cord? Does the cord end has a hole so I can mount it on a tripod?

Without a light meter, I guess it must be very difficult to come up with the correct manual setting for the off-camera flash? Do you just take a shot and look at LCD and adjust the power and re-try?

[EOS_JD]

Deleted my txt as Curtis got it all :-)

[Curtis N]

So it looks like the cheapest way to do off-camera flash with ETTL is to buy a camera off camera cord? Does the cord end has a hole so I can mount it on a tripod?The Canon Off Camera Shoe Cord 2 that I mentioned is for use with flash brackets and really isn't long enough for any other purpose. There is a thread in the DIY stickies describing a way to extend it if you go that route.Without a light meter, I guess it must be very difficult to come up with the correct manual setting for the off-camera flash? Do you just take a shot and look at LCD and adjust the power and re-try?If you're using direct flash, Sigma makes it a little easier. You can dial in your aperture and ISO setting, and the distance scale on the flash will guide you. If you're bouncing or using an umbrella or some other diffuser, it's more of a trial-and-error process. With experience, you learn to guess pretty close.

[dr_who]

Curtis, thanks again for your answers. Looks like there's really not much to gain with a off camera PC cord/adapter except I need to press "*" in advance to avoid preflash. I'll give it a try with what I've got and see if I need to buy additional stuff.

[Curtis N]

dr_who,
This thread (http://photography-on-the.net/forum/showthread.php?t=246797) might give you a few ideas to think about.

[dr_who]

Thanks a million. I think I will end up buying this flash as well. I always find the wire somewhat troublesome, and there are radio transmitters on ebay for about $20. I guess since this one has sync socket, it'll work perfect for the set up! I'm so excited.

dr_who,
This thread (http://photography-on-the.net/forum/showthread.php?t=246797) might give you a few ideas to think about.