Pre-flash on IXUS cameras and S-TTL

[anferney]

Hi All,

I've been crawling around the boards doing research for a while now, but this is my first post (of many more to come hopefully ). Anyway, thanks for all the useful info so far...

I have a question I can't find a good answer for... It's regarding S-TTL flashes and compact cameras. Specifically, I have a Canon IXUS 100is (SD780) compact camera and I'm planning to get the Inon S-2000 strobe.

As I understand it, for S-TTL to function correctly, the camera must send a pre-flash. My concern is this - I have noticed that my IXUS 100is does not ALWAYS pre-flash. I can have the camera on exactly the same settings and depending on the lighting of the scene it will pre-flash or not. (Even when I have the flash set to always ON.)

I know that I can set everything to manual as a workaround, but I really like the idea of S-TTL.

How will the strobe handle the intermittent pre-flash? Am I missing something obvious here? Has somebody had experience with the Ixus 100is (SD780) and S-TTL?

Many thanks!

Anferney

 

[Nemrod]

I don't have you camera but I have several Canons. Some cameras emit a red-eye reduction flash, perhaps you are confusing that with the pre-flash. If the camera utilizes a pre-flash it will fire that pre-flash every shot unless it is user selectable as on some Canons. You will need to configure your S20000 for the pre-flash configuration (for sTTL mode), set your camera for no red-eye reduction and for the sTTL mode set your camera to program/auto and set flash to ON (Forced) and set the S2000 to the sTTL setting.

N

 

[anferney]

Thanks Nemrod. It's certainly not impossible that i'm getting confused...

I saw a thread before that suggested you could see the preflash. If I turn off red-eye and set the camera to program/auto i can sometimes see two distinguishable flashes, but most of the time only one flash.

Maybe the two flashes are so close together they appear to the human eye as just one flash?

Anyway, I have ordered the S2000 today, but it has to be imported since our local disti in South Africa doesn't keep any stock. As soon as I have it i'll test it and let you know...


Thanks,
Anferney

 

[alien]

Nemrod
For the preflash use with the Canon G10 do I use the magnetic thingy or not?
Also do I need to use the silver camera clips (mirrors) that came with the wireless kit?
It seems to be firing okay without using these (on land anyway). Sorry for these question but the Japlish instructions and poor photos are hard to follow

 

[Nemrod]

Nemrod
For the preflash use with the Canon G10 do I use the magnetic thingy or not?
Also do I need to use the silver camera clips (mirrors) that came with the wireless kit?
It seems to be firing okay without using these (on land anyway). Sorry for these question but the Japlish instructions and poor photos are hard to follow

I don't have the G10 nor am I sure which "wireless" kit you might have, however, there are some universal considerations especially with Canon cameras. The G10 behaves pretty much the same as my 570 or any other Canon P&S. When your G10 is selected to either manual exposure or you select the G10 flash to manual (in Av or Tv auto modes) then the preflash is canceled. If you select auto or program on the G10 then the pre-flash is re-activated until you return to Av or Tv modes (assuming G10/570/590/640 etc flash is selected to manual). Full auto mode or program mode overrides the flash manual selection back to the preflash mode.

So, let's see, for your G10 the magnet should be installed, your G10 internal flash should be selected to "manual" or lowest power. The G10 set to Av, Tv or manual set the D2000 to either external auto mode and match f stop or set the G10 to full manual and select the D2000 to manual and set strobe power to match f stop and desired exposure. With your G10 in program set the D2000 to sTTL mode, usethe EV control to lighten or darken exposure. Setting to sTTL mode cancels the magnetic switch position until the D2000 is selected to either manual or external auto.

If you are using the fiber optic cable then you need to use the mirrors I would think. The D2000 works best, especially in the sTTL mode with the camera's strobe covered with the Inon Clear Photo Film or a piece of developed, unexposed slide film.

I think I am telling you right, let me think a moment.

N

 

[anferney]

Hi,

To answer my own question - I now have two S2000 strobes connected to my IXUS 100is via optical cable and everything works perfectly in S-TTL mode.

Here is a sample picture:

I can't upload a sample picture to my gallery because it keeps timing out for no reason and i'm not allowed to link to my photo gallery - so you'll just have to take my word for it.............

Anferney

 

[Nemrod]

Hi,

To answer my own question - I now have two S2000 strobes connected to my IXUS 100is via optical cable and everything works perfectly in S-TTL mode.

Here is a sample picture:

I can't upload a sample picture to my gallery because it keeps timing out for no reason and i'm not allowed to link to my photo gallery - so you'll just have to take my word for it.............

Anferney

Image hosting, free photo sharing & video sharing at Photobucket


N

 

[anferney]

this post is simply to take me up to 5 posts...

 

[anferney]

this post is simply to take me up to 5 posts.......

 

[anferney]

Here is a sample pic with the IXUS 100is, two S2000 strobes running in S-TTL mode.