As I read on http://www.kjsl.com/~dave/wireless.html, E-TTL can be used in a master-slave 550Ex/420EX combination. Is this only true for Eos 3 and 1v?. If I am correct, only with these two cameras the ratio control is possible (?)

What about Elan IIE (50E) and 550EX. Do I lose something of the fancy EX550? I think I would prefer the FP (focal plane I guess) function of using short exposure times (shorter than 1/250 sec), does it work with Elan II.

If it does, does the master/slave combo work in FP mode?

In the page http://www.photozone.de/canonflash.htm#mid is described METZ 54MZ3, which seems to have all the functionality that 550EX has!!! (I think it cannot be used as E-TTL slave, I don't know ...)

What about TTL master/slave combinations with 550EX(420EX) as master and some other (cheap) slave flash unit(s)?

-- Matija Ponikvar (matijap@robo.fe.uni-lj.si), November 28, 2000

Answers

With FP I actually ment High-speed synchronization, for fill-in flash at daylight.

-- Matija Ponikvar (matijap@robo.fe.uni-lj.si), November 28, 2000.

All type "A" EOS bodies (1V, 3, 50E, 500N, 300, and variants) can use wireless E-TTL flash (including FP flash). All type "A" EOS bodies can use the 550EX (or the ST-E2 and MR-14EX) as a master and use one or more 550EX or 420EX as a slave. However, only the EOS 1V and EOS 3 are capable of ratio control and modelling light.

The only speedlites (Canon or otherwise) that I know of which are capable of being a wireless E-TTL slave are the 550EX and 420EX.

-- Dave (dherzstein@juno.com), November 28, 2000.

I have another question regarding master/slave operation. Can the EOS50 (Elan II) built-in flash be used as TTL (or E-TTL) master with 550EX or 420EX)? Thanks in advance!

Matija

-- Matija Ponikvar (matijap@robo.fe.uni-lj.si), November 29, 2000.

Can the EOS50 (Elan II) built-in flash be used as TTL (or E-TTL) master with 550EX or 420EX)?
TTL only; no E-TTL or master.

-- Dave Herzstein (dherzstein@juno.com), November 29, 2000.

I believe the Elan 7/7E can provide ratio control.

-- C.A. Thorne (cthorne@us.ibm.com), December 06, 2000.