300d and st-e2 - DPChallenge Forums

12/21/2004 10:31:53 AM · #1

Been looking for this answer all morning, can't find it:

With the digital rebel, if the st-e2 is attached and turned on, wouldn't the camera act as though a flash were going to aid in the exposure and auto expose accordingly? Thus making the exposure settings wrong if you only wanted to use the st-e2 as an auto focus assist?

Thanks in advance for your help :)

milo

12/21/2004 10:39:10 AM · #2

12/21/2004 10:47:08 AM · #3

so it can detect if a slave flash is turned on in the room? (or asked differently: how would the camera know when a flash slave is being used?)

12/21/2004 10:55:29 AM · #4

If there is a slave flash in the room the ST-E2 will trigger it. The flash emits a pre-flash milliseconds before emitting the main flash, that pre-flash allows the ETTL mechanism of the camera to meter the scene properly and make the flash output the correct amount of power.

12/21/2004 11:05:29 AM · #5

kewl ... thanks doc

Prof_Fate

12/21/2004 12:01:16 PM · #6

//emedia.leeward.hawaii.edu/frary/st_e2.htm has some info on this

12/21/2004 04:54:47 PM · #7

well ... i just got home from work and tested out my new st-e2, and it's doing exactly what i feared it was going to do. For example:

with the st-e2 turned off, 1/2 push shutter, registers 2.8 at 1 sec in p mode (dark room), take picture ... proper exposure (hand-held and shaky :)

with st-e2 turned on (no flash unti), 1/2 push shutter, registers 2.8 and 1/60 of a second, take picture ... black

with st-e2 on with 420ex on as slave, same exposure value as above ... proper exposure

I'm stumped ... how do i get it to work only as an auto focus assist lamp? I should probly call Canon ... just wanted to follow up.

12/21/2004 05:11:43 PM · #8

just got off the phone with canon ... they claim the st-e2 does not have an auto focus assist beam ONLY feature

:(

ps ... that's not why i bought it, but it would have nice to have

12/21/2004 05:50:12 PM · #9

That`s not quite true. I`ll try it with my rebel and let you know. It might be a feature of 1-series cameras only

Check this review.

12/21/2004 05:57:54 PM · #10

yes, thanks doc ... seems you need to have an eos camera with custom functions that will disable the flash, but enable auto focus assist

(you'd think the canon rep. would know that)

12/22/2004 12:54:50 PM · #11

Actually, I tried it with my Rebel, it works if you use any of the Manual modes like Aperture priority, Shutter priority, full Manual mode. If you use one of the dummy modes it won't work.

12/22/2004 12:56:23 PM · #12

i don't have it in front of me, but that wasn't my experience. i've never used the dummy modes. you weren't getting under-exposures???

Originally posted by doctornick:

Actually, I tried it with my Rebel, it works if you use any of the Manual modes like Aperture priority, Shutter priority, full Manual mode. If you use one of the dummy modes it won't work.

12/22/2004 12:58:51 PM · #13

No underexposure at all, you have to watch the scale at the bottom of the view finder to make sure you are dialing in the correct settings for proper exposure. It works great. I just tried it on all the manual modes.

Originally posted by hopper:

i don't have it in front of me, but that wasn't my experience. i've never used the dummy modes. you weren't getting under-exposures???

Originally posted by doctornick:
Actually, I tried it with my Rebel, it works if you use any of the Manual modes like Aperture priority, Shutter priority, full Manual mode. If you use one of the dummy modes it won't work.