Julian Loke <[EMAIL PROTECTED]> wrote/replied to: >I am sure that you have lots of new EOS toys to play with, but just in case >you are interested, there is an interesting thread about flash ETTL metering >at photo.net > http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=004brM > >Cheers >Julian Loke
Julian, very interesting reading, but more confusing that anything. I will have to do more tests, but I'm pretty sure my EOS 55 uses partial metering when in ETTL mode. Does not the CF8=1 say it will use partial metering on the active sensor instead of the central sensor? I thought I confirmed that it does, at least when partial metering is set in camera. But I'm going to test it again, I really want to know this one. Ok, another test complete. My EOS 55 very definitely uses partial metering on the active focus point with and without ETTL flash. That is with partial metering on camera set, CF8=1, single shot mode. The exposure reading does not vary from without flash to with flash. I'm using a brand new 550EX. I setup a box with a black area under the left side focus point, and white under the other two points. I can definitely see a 2 1/2 stop difference from the sensor on the black to the other two on white, with and without ETTL flash. By the way I found it very tricky to use FEL while holding down the shutter half way to get ECF on the left sensor, then pushing the FEL button. It would be much easier to let it use the central sensor on the subject, then recompose, or of course setting the camera manually first, to use the focus point desired. This is where the buttons on the back of the EOS 7 would shine :-) I was wondering though, if focus was assigned to the FEL button by CF4=1, if one could set FEL and focus on the ECF sensor. So I did another test, using CF4=1. Interestingly, I got no FEL at all, and the shutter button pressed half way didn't seem to do anything. I certainly did get focus on the sensor desired. I wonder if a photo was taken if ETTL would expose correctly for that focus point in this case. I suggest CF4 should not be set to 1 for FEL. I understand though that the EOS 3 and 1V can do separate flash and ambient exposures, perhaps this way. I hope this all makes sense. I don't know if the EOS 55 is any different than the Elan IIe, but maybe it is, since my test results are different. I will of course now have to do an actual sample on film and see how the exposure is. I will try regular and backlit subjects. Jim (Still finding my rear control dial a nuisance - just noticed it still set for 2 stops over - good thing my last few shots were on negative film!) * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
