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clicky
20th of February 2005 (Sun), 02:41
First things first. I've got the 1D II and I'm far away from home, the user manual is also at home.... :o

How do I make sure that E-TTL II is running properly? I'm not to happy with the expo-performance with my current settings - I use a Speedlite EX 550. Any help apprechiated, this is kinda urgent..

tim
20th of February 2005 (Sun), 02:50
I don't think you can't turn ETTL II off, and ETTL II never degrades to ETTL 1. CF 14 changes something, but I don't understand entirely what. Read the sticky thread in this forum for lots and lots of info.

What's wrong with your photos?

scottbergerphoto
20th of February 2005 (Sun), 05:15
In short, as I am short(yeah I know I'm a riot), you have two options for ETTLII, Evaluative (14-0) and Averaging (14-1). Evaluative evaluates the reflected light from the preflash and ignores the data from sensor zones giving very high or low values. Averageing takes the data from all the sensor zones and averages them. Averageing is mostly used for indoor flash. I have found ETTLII to be very consistent if you use the camera in Manual Mode and the flash in ETTLII, regardless of whether 14 is 0 or 1. I take a test shot and adjust FEC based on the histogram.
Just a reminder, ETTLII is totally independent of AF points.
There is more in the EOS Flash Sticky.
Scott

Tom W
20th of February 2005 (Sun), 05:52
First things first. I've got the 1D II and I'm far away from home, the user manual is also at home.... :o

How do I make sure that E-TTL II is running properly? I'm not to happy with the expo-performance with my current settings - I use a Speedlite EX 550. Any help apprechiated, this is kinda urgent..

In addition to what Scott says (and Scott knows flash very well), if your shots are consistently over or under-exposed (all or most the same way), you might be well off to dial in some flash exposure compensation and leave it set until you can get some additional reading done.

Also, if flash is your primary light source, shoot either in P mode or M mode. In P, the camera will set shutter and aperture for you, but will not go slower than 1/60 second. In M mode, you can set the shutter and aperture as you wish and the flash will expose properly for you.

If you use Av or Tv, the flash acts as fill flash - the camera will adjust itself for accurate exposure for the ambient light first, then the flash will fire as fill light only. This can cause very slow shutter speed in Av, and wide-open aperture in Tv. You may not want either in your situation.

But do read the sticky thread on Canon flash when you get a chance. Its full of information and resource links.

clicky
20th of February 2005 (Sun), 06:23
Thanks for your help, I'll look into the article mentioned above. But as far as I know there is no pre-flash (there's one "mainburst" only and therefore no pre-flash measuring...?) and my 550EX has a tendency to over-expose nearby objects within approx 6- 10 ft. This occurs at any ISO from 50 - 800, and shutter 1/60 - 1/250, and even at the more or less "safemode" ex. 1/60 f/4.0 ISO 200... (there is no spot-metering activated - I've checked this.)

An snapshot example using 17-40 f/4.0L @ 28-35 mm: I aim/focus - focus on spot/focus confirmed. I shoot and the object measured is "blown away" by the 550EX, even in evaluative measuring. The next picture (with same procedure) is somewhat better but far from acceptable (and yes - the built in 17mm spreader on 550EX was not in use...)

Tom W
20th of February 2005 (Sun), 06:40
The preflash is too quick to see - it happens between the time you depress the shutter and the image is actually taken. You won't notice it.

Does your 550EX say "ETTL" on the rear panel, or "M" or "Multi"? It should be E-TTL. Cycle the "mode" button until it says "ETTL".

Check the setting on both the flash or camera for +/- compensation. On the flash, hit "sel" and see if the compensation is +something, -something, or 0. Use the + and - buttons to adjust to 0. Do the same on the camera by pressing the metering/ +/- button and turning the rear dial until the FEC is centered at 0. (make sure the rear dial is turned on).

Then, press the "sel" button twice to make sure that bracketing is set to 0 (use the + and - buttons to set it there if it is not).

Check zoom matches the lens focal length (if on the camera and turned on). If the flash is not on the camera, the zoom should read " - -". If not, keep depressing the "zoom" button until it reads that way.

Next, check across the top of the flash display - it should read "E-TTL", then "zoom - - mm", with no other symbols. If there are any other symbols, depress the "+" and "-" buttons simultaneously 1-3 times until all symbols are gone.

What I'm doing here is trying to get you to the default settings on the flash. From there, you can move exposure compensation up or down as needed to get what you want.

clicky
20th of February 2005 (Sun), 07:53
Done that! I've been through your intructions and now it seems as though the flash-exposure has been tampered with, probably me and my ten thumbs... :)

How fast is the pre-flash? I guess it's fast+++ but shouldn't I be able to see/register it when not looking in the viewfinder?

Anyway - I've taken a few test-shots now and it seems as though it's OK and back to normal. You've saved my day - thanks!

Tom W
20th of February 2005 (Sun), 08:03
Done that! I've been through your intructions and now it seems as though the flash-exposure has been tampered with, probably me and my ten thumbs... :)

How fast is the pre-flash? I guess it's fast+++ but shouldn't I be able to see/register it when not looking in the viewfinder?

Anyway - I've taken a few test-shots now and it seems as though it's OK and back to normal. You've saved my day - thanks!



You're welcome - the flash isn't real intuitive. Its just something that you have to mess with for a while.

As for the pre-flash, I've never been able to see it. Others may have, but it is very fast. Its also weaker than the main flash which may make it harder to see.

robertwgross
20th of February 2005 (Sun), 09:05
I think that the only good way to see the pre-flash is to set the camera and flash for a slow shutter and second-curtain sync. But then, once you are convinced that it is actually firing, put everything back to normal.

---Bob Gross---

PacAce
20th of February 2005 (Sun), 09:32
You can always see the pre-flash if you look through the viewfinder unless, of course, if you are out in the sun and using the flash as fill and even then, there's a good chance you'll still see it.

Tom W
20th of February 2005 (Sun), 09:41
You can always see the pre-flash if you look through the viewfinder unless, of course, if you are out in the sun and using the flash as fill and even then, there's a good chance you'll still see it.

Well, that makes some sense, actually. You aren't going to see the main flash as the mirror will be up, so I guess if you see any flash at all in the viewfinder, it will have to be the preflash.

scottbergerphoto
20th of February 2005 (Sun), 10:02
You can trigger the preflash by hitting FEL.
Scott

Tom W
20th of February 2005 (Sun), 10:21
You can trigger the preflash by hitting FEL.
Scott

I thought that was the "modeling" light. It did come in hand a few weeks ago during the ice storm when the power went out. It was my flashlight until I got to the car to get the real flashlight. :)

EDIT: Sorry - I was confusing the DOF preview button with the FEL button. Too many acronyms. :)

scottbergerphoto
20th of February 2005 (Sun), 12:28
When you hit the FEL button, the camera fires the pre flash and determines how much flash output is required for the composition at the time. With ETTL this allowed you to focus on the subject, hit FEL and recompose before taking the picture. With ETTLII, which isn't based on active AF points, this is no longer necessary.
Scott

PacAce
20th of February 2005 (Sun), 13:03
When you hit the FEL button, the camera fires the pre flash and determines how much flash output is required for the composition at the time. With ETTL this allowed you to focus on the subject, hit FEL and recompose before taking the picture. With ETTLII, which isn't based on active AF points, this is no longer necessary.
Scott
Just for clarifaction, when FEL is used to preset the flash exposure, the camera uses the same central area of the viewfinder that is used for partial metering, whether it's in ETTL or ETTL-II. So if you want to meter off a particular part of the subject, you would have that part covered by the circle in the middle of the viewfinder and then fire the preflash with the FEL button.