Results with ETTL "sick of it"

[william_le]

I spent my Sunday shooting portraits of a guy in midday. I positioned

the guy under a shaded tree with ETTL and had it on +2 and Hi speed

Sync.

 

setting were 2.8 at around 640 to 1000 at ISO 100 using a 50mm 1.4

lens. First of all, The 50mm with 1.6 crop factor makes me have to

stand so far away from the subject just to get half body shots in.

 

Ok my problem is the underexposed flash pictures. 4 out of 5 pics

come out with little or not flash lighting up the person "well not

noticeable enough" I even tried FEL and still didn't light up the

subject as well. I only see the flash working good when I am 1 meter

away from subject.

 

I then used a second flash as a slave setup. This was more effective

with a slide lighting affect but then again the slave didn't fire

half the time and the sensors were facing each other as well.

 

I just wish the 550EX showed how much power it used in the last shot

so you could just set that manual if the flash worked out right.

 

I need a shorter lens that makes up for the 1.6 factor, any ideas on

which one that is as fast and sharp.

 

My techniqe seems correct but ETTL seems to fail on me. Help is

needed guys. Thanks

[walter_strong3]

It sounds to me like you need to have your flash checked for defects.

[everheul]

I do not have a DSLR, but I do have ETTL on my A2E. With multiple flash, I had some problems with underexposure. My guess is that once the meter "percieves" that middle grey has been correctly exposed for, either the shutter is closed or the flash pulse is stopped. I'm not sure how the 550EX works. My flashes are a motley assortment of sunpak, and vivitar manual flashes.

 

I now set my camera to the X setting, use the pc cable, and slaves. I do all my metering with my flash meter and have had no more problems since going fully manual. I'm NOT saying this is the best way, it is just the way I am used to shooting.

 

Since I also use medium and large format, I'm very comfortable with operating fully manual. With diffusers or bounce lighting with multiple flashes, the flash meter is virtually fullproof, but the process is slow.

 

For indoor weddings (regardless of med format or 35mm) I still base exposure on flash to subject distance and shoot manual. With print film, small mistakes are not usually catastrophic.

 

I do use ETTL on snapshots and fill flash.

 

If DSLR's don't allow fully manual operation, then excuse my ignorance. I'm still on the wrong end of the DSLR learning curve.

 

I may go digital if a full frame 6x7 digital back for my mamiya comes down to less than $1000. I'm not holding my breath.

[everheul]

Correction. I have TTL NOT ETTL on my A2e...sorry.

[jbq]

At 50mm 1/1000s the 550EX has a GN of 35ft. At f/2.8 it means that you'll be blasting it at full power for a distance of about 10ft - on alkaline batteries it'll take about 8 seconds to recharge. Trying to reach +2 reduces your working distance to a mere 5 ft.

 

Could it be that you're taking shots too quickly and that the flash doesn't have time to recharge?

 

Could it be that you use the flash so much that it slightly overheated and went into some sort of self-protect mode?

 

Did you try at a shutter speed that didn't require high-speed flash? (1/200s?)

 

Could it be that you had set flash exposure compensation by mistake?

[JosvanEekelen]

In addition to the above answers: have you read N.K. Guy's article about Canon E-TTL flash on www.photonotes.org? It contains lots of information about the peculiarities of the Canon flash system.

[Ken Katz]

Try turning off automatic fill flash reduction (in custom functions), so that the flash will provide full power, and you can use FEC to adjust as desired. High speed flash (above 1/200) will reduce your fill flash range by about 1/3, so it is possible you are running out of flash capacity if you are too far from your subject and expect to see full flash exposure in bright daylight.

 

ETTL produces very subtle fill flash results. If you want an obvious flash look, some override may be necessary.

[PuppyDigs]

<P>The back of your manual contains a table showing the useable flash to subject distance with High Speed Sync. Basically the pulsing of HPS severely reduces flash coverage at 1/1000 sec. Plus, like the above poster mentions, the flash is forced to fire at full charge. Recycling with fresh alkaline batteries takes 7 to 8 seconds. If you fire earlier, you'll get feeble flash or no flash. No amount of FEL or FEC can make up for an under powered flash burst.</P> <P>I have a few suggestions that will help:</P> <BLOCKQUOTE>1. Use normal sync when possible. Thus, your flash has more power and range. For portraits, your 550EX will never have to fire at full strength and recycle times will improve. Honestly, HSS isn't very useful outside of closeup fill.</BLOCKQUOTE><BLOCKQUOTE>2. If you have a fast trigger finger and just can't wait for the flash to fully recharge, get an external battery pack.</BLOCKQUOTE> <BLOCKQUOTE>3. If you're using the 10D, set custom function 14-1, disable automatic fill flash reduction. You sound like you want more "pop" so you can run your 550EX wide open and dial in fill flash reduction when you're feeling understated (this only works in the "Creative Zone").</BLOCKQUOTE> <BLOCKQUOTE>4. Flash exposure is based on the position of the active AF sensor during the moment of exposure. Be sure it is on a medium toned area of your subject. If it falls on a light area--e.g., pale forehead--you'll get about one stop underexposure. Of course, you can always dial in FEC...</BLOCKQUOTE>

[staticlag]

Buy a reflector.

[chuck_dowling]

Turn off the high speed sync, and +2 compensation. Try a couple of shots in P mode, and let the fill flash do its thing, you will like the results.

[whayne_padden]

It doesn't matter whether the high speed sync is on, if you are not trying to sync at more than 1/200 it will operate in normal mode, so you might as well leave it on HP mode. Why you need +2 if the guy is in shade unless he is incredibly strongly backlit I'm not sure, but if he has strong backlighting change position.

 

I haven't had any trouble with 550 EX on my EOS 3.

[william_le]

Thank you all for your responses. I learnt a few hints from a few and he are my conclusions.

 

I do not need to change the BG cause it was bright cause I use the camera in M and the active focus point is on the subject but not always on a medium tone. I'm pretty sure we are can never get the active focus point on a skin tone color. I did try and use FEL but didn't help very much in broad daylight.

 

In future I will take off CF auto fill and wait around 5 secs to charge up. I am also using NMH batteries. Where Can I buy a power pack from to support the 550EX over the net.Thanks guys

[karl_lehmann]

It sounds like you're shooting with a DSLR and your subject isn't going anywhere. In that case why not just put the flash on manual? If the flash isn't powerful enough you'll find out right away. And once you get a good shot you'll know exactly what setting to use!<p>Karl Lehmann <a href="http://www.lostworldarts.com/new_page_3.htm">Lost World

Arts</a>

[william_le]

Karl, I like your idea of manual...but I don't really want to shoot a whole heap of test shots adjusting the flash until I get correct exposure. The model would run out of patience. I do have a flash meter but.

[jonathan_russell]

Buy a Quantum Z or turbo Z battery and the Quantum cable model CZ. This combo works perfectly.

 

In my opinion, your problem is all related to flash recycle...or your flash is broken. If you are (as you say you are) placing your focus point on your subject's skin tone, then you should not be using compensation either. Use the high speed setting only if you need depth of field control that is not possible with the standard e-ttl setting (ie: when the ambient light prevents shutter speeds below 250 given your desired aperture setting).

 

Have fun.

Jonathan Russell