Is that a worn shutter problem ?

<p>I have noticed that when using my 300D with my 580EX in high-speed sync mode

I get a grossly over-exposed band on the left in portrait orientation or on the

top in landscape orientation. <a

hef="http://gallery.ruwenzori.net/main.php/v/misc/FlashShutterProblem/?g2_fromNavId=x838f2e68">Here

are three samples frames showing this shutter or flash problem</a>. The body is

a 300D with about 50000 frames shot during its lifetime. Considering how the two

curtains operate in high speed sync I suspect the problem may be caused by bad

shutter timing caused by a worn out shutter. Has anyone else seen that before ?

Any idea what it might be ?</p><div></div>

<p>Sorry for the bad link... Here is the right link to the <a

href="http://gallery.ruwenzori.net/main.php/v/misc/FlashShutterProblem/?g2_fromNavId=x838f2e68"> three samples frames showing this shutter or flash problem</a>.</p>

I must add that this phenomenon does not occur on each frame. I occurs randomly and only about half the time. I don't think I have seen it it normal flash sync mode - but I am not sure.

Perhaps the flash is not actually firing in high-speed sync mode despite your settings. A normal flash when the camera is set higher than the normal sync speed would create this effect. If I'm right, the height (or width, on a vertical picture) of the band will vary inversely with the shutter speed.

<p>

> Perhaps the flash is not actually firing in high-speed sync</br>

> mode despite your settings. A normal flash when the camera</br>

> is set higher than the normal sync speed would create this effect.</br></p>

<p>

Could I mistakenly have used the flash in normal sync mode above the highest possible sync speed (1/125 on the 300D) ? I have to check if that mistake is possible or if the body refuses to take the picture.

</p>

I checked if with normal flash the body lets the user shoot a frame above max flash sync : it does not - speed cannot be set above 1/200. So the two remaining solutions would be a worn shutter or the flash pretending to be in high speed mode and actually being in normal mode. The most annoying part of the problem is that I have a hard time reproducing it. Yersterday evening, I between this problem a a spate of "error 99" I missed a good third of my shots. Today I cannot reproduce either problem...

If it was the shutter you would see it on shots where there is no flash used.

 

What mode are you using?

 

If your not using AV mode try taking several shots in that mode to see if it accures.

Also, if you have Rear/Second Curtain Sync enabled try turning that off also.

All the frame I have shown here were captured in Av at f/2.8

 

There is no second curtain flash option on the 300D.

 

The artefact only showing in frames captured with flash does not exclude a shutter problem : maybe in frames captured with no flash the problem only shows as slight exposure error.

 

I should test that flash on another body. The problem is that I can't reliably reproduce the problem...

I have seen shots exactly like that before on film when I was in school.

 

Usually this problem is caused when a shutter speed faster than the sync is used.

 

If you were to meter and you get a reading of say f/11 1/125. Then you change to manual mode and set the exposure to f/4 1/1000 you would see results similar to yours. So it lloks to me as something is set wrong, or there is a problem with the Camer to Flash communication.

 

 

Have you updated your firmware?

The firmware is the original 300D release, but the firmware updates have only adressed problems with remote capture and PTP transfers so I don't think the update would fix my problem.

 

I'll definitely have to check the flash with another body and the body with another flash to check for a communication problem between flash and body or the malfunction on one of them.

 

But as you suggest the most likely cause is user error... Which may explain why I have a hard time reproducing the problem. I'll be extra careful next time...

 

It is quite frustrating to be unable to nail the exact cause... If I ever find out I'll post it here.

 

Anyway thanks to J Benton for the suggestions !

My main reason for no thinking its the shutter is if you look at the Top Left and Top right corners the exposure looks egual, it is only the forground and subject that look over exposed on the left side.

 

Look at how the over exposure seems to perfectly align with the mans back arch. if it was the shutter it would most likely over expose everything on that side of the shot.

 

Please do report the cause if you ever find it.

 

Good Luck

 

P.S. Its always better for it to be user error rather than equipment....You can fix user errors for free.