Canon 20D

[alldone404]

Can anyone help please. I have a Canon 400D and a 20D. I use the 20D for night time, high speed fash photography, but in the TV mode while the camera is set to take pictures at 250th of a second, when part pressing the button it drops to less than 20. In AV mode it stays at 250th and with my 400D it stays at 200 in TV and AV mode.

HELP!

 

[CT]

Hiya mate and welcome.

Can you just check that you haven't got those modes the wrong way round in your post.

With the 20D in AV (Aperture Priority) Mode it would be normal for the shutter speed to drop in subdued light, because in AV Mode the flash will always try to balance with the ambient light.

In TV (Shutter Priority) Mode, the shutter speed should stay wherever you set it up to the max flash sync speed of 1/250th.

 

[alldone404]

Hi, many thanks for your reply. Yes, I had got the modes the right way round. In AV mode it stays at 250 and in TV mode it drops according to the light available, just as though there is no flash attached. The equipment is 20D camera, 70-200 2.8 L lens and 580ex Flash.

 

[RobertP]

Think there is a 'safety' feature in the parameters that will override your settings if it is enabled. Could be that as the camera will be trying to take an available light shot in Av or Tv mode... and it can't with that shutter speed. Just need to turn that feature off in custom functions if that is the cause.

 

[alldone404]

Hi RobertP, thank you so very much indeed, just as you said, problem solved. I am indeed very greatful to you. I've been :bang: So easy to do, but only if you know.

Thank you!!

 

[leoedin]

Hi

It seems you must of got these the wrong way round. In all 3 of the Canon camera's (2 DSLR's including a 20D), in Av mode the shutter speed drops due to light, while in Tv mode the shutter speed stays constant at what it was set.