[olaxip]

Hi i never really use this A-AEP mode before so thought id give it a go. My manual says the following:

1 set the mode dial to <a-aep>
2 focus the subject
Move the AF point over the subject and press the shutter button half way (followed by a sign that looks like a clock and a number 4)?
all the subjects covered by the AF points flashing in red will be in focus.
Hold down the shutter button halfway and press the depth of field preview button to see the depth of field.

Now i follow the above but absolutly nothing happens apart from the scene im seeing in the viewfinder goes about 50% darker and there is a slight noise like something has just focused. But no numbers change nothing so what am i meant to be seeing/doing?

please advise

[Dabhand16]

The depth of field preview will show you in the viewfinder what will be in focus and what will not. You have to look at the image, not the digital info.

The noise you can hear is the lens being stopped down to the set aperture, and this is why the viewfinder looks darker - the amount of light entering the camera has been reduced from the maximum aperture that is used to view things normally.

If, by chance, you were using the maximum aperture to take the picture, there would be no difference in the lightness of the image you can see in the viewfinder.

[morlandroger]

Am I missing something? My 30D has A-DEP but not A-AEP. Prefer to use AV and set the depth of field myself and set focus with Hyperfocal distance (or an estimate there-abouts). Tutorial here Hyperfocal Distance and why you should care.. Brought back film day's memories and lenses that had more markings than todays'.
Roger

[olaxip]

I shall have a good read of that HFD link thanks

[quote=Dabhand16;202776]The depth of field preview will show you in the viewfinder what will be in focus and what will not. You have to look at the image, not the digital info.QUOTE]

How or what am i meant to be looking for in the viewfinder? it just goes darker and thats it, i dont see anything that shows me what will or wont be in focus. Also i dont recall being able to change the appature in this mode should i be able to? One last thing what is the sign that looks like a clock and a number 4 in the manual mean

[Dabhand16]

Originally Posted by olaxip

How or what am i meant to be looking for in the viewfinder? it just goes darker and thats it, i dont see anything that shows me what will or wont be in focus. Also i dont recall being able to change the appature in this mode should i be able to? One last thing what is the sign that looks like a clock and a number 4 in the manual mean

You have to use your eyes to see what is and what is not in focus!!

You look at the image you can see in the viewfinder and if the elements you want in focus are in focus, you are OK. If they are not, or if the depth of field is too great, you make the necessary aperture ajustment then re-check using the depth of field preview button again.

I don't use a Canon, so have no idea of what the display means.

[silkstone]

I share Roger's confusion - the Canon 30D does not have an A-AEP mode.

It has an A-DEP mode which gives a guide to DEPth of field by illuminating the AF points that lie over the parts of the frame that will be in focus at the aperture and focal length you have chosen, when you half press the shutter button to auto-focus.

The clock symbol with the number 4 in the manual means that it holds this focus for 4 seconds after you release the button.

While keeping the shutter half pressed, you can also press the depth-of-field preview button which closes the iris to the aperture you have selected. This will make the image darker unless you've selected maximum aperture. As Graham says, you then have to look carefully to see what appears to be in focus.

The DoF preview is all but useless except in good light, especially with a smallish viewfinder, so I wouldn't worry too much about that. The AF point illumination may give you a guide to the depth of field, except that it does depend on the AF points being over the parts of the image you're interested in.

All in all, if the A-DEP mode wasn't there, I wouldn't miss it.

[fionaB]

well i have to say i tried mine, and decided using my eye and judgement probably had a more reliable effect! lolol or maybe i was doing something wrong. so like silky says... i wouldnt bother about it.

Fi

[olaxip]

Hi sorry A-DEP mode is what i meant. Thanks guys for pointing out what its supposed to do. After testing this further im with silkstone on this its one function i wont be using again and wouldnt miss it if it wasnt there

thanks for the guidance