Originally posted by fevbusch On my K100D. When using my Sigma 50mm 2.8 lens I stop down after every shot by pressing the AE-L lock, after getting my focus. It also stops the camera from Hunting and I think gives me better depth of field.
While glancing thru the k100d manual I noticed that they say after locking the AE-L you have to hit it again to unlock it after the shot.
Should I be doing that. After all I'm taking many shots at different focuses and I don't think it should stay locked when I'm doing that. What do you advise. Fred
Hi Fred,
If I read your post correctly there are some misunderstandings here:
Quote: I stop down after every shot by pressing the AE-L lock, after getting my focus.
I interprete this as you you aim, focus and get focus and then press the AE-L button. If that is correct you have now the target at the right place and focused. By pressing the AE-L button you also have told the camera to lock the exposure at the values showed in the viewfinder bottom, where a * also is shown now. This doesn't mean you have stopped your lens down. That will happen automatically when you press the trigger, the f-value read in the viewfinder is now locked and the camera stops down and lifts the mirror and opens the shutter the time shown in the viewfinder.
Quote: It also stops the camera from Hunting and I think gives me better depth of field.
Hmm... The focus is locked when it is locked. Fixating the exposure values does nothing here. If your camera is set to continues focusing it tries to focus all the time, if it is set to one shot mode it stays where it is as long as you keep the trigger hal pressed.
The depth of field is determined by the aperture opening (presuming you don't move and refocus and zoom (hard with the Sigma) and all that). You check the DOF) loosely at least) by moving the ON-OFF switch to the aperture symbol. You can set the camera to Aperture priority mode and change the aperture with the thumb wheel checking the DOF. When satisfied you know what aperture you want to use. If you have locked the exposure value with the AE-L button you can use the thumb wheel and alter the aperture opening til' you get the value you want (the camera will change the shutter time accordingly not to alter the exposure value (at least with the DS)). Again, the aperture opening determines the DOF and exactly when the lens is stopped down doesn't matter: before taking the picture or not will make no difference as the lens will get stopped down anyway the moment you press the trigger all the way down.
Quote: While glancing thru the k100d manual I noticed that they say after locking the AE-L you have to hit it again to unlock it after the shot.
I think they mean you have to press it again to release the camera from the previous order you gave it. When you press the AE-L button the exposure value will be locked, and stay locked as per Steve's reply.
In practise this means you have the camera set to the same exposure value (shutter time and aperture) until you press the AE-L button once again (or the metering time runs out).
This is good if you want to take several pictures of one subject and the light hasn't changed between the shots. If the light changes, or you walk away and decides to take a picture of something else, you can release the meter and let it do it's job again. Your choice.
Quote: Should I be doing that. After all I'm taking many shots at different focuses and I don't think it should stay locked when I'm doing that. What do you advise.
If take several pictures of something and want to change the focus only a bit between these pictures you should let the exposure value stay locked. Concentrate upon focusing and rest assured that the exposure will be correct as you allready have measured the light when taking the first picture. Why shouldn't the exposure value be locked?
From the last reply:
Quote: So, Steve, how do I stop down the lens. Somebody once said to move the on off switch of the camera to the "aperture symbol. But when I did that the camera instantly took the picture. Is it supposed to do that?
The camera stops the lens down, when taking the picture. If you mean to check the DOF you should turn that ON-OFF switch to the aperture symbol as allready discussed. The camera is not supposed to take a picture because you do that. I guess you pressed the trigger by accident if that happened.
Are you talking macros here? If so I think you should turn the camera to manual focusing. That way you don't have to bother with the trigger and hunting and all that stuff. You can focus, lock the exposure, check the DOF, choose aperture and refocuse til' you are satisfied. I sometimes justtouch the trigger to reactivate the meter so the time doesn't run away from me. Or go to manual exposure alltogehter, determine the exposure and then fiddle with focusing. Then you have to change the shutter time accordingly if you change the aperture value, naturalmente)
A long post... please report back if I misunderstood anything here.