D200 DOF

[ernie.grimes]

I have read the D200 manual concerning depth-of-field preview button and I

just don't get it.

Can someone please tell me how the preview works i.e. when I push the preview

button with the aperture at 1.8 everything looks normal, but if I set the

aperture to F8 or higher it turns darker around the edges.

Thanks, Ernie

[ShunCheung]

That is exactly how depth of field preview works on pretty much all SLR cameras. Since depth of field increases as you close down the aperture diaphragm, during the preview, the camera actually closes it down for you to see the effect, but in the mean time the image in the viewfinder gets darker.

[richard_cochran]

If the pop-up flash is up, the D200 can flash it repeatedly when DoF is used, as sort of a "modelling light" that will somewhat compensate for the dimmer image. This is controllable via the menus, but I believe the feature is on by default.

<p>

But regardless of the brightness/dimness of the image, the important thing is to look at the out of focus areas, and notice that they get less out of focus when the lens is set to a small aperture and the DoF preview button is pushed.

[nolan_ross]

The DOF will get darker as you stop down as you have found. Try to ignore that and look for the out of focus areas. The darker it gets the greater the DOF will be. It takes some practice and many people just cannot use the DOF button. Either it's to hard to visualize the out of focus area's or it's to time consuming. But keep fiddling with the DOF button and see what happens.

[thomas_rutter]

The aperture you select will influence the depth of field of your camera. For example a wide open aperture will lead to narrow depth of field, or in other words, things that are out of focus will look most blurred. A narrow aperture will lead to wide depth of field where things that are out of focus are not nearly as blurry.

 

When you look through the viewfinder you are always seeing it with the aperture wide open, regardless of the aperture setting on your camera. This is because the aperture remains wide open while it's not taking a shot, and closes down to whatever setting while the shot is taken.

 

Depth of field preview will close down the aperture as desired without taking a photo, so you can see the effect in the viewfinder.

 

It will also make it darker in the viewfinder and will make increasingly out of focus things look sharper. Never focus while in depth of field preview mode - focus in normal viewfinder mode.

 

DoF preview is not nearly as useful these days with digital - because you can see the result on the LCD as soon as you take a photo anyway and it's better than pressing the depth of field preview because

- your finger is already on the shutter button

- it will be just as bright

- it is the actual photo taken, ie any slight differences (in alignment, dust, etc) between the viewfinder and the sensor won't matter

- you can zoom right up to get a closer look at the focus and out of focus areas (bokeh)

[juan_parm_nides]

That is DOF. Nothing wrong.

 

Cheers.

[frank uhlig]

Remember, too, that when you look through the lens normally, the lens aperture is wide open at f/1.8. So with the aperture set to 1.8 on a 1.8 lens, the DOF button has no effect. But with the aperture set to f/8, the DOF button will close the lens down, making for a darker view in the finder and a bit more DOF, that is sharpness for objects not right at the focus distance but a bit in front and back of it.

[ernie.grimes]

Thanks everone for your help... I got it

Ernie