DOF Preview button When to use and for what purpose: I shoot a Nikon D7100. Heard a guest speaker at our club the other night recommend the use of that button. Is there more than just...

Tallyann

I shoot a Nikon D7100. Heard a guest speaker at our club the other night recommend the use of that button. Is there more than just pushing the button? My viewer dims, but I don't understand if there is information there to be gained. Anyone?

Linda From Maine Loc: Yakima, Washington

It enables you to view the scene with the aperture you selected so you can see how much is actually in focus. You may wish to have a shallow depth of field (out of focus background) or you may wish to have as much as possible in sharp focus, such as with many long-view landscape shots. This button allows you to see what your aperture choice achieves prior to taking the shot.

DanielB Loc: San Diego, Ca

That's exactly why I don't use it. It shuts down the aperture blades so it dims what you see. It's easier to take a shot and look at the DOF on your LCD for the results than to use the DOF Preview button. Then just stop up or down to change.

Tallyann wrote:

I shoot a Nikon D7100. Heard a guest speaker at our club the other night recommend the use of that button. Is there more than just pushing the button? My viewer dims, but I don't understand if there is information there to be gained. Anyone?

rmalarz Loc: Tempe, Arizona

Excellent answer, Linda.

I use the DOF preview button on my cameras extensively. That's the best way to know before you expose what will and won't be in focus.
--Bob

Linda From Maine wrote:

It enables you to view the scene with the aperture you selected so you can see how much is actually in focus. You may wish to have a shallow depth of field (out of focus background) or you may wish to have as much as possible in sharp focus, such as with many long-view landscape shots. This button is a tool to help see what your aperture choice achieves prior to taking the shot.

pesfls Loc: Oregon, USA

rmalarz wrote:

Excellent answer, Linda.

I use the DOF preview button on my cameras extensively. That's the best way to know before you expose what will and won't be in focus.
--Bob

Me too. That’s because we’re both old enough to have used cameras long before anybody had heard of an lcd screen. Old habit that remains valid today. Yes the viewfinder darkens so one must use a critical eye to evaluate the dof but it works fine once one is used to it.

ORpilot Loc: Prineville, Or

I shoot Sony equipment so all I have to do is hit the Manual focus button and everything that is in focus is highlighted in yellow, white or red. Nothing is dimmed in Sony Cameras. I use it all the time to check composition. Looking back on my film cameras, I used the scales on the lens to check DOF. With my M645, 4x5, and 8x10, I definitely used DOF preview all the time. It is just one more tool to improve your photos. Happy Shooting

rmalarz Loc: Tempe, Arizona

I have a sort of huge "LCD" screen on the back of my 4x5. One just has to learn to view the world upside down. But, that really helps with composition.
--Bob

pesfls wrote:

Me too. That’s because we’re both old enough to have used cameras long before anybody had heard of an lcd screen. Old habit that remains valid today. Yes the viewfinder darkens so one must use a critical eye to evaluate the dof but it works fine once one is used to it.

bkyser Loc: Fly over country in Indiana

I have to admit, I don't use it any more. Mainly because my eyes are just too old and tired to see enough in the lower light. I'm fairly certain you can reassign that button to something else if you want. Maybe someone else knows more than I do, but I thought it can be made into a custom function.

SteveR Loc: Michigan

DanielB wrote:

That's exactly why I don't use it. It shuts down the aperture blades so it dims what you see. It's easier to take a shot and look at the DOF on your LCD for the results than to use the DOF Preview button. Then just stop up or down to change.

I'm not sure why, but when I shot with a film camera using a Canon 50mm (or was it 55?) f1.8 lens I did not have this "darkening" problem that you speak about. However, when using lenses on my D7100 that were not as fast I experienced the same problem that you did. The d.o.f. lever on my Canon f.t.b. is how I learned how depth of field worked. If you have a fast lens like a 50mm f1.8, try the d.o.f. button with that lens.

bkyser Loc: Fly over country in Indiana

SteveR wrote:

I'm not sure why, but when I shot with a film camera using a Canon 50mm (or was it 55?) f1.8 lens I did not have this "darkening" problem that you speak about. However, when using lenses on my D7100 that were not as fast I experienced the same problem that you did. The d.o.f. lever on my Canon f.t.b. is how I learned how depth of field worked. If you have a fast lens like a 50mm f1.8, try the d.o.f. button with that lens.

It depends on if you are shooting wide open. The dimming is because it's actually closing your aperture down to where it's set. Remember, your lens is wide open, until the press of the shutter button, it closes down to whatever you have it set for, then opens back up. If it didn't work that way, a lot of us would HAVE to move to an electronic viewfinder, or just give up photography, because you wouldn't be able to see at F16 to compose your image.

I'm guessing if you didn't see the dimming, it's because you were shooting at 1.8

rmalarz Loc: Tempe, Arizona

I'm not sure the DOF button works unless one is shooting in Aperture priority or manual mode. That would, conceivably be the only time the camera would know the aperture prior to pressing the shutter release.

Since the lack of DOF scales on the modern lenses eliminates knowing the DOF, the preview button is invaluable in determining if what one wants to be in focus is going to be in focus.
--Bob

bkyser wrote:

It depends on if you are shooting wide open. The ... (show quote)

Tallyann

Thank you all for the replies. I'll continue to practice using it and then decide if I find it that helpful.

CaptainC Loc: Colorado, south of Denver

I don't think it is all that helpful considering the image on the LCD is much easier to see and evaluate. I have not used it in 15 years at least.

jcboy3

rmalarz wrote:

Excellent answer, Linda.

I use the DOF preview button on my cameras extensively. That's the best way to know before you expose what will and won't be in focus.
--Bob

I can't tell from that tiny little hole what will be in focus. I can tell if it's out of focus, but I could tell that before pressing the button. I could check the image after taking it, but that requires playing it back, zooming in, moving around. Not worth it. I just rip off a few shots at various apertures and pick the one I like later.

ORpilot Loc: Prineville, Or

By using DOF you can selectively put the subject in focus and select all or none of the foreground or background in focus. Just centering on the subject and using various apertures is hit and miss. Buy using DOF helps you learn and understand how your equipment works in harmony by adjusting, aperture along with focus point and lens choice. Happy shooting