Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
06-02-2009, 06:29 AM   #1
New Member

Join Date: May 2009
Location: Murrieta, CA
Photos: Gallery
Posts: 19
DOF Preview

Hi. I'm new to photography and looking at a few different cameras. What is DOF preview and how do you use it? This is one of the options I'm comparing. Thanks!

06-02-2009, 06:35 AM   #2
Veteran Member

Join Date: Apr 2008
Location: Minnesota
Photos: Gallery
Posts: 1,530
By using hte DOF preview you get to see how your aperture settings effec Depth of Field without having to take a shot and then look at it after it is written to your memory card. It is quicker than taking a shot looking at it, deleting it and adjusting it as you need.
06-02-2009, 06:40 AM   #3
Moderator Emeritus

Join Date: May 2007
Location: Edmonton Alberta, Canada
Photos: Gallery | Albums
Posts: 10,648
(Depth Of Field) DOF preview is used to 'stop the lens down' before taking a picture. Aperture is the variable opening inside the lens that controls light transmission and DOF.

The lens is (assuming a modern automatic lens) always focused wide open so the viewfinder is nice and bright and the focus lock is fast. So if you were to select f8 on an f1.4 lens, the camera will meter the scene with the lens wide open (at f1.4) but calculate what the meter reading is for f8. The lens only stops down mechanically to f8 during the split second the shutter button is pressed. If it didn't work this way, focus would be slow or not at all and the viewfinder would be too dark to see through. But the problem is, you can't tell what the effect of an f8 setting is on the DOF because the lens is always wide open.

So on a Pentax the DOF preview is a lever that allows you to stop the lens down to your selected aperture setting so you can see the effect of the aperture on the DOF. Great tool especially in creative photography and macro shots.
06-02-2009, 10:22 AM   #4
Senior Member

Join Date: May 2009
Location: Eastern TN
Posts: 266
Great answer, Peter! Succinct but sufficient!

06-02-2009, 11:52 AM   #5
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
As far as I'm concerned, actually getting a DOF preview is not all that important to me - given that the viewfinder darkens, and it' not *100%* accurate anyhow (the focus screen alters things in some case), I'd just as soon take the picture and look at the LCD.

However, I consider DOF preview an indispensible feature on a Pentax DSLR anyhow, because it happens to be the only way to get the camera to display the meter reading with a manual exposure lens. You can press a button to get the camera to set an appropriate shutter speed for you, but I prefer actually *seeing* the meter reading in the viewfinder, and that only happens while doing a DOF preview.

Not an issue if you don't use manual lenses often, or if you're comfortable with the "semi-automatic" exposure mode of pressing a button to set shutter speed (eg, if you normally use Av mode with modern lenses). But for someone who really uses manual lenses and manual exposure modes a lot, a Pentax camera without DOF preview is pretty severely crippled. For other camera brands, there may be other issues; DOF preview may have nothing to do with metering. So what I'm saying only applies when comapring pentax DSLR's.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dof, pentax help, photography, preview
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
How does DOF preview function? Heldur Pentax Film SLR Discussion 11 10-20-2008 10:29 AM
DOF preview problem Pusiek Pentax DSLR Discussion 4 09-04-2008 02:05 PM
DOF Preview Button Bubbabob Pentax Film SLR Discussion 2 06-22-2008 10:41 PM
DOF preview not working madisonphotogrl Pentax DSLR Discussion 6 03-21-2008 06:32 AM
k20 dof preview bimjo Pentax DSLR Discussion 3 03-14-2008 05:03 PM

All times are GMT -7. The time now is 05:56 AM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]