Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-24-2009, 08:00 AM   #1
New Member
Riverlady's Avatar

Join Date: Mar 2009
Location: Austin, TX
Photos: Gallery
Posts: 24
K200D exposure bias

In a photo class last weekend we shot a gray card in full sun, I was using the long end (250mm) of my Tamron 18-250 and filled the frame with the card. (AV mode, no exposure comp.) Much to my surprise, the histogram indicated that the camera was overexposing by 0.3 stop. My general feeling after using this camera for about six months now is that generally it tends to underexpose, and that seems to be the consensus from what I've read online. My teacher, who has decades more experience than I, says the bias should be the same no matter what the light, or what lens is on the camera.

So, I am curious to understand this... wondering if maybe the explanation is that more often than not in real life I am metering in difficult situations that have a wide difference in the amount of light in various areas of the scene like mottled shade, mixed sun/shadow with lots of glare (e.g. arroyos) with dynamic range on, which I believe (is this correct?) underexposes in order to protect highlights. Also that even tho the camera may have a +0.3 bias with a gray card, often I am shooting scenes that require compensation for a specific lighting or subject situation that also must be factored in.
Any thoughts?

06-24-2009, 02:10 PM   #2
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
You're really seeing the histogram spike right of center when metering off a gray card that fills the frame? That would be quite unusual.

Even so, how the amera meters gray card has little to do with exposure of real world scenes. I the issue with real world is preciely that it is *not* a gray card, so there is no One True Expousre for an given scene. Sure, the one chosen by the camera is often darker than the one you'd prefer, but that's not "underexposure" per se - that's just the camera not reading your mind.
Reply

Bookmarks
  • 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!
bias, camera, card, dslr, exposure, light, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to display the exposure in the lcd screen for the K200D rustynail925 Pentax DSLR Discussion 7 11-30-2009 11:17 AM
Getting Max Exposure Range in K200D Carolina Mim Pentax DSLR Discussion 3 09-05-2009 07:32 PM
K200D flash exposure problems valhallasw Pentax DSLR Discussion 4 05-13-2009 05:43 PM
PPL/PBL exposure bias relative to other tools wasim_altaf Digital Processing, Software, and Printing 11 05-08-2009 11:23 PM
Exposure bias on Pentax cameras arbutusq Pentax DSLR Discussion 5 11-14-2006 07:36 AM



All times are GMT -7. The time now is 07:07 PM. | See also: NikonForums.com, CanonForums.com 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?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top