Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-17-2011, 04:26 PM   #1
Senior Member
sagiboy's Avatar

Join Date: Aug 2009
Location: LI
Posts: 230
The EV button confusion..

How many of us here use the EV button and move the wheel to get the appropriate reading???? I was never serious about it, until i discovered that as you increase it( in Av mode)the shutter value decreases...which i presume is letting the camera let in more light by keeping the shutter open longer...??? Exactly when do u mess with this feature..???? Its also linked to the flash when you activate it....I really can not pinpoint the difference when i bump it or bring it down....pls help...

04-17-2011, 04:51 PM   #2
Site Supporter
SpecialK's Avatar

Join Date: Dec 2006
Location: So California
Photos: Gallery
Posts: 14,428
You use it when most of the subject matter is significantly darker or lighter than a medium tone, which will fool the light meter.

It you are metering off a black locomotive, the camera wants to make it gray. When metering a white cat in the snow, the camera will try to maker it gray.

So, for a really dark subject you need to underexpose to make it dark, and for a really light subject you need to overexpose it to make it bright.
04-17-2011, 04:52 PM   #3
Inactive Account




Join Date: Aug 2008
Location: Michigan, USA
Photos: Gallery | Albums
Posts: 7,485
Well, if you're in Av and you adjust the EV, you are telling the camera that you want to use the same aperture setting but open the shutter longer to let in x number more stops of light. The Flash has it's own exposure compensation that can be selected when you select the type of flash you want to use.

When to use it? I spend most of my time in M mode and don't use EV Compensation. What you are doing is basically the same thing as going to M mode, pressing the green button to center your exposure meter, and then making an adjustment. The difference is, with EV comp in Av, the camera is taking care of that adjustment for you. In Av you also don't have to press the green button, the mode takes care of that step as well.

See This.. The Semi Auto modes (Av and Tv) are doing the same thing when you activate EV Compensation.

04-17-2011, 04:54 PM   #4
Pentaxian




Join Date: Oct 2006
Location: Chicago suburb, IL, USA
Posts: 1,535
Hi sagiboy,

Ev compensation is used to override the Program Line that the camera's metering system is using to either give more or less exposure than the meter deems as correct. With Flash it only works with P-TTL metered flash. If you find that your P-TTL flash is either over or underexposing, you can control it by either using Ev comp (faster) or by using Flash Comp in the flash menu (or both).

In Av, the shutter speed will necessarily be increased since you've specified the aperture, and if ISO is fixed, there is no other way to alter the exposure.

I use it in situations where the meter is easily fooled -- since I shoot birds, I'll give you a bird example. . .

Let's say a bird with a white breast is sitting in a shaded area. If the rest of the frame is also in shade, then the camera's meter will probably be correct. If the bird now moves so it's partially in bright direct sun, the white breast will most likely blow out, and if I want any highlight detail, I've got to tell the camera to underexpose the shot. Without changing anything else, I can dial in - EV comp in the amount that my experience tells me is a good bet. If the bird next flies up and lands on a naked branch and is silhouetted against the sky, it'll be significantly underexposed if I let the camera meter it, so I need to overexpose it to get any detail or color, so I use + Ev comp. I have all the cameras that have programmable e-dials to have the rear dial control the Av and the front dial to control Ev comp just for these kinds of situations.

Scott

04-17-2011, 05:23 PM   #5
Senior Member
sagiboy's Avatar

Join Date: Aug 2009
Location: LI
Posts: 230
Original Poster
You guys are great..!!!! Thanks a ton....
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!
button, ev, pentax help, shutter
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
645D Confusion Joburger Pentax Medium Format 43 01-27-2011 01:13 PM
SDHC Confusion! CeeDee Pentax Camera and Field Accessories 9 03-13-2010 10:08 AM
FA 50/1.4 Confusion - Question twokatmew Pentax SLR Lens Discussion 6 02-20-2010 07:42 PM
Macro confusion....... gsrokmix Troubleshooting and Beginner Help 6 11-26-2009 09:33 PM
M-Mode Green Button M42 mount Confusion... MNCurt-K10D Pentax DSLR Discussion 12 02-08-2008 10:02 PM



All times are GMT -7. The time now is 03:58 PM. | See also: NikonForums.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