Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
10-26-2013, 03:19 PM - 1 Like   #16
Veteran Member
Col's Avatar

Join Date: Apr 2007
Location: Stansted Essex
Photos: Gallery
Posts: 615
QuoteOriginally posted by Pheo Quote
While we are here, is anyone able to explain to me exactly what autofocus to -3EV actually means.

I'm struggling with the concept of how dark this is?
Exposure value - Wikipedia, the free encyclopedia

Say a landscape lit by a full moon

10-26-2013, 05:17 PM - 2 Likes   #17

Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,852
Original Poster
QuoteOriginally posted by Col Quote
Say a landscape lit by a full moon
Or, as the wikipedia article highlights, an outdoors scene illuminated by a 'bright' Aurora borealis or Aurora australis.

Indoors -3 EV happens a lot when you are shooting live music in dim pubs or venues, for example. Being able to meter down into shadowy darkness, and get focus, will be extremely useful, especially as a lot of venues don't allow flash use.

It also means K-3 users won't have to use the annoying AF assist lamp to help us get focus. I hate the AF assist light, and always have it turned off.
10-27-2013, 05:36 AM   #18
Veteran Member

Join Date: May 2012
Posts: 698
If I calculate right ev-3 is somewhat lower than is possible to shoot handheld unless you go to extreme ISO.

At ISO 6400 you will need 1/4 second at F1.4. For a half decent shutter speed of 1/15 you need to go all the way up to 25,600.

So I would say the AF covers practically any situation where you would think of shooting handheld without flash. The extra sensitivity will still help to achieve quicker and more accurate focus as well as better tolerance of low contrast subjects.

I will no doubt find it useful even for tripod shots as I like low light shooting and focus is often quite a tedious excercise. In some extreme cases I cannot even see the subject so I doubt even the K-3 will help there but in less extreme cases any situation where AF works is going to be a great advantage.

Oddly I have at times managed to focus my K-30 in moonlight, not 100% reliable maybe but quite unexpectedly good. I guess with the K-3 being actually specified to be capable of that it will be as reliable as shooting in daylight.

Last edited by lister6520; 10-27-2013 at 06:51 AM. Reason: Oops - I meant K-30.
10-27-2013, 05:43 AM   #19
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
QuoteOriginally posted by lister6520 Quote
Oddly I have at times managed to focus my K-3 in moonlight, not 100% reliable maybe but quite unexpectedly good. I guess with the K-3 being actually specified to be capable of that it will be as reliable as shooting in daylight.
You have a k-3 ?

10-27-2013, 05:55 AM   #20
Veteran Member

Join Date: Nov 2006
Location: Brighton, United Kingdom
Photos: Gallery
Posts: 311
Thanks, didn't spot that table in Wikipedia when I was looking, must've got distracted and not scrolled down enough!

  • 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!
auto-focus, dslr, ev, exposure, k-3, k3, pentax k-3, pixel, range, rgb, scene, sensor
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Shooting handheld in low light richardstringer Troubleshooting and Beginner Help 22 10-05-2013 08:23 AM
k-30 vs k-5 low light street/city, landscapes and astro Conqueror Pentax DSLR Discussion 8 03-30-2013 02:19 PM
K-x low light shooting help jellyfish26 Troubleshooting and Beginner Help 6 04-20-2011 01:04 PM
Low light shooting w/K100d and smc 50mm f/1.4 cdf Pentax DSLR Discussion 10 10-03-2007 12:09 PM
Hello, and I have some questions about low light shooting strictlypentax Welcomes and Introductions 2 06-02-2007 09:30 AM

All times are GMT -7. The time now is 10:12 PM. | 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]