Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-06-2009, 04:07 AM   #1
Inactive Account




Join Date: Feb 2009
Location: Velence, Hungary
Posts: 664
K-X Autofocus in low light?

Hi Everyone ! Hands on experiences, comments and comparisons are welcomed about this topic.

Thanks

Andras

12-06-2009, 05:51 AM   #2
Junior Member




Join Date: Jul 2009
Location: London
Photos: Gallery
Posts: 42
Much better than my K200D, that's for sure. Of course it depends on the contrast between the subject and the background.
12-06-2009, 09:18 AM   #3
Pentaxian




Join Date: Mar 2009
Location: Perth Australia
Photos: Albums
Posts: 1,511
it can focus in lower light than i can see
12-06-2009, 10:35 AM   #4
Veteran Member




Join Date: Sep 2007
Location: USA
Posts: 1,812
QuoteOriginally posted by planedriver Quote
Hi Everyone ! Hands on experiences, comments and comparisons are welcomed about this topic.
I understand that the Kx has the same AF as the Pentax K7?

If so, then "on paper" it is slower than the current equivalent Canon or Nikon -



crops from Popular Photography tests one of the very few places that actually test AF at different light levels.

As one can see at lower light levels the K7 could take TWICE as long as the Canon or Nikon....

BUT I own and have used the Kx for my shooting which is mainly musicians on stage - and I have found the Kx AF positive and fast enough for my (critical) usage.

But I only use the central AF point and always pre-focus - even when shooting a series - I focus on the face/eye hold re-compose then shoot - even doing that I can get quite a rapid rate of fire.... and have not felt as if the Kx is slowing me down.

EDIT to ADD -

Here are a couple of shots from a club where it was pretty dark -



EXIF re-attached.

rest of album - link to first pic in series -
Picasa Web Albums - UnknownVincent - Last Waltz En...
(25 pics mostly on the Kx 3:2 aspect ratio - any 4:3 aspect ratio are from the Canon G10)

The second shot was at approx 4 foot-candles or 44lux or EV=4 - this is pretty low.


Last edited by UnknownVT; 12-06-2009 at 11:07 AM. Reason: added sample photos
12-06-2009, 12:30 PM   #5
Veteran Member




Join Date: Mar 2007
Location: U.K.
Posts: 685
A test in Feb 2010 Computer Shopper calls the Kx AF fast and the Canon T1i (500D) very inaccurate and they had to use manual focus to get any sharp shots. No D300 unfortunately but that's not really a competitor anyway as it costs more. The D90 sounded about the same as the Kx for speed. No figures unfortunately but they are usually quite thorough in their tests and don't seem biased.

Other tit-bits......
Kx was the lowest noise.

They down-rated the Kx for high premium lens prices and no AF VF points.

One big Kx plus was the fact that the kit lens was the sharpest out of Canon, Nikon, Sony and Olympus, and was almost as good as the 50mm primes of the other manufacturers for detail.

The T1i was amazingly slow at continuous 0.9fps RAW shooting after the buffer filled, the Kx carries on at 2fps (fast cards).

D90 video was not good due to 'lurching' auto exposure and very poor sound, Canon was juddery at 20fps. Kx video was excellent, sound OKish.
12-06-2009, 12:36 PM   #6
Veteran Member




Join Date: Mar 2007
Location: U.K.
Posts: 685
QuoteOriginally posted by WerTicus Quote
it can focus in lower light than i can see
Can it AF on a black cat in a room lit by one low energy bulb? My K100D can't do this to save its life, even with a Sigma flash assist light. No black cats with white patches allowed, must be black
12-06-2009, 12:53 PM   #7
Veteran Member




Join Date: Sep 2007
Location: USA
Posts: 1,812
QuoteOriginally posted by SteveB Quote
A test in Feb 2010 Computer Shopper calls the Kx AF fast and the Canon T1i (500D) very inaccurate and they had to use manual focus to get any sharp shots. No D300 unfortunately but that's not really a competitor anyway as it costs more. The D90 sounded about the same as the Kx for speed. No figures unfortunately but they are usually quite thorough in their tests and don't seem biased.
Nice to read this - however it seems from the majority of reviews out there that the Canon T1i does not appear to have any focusing issues - and since the T1i is such a popular camera there are numerous reviews out there.

However as I said I don't find the Kx slowing me down -
and it is certainly more positive and faster than my K100D

QuoteOriginally posted by SteveB Quote
Kx was the lowest noise.
Again this is general agreement with most findings by users and confirmed with the standardized and consistent test shots on Imaging-Resource -

Of all the APS-C sized sensors I feel the Kx has the best high ISO performance -
and I am astounded by a dSLR of such a reasonable price -
side-by-side comparisons with the test images on the aforementioned Imaging-Resource - the Kx for me was better than the Nikon D300S, D5000 and D90; Canons 7D. T1i


QuoteOriginally posted by SteveB Quote
One big Kx plus was the fact that the kit lens was the sharpest out of Canon, Nikon, Sony and Olympus, and was almost as good as the 50mm primes of the other manufacturers for detail.
This is how I have always felt about the two basic "kit" lenses (the 50-200 is even better) - they give absolutely nothing away in terms of image quality and AF ability when compared to more expensive lenses.

That's always been then reputation of Pentax of having really quality for much less than expected.

I was convinced by Popular Photography's reviews of the Samsung versions of those two lenses:

Lens Test: Schneider-Kreuznach D-Xenon 18-55mm f/3.5-5.6 AF

Lens Test: Schneider-Kreuznach D-Xenon 50-200mm f/4-5.6 AF

Pity they did not include their useful SQF table -
EDIT to ADD
here are scans of the SQF from my copy of the magazine -


Last edited by UnknownVT; 12-06-2009 at 01:14 PM. Reason: added scans of SQF tables
12-07-2009, 07:49 AM   #8
Pentaxian




Join Date: Aug 2007
Photos: Gallery
Posts: 1,563
QuoteOriginally posted by UnknownVT Quote
I understand that the Kx has the same AF as the Pentax K7?

If so, then "on paper" it is slower than the current equivalent Canon or Nikon -



crops from Popular Photography tests one of the very few places that actually test AF at different light levels.

As one can see at lower light levels the K7 could take TWICE as long as the Canon or Nikon....

BUT I own and have used the Kx for my shooting which is mainly musicians on stage - and I have found the Kx AF positive and fast enough for my (critical) usage.

But I only use the central AF point and always pre-focus - even when shooting a series - I focus on the face/eye hold re-compose then shoot - even doing that I can get quite a rapid rate of fire.... and have not felt as if the Kx is slowing me down.
I don't know about test setups versus practical use.
However, I've been shooting wild life in darkness, shoulder to shoulder with 450D and 500D users.
Combined with a DA*6-250mm my K-7 was allways the fastest to lock focus and the most accurate.

If the K-x uses the same AF system, you should not worry...

12-07-2009, 10:42 AM   #9
Pentaxian




Join Date: Mar 2009
Location: Perth Australia
Photos: Albums
Posts: 1,511
QuoteOriginally posted by SteveB Quote
Can it AF on a black cat in a room lit by one low energy bulb? My K100D can't do this to save its life, even with a Sigma flash assist light. No black cats with white patches allowed, must be black
Not sure, i only tested it on a black space cat flying through a black hole in space.
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!
camera, dslr, k-x autofocus, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Best low light autofocus - k20,k7 or KX?? germar Pentax DSLR Discussion 24 07-11-2010 09:22 AM
Do I upgrade my Camera or Lens to get better low light autofocus? lazarustx Pentax DSLR Discussion 21 04-23-2010 05:19 PM
K2000 low light autofocus flash assist - without using flash Eruditass Troubleshooting and Beginner Help 21 08-24-2009 05:33 PM
K20D/K2000 with SDM lens or K7 for low light autofocus? swhang Pentax DSLR Discussion 17 06-21-2009 04:51 AM
Work great for low light autofocus? konraDarnok Pentax Camera and Field Accessories 3 06-25-2008 03:08 PM



All times are GMT -7. The time now is 08:23 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