Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-05-2009, 07:29 PM   #1
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
K-x burst mode videos

I made some videos of burst mode on the K-x. I found out that JPEG burst mode buffer dependent on both the ISO and what is in the scene, while RAW and RAW+ are limited by write speed of the SDHC interface and doesn't change. Observe:

K-x JPEG ISO200:
YouTube - K x Burst JPEG ISO200

K-x JPEG ISO800:
YouTube - K x Burst JPEG ISO800

K-x JPEG ISO1600:
YouTube - K x Burst JPEG ISO1600

K-x JPEG ISO12800:
YouTube - K x Burst JPEG ISO12800

K-x RAW:
YouTube - K x Burst RAW

K-x RAW+:
YouTube - K x Burst RAW+

The pictures were taken of some kitchen glassware. When I put the lens cap on, at ISO200, I got excess of 40 shots (I'm not trying to kill my shutter life). At ISO12800, I still got 8 or so. So scene limits at lower ISO, hardware processor/amplifier limits at higher ISO. Around 1600 is where it starts to drop below 17 frames.

Noise Reduction: was left on default - starts at 800, and at medium.

File Size: They were all pretty much the same size, around 5 MB - I deleted them but I just took an ISO 200 and ISO 12800 shot in Av mode, same exposure:

200: 5174KB
12800: 5374KB

Now, the buffer sizes between the two came out to be 8 vs 30+. I don't think that played a role.


Last edited by Eruditass; 11-06-2009 at 02:01 PM.
11-05-2009, 07:35 PM   #2
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
Original Poster
Oh and I've gotten over 2000 photos at this point on this charge on my duracell white tops. Btw, many batteries are capable of this if you burst all day long instead of spreading it out over weeks.

Poor K-x shutter.. at least it is rated more than other DSLRs in this range.. 100K?
11-05-2009, 08:12 PM   #3
Veteran Member
er1kksen's Avatar

Join Date: Oct 2008
Location: Staten Island, NY
Photos: Gallery | Albums
Posts: 1,661
Wow, 100K? That's what the 40D I just replaced with a K-x was rated to. Nice to know I'm not downgrading in that respect. I wouldn't worry about running the shutter down.
11-05-2009, 08:28 PM   #4
Veteran Member




Join Date: Jun 2009
Location: on the wall
Photos: Gallery
Posts: 715
This is full size, right? How does it perform if you choose a smaller file size (reduced # of pixels)?

11-05-2009, 08:37 PM   #5
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,576
Yep, 100K, according to the K-x press release:
QuoteQuote:
The K-x also features a more reliable shutter unit, which passed a demanding action test of more than 100,000 shutter releases.
100K plus.

Let's see at 5fps, that means Pentax would have done stuff like run their test camera(s) on a test bench continuously or intermittently for a total of about 333 minutes, or 5 and a half hours, without failure (100,000 actuations/5 ps = 20,000 seconds total duration, then /60). Sounds pretty robust.

I wouldn't buy one of those test cameras 2nd hand though.
11-05-2009, 08:41 PM   #6
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
Original Poster
QuoteOriginally posted by dragonfly Quote
This is full size, right? How does it perform if you choose a smaller file size (reduced # of pixels)?
Yep, full size, 3 star.

Reducing the file size helps very slightly. At 2 MP and 1 star, RAW and RAW+ gain only 1 or 2 shots each, though the speed afterwards is a slight bit faster.

JPEG at ISO 12800 went up to 14 or so. From 12 MP, lowering to 10 and 6 gained a couple shots at ISO 12800. Lowering the star quality gained 1 or 2 over the lowering of the resolution while at 12 MP.

Ok, no more for my poor shutter. These are on 1/2 dead batteries but I did plug in new ones with minimal differences.

edit: these tests were with shadow comp all the way up. The OP tests were with it off. I don't think there is a big difference with that, but highlight comp effectively doubles the ISO so take that into account. No testing with Lens correction - I don't feel like finding a DA lens to put on.
11-05-2009, 09:31 PM   #7
Veteran Member
er1kksen's Avatar

Join Date: Oct 2008
Location: Staten Island, NY
Photos: Gallery | Albums
Posts: 1,661
As long as I can get the full 4.7 fps for about 5 frames in RAW, we're good. Is that how it works?
11-05-2009, 10:01 PM   #8
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
Original Poster
Yep, check out the video. The fps after it fills isn't as horrendously slow as previous models IIRC

11-06-2009, 02:02 PM   #9
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
Original Poster
Did some bursts with NR off, this makes ISO 1600 and below have buffers of somewhere like 30+. However, as I had read.. 3200+ ISO is actually done through software and the buffer size is around 8 even with NR off
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!
burst, camera, dslr, iso, iso12800, iso200, jpeg, k-x, limits, mode, photography, size, youtube
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K-5 burst mode? TrueIndigo Video and Pentax HDSLRs 6 10-16-2010 05:17 AM
Example of K20d burst mode johnmflores Post Your Photos! 5 05-21-2009 07:33 PM
Burst mode Orli Troubleshooting and Beginner Help 3 02-22-2009 06:20 PM
20fps burst videos Tyler Pentax News and Rumors 11 02-04-2008 05:23 PM
Burst Mode shefaet Pentax News and Rumors 42 01-25-2008 08:50 AM



All times are GMT -7. The time now is 07:55 AM. | 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