Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-19-2010, 03:55 AM   #31
Pentaxian




Join Date: Sep 2006
Location: Kaunas
Posts: 1,452
Well, 8 frames continuous shooting (i.e. one second only) at low ISO does not seem good either

10-19-2010, 03:59 AM   #32
Loyal Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 15,744
QuoteOriginally posted by Steelski Quote
Lets look at this a bit more logically, If the issue arrives at 6400 then its possible to just shoot 3200 and push process later. It would not be recommended for 12800 and above, but 3200 to 6400 should not be much of a problem.
Falconeye has said that if you shoot in RAW you may actually be better shooting at iso 1600 or 3200, underexposing and pushing the photo in post processing. That is all the camera is doing. Truthfully, I think it is pretty amazing that it can do that as fast as it can, considering how long it takes me on my dual core computer to open K7 RAW files and adjust settings on them.
10-19-2010, 03:59 AM - 1 Like   #33
Veteran Member
dgaies's Avatar

Join Date: Oct 2009
Location: Maryland / Washington DC
Posts: 3,917
QuoteOriginally posted by Vaikis_ Quote
what SD cards you use for measurments ? Please use LexarŽ Professional 133x - it's very fast card
I was using a SanDisk Extreme III., so I don't think speed was the issue.

I also agree with the other posters that suggested this is not really a card speed issue but more of a processing bottle neck. I notice it just shooting single high-iso shots when it takes 1-2 seconds for the preview on the rear LCD to show up.

One other thing to keep in mind is that the size of the RAW files, for the same shot content, varies quite a bit. For the test image I shot (the one with the toy dragon, car and medicine bottle), the RAW file size was as follows:

K5__0991_iso100.DNG 18.41 MB
K5__0992_iso200.DNG 19.68 MB
K5__0993_iso400.DNG 21.44 MB
K5__0994_iso800.DNG 23.14 MB
K5__0995_iso1600.DNG 25.40 MB
K5__0996_iso3200.DNG 26.44 MB
K5__0997_iso6400.DNG 28.96 MB
K5__0998_iso12800.DNG 31.63 MB
K5__0999_iso25600.DNG 32.70 MB
K5__1000_iso51200.DNG 32.71 MB

So I'm sure this is also a large factor in how many shots can be taken before the buffer fills.
10-19-2010, 04:23 AM   #34
Veteran Member
Steelski's Avatar

Join Date: Jan 2008
Location: Varna
Posts: 468
QuoteOriginally posted by dgaies Quote
I was using a SanDisk Extreme III., so I don't think speed was the issue.

I also agree with the other posters that suggested this is not really a card speed issue but more of a processing bottle neck. I notice it just shooting single high-iso shots when it takes 1-2 seconds for the preview on the rear LCD to show up.

One other thing to keep in mind is that the size of the RAW files, for the same shot content, varies quite a bit. For the test image I shot (the one with the toy dragon, car and medicine bottle), the RAW file size was as follows:

K5__0991_iso100.DNG 18.41 MB
K5__0992_iso200.DNG 19.68 MB
K5__0993_iso400.DNG 21.44 MB
K5__0994_iso800.DNG 23.14 MB
K5__0995_iso1600.DNG 25.40 MB
K5__0996_iso3200.DNG 26.44 MB
K5__0997_iso6400.DNG 28.96 MB
K5__0998_iso12800.DNG 31.63 MB
K5__0999_iso25600.DNG 32.70 MB
K5__1000_iso51200.DNG 32.71 MB

So I'm sure this is also a large factor in how many shots can be taken before the buffer fills.
Could you do something for me if possible.
If you shoot a static scene, at ISO 1600 and underexpose by 4 stops. The same scene at 3200 underexposed by 3 stops, 6400 underexposed by 2 stops, 12800 underexposed by 1 stop, and one at 25600 exposed properly.
It would be very interesting to see how much info can be extracted from the underexposed shots. If they have NR, and how that affects the buffer.

EDIT:
I would be willing to host the files. or provide results.

10-19-2010, 04:30 AM   #35
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,752
This discussion seems a tempest in a tea-pot.

How many pro sports photographers shoot high-fps RAW? None that I have ever heard of. JPG has always given better fps and also quicker output turnaround too. In this regard the fps results in shooting JPG with the K-5 (25 or so in the buffer) seem perfectly respectable, especially when the camera settings are tuned for action (disable corrections etc).

Just compare the K-5 with the D7000 for a second. The D7000 says it fits about 31 Fine JPG's and only between 10-15 RAW files (depending on 12/14 bit etc) in the buffer. That's not a whole lot different from the K-5.

And just as with the D7000, if you want more JPG's in the K-5 buffer, set the JPG quality one notch lower and you will probably get three times more images in the buffer and smoother faster fps.
10-19-2010, 04:36 AM   #36
Senior Member




Join Date: Oct 2010
Location: Adelaide, Australia
Photos: Albums
Posts: 251
QuoteOriginally posted by dgaies Quote
K5__0991_iso100.DNG 18.41 MB K5__0992_iso200.DNG 19.68 MB K5__0993_iso400.DNG 21.44 MB K5__0994_iso800.DNG 23.14 MB K5__0995_iso1600.DNG 25.40 MB K5__0996_iso3200.DNG 26.44 MB K5__0997_iso6400.DNG 28.96 MB K5__0998_iso12800.DNG 31.63 MB K5__0999_iso25600.DNG 32.70 MB K5__1000_iso51200.DNG 32.71 MB
Wow! 14MB of noise!!! That's nearly half the file size!!!!
10-19-2010, 04:37 AM   #37
Veteran Member
dgaies's Avatar

Join Date: Oct 2009
Location: Maryland / Washington DC
Posts: 3,917
QuoteOriginally posted by rawr Quote
This discussion seems a tempest in a tea-pot.

How many pro sports photographers shoot high-fps RAW? None that I have ever heard of. JPG has always given better fps and also quicker output turnaround too. In this regard the fps results in shooting JPG with the K-5 (25 or so in the buffer) seem perfectly respectable, especially when the camera settings are tuned for action (disable corrections etc).

Just compare the K-5 with the D7000 for a second. The D7000 says it fits about 31 Fine JPG's and only between 10-15 RAW files (depending on 12/14 bit etc) in the buffer. That's not a whole lot different from the K-5.

And just as with the D7000, if you want more JPG's in the K-5 buffer, set the JPG quality one notch lower and you will probably get three times more images in the buffer and smoother faster fps.
I think the surprise here was that at high iso, I was only getting 6-7 JPG (instead of 4 RAW) before it slowed down. I just would have expected better results when shooting JPG.
10-19-2010, 04:39 AM   #38
Veteran Member




Join Date: Dec 2007
Posts: 923
Most people I know who are drive mode users use JPEG out of camera.
If you have a few hundred drive-mode shots and have to meet an editor or client's deadline, you are unlikely to be working a RAW file.

Of course, to each his own....some people do want the be able to work the best out of their drive-mode images, and their choice would be RAW shots.

10-19-2010, 04:40 AM   #39
Veteran Member
dgaies's Avatar

Join Date: Oct 2009
Location: Maryland / Washington DC
Posts: 3,917
QuoteOriginally posted by Steelski Quote
Could you do something for me if possible.
If you shoot a static scene, at ISO 1600 and underexpose by 4 stops. The same scene at 3200 underexposed by 3 stops, 6400 underexposed by 2 stops, 12800 underexposed by 1 stop, and one at 25600 exposed properly.
It would be very interesting to see how much info can be extracted from the underexposed shots. If they have NR, and how that affects the buffer.

EDIT:
I would be willing to host the files. or provide results.
Yes, I would be glad to take those for you, but unfortunately I probably won't get to it until later today as I am taking my son on his field trip this morning and then I may (or may) not bother popping into work for the afternoon. If I don't (which is most probably), I might be able to get to them after lunch.
10-19-2010, 04:42 AM   #40
Ash
Community Manager
Loyal Site Supporter
Ash's Avatar

Join Date: Mar 2007
Location: Toowoomba, Queensland
Photos: Gallery | Albums
Posts: 22,687
True, and a good observation there. There has to be some limitation to buffer size, and with 8 images of at least 20Mb each, that's a decent sized buffer. Nevertheless, as disappointing as the drive mode limitation sounds, practically speaking it's not all that restrictive in most genres of photography, and if it comes to the crunch when sports or action shots need to be continuously driven through for a few seconds, perhaps set a USER mode to JPG shooting at high fps and there's an instant dial set for action ready to go at the flip of a switch.
10-19-2010, 04:43 AM   #41
Veteran Member
Steelski's Avatar

Join Date: Jan 2008
Location: Varna
Posts: 468
QuoteOriginally posted by dgaies Quote
Yes, I would be glad to take those for you, but unfortunately I probably won't get to it until later today as I am taking my son on his field trip this morning and then I may (or may) not bother popping into work for the afternoon. If I don't (which is most probably), I might be able to get to them after lunch.
I would not worry too much about this. There is no rush. I gather you are only shooting DNG still.
10-19-2010, 04:43 AM   #42
Pentaxian
JohnBee's Avatar

Join Date: Sep 2008
Location: front of computer
Posts: 4,620
QuoteOriginally posted by Rondec Quote
Falconeye has said that if you shoot in RAW you may actually be better shooting at iso 1600 or 3200, underexposing and pushing the photo in post processing. That is all the camera is doing. Truthfully, I think it is pretty amazing that it can do that as fast as it can, considering how long it takes me on my dual core computer to open K7 RAW files and adjust settings on them.
I said this before and I'll say it again...
As interesting as this sounds, how to we compose our scenes with black frames?
It doesn't seem very practical.
Or am I totally missing something here?
10-19-2010, 04:45 AM   #43
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,752
An addendum to my post above: the D7000 results have this fineprint against their buffer figures that is useful to note:
Reliability/Operability - Nikon D7000 | Nikon

Maximum number of exposures that can be stored in memory buffer at ISO 100. Drops if Optimal quality is selected for JPEG compression or long exposure noise reduction is on.

Figures assume JPEG compression is set to Size priority. Selecting Optimal quality increases the file size of JPEG images; number of images and buffer capacity drop accordingly.
10-19-2010, 04:50 AM   #44
Loyal Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 15,744
QuoteOriginally posted by JohnBee Quote
I said this before and I'll say it again...
As interesting as this sounds, how to we compose our scenes with black frames?
It doesn't seem very practical.
Or am I totally missing something here?
Well, you just have to trust your eyes I suppose. If you can't actually see the scene, then your camera will struggle. Obviously in film days this is exactly what we did. Folks that use the K200 and older cameras do this as well, since high iso capabilities are pretty rudimentary on those cameras. Still, Marc Sabatella has posted some quite nice underexposed concert shots that he pushed in post. Clearly it isn't ideal, but it can be done.
10-19-2010, 04:51 AM   #45
Senior Member




Join Date: Oct 2010
Location: Adelaide, Australia
Photos: Albums
Posts: 251
I agree with those who are saying that it's not the card speed but in-camera processing. If it is true that the highest "native" ISO is 6400 (or 1600? someone please verify. I can't find the original article I saw this in...), then the higher ISO settings are all done in post-processing by the processor, which means bumping up the EV and applying NR. I would assume the two (EV and NR) are closely linked, so i'd be surprised if a new firmware comes out that "fixes" it by making the NR optional.

Also, if it is the case that the highest native ISO is 6400, then we should be able to get exactly the same results from a computer-NR-processed image taken at 6400 as one out of the camera at 51200. Can someone verify this?

So the only real advantage to shooting higher ISO than the native is less time on the computer and more in the field?
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-5, k-5 ii, k-5 iis, k5, pentax k-5
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K7 Buffer Issue? samholton Pentax DSLR Discussion 4 01-08-2010 07:19 AM
K-7 40 jpeg buffer enough? Pentaxor Pentax DSLR Discussion 5 06-28-2009 01:28 PM
K100D Super Buffer? res3567 Pentax DSLR Discussion 7 05-10-2009 05:13 AM
Buffer Write Speed of the K10d ruemiser Pentax DSLR Discussion 5 12-30-2007 09:41 AM
Loving the buffer size - K10D!! photo_mom Pentax DSLR Discussion 27 12-10-2006 06:32 PM



All times are GMT -7. The time now is 05:02 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