Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-20-2010, 07:13 AM   #1
Inactive Account




Join Date: Sep 2008
Location: Southeastern USA
Posts: 75
Two questions about k5

Is there any sort of intrinsic hindrance of a 25fps video? Does it readily lend its use in common editing software? any sort of certain loss by having this spec?

I presume the Live View of the K7 makes it into the K5 - is the live view customizable to always come into a greatly magnified live view that can be used as a focusing tool?

I believe I read where some camera is able to do this. Possible on the new Pentax flagship?

09-20-2010, 03:18 PM   #2
Pentaxian
Arpe's Avatar

Join Date: Sep 2006
Location: New Zealand
Photos: Gallery | Albums
Posts: 4,344
Some like 24fps as that's what cinema cameras use. I think it's crap actually, on panning shots it's stuttery and looks awful. 25fps is native to PAL TVs. They should also have 30 (29.97) fps for NTSC TVs too, but it appears they don't.

Yes easily edited by common video editors on your computer.

Can't answer other q's.
09-20-2010, 03:53 PM   #3
Senior Member




Join Date: Sep 2009
Posts: 200
QuoteOriginally posted by Arpe Quote
Some like 24fps as that's what cinema cameras use. I think it's crap actually, on panning shots it's stuttery and looks awful. 25fps is native to PAL TVs. They should also have 30 (29.97) fps for NTSC TVs too, but it appears they don't.

Yes easily edited by common video editors on your computer.
This is completely not true, sorry.
Yes, 25fps is native PAL. It's not any "smoother" than 24fps.
The problem is, outside of cinematic look which is 24fps, that in the US it's easy
to convert 24fps to 30fps (by applying cine-expansion - so called 3:2 pulldown)
but it's pretty much impossible to convert 25fps to 30fps.
It's being done, but it always s@cks.
25fps pretty much s@cks big time for our market.
And no, it's never easy to "edit" those things.
09-20-2010, 04:56 PM   #4
Inactive Account




Join Date: Sep 2008
Location: Southeastern USA
Posts: 75
Original Poster
so apparently video in the k5 is a convenience for casual video shooting...

hmmm ok


I found an answer to my liveview question in the Pentax press kit pdf. It says that LiveView can be used at up to 10X for a focusing aid

I guess that theoretically this camera will manual focus exactly like the K7

Overall it looks like a nice camera to me - maybe one worth giving a lengthy audition while waiting on a FF for a few more months

IQ will determine the threshold for buy/try or not. Is it razor sharp? Does it give great Pentax color and depth? then about moire filters/etc

I figure that by about mid November there should be about 3000 or so shots on flickr and a good number of reviews - enough to judge IQ. I hope it does portraits well - skin tone, sharpness

It does look like with a suitable lens that Pentax will finally be able to step up to serious wildlife and sports shooting. and yes I know some do quite well on the wildlife already with existing models. But have you seen any world class sports from Pentax?

time will tell - and then there's price...

09-20-2010, 05:11 PM   #5
Pentaxian
Arpe's Avatar

Join Date: Sep 2006
Location: New Zealand
Photos: Gallery | Albums
Posts: 4,344
QuoteOriginally posted by andi Quote
Yes, 25fps is native PAL. It's not any "smoother" than 24fps.
How can a higher fps not be smoother?
09-20-2010, 05:14 PM   #6
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
QuoteOriginally posted by Arpe Quote
How can a higher fps not be smoother?
When the difference is trivial? (And, when there's no good way to display it....)
09-20-2010, 05:17 PM   #7
Pentaxian
Arpe's Avatar

Join Date: Sep 2006
Location: New Zealand
Photos: Gallery | Albums
Posts: 4,344
Then that would be not "significantly" or "noticeably" smoother
09-20-2010, 05:35 PM   #8
Senior Member




Join Date: Sep 2009
Posts: 200
Those video things are confusing for many people, don't worry
Look, what you usually call "smooth" is the video footage like an NBA game
shot on video which is interlaced, so you have 50 fields per second (in PAL)
- 2 fields per frame - not 25 progressive frames per second.
It's two times "smoother" than a Hollywood movie transferred from cinema 24fps.
For many people that jittery look is what makes it look like a movie and not video.
There is no practical difference in perception between 24fps and 25fps.
There are several PAL "tricks" to display a 24fps movie on a PAL device in 25fps
in a PAL country. And it's not easy.

But it's very hard to convert 25fps to 24 fps.
You need to loose a frame per sec, so you have a jump. You can't perform
a speed change because you destroy the quality of the perfect frames.
There are some algorithms generating "new" frames, but they all degrade the quality.
Plus you have a big audio issue.

K-5 is clearly made for PAL countries.
It's just seems easy enough to shoot 24fps if your hardware allows 25fps.
Not sure what the problem is.

When Canon 5D II was released with 30fps only, it was a huge revolution
which finally made Canon introduce the fw with 24fps. It was possible.
We'll see...

09-20-2010, 05:47 PM   #9
Senior Member




Join Date: Jul 2009
Location: Croydon Park, Sydney, Australia
Posts: 161
Mattdm - Actually, 25fps is the rate used by most std TVs in the world - which has PAL or uses the same rate French system. Only the US and a couple of other countries use NTSC at the 30/29.97fps rate.

PAL at 25fps for std TV, is 720 x 576 AR (Aspect Ratio), while NTSC at 30fps is 720 x 480 AR.

Perhaps the faster frame rate compensates for the 176 lines difference in vertical resolution.

We've had free-to-air Digital TV broadcasts here in Sydney for about 10 years. It's in 2 levels, std - which is 720 x 576, and HD - which on a std 4:3 AR TV plays "letterboxed" in wider angle - like a DVD played letterboxed. Obviously, on a widescreen TV, it plays fullscreen.

When we get US made DVDs, made for NTSC TVs there, some of our Players, and/or TVs - can "translate" those into PAL hardware playable. Or, we can just convert them from NTSC to PAL, and write them to a blank DVD5 or DVD9, depending on whether they are over 4.3GB or not, for those whose older Players or TVs can't translate NTSC.

We get a lot of US Movies on DVD, that are copied in Thailand, Indonesia, etc, and are available very cheaply in some "bargain" shops here. Usually they are "main movie" only, no extras, and translated into PAL, though some are left in NTSC.

I suppose folk in the US do the same as we do, in reverse, with their translating Players and TVs, to play PAL DVDs from the EU and Australia, so on.

We used to have "Regioning" - US Region-1, Oceania/Australia Region-4, so on, here. But so many people bought the non US-market low-cost Chinese "non-regioned" DVD-Players, that by the time the big Media Corporations realised this, it was far too late to "recall or confiscate" millions of such Players, so the Govt. changed the laws instead. We're now DVD "region free", by law... (That also applies to PC DVD Reader-Burner drives, which is most convenient.)

Regards, Dave.
09-20-2010, 06:10 PM   #10
Senior Member




Join Date: Jul 2009
Location: Croydon Park, Sydney, Australia
Posts: 161
Andi - To covert 24fps video to 25fps, you can use Avidemux. Use the "DVD (lavc)" mode, in the left column of the dialog.

Under "Video > Configure" - choose "2-Pass - Average Bitrate."

Under "Video > Filters" - choose "Transform > Resample FPS". Click on that, and in the popup box that appears, change the "24fps" Avid will have identified, to "25fps". And DO tick the "Blend" check-box there.

You can also convert 24fps to 30fps under "Filters > Interlacing > Pulldown". You will get a better result if you do that large a change while converting the Video to Xvid4 - and apply a very small amount of Sharpen, under "Filters > Sharpness > Msharpen.

Then use the "DVD (lavc)" to create your "Moviename.mpeg(2) DVD compliant file from the Xvid4 file.

With that file, unless using it in an Editor, etc, DVD-Styler will convert it to a DVD-compliant fileset or ISO - or will burn it to DVD for you.

There are free versions of Avidemux and DVD-Styler for Windows and Linux.

Regards, Dave.
09-20-2010, 06:38 PM   #11
Pentaxian
Arpe's Avatar

Join Date: Sep 2006
Location: New Zealand
Photos: Gallery | Albums
Posts: 4,344
QuoteOriginally posted by exwintech Quote
I suppose folk in the US do the same as we do, in reverse, with their translating Players and TVs, to play PAL DVDs from the EU and Australia, so on.
Actually I believe that while it's common for our PAL players to be able to read NTSC, it's quite rare for the reverse to be true. Happy to be corrected though.
09-20-2010, 07:37 PM   #12
Veteran Member
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,209
I don't understand how it's difficult to convert from 25fps to 24fps. European TV do this conversion the other way around (24->25fps) all the time for films. The way of doing it is to accelerate the speed by 4% and normalizing audio. Maybe not a perfect solution but it's no worse than the 3:2 pulldown used to convert from 24fps to NTSC 30fps.

Now, unless it's hardware limited (which I doubt, the Nikon D7000 using the apparently same sensor can do it) it should be trivial to allow 24fps.

It would also be very annoying to mix K-7 video (30fps) with K-x (24fps) then K-5/K-r (25fps).
09-20-2010, 08:41 PM   #13
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
QuoteOriginally posted by Arpe Quote
How can a higher fps not be smoother?
Because of refresh rates and converting it to 30fps or 24fps.

QuoteOriginally posted by ManuH Quote
I don't understand how it's difficult to convert from 25fps to 24fps. European TV do this conversion the other way around (24->25fps) all the time for films. The way of doing it is to accelerate the speed by 4% and normalizing audio. Maybe not a perfect solution but it's no worse than the 3:2 pulldown used to convert from 24fps to NTSC 30fps.

Now, unless it's hardware limited (which I doubt, the Nikon D7000 using the apparently same sensor can do it) it should be trivial to allow 24fps.

It would also be very annoying to mix K-7 video (30fps) with K-x (24fps) then K-5/K-r (25fps).
If you accelerate or decelerate and normalize, well, you get faster or slower playing between regions. I imagine it is annoying to line up and basically you have parallel threads when creating a film if people did it this way.

I agree that it should be trivial to allow 24fps.

Last edited by Eruditass; 09-20-2010 at 08:48 PM.
09-20-2010, 08:57 PM   #14
Veteran Member




Join Date: Aug 2010
Posts: 523
QuoteOriginally posted by ManuH Quote
I don't understand how it's difficult to convert from 25fps to 24fps. European TV do this conversion the other way around (24->25fps) all the time for films. The way of doing it is to accelerate the speed by 4% and normalizing audio. Maybe not a perfect solution but it's no worse than the 3:2 pulldown used to convert from 24fps to NTSC 30fps.

Now, unless it's hardware limited (which I doubt, the Nikon D7000 using the apparently same sensor can do it) it should be trivial to allow 24fps.

It would also be very annoying to mix K-7 video (30fps) with K-x (24fps) then K-5/K-r (25fps).
Do they get a higher voice?
- Solution is easy, dump you K-7 and K-x, go for K-5 & K-r, right?
09-20-2010, 09:09 PM   #15
Forum Member




Join Date: May 2010
Location: Gold Coast, QLD
Posts: 88
QuoteOriginally posted by andi Quote
This is completely not true, sorry.
Yes, 25fps is native PAL. It's not any "smoother" than 24fps.
The problem is, outside of cinematic look which is 24fps, that in the US it's easy
to convert 24fps to 30fps (by applying cine-expansion - so called 3:2 pulldown)
but it's pretty much impossible to convert 25fps to 30fps.
It's being done, but it always s@cks.
25fps pretty much s@cks big time for our market.
And no, it's never easy to "edit" those things.
24p/25p conversion is easy with many NLE's. With Premiere for example, you simply right click on the files, select "interpret footage" and change the frame rate to whatever you want.Whether going from 24p>25p or 25p>24P it's just as easy. It's a 4% speed change but is imperceptible, and leaves no blended or skipped frames. The only time this would cause problems is when shooting multi-cam stuff which needs to be synced.

Once you do this slight speed change you can still add 2:3 pulldown to change to 60i. This is actually a little more difficult as it often involves transcoding, unlike 24p/25p conversion.

The only frame rate which is/was a total disaster for some (everyone but USA & Japan) users is 30p. Doing 25p>24p>60i (30p) can get you perfect results. 30p>25p is pretty much impossible to do smoothly or imperceptibly.

Having said all that it is a shame they didn't include both 24p & 25p.
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!
k5, live, pentax news, pentax rumors, sort, view
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Questions about my new KM Winnie Pentax Film SLR Discussion 25 02-11-2010 06:46 PM
PZ-10 questions Rick in Ohio Pentax Film SLR Discussion 2 08-19-2009 02:28 PM
Going to the US soon, a few questions Duplo Travel, Events, and Groups 7 07-31-2009 03:26 AM
DA 16-45 Questions fccwpe Pentax SLR Lens Discussion 13 06-24-2009 01:51 PM
Few questions Atindra Pentax SLR Lens Discussion 8 06-15-2009 10:26 PM



All times are GMT -7. The time now is 09:15 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