Quality of K-7 video

Slugger · 07-08-2009, 10:33 PM

I'll say again Joe, you just made Pentax a sale with this video.

sixstring · 07-08-2009, 11:25 PM

Originally posted by falconeye

Great movie, Jim!

I found that you need some light at night. I.e., moon light alone is not sufficient

Thanx. Yeah you will need some light for sure. this one pushed the k-7 to its limits, but this was intented.

Quote:

thanks, but that flickr effect on the gas lights...damn...all the more reason to need manual shutter speeds.

Seeing is beliving ;-) i told you. i hope pentax will do a firmwareupdate to help us with this problem...

jogiba · 07-09-2009, 08:48 AM

Here is another video but with my 85mm F1.4 @F8.
YouTube - Pentax K-7 with 85mm F1.4 Rokinon

**kmccanta** · 07-09-2009, 09:30 AM

Originally posted by Psynema

thanks, but that flickr effect on the gas lights...damn...all the more reason to need manual shutter speeds.

Originally posted by falconeye

+1
Maybe, this use case can convince Pentax to add it. After all, with aperture control being already in, it should be straightforward to do.

So can you help me understand what I am seeing in these clips? The motion looks jerky... is this the frame rate being too low? or the shutter speed too high?

Or... maybe I am catching on here... its the shutter speed being too high for the frame rate.... I didnt understand Psynema's previous comments on Tv/Frame rate ... now I think I get it. These would look smoother if the shutter speed was slower, adding motion blur to each frame. OR if the frame rate was higher to "interpolate" the motion between frames by adding more frames.

Did I catch on?

-k

Psynema · 07-09-2009, 09:49 AM

Originally posted by kmccanta

So can you help me understand what I am seeing in these clips? The motion looks jerky... is this the frame rate being too low? or the shutter speed too high?

Or... maybe I am catching on here... its the shutter speed being too high for the frame rate.... I didnt understand Psynema's previous comments on Tv/Frame rate ... now I think I get it. These would look smoother if the shutter speed was slower, adding motion blur to each frame. OR if the frame rate was higher to "interpolate" the motion between frames by adding more frames.

Did I catch on?

-k

Something like that

1. If you look at Sixstrings low light clip, the flourescent/gas lights in the city FLICKER LIKE CRAZY...a slower shutter speed will help alleviate that. What's happening is the auto shutter is too fast and is catching the light while it's not pulsating since some lights aren't continuous, but rather cycle on and off (we don't see it in real life since our eyes shutter speeds are on the slow side vs. what a DSLR can do).

2. Slow shutter would also help with the aliasing (pixelated contours) problem in 1536 by 1024 mode.

3. I hope to god someone can hack this camera's firmware.

falconeye · 07-09-2009, 10:46 AM

Originally posted by Psynema

a slower shutter speed will help alleviate that.

IMHO, this is only half the answer...

At night, the K-7 will shoot video at slowest shutter speed anyway, which most likely is very close to 1/30s.

In the US, night videos won't flicker.

But in Europe, everything is on 50Hz. So, to make the flicker invisible, you have to capture one or two or four full cycles, translating into 1/25, 1/50, 1/100s shutter speeds.

At 1/30s, you get flicker from an effect called "beat" in acoustics, cf. Beat (acoustics) - Wikipedia, the free encyclopedia

Psynema · 07-09-2009, 10:58 AM

Originally posted by falconeye

IMHO, this is only half the answer...

At night, the K-7 will shoot video at slowest shutter speed anyway, which most likely is very close to 1/30s.

In the US, night videos won't flicker.

But in Europe, everything is on 50Hz. So, to make the flicker invisible, you have to capture one or two or four full cycles, translating into 1/25, 1/50, 1/100s shutter speeds.

At 1/30s, you get flicker from an effect called "beat" in acoustics, cf. Beat (acoustics) - Wikipedia, the free encyclopedia

ah figured it was a europe thing to LOL. Good to know.

Anyone heard if Pentax has ANY plans at updating video features via firmware yet?

Can't be too farfetched...all three of Nikon, Canon, and Panasonic caved to firmware requests for their video DSLRs.

Psynema · 07-09-2009, 05:19 PM

SPECIAL REQUEST!

I've seen the DA2.8 zoom in action...

Anyone have 77mm or 31mm limited footagee?

jogiba · 07-09-2009, 05:53 PM

Originally posted by Slugger

I'll say again Joe, you just made Pentax a sale with this video.

1536x1024 *** mode looks even better.
YouTube - Pentax K-7 with 15mm F2.8 Sigma in 1536x1024 *** mode at Minimum Focusing Distance 15cm/5.9 in.

Psynema · 07-09-2009, 07:10 PM

Originally posted by jogiba

1536x1024 *** mode looks even better.
YouTube - Pentax K-7 with 15mm F2.8 Sigma in 1536x1024 *** mode at Minimum Focusing Distance 15cm/5.9 in.

What is *** mode? I'm assuming that's the highest data rate?

Do you have aliasing problems with *** in full res?

jogiba · 07-10-2009, 04:54 AM

Originally posted by Psynema

What is *** mode? I'm assuming that's the highest data rate?

Do you have aliasing problems with *** in full res?

I only viewed the videos so far on my 17" laptop with 1440x900 display mode and the 1536x1024 *** mode videos look sharper and have not seen aliasing problems. I will use my 2.26Ghz Core 2 Duo 2009 Mac Mini with 4GB DDR3 RAM and Nvidia 9400m graphic chip with my 47" 1080p HDTV in 1920x1080 mode later today to get a better view. Yes 1536x1024 *** is highest data rate.

nostatic · 07-10-2009, 08:35 AM

Originally posted by Psynema

SPECIAL REQUEST!

I've seen the DA2.8 zoom in action...

Anyone have 77mm or 31mm limited footagee?

I will by tonight if things go right...

nixcamic · 07-10-2009, 10:36 AM

Just to clear this up now that final cameras are out, is the video 30fps or 29.97? How long can you actually record on a not to hot out summer day?

Psynema · 07-10-2009, 11:56 AM

Originally posted by nixcamic

Just to clear this up now that final cameras are out, is the video 30fps or 29.97? How long can you actually record on a not to hot out summer day?

it's 30p... if you put the footage in 29.97 you'll get bad aliasing (which I think is a tiny bit of the problem, as people aren't setting their timelines right and in the right codec, then complain).

According to that chart, 7 minutes in change at full quality and resolution

PS - ANY UPDATES ON OVERHEATING issues previously mentioned about a week/two weeks back?

IE - can you have a full day of recording with this thing I hope LOL.

Psynema · 07-10-2009, 12:01 PM

Originally posted by jogiba

I only viewed the videos so far on my 17" laptop with 1440x900 display mode and the 1536x1024 *** mode videos look sharper and have not seen aliasing problems. I will use my 2.26Ghz Core 2 Duo 2009 Mac Mini with 4GB DDR3 RAM and Nvidia 9400m graphic chip with my 47" 1080p HDTV in 1920x1080 mode later today to get a better view. Yes 1536x1024 *** is highest data rate.

Nice, let me know how the uprezzed footage looks to you.

So in FULL RES MODE

*** = 72Mbs

** = 52 Mbs

* = 36 Mbs

And all three rates are very generous IMO

IN 720 P MODE

*** = 56 Mbs
** = 40Mbs
* = 26Mbs

And in SD mode...ah who cares about SD mode LOL.

07-09-2009, 05:53 PM	#759
jogiba Banned Join Date: Sep 2006 Location: Millstone,NJ Posts: 6,491	1536x1024 * mode Originally posted by Slugger I'll say again Joe, you just made Pentax a sale with this video. 1536x1024 * mode looks even better. YouTube - Pentax K-7 with 15mm F2.8 Sigma in 1536x1024 *** mode at Minimum Focusing Distance 15cm/5.9 in.

07-10-2009, 04:54 AM	#761
jogiba Banned Join Date: Sep 2006 Location: Millstone,NJ Posts: 6,491	Originally posted by Psynema What is * mode? I'm assuming that's the highest data rate? Do you have aliasing problems with * in full res? I only viewed the videos so far on my 17" laptop with 1440x900 display mode and the 1536x1024 * mode videos look sharper and have not seen aliasing problems. I will use my 2.26Ghz Core 2 Duo 2009 Mac Mini with 4GB DDR3 RAM and Nvidia 9400m graphic chip with my 47" 1080p HDTV in 1920x1080 mode later today to get a better view. Yes 1536x1024 * is highest data rate. Last edited by jogiba; 07-10-2009 at 09:39 AM.

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07-08-2009, 10:33 PM	#751
Slugger Forum Member Join Date: Apr 2009 Location: Vancouver Island Posts: 77	I'll say again Joe, you just made Pentax a sale with this video.

07-08-2009, 11:25 PM	#752
sixstring Inactive Account Join Date: Mar 2008 Location: Earth Posts: 29	Originally posted by falconeye Great movie, Jim! I found that you need some light at night. I.e., moon light alone is not sufficient Thanx. Yeah you will need some light for sure. this one pushed the k-7 to its limits, but this was intented. Quote: thanks, but that flickr effect on the gas lights...damn...all the more reason to need manual shutter speeds. Seeing is beliving ;-) i told you. i hope pentax will do a firmwareupdate to help us with this problem...

07-09-2009, 08:48 AM	#753
jogiba Banned Join Date: Sep 2006 Location: Millstone,NJ Posts: 6,491	Here is another video but with my 85mm F1.4 @F8. YouTube - Pentax K-7 with 85mm F1.4 Rokinon

07-09-2009, 09:30 AM	#754
kmccanta Site Supporter Join Date: Nov 2006 Location: Portland, Oregon Photos: Gallery Posts: 218	Originally posted by Psynema thanks, but that flickr effect on the gas lights...damn...all the more reason to need manual shutter speeds. Originally posted by falconeye +1 Maybe, this use case can convince Pentax to add it. After all, with aperture control being already in, it should be straightforward to do. So can you help me understand what I am seeing in these clips? The motion looks jerky... is this the frame rate being too low? or the shutter speed too high? Or... maybe I am catching on here... its the shutter speed being too high for the frame rate.... I didnt understand Psynema's previous comments on Tv/Frame rate ... now I think I get it. These would look smoother if the shutter speed was slower, adding motion blur to each frame. OR if the frame rate was higher to "interpolate" the motion between frames by adding more frames. Did I catch on? -k

07-09-2009, 09:49 AM	#755
Psynema Senior Member Join Date: Jun 2009 Posts: 136	Originally posted by kmccanta So can you help me understand what I am seeing in these clips? The motion looks jerky... is this the frame rate being too low? or the shutter speed too high? Or... maybe I am catching on here... its the shutter speed being too high for the frame rate.... I didnt understand Psynema's previous comments on Tv/Frame rate ... now I think I get it. These would look smoother if the shutter speed was slower, adding motion blur to each frame. OR if the frame rate was higher to "interpolate" the motion between frames by adding more frames. Did I catch on? -k Something like that 1. If you look at Sixstrings low light clip, the flourescent/gas lights in the city FLICKER LIKE CRAZY...a slower shutter speed will help alleviate that. What's happening is the auto shutter is too fast and is catching the light while it's not pulsating since some lights aren't continuous, but rather cycle on and off (we don't see it in real life since our eyes shutter speeds are on the slow side vs. what a DSLR can do). 2. Slow shutter would also help with the aliasing (pixelated contours) problem in 1536 by 1024 mode. 3. I hope to god someone can hack this camera's firmware.

07-09-2009, 10:46 AM	#756
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871 Original Poster	Originally posted by Psynema a slower shutter speed will help alleviate that. IMHO, this is only half the answer... At night, the K-7 will shoot video at slowest shutter speed anyway, which most likely is very close to 1/30s. In the US, night videos won't flicker. But in Europe, everything is on 50Hz. So, to make the flicker invisible, you have to capture one or two or four full cycles, translating into 1/25, 1/50, 1/100s shutter speeds. At 1/30s, you get flicker from an effect called "beat" in acoustics, cf. Beat (acoustics) - Wikipedia, the free encyclopedia

07-09-2009, 10:58 AM	#757
Psynema Senior Member Join Date: Jun 2009 Posts: 136	Originally posted by falconeye IMHO, this is only half the answer... At night, the K-7 will shoot video at slowest shutter speed anyway, which most likely is very close to 1/30s. In the US, night videos won't flicker. But in Europe, everything is on 50Hz. So, to make the flicker invisible, you have to capture one or two or four full cycles, translating into 1/25, 1/50, 1/100s shutter speeds. At 1/30s, you get flicker from an effect called "beat" in acoustics, cf. Beat (acoustics) - Wikipedia, the free encyclopedia ah figured it was a europe thing to LOL. Good to know. Anyone heard if Pentax has ANY plans at updating video features via firmware yet? Can't be too farfetched...all three of Nikon, Canon, and Panasonic caved to firmware requests for their video DSLRs.

07-09-2009, 05:19 PM	#758
Psynema Senior Member Join Date: Jun 2009 Posts: 136	SPECIAL REQUEST! I've seen the DA2.8 zoom in action... Anyone have 77mm or 31mm limited footagee?

07-09-2009, 07:10 PM	#760
Psynema Senior Member Join Date: Jun 2009 Posts: 136	Originally posted by jogiba 1536x1024 * mode looks even better. YouTube - Pentax K-7 with 15mm F2.8 Sigma in 1536x1024 * mode at Minimum Focusing Distance 15cm/5.9 in. What is * mode? I'm assuming that's the highest data rate? Do you have aliasing problems with * in full res?

07-10-2009, 08:35 AM	#762
nostatic Veteran Member Join Date: Feb 2008 Location: socal Photos: Gallery Posts: 1,575	Originally posted by Psynema SPECIAL REQUEST! I've seen the DA2.8 zoom in action... Anyone have 77mm or 31mm limited footagee? I will by tonight if things go right...

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07-10-2009, 10:36 AM	#763
nixcamic Veteran Member Join Date: Jun 2008 Location: Guatemala Posts: 354	Just to clear this up now that final cameras are out, is the video 30fps or 29.97? How long can you actually record on a not to hot out summer day?

07-10-2009, 11:56 AM	#764
Psynema Senior Member Join Date: Jun 2009 Posts: 136	Originally posted by nixcamic Just to clear this up now that final cameras are out, is the video 30fps or 29.97? How long can you actually record on a not to hot out summer day? it's 30p... if you put the footage in 29.97 you'll get bad aliasing (which I think is a tiny bit of the problem, as people aren't setting their timelines right and in the right codec, then complain). According to that chart, 7 minutes in change at full quality and resolution PS - ANY UPDATES ON OVERHEATING issues previously mentioned about a week/two weeks back? IE - can you have a full day of recording with this thing I hope LOL.

07-10-2009, 12:01 PM	#765
Psynema Senior Member Join Date: Jun 2009 Posts: 136	Originally posted by jogiba I only viewed the videos so far on my 17" laptop with 1440x900 display mode and the 1536x1024 * mode videos look sharper and have not seen aliasing problems. I will use my 2.26Ghz Core 2 Duo 2009 Mac Mini with 4GB DDR3 RAM and Nvidia 9400m graphic chip with my 47" 1080p HDTV in 1920x1080 mode later today to get a better view. Yes 1536x1024 * is highest data rate. Nice, let me know how the uprezzed footage looks to you. So in FULL RES MODE * = 72Mbs = 52 Mbs * = 36 Mbs And all three rates are very generous IMO IN 720 P MODE * = 56 Mbs = 40Mbs * = 26Mbs And in SD mode...ah who cares about SD mode LOL.