Sony HDR-CX900

Phil Lee · March 31st, 2014, 01:20 PM

Hi

Quote:

Originally Posted by Cliff Totten

I can absolutely confirm that shooting in 4k and scaling down to 1080 creates SPECTACULAR "HD" videos.

A "typical" HD camera will resolve maybe 700-800 lines. A "really good" 3 sensor HD camera can resolve up to 800-900 lines (realistically)

The AX100 shoots much, much higher resolution than that. When scaled down to "HD", that video could easily reach the maximum 1080 lines of resolution. It pegs the 1080 limitation meter right to the very last last pixel. Your 4:2:0 4k now becomes 4:2:2 (4:4:4?) HD and has the absolute maximum pixel density. It's sad for me to think that my AX100's downscaled 4K to 1080 image now makes my EX1r native 1080 image look...."soft".

Plus, you have the benefit of being able zoom/crop a 1080 window and move it around your 4K space for framing.

It's a no brainer for me. The AX100 is WELL worth the extra $500 over the CX900.

I do need to warn you though, this 4K stuff is highly addictive. I have only been doing it for 6 days now and I'm already completely addicted to it....be very careful. Don't let it get the best of you. (As it has already done with me)

CT

The irony is due to the long hold up times of LCD and OLED displays the resolution chart when seen as a moving object at just 24fps/30fps will be not much better than 1080P at 60fps.

I can't watch this 24fps 4K footage without feeling ill, it isn't shot like film so the slow frame rate is very evident and just presents itself to me as a very fast slide show, I see 24 individual images a second and rarely does it look like fluid motion. This is a known problem with 24fps, especially when shot and shown as video, and I think we have an element of the emperors new cloths here and people are somewhat ignoring the obvious issues. Search the Internet, the limitations and issues are well know, but now suddenly 24fps is great, I'm sorry but I don't understand the hype of this consumer 4K format.

The Big Judder Problem and the Overhyping of 24p
Is 24p judder really this bad??
Frame rate - Wikipedia, the free encyclopedia
24p Judder & The Most Cost Effective Models To Tame It?
GH2 Stutter/Judder/Strobe issues discussion - Personal View Talks
An interesting 24p Judder solution...
What is 1080p24? - CNET
TweakGuides.com - A Guide to HDTVs

When 4K is at 60fps I'm buying it, but not before, and people need to be aware of the limitations these 1st generation consumer 4K camcorders come with. Going back to low YouTube type frame rates just so the hardware can struggle to capture 4K at high compression levels is not something I'm willing to fork out on, and others my feel the same and wish to know the compromises these early devices are making.

If someone wants to capture what will be recognised next year as poor quality 4K footage just because it looks good at 1080P despite the low frame rates, then that is everyone's own choice to make, but lets at least acknowledge the short comings so people can make an informed decision.

24fps/30fps does not belong as a 4K video format. The UHD standard doesn't specify 30fps as a recognised frame-rate, for video it starts at 60fps with an eye firmly on delivering 120fps. UHD includes 24fps and 25fps for legacy reasons only, should a 4K camcorder costing a not inconsiderable amount of money to most consumers be stuck in the past in only offering legacy 4K capture?

Regards

Phil

Jon Fairhurst · March 31st, 2014, 02:26 PM

Phil,

I think that saying 24 fps is obsolete is a bit like saying that shadows are obsolete because we can't see the details in the shadows.

Certainly, news, and reality-based content, 50 or 60 fps is great. For sports, 100 or 120 fps or faster would be wonderful. But for narrative material the 24 fps has its place. It's not going away.

Note that there's a problem when you shoot with a shutter time less than 1/100 in 50 Hz countries or 1/120 in 60 Hz countries - you'll get flicker from lights, especially fluorescent lights. At 100 or 120, you need a 100% shutter to avoid flicker. (Okay, you could shoot 200 or 240 if you sync the frame rate and sample when the lights are at their peaks, but now you start to fight signal to noise.)

With narrative film, we hide things. We build false sets in sound stages. Our actors put on costumes and wear makeup. Scripts are written to hide character intent. Shallow DOF hides details that are off plane. Grading obscures real colors. Framing hides content outside of view. Shadows hide things in the view. And 24 fps hides details in time.

It's no accident. Imagine a scene with, say, 6fps and extreme motion blur. You could use this as an effect to portray an affected reality or altered state of consciousness. Speed this up to 24 fps and 1/48 and the altered reality is on the cusp of being transparent. Things look real but somehow slightly not real. It's like being in and out of a dream. Speed things up to 120 fps or so and things start to look more like real, waking life.

Personally, I wish that our systems allowed truly dynamic frame rates. One could then show fast frame rates for a hyper-fight with the character on amphetamines. Then slow to 24 fps for drama. The TV within the scene plays at 60 fps. The character starts drinking and the frame rate slows from 24, 23, 22...

Regardless of the technical measurements, frame rate and shutter speeds are artistic choices.

And if somebody wants the 24 fps look, a 24 fps camera is all they need.

Jon Fairhurst · March 31st, 2014, 02:43 PM

Quote:

Originally Posted by Phil Lee

The UHD standard doesn't specify 30fps as a recognised frame-rate, for video it starts at 60fps with an eye firmly on delivering 120fps. UHD includes 24fps and 25fps for legacy reasons only, should a 4K camcorder costing a not inconsiderable amount of money to most consumers be stuck in the past in only offering legacy 4K capture?

FWIW, SMPTE ST 2036-1 includes 24/1.001, 24, 25, 30/1.001, 50, 60/1.001, 60, and 120 fps for UHDTV. (Some proponents would like to add 100 and 120/1.001 fps.) There's no asterisk near 24 fps saying that it's for legacy use only.

This said, if you want to shoot at higher frame rates, go for it! Shoot at the rate that fulfills your vision. And if you buy a UHD TV that supports 60 fps, that would set you up for future UHD sports broadcasts. On the other hand, if you watch films - and that's the primary UHD content today - and don't watch sports, a 24/30 fps UHDTV will do the trick.

Cliff Totten · March 31st, 2014, 05:28 PM

Having 4K (or UHD) at 60p is a nice thing to have, no doubt.

For me, back in the days when I was shooting 1920x1080, (just last week) my normal frame rate was 29.97p. I have my EX1r, FS100 and NX70 all set for 30p.

Like many people here, I HATE 24p as well. But 30p? I think it looks like "film" without the judder. 30p also slices into 60i for Blu Ray perfectly. I'm a big believer in 30p to 60i - PSF

So for me, I'm perfectly happy with the AX100 shooting 30p. Correct me if I'm wrong but there aren't many "true" 4K 60p displays out there right now. (or even "true" 60 HD either...HDMI 1.4 cant even carry it today) Web-YouTube and even Netflix 4k are only 30p. (Fro NetFlix, I'm not 100% sure but I'm fairly certain of this.)

The AX100's 30p looks great to me and when bounced down to HD, it still looks crazy amazing.

The best thing to do is get yourself a direct 4K file form the AX100 and evaluate that. YouTube's 4k judders under motion pretty heavily. I suspect their stream uses a VERY long GOP structure. Rather than use a key frame every 15, it looks like they double the length and spread out the I frames to lighten the CODEC.

It's funny. Before I got the AX100, in my mind, I have all these ideas that this camera was mostly a toy. I got it anyway to play with 4K today and invest big next year. After a few days of shooting and TONS of zoomed in playback and pixel peeping the crap out of this footage, I was shocked at how good it actually is. (200-300% zommed in 1080 crops)

Trust me, this camera is much better in the real world than it really should be. It defies the numbers. Yes, 60 Mbp/s 30p on paper sounds weak. Surprisingly, it's pretty damn good. As hard as I wanted to dismiss it, this camera has won me over...but only AFTER I started using it for 5 days.

Get ahold of some direct recordings, then see what you think.

CT

Dave Blackhurst · March 31st, 2014, 05:34 PM

I don't think anyone has been "thrilled" about the 30p limitation, in fact it's been heavily discussed in advance of the release of the AX100...

BUT, the footage coming in does not look bad. I can't stand to shoot 24p, because it does look jerky, BUT if this camera manages to keep it smooth looking enough, as seems to be the case, I will gladly "fiddle" with the 4K output for the price - and that high bitrate 1080/60p is always there if need be, not aware of ANY other 1080/60p camera at this price and bitrate...

I often render out to 24p, just to reduce file sizes, and it's always looked fine to me, so as much as I would prefer 60p, I'll give 30p a shot... so far the video looks good enough, even with some motion in the frames...

Yes, next year they may well have 60p 4K...but by then I'll at least have some time working with the footage and 4K, and if there's something "so much better", I can upgrade or use the thing as a B cam.

Wacharapong Chiowanich · March 31st, 2014, 08:33 PM

Quote:

Originally Posted by Jon Fairhurst

And if somebody wants the 24 fps look, a 24 fps camera is all they need.

Jon, I think most of the hatred for 24p viewing outside of analogue projection theaters comes from seeing the pulldown judder as opposed to the slowness of the true 24p framerate in traditional film based acquisition and projection. In the old days, when we watched movies at the theaters, we saw or noticed most of the intended effects you mention but definitely not the uneven pulldown sequence of frame playback on the digital computer monitors we now see.

In video, when we talk about watching something at "24p" on our computer displays, this 24p content mostly originates in either true 24p, 23.96 or 60i with 3:2 pulldown. Even if you have a true 24p content, when it was played back on the monitor (not frame interpolation HDTVs), it is never perfectly in sync with the typical monitor's refresh rates which are normally in the range of 50 Hz to 60Hz to accommodate viewing by users in both NTSC and PAL areas. Maybe some mega-buck monitors can do 48 Hz or 96 Hz but most consumers are not likely to have one of these.

Ignoring the camera handling skills required to shoot 24p or 23.96 to best tame the juddering effects, this mismatching of image acquisition/viewing pipeline partly as a result of the legacy interlace video standards makes evaluation of attributes like motion very hard to judge.

David Johns · April 1st, 2014, 09:56 AM

Quote:

Originally Posted by Dave Blackhurst

The AX100 ... will ALSO shoot high bitrate 1080/60p

I believe the CX900 also shoots the high bitrate (50Mbps) 1080/50p (60p US) XAVC-S

Cheers
Dave

Dave Blackhurst · April 1st, 2014, 12:19 PM

yes, the point being that the AX100 will do everything the CX900 will do, including high bitrate 1080/60p... with the added 4K capability.

Ken Ross · April 1st, 2014, 05:07 PM

Quote:

Originally Posted by Cliff Totten

The AX100's 30p looks great to me and when bounced down to HD, it still looks crazy amazing.

The best thing to do is get yourself a direct 4K file form the AX100 and evaluate that. YouTube's 4k judders under motion pretty heavily. I suspect their stream uses a VERY long GOP structure. Rather than use a key frame every 15, it looks like they double the length and spread out the I frames to lighten the CODEC.

It's funny. Before I got the AX100, in my mind, I have all these ideas that this camera was mostly a toy. I got it anyway to play with 4K today and invest big next year. After a few days of shooting and TONS of zoomed in playback and pixel peeping the crap out of this footage, I was shocked at how good it actually is. (200-300% zommed in 1080 crops)

Trust me, this camera is much better in the real world than it really should be. It defies the numbers. Yes, 60 Mbp/s 30p on paper sounds weak. Surprisingly, it's pretty damn good. As hard as I wanted to dismiss it, this camera has won me over...but only AFTER I started using it for 5 days.

Get ahold of some direct recordings, then see what you think.

CT

Cliff, trust me on this, you will never in 3 lifetimes convince Phil that the AX100 is anything but a piece of garbage. He goes from forum to forum throwing bombs at the camera in almost every thread you can find on the subject of video.

The fact that in some respects (resolution & sharpness) it outperformed a BMC 4K camera or that it actually graded well with the BM so that you could intercut the two, just doesn't interest him.

He likes 60p and so do I, but that doesn't make the AX100 anything less than a truly excellent 4K camera that, as you say, performs shockingly well. I've had the pleasure of seeing it on a really large screen UHD TV and that was a treat. :)

Paul Cronin · April 2nd, 2014, 07:13 AM

Well said Ken,

That makes it better to let rants go. After all this forum is about learning and sharing.

Johnny Tieu · April 5th, 2014, 10:09 AM

Here is my Sony HDR-CX900 test :

Dave Blackhurst · April 5th, 2014, 01:31 PM

As nice as that looks, very comparable to what the RX10 produces... somehow the 4K of the AX100 is a little more like looking through a window.

Much appreciate the clip, the 1080/60p does look nice!

Phil Lee · April 6th, 2014, 04:25 AM

Hi

Quote:

Originally Posted by Johnny Tieu

Here is my Sony HDR-CX900 test : Sony HDR CX900 Footage - YouTube

Thanks for the clip. Any chance you can upload this to Vimeo so we can download the original at 60fps, unfortunately YouTube converts to 30fps of course and re-compresses.

Regards

Phil

Dennis Freeman · April 26th, 2014, 12:23 PM

Has anyone seen a comparison of the 1080p video shot with the CX900 with the 1080p shot with the AX100. According to the specs, the Ax100 will shoot 1080p, but is there a significant difference in quality, or none at all. If they were the same, then getting the AX and shooting in 1080 would future proof the camcorder for future use.
Just a thought, incase anyone knows.
Denny

Dave Blackhurst · April 26th, 2014, 02:46 PM

As far as we can tell from the specs, the AX100 adds 4K and a couple minor (or major, depending on how important they are to you) additional features. Otherwise the cameras are nearly identical, both shoot higher bitrate 1080 60p than prior "Handycam class" cameras. I can't see any reason that the "HD" output should be any different in those comparable modes.

Of course with 4K it's possible to downconvert to 1080. Some are getting good results with this approach.

The only question is whether the extra $500 is worth it to have the additional capability. I'd rather have the 4K option and also be able to shoot high bitrate 1080 60p.

March 31st, 2014, 02:26 PM	#17
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Re: Sony HDR-CX900 Phil, I think that saying 24 fps is obsolete is a bit like saying that shadows are obsolete because we can't see the details in the shadows. Certainly, news, and reality-based content, 50 or 60 fps is great. For sports, 100 or 120 fps or faster would be wonderful. But for narrative material the 24 fps has its place. It's not going away. Note that there's a problem when you shoot with a shutter time less than 1/100 in 50 Hz countries or 1/120 in 60 Hz countries - you'll get flicker from lights, especially fluorescent lights. At 100 or 120, you need a 100% shutter to avoid flicker. (Okay, you could shoot 200 or 240 if you sync the frame rate and sample when the lights are at their peaks, but now you start to fight signal to noise.) With narrative film, we hide things. We build false sets in sound stages. Our actors put on costumes and wear makeup. Scripts are written to hide character intent. Shallow DOF hides details that are off plane. Grading obscures real colors. Framing hides content outside of view. Shadows hide things in the view. And 24 fps hides details in time. It's no accident. Imagine a scene with, say, 6fps and extreme motion blur. You could use this as an effect to portray an affected reality or altered state of consciousness. Speed this up to 24 fps and 1/48 and the altered reality is on the cusp of being transparent. Things look real but somehow slightly not real. It's like being in and out of a dream. Speed things up to 120 fps or so and things start to look more like real, waking life. Personally, I wish that our systems allowed truly dynamic frame rates. One could then show fast frame rates for a hyper-fight with the character on amphetamines. Then slow to 24 fps for drama. The TV within the scene plays at 60 fps. The character starts drinking and the frame rate slows from 24, 23, 22... Regardless of the technical measurements, frame rate and shutter speeds are artistic choices. And if somebody wants the 24 fps look, a 24 fps camera is all they need. __________________ Jon Fairhurst

March 31st, 2014, 05:28 PM	#19
Cliff Totten Trustee Join Date: Aug 2010 Location: Florida Posts: 1,197	Re: Sony HDR-CX900 Having 4K (or UHD) at 60p is a nice thing to have, no doubt. For me, back in the days when I was shooting 1920x1080, (just last week) my normal frame rate was 29.97p. I have my EX1r, FS100 and NX70 all set for 30p. Like many people here, I HATE 24p as well. But 30p? I think it looks like "film" without the judder. 30p also slices into 60i for Blu Ray perfectly. I'm a big believer in 30p to 60i - PSF So for me, I'm perfectly happy with the AX100 shooting 30p. Correct me if I'm wrong but there aren't many "true" 4K 60p displays out there right now. (or even "true" 60 HD either...HDMI 1.4 cant even carry it today) Web-YouTube and even Netflix 4k are only 30p. (Fro NetFlix, I'm not 100% sure but I'm fairly certain of this.) The AX100's 30p looks great to me and when bounced down to HD, it still looks crazy amazing. The best thing to do is get yourself a direct 4K file form the AX100 and evaluate that. YouTube's 4k judders under motion pretty heavily. I suspect their stream uses a VERY long GOP structure. Rather than use a key frame every 15, it looks like they double the length and spread out the I frames to lighten the CODEC. It's funny. Before I got the AX100, in my mind, I have all these ideas that this camera was mostly a toy. I got it anyway to play with 4K today and invest big next year. After a few days of shooting and TONS of zoomed in playback and pixel peeping the crap out of this footage, I was shocked at how good it actually is. (200-300% zommed in 1080 crops) Trust me, this camera is much better in the real world than it really should be. It defies the numbers. Yes, 60 Mbp/s 30p on paper sounds weak. Surprisingly, it's pretty damn good. As hard as I wanted to dismiss it, this camera has won me over...but only AFTER I started using it for 5 days. Get ahold of some direct recordings, then see what you think. CT

March 31st, 2014, 05:34 PM	#20
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	Re: Sony HDR-CX900 I don't think anyone has been "thrilled" about the 30p limitation, in fact it's been heavily discussed in advance of the release of the AX100... BUT, the footage coming in does not look bad. I can't stand to shoot 24p, because it does look jerky, BUT if this camera manages to keep it smooth looking enough, as seems to be the case, I will gladly "fiddle" with the 4K output for the price - and that high bitrate 1080/60p is always there if need be, not aware of ANY other 1080/60p camera at this price and bitrate... I often render out to 24p, just to reduce file sizes, and it's always looked fine to me, so as much as I would prefer 60p, I'll give 30p a shot... so far the video looks good enough, even with some motion in the frames... Yes, next year they may well have 60p 4K...but by then I'll at least have some time working with the footage and 4K, and if there's something "so much better", I can upgrade or use the thing as a B cam.

April 1st, 2014, 12:19 PM	#23
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	Re: Sony HDR-CX900 yes, the point being that the AX100 will do everything the CX900 will do, including high bitrate 1080/60p... with the added 4K capability.

April 2nd, 2014, 07:13 AM	#25
Paul Cronin Inner Circle Join Date: Dec 2005 Location: Rhode Island Posts: 4,048	Re: Sony HDR-CX900 Well said Ken, That makes it better to let rants go. After all this forum is about learning and sharing. __________________ Paul Cronin www.paulcroninstudios.com

April 5th, 2014, 10:09 AM	#26
Johnny Tieu New Boot Join Date: Feb 2010 Location: Westminster, CA Posts: 7	Re: Sony HDR-CX900 Here is my Sony HDR-CX900 test : Sony HDR CX900 Footage - YouTube

April 5th, 2014, 01:31 PM	#27
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	Re: Sony HDR-CX900 As nice as that looks, very comparable to what the RX10 produces... somehow the 4K of the AX100 is a little more like looking through a window. Much appreciate the clip, the 1080/60p does look nice!

April 26th, 2014, 12:23 PM	#29
Dennis Freeman Regular Crew Join Date: Nov 2011 Location: West Bloomfield, MI Posts: 42	Re: Sony HDR-CX900 Has anyone seen a comparison of the 1080p video shot with the CX900 with the 1080p shot with the AX100. According to the specs, the Ax100 will shoot 1080p, but is there a significant difference in quality, or none at all. If they were the same, then getting the AX and shooting in 1080 would future proof the camcorder for future use. Just a thought, incase anyone knows. Denny

April 26th, 2014, 02:46 PM	#30
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	Re: Sony HDR-CX900 As far as we can tell from the specs, the AX100 adds 4K and a couple minor (or major, depending on how important they are to you) additional features. Otherwise the cameras are nearly identical, both shoot higher bitrate 1080 60p than prior "Handycam class" cameras. I can't see any reason that the "HD" output should be any different in those comparable modes. Of course with 4K it's possible to downconvert to 1080. Some are getting good results with this approach. The only question is whether the extra $500 is worth it to have the additional capability. I'd rather have the 4K option and also be able to shoot high bitrate 1080 60p.