convince me: The need of 4k video / and high fps rates

Bernard Carns said:

ShootMeAlready said:

osv said:

Stemu said:

most sensors are at least 4k and 1080p video is downscaled.

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no, dedicated 1080p cameras do not have 4k sensors, because it's way too expensive.

perhaps what you are thinking of is pixel binning, which is the process of combining adjacent pixels into one pixel.

the gh4 has a 4k sensor, and it can't capture the full 1080p resolution, it's done by ~800 lines... you have to acquire in 4k and downrezz to get the full 1080p rez out of the gh4.

Bernard Carns said:

The problem is that due to lack of processing power the "downscaling" is done quick and dirty and not optimal way. Expensive big movie cameras have this power and they produce beatiful 1080 video.

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expensive big movie cameras have expensive big sensors, that's why they produce nice video.

--
dan

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And big sensors require big processing power. Especially if they are to shoot raw, or prores flavours, MP4 or is it H265? At 60fps or is it 120fps? And if they squeeze in the big sensor with the big processing they generate big heat. And thats what is truly lacking today, is cooling in DSLR form factor. The design does lend itself to raw video, for lengthy shots. - JMHO

--
"Shoot Long and Prosper"

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"And big megapixels require big processing power".

It has nothing to do with sensor size.

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I did not say big "sensor size". Big is measured in terns of how much it has to process off the sensor, it may be 14 bit raw or 10bit raw for instance. Or it may be 12Mpix to 36Mpix, but its the overall throughput that has to be big.

Bernard Carns said:

Big processing does generate heat.

When I shoot RAW with my BMPC the SSD is almost too hot to touch after an hour. Some people put duct tape on the drives to make a flap so they can pull them out. Even the cage can get almost too hot to touch. And it has a peltier cooling and a fan.

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Interesting.

Bernard Carns said:

But the thing is that people who want RAW video really don't care about the DSLR form factor anyway.

If it were such a big deal to do high end video in a DSLR form factor the 1DC would sell like hotcakes.

It doesn't.

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Actually 5D MkII/III have been used a lot in film because of their form factor (they're small and can be tucked away or get at weird angles a bigger epic cant for instance). Some aps-c canon DSLRs were used in the movie Black Swan. I dont think DSLR are used for raw video that much. With the ursa mini 4k starting at $3k I would not bother with a DSLR for raw shooting.

Bernard Carns said:

People in that budget are buying C100-C500 cameras.

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Again the BMD ursa mini $3k may force a big price drop ~ JMHO

Bernard Carns said:

How much heat do cameras that output RAW video to an external device generate?

How much heat does a BMPCC generate when it's shooting RAW?

What SLR mfg is going to put a peltier cooler and a fan in a DSLR?

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I wish they would put fans in DSLRs, so they could shoot longer exposures at higher ISO.

Bernard Carns said:

BC

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--
"Shoot Long and Prosper"

I just took a gander at B&H's listing for Professional Camcorders. Prices for this kind of gear are $3,500, $5,000, and up. I think I saw only one 4K (maybe two).

For most of us, the good argument for 4K is that apparently it reduces down to a true 1920 X 1080 while most of our HD gear puts out only about 800 (instead of 1080). I do not understand how technically it is cneaper to record at 4K, and reduce to 1080 than it is to produce a fully capable 1080 camera to begin with.

Perhaps those professional, expensive cameras can put out a true 1080, and of course they have capabilities and features for broadcast and other professional requirements that most of us have no need for.

But itis still notable that the overwhelming standard for those professional camcorders is 1920 X 1080.

Richard Frederick said:

I just took a gander at B&H's listing for Professional Camcorders. Prices for this kind of gear are $3,500, $5,000, and up. I think I saw only one 4K (maybe two).

For most of us, the good argument for 4K is that apparently it reduces down to a true 1920 X 1080 while most of our HD gear puts out only about 800 (instead of 1080). I do not understand how technically it is cneaper to record at 4K, and reduce to 1080 than it is to produce a fully capable 1080 camera to begin with.

Perhaps those professional, expensive cameras can put out a true 1080, and of course they have capabilities and features for broadcast and other professional requirements that most of us have no need for.

But itis still notable that the overwhelming standard for those professional camcorders is 1920 X 1080.

--
**** Frederick

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Every Bayer pattern camera including stills gets only about 80% resolution.

There are exceptions for example, no AA filter and pixel shift.

So a 20mp still camera is really only 16.

Nobody is complaining that.

Only gearheads really care that we're getting only 800 lines and not 1080.

In the meantime people who want to make movies are out taking them.

BC

And look at Netflix and Amazon growing list of 4K titles.

once hooked on 4k, 1080 becmes unwatchable.

GodSpeaks said:

Thorfinn said:

Convince me!

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Why should I, or anyone else, 'convice' you? Based upon what you wrote, you are already convinced that you do not need 4K.

Fine, done and dusted.

When the time arrives, you will convince yourself that you need it. Until then, enjoy what you currently have.

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The OP is already convinced. And if he really wanted to hear some feedback on this subject, he would have returned and followed up on his post.

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rialcnis said:

And look at Netflix and Amazon growing list of 4K titles.

once hooked on 4k, 1080 becmes unwatchable.

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Just how big a screen that you can get from Sony for $1000.

I think that to fully appreciate 4k one would want to get at least a 65 inch TV, like Vesku has.

A 49 inch screen would be too small, in my opinion.

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I agree. 55" TV is too little for 4k. I hardly see any difference between good FullHD and 4k unless watching 50 cm away. Also, often too sharp video is distracting if there are any problems with footage like shake, focus breathing, uneven lens.

But the best thing with 4k TV is that pixels are so small that you don't see them. In FullHD TV you can see the individual pixels when looking quite close.

"For most of us, the good argument for 4K is that apparently it reduces down to a true 1920 X 1080 while most of our HD gear puts out only about 800 (instead of 1080)."

In couple of years we will talk: the good argument for 8K is that apparently it reduces down to a true 3840*2160 while most of our 4k gear puts out only about 1600 (instead of 2160).

Everyone complains stolen lines!

Some people make not video, but they talk

about "technical shortcomings" (for filling Internet

... and provoke yawning )

Thanks everybody for a lively debate. Thanks for the idea to shoot 4k and render to HD. I will give that a try. And thanks everybody, discussing the issiue of the ability to recognize the difference of 1080 vs 4k on 1,2 m diagonal screens at a distance > 2,5 m.

When adressing streaming services, I realy like their ability to change the compression and resolution during streaming. Really amazing: 3 people watching 3 different streams over 1 LTE connection @ 160 km/h with all handovers and fallback to 3G. Works fine on the small screens, for Teenage series and sports. Cineastic is different.

None of you named effects like bending & colour depth. I am disapointed of the colours in AVCHD / H.264 compression of my Olympus cameras, compared to their stills. That is why i gave the BlackMagicDesign a try - When watching on Plasma (720p only) it was amazing what it produced. On a cheap LCD the difference between 4:2:2 and H.264 was hardly noticeable.

So thanks again. I think i have to invest in a BlackMagic (and storage, storage, storage) or something compareable, rather than spending a "surplus" price for 4k on my new camera.

Thorfinn said:

I still not see the point in 4k and high framerates beyond scientific and technical documentary and surveillance. Is 4k jut "the new black" like 3D was a decade ago?

Convince me!

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All true, however, I have noticed a very visible improvement when DownRes 4k to 1080P30.

I am also very interested in using 1080P120 for critiquing my bowling swing and will find out if the A7sII internal codec is as poor as it is for the A7s for 720P120 today.

lancespring said:

rialcnis said:

And look at Netflix and Amazon growing list of 4K titles.

once hooked on 4k, 1080 becmes unwatchable.

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.

Just how big a screen that you can get from Sony for $1000.

I think that to fully appreciate 4k one would want to get at least a 65 inch TV, like Vesku has.

A 49 inch screen would be too small, in my opinion.

.

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I bought the 49 inch Sony and it is large and perfect. The 4k is fantastic.

the biggest advantage of one this size is for use as a computer monitor with HDMI, if larger, it's too difficult to use as a computer monitor. My last set was too large. 49 inch is perfect for dual use.

If you are doing life-like video and not fiction then 60fps is very helpful.

The 24fps cuts down on the realistic perception which allows it to bypass the input as real perception and go directly to an experience. It leaps over the first step.

If you try to record fiction with life-like precision it looks fake because you can't because your brain knows it isn't real life. That is why you record with less precision and then your brain doesn't think it is looking at fiction.

We may see exceptions to this in the future. Also, one could of course use high frame rate for either slow-motion or play it back in real-time as a special effect to look more real for some artistic reason.