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Comment by l33tbro | Hacker News Reader

My pet-peeve with modern DSLR's is that none of these manufacturers seem to care about motion-cadence with their video offering. There's been amazing leaps with 4k video and now 10 bit image depth with the Panasonic GH5, but the footage looks so damn robotic and souless compared to cinema cameras from Arri and Red.

I obviously don't expect a $2000 dslr to match a $50k Alexa in image quality, but surely they must be able to make the motion of the images smoother and less CCTV looking.

Blackmagic put out an amazing little pocket camera a few years ago with gorgeous colours and buttery smooth motion, why can't the big guys follow suit?

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I think a lot of the problems relate to the experience of the person behind the camera.

Often you can see the choppiness when things are moving. That to me looks like they are using a high shutter speed which is inappropriate for cine work. In still photography if you take a picture of a waterfall on a bright day at 1/1000 you'll see every crisp drop, shooting at 1/30th will give a little bit of smoothing motion blur. Using a DSLR shooting at 25 frames a second and leaving the shutter speed on auto can result in a sequence of 1/1000 second shots which will look choppy. What they should be doing is using Neutral Density filters so they can choose the appropriate aperture for the shot whilst keeping the shutter speed at 1/30 or there abouts. This will give the smoother motion images but does take skill and time.

My other bugbear is many cameramen appear to have forgotten what a tripod is. The camera wobbling about can occasionally add to the atmosphere but most of the time it is just annoying and distracting. Again a combination of lack of skill and production values.

> My other bugbear is many cameramen appear to have forgotten what a tripod is. The camera wobbling about can occasionally at to the atmosphere but most of the time it is just annoying and distracting. Again a combination of lack of skill and production values.

With projection and home displays lagging camera technology, I'd be surprised if the opposite didn't happen. You can do a lot of shake reduction with 2x the pixels you intend to keep.

Also I think a lot of the shake these days is added in post, partly to cover for production flaws and partly to add "atmosphere" as you say.

It's not camera shake creating blurry images I'm talking about, it's the cameraman 'wobbling' about so the image isn't steady. The images will still be sharp, just the camera moving about a bit.

Ah, you mean displacing rather than rotating, yes, I see what you mean, there's no way to correct that perspective shift.

Though perhaps with two cameras and/or some grid projection...

> Also I think a lot of the shake these days is added in post

That's easy to check; if there is no parallax then it was definitely added in post.

Maybe someone here can answer my question:

During panning shots (horizontal, vertical), in recent films the image is blurry and uncomfortable (for me). Similar panning shots in earlier films seem cripser and more "comfortable".

Is there a technical reason (shutter speed fashion) ? Or is it in my head ?

http://www.red.com/learn/red-101/global-rolling-shutter

Interesting looking article, thank you & I'll read that later.

An example of a different shutter mechanism producing an odd effect, this picture https://www.flickr.com/photos/sorenragsdale/3192314056/ shows that what the camera sees isn't always the truth!

There are really nice video explanations for rolling shutter effects on very fast things by Smarter Every Day[1] and standupmaths[2].

[1] https://www.youtube.com/watch?v=dNVtMmLlnoE

[2] https://www.youtube.com/watch?v=nP1elMR5qjc

It's called 'Rolling Shutter'. This was never a problem until the advent of using CMOS sensors for motion recording. It basically started with the Canon 5D and iPhone video.

As a camera operator, this crap technology gave me my first gray hairs. It allows for the processor and write tech in the camera to only handle one line of pixels at a time instead of the entire frame. In response, camera departments had to invent the term 'Global Shutter' to describe the proper way to do it, in which the entire frame is captured at once.

There is always https://photo.stackexchange.com/ too :-)

Using an ND filter to get a slower shutter speed is the way to go. The more expensive cameras usually have a ND filter built in. Shooting at 24fps is possible on most modern cameras these days.

If you want to have the ability to adjust the amount of blur in post shooting at 120fps+ allows for that workflow but it’s a pain to do.

Or is it something else like a bad video codec?

It's more to do with the way motion is captured by the sensor than shutter rates, ND or applying motion blur. Someone else posted an article about global-vs-rolling shutter, which gets to the heart of that jittery video look common to CMOS sensors found on DSLRs.

Also, in film, people generally keep the shutter angle at 180 degrees. So for 24 frames per second, the shutter speed is usually 1/48 of a second.

As for codecs, that's actually where some of these cameras are making leaps and bounds. The GH5 I mentioned is capable of 10 bit recording, which means you could record ProRes HQ with an external recorder.

I've got the Blackmagic pocket. I'd say the main difference is being able to shoot raw video. It's just like butter in grading compared to 8bit video. And their colour science is good.

I think we'll have h265 10bit video in most cameras (and mobile phones) pretty soon, and that will be a marked improvement in terms of colour and dynamic range of video footage.

Some higher end Sony and Canon dSLR's shoot raw video, but I guess it's generally a niche feature, most people wouldn't want to shoot or edit raw video.

Wouldn't you think that's the global shutter of the camera? Raw definitely helps with pushing the image in colour grading, but I always thought the nice motion cadence on the BMPCC comes from the fact that the global shutter scans the entire image at once when capturing a frame, which makes it more filmic and less jittery than rolling shutter sensors which scan a series of parts of the image to create the frame.

The BMPCC has a rolling shutter. Some other Blackmagic cameras have global shutter. I don't personally think there is a huge difference unless you're doing fast camera movement`

I think the video quality is down to reasonably high dynamic range sensor, and RAW sequence capture, meaning you can actually access all that dynamic range

I thought they added a switchable global shutter mode, no? Maybe i'm getting it confused with another model. Probably!

I'm only now looking into DSLR's for a low-light option. Funnily enough, the ones that stand out to me are the Samsung NX1 and the Fuji XT2. Samsung oddly has great motion cadence, but awful macro-blocking. Fuji, unsurprisingly, has beautiful colours. Unfortunately both are only 8 bit, which is kind of a deal-breaker for me.

As an aside, how rare and cool to get to geek out on Hacker News over this stuff!

Sony A7r ii is the low light king, there is a new version due in the next couple of months.

I am not going to be buying another camera with 8bit video, so will be holding out until there are more 10bit options out there. HEVC has a 10bit profile and it will be everywhere because of HDR TV's and phones, but might take a year or two to get popular in cameras.

It's amazing in low-light, but I find the colours are pretty washed out and the image can band pretty bad once you apply post processing to get it looking half decent. That's been my experience with it anyway. Didn't know they have a new model - great to hear.

To learn about what you're calling "shakiness", look up 'rolling shutter'. It's a way of processing only one row of pixels at a time. CMOS sensors all have this problem. They are able to have much cheaper and slower processors in cameras this way but he result is garbage and nobody notices except people like myself who worked in camera department and operator, and even many of them didn't understand.

Only after a decade of trash CMOS sensors are people starting to realize that cameras did not get exponentially better overnighy. They got worse.

Even RED cameras use these CMoS sensors, albeit very fast ones. Alexas have proper global shutters along with most Blackmagic cameras.

There's not much to capturing motion besides shutter speed and frame rate. Mostly the latter.

Rolling shutter aside, given the same settings, there should be no real differences between Arri, Red and those DSLRs in motion capture (and not in image depth, dynamic range, resolution, and color science), and I don't think there are.

All kinds of movie, TV and documentary work use high end DSLRs from Canon and co, and the motion is just fine.

Of course the idea is that motion is usually set to 24fps in both those cameras and Arri, Red etc. If you want "smooth" motion of the hi-fps variety, jack up the fps. But then it would be soap-opera like and not what most people associate with cinematic motion.

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