Michael1

I think if you just look at the marketing materials and consumer trends of the 5MP days and compare them with what is going on today you will realize only now are a great many consumers content with 18-24mp.

Most consumers are content with stills and video they are getting out of their smart phones, and look at what they shoot at best on a computer screen.  I thought the discussion on this forum was at a level higher than that of "a great many consumers" (you would think so, anyway, just based on the price of the equipment discussed).

Michael

Isnt the GH4's 4k really 1080?

CMOS sensors have RGBG arrays. 2:1:1 ratio RGB effectively halves resolution.

By downscaling a 4k file, the image is truer to how much detail the sensor captures.

It isn't in the exact ratio of two to one, because the processing pulls out luminance information out of all the color channels.  Resolution tests are conducted with black and white images, so they do not take into account chroma resolution or chroma artifacts.

Reviewed.com measured the GH4's 4K video resolution in good light at 975 lph (line picture heights) horizontal and 1100 lph vertical, essentially what 1080 resolution is.  You may get higher resolutions than this with a better lenses.  A GH3  measured at 850/825, which is far above most other 1080 DSLRs, and at a level of a top level camcorder.  Most DSLRs are 600-700 lph, and in low light, even lower.

So 4K out of a GH4 is going to look super sharp downsampled to 1080, because most cameras and content delivery systems can't produce images at full 1080 resolution.

BTW, a lot of great posts in this thread. :)

Michael

Panasonic should do GH4s with pure 4K res sensor ( I asume that would be 8Mpix sensor)

Why?  Then they don't have something that appeals to the stills shooters.  What they have now has 1:1 pixel mapping for video anyway.

Michael

I tried grading "Arizona falls" (higher contrast, saturation, different WB) in Resolve and it looks very nice (thought I don't have much experience in grading). On first sight the noise in shadows does not look worse than GH4 4K flat profile graded and scaled to HD - I tried Philip Bloom's Seoul panorama files.

Don't have big screen to pixel peep, so maybe I'm wrong..

Any link?

Michael

Nikon is uselles for video and it will stay uselles, i hope they die as a company at some point, photography tools have reached a point where nobody wants to upgrade, a 20-24 mp sensor is enough and from here there is litttle to no imporvement in DSLR's

I think people were saying this about 5MP sensors not that long ago.

As long as there are debayers, there will be a demand for high MP sensors, even for video.

Michael

Interesting video.  A lot of shots saved by grading.  I would have liked to have seen what Std would have looked like graded for comparison.

Michael

Really looks like s...t

Compared to what? :rolleyes:   Example videos please.

Michael

I have heard of some people doing a firmware update on the lens to correct this.

Michael

According to the specs, the battery life for video on A7s is around  90 min. . This is same as Black magic camera where battery isn't even swabable. 5D III averages around 90 minutes per battery for video too  

In the real world, they have been getting even less, while on the GH4, they have been getting more than the specs.

Michael

I have to think that Nikon's marketing team saw that the Panasonic GH4 has been a runaway success, and they want to get in on the action.  Panasonic is backordered on the GH4. The engineering of the D810 was done before Panasonic released the GH4, so they were stuck with what they had.   If you look at the reviews of the GH4 on B&H Photo, they got 5 stars from over 50 people, with only two people giving it a 4 star.  This is in about a month.  That's unbelievable.  Obviously, good video features means something to a lot of buyers now.

Michael

It does full sensor readout at then properly downsamples it to 1080P. This was all covered extensively at NAB by newshooters,com in interviews with Sony and other reviews. 

 

There is no way in hell D810 will match A7s video quality. I would be surprised if it can even match RX100 III (or GH3) 

"No way in hell"?  Is this before or after the Sony fully read sensor overheats, or a light drizzle shorts it out, or the battery goes dead? :D

The Sony's are great if you can keep them running.

Michael

D810 is not going to match A7s for video quality, even in 1080P, as A7s does full sensor readout. D810 (like other DSLRs) will skip pixels for video 

I've never seen anything from Sony saying that it does full sensor readout for anything other than 4K.  Where did you see that?  If it does full sensor readout in 1080p, then I am surprised that I saw aliasing on a video shot with the A7S in 1080p.

Michael

After shooting with a d800 every other camera looks a generation behind in comparison.

And the D810 seems an improvement in every way. It may even have a good 1080p video mode. We don't know.

We have to keep in mind that the Sony doesn't record 4K either, unless you strap a huge, bulky $2000 external recorder (Shogun) to it.  It will be interesting to see how the d810 compares at 1080p.  The d810 does have the Expeed 4 processor, which is used in the 7000 series that has pretty decent video, although not at the level of the GH4 obviously.

Michael

I think if anything needed grading, it would be this video.  Maybe they were trying to show what SLog2 looks like right out of the camera.  The aliasing seems to be pretty much under control.  Just saw a bit with the grates.

Michael

Hello Everybody!

 

This is my first post (although I'm an avid follower of EOSHD from day one!) so first of all I'd like to thank Andrew for the amazing job he does for the filmmaking community with his very informative, unbiased and inspiring work!

 

Here's a little short film that i've realised while testing out my new GH4, feedback and comments are obviously much appreciated! :-)

 

 

Ciao!

Nice people watching video.  Seems like the camera stays pretty low profile in these street scenes.  I only saw one person actually look at it.  I guess that's the benefit of its small size.

Michael

This is the camera I want to see also. Perhaps there would be overheating issues because of then large sensor? I'd be content with 10bit 1080 to a Ninja like the GH4. Oh well, it will happen one day ...

The Sony A7 and A7R are known to overheat, sometimes within only 15 minutes (or even less under some circumstances).  I'm wondering if they got that corrected on this model.

Michael

4K when edited in 1080 has so many uses I don't think I could go back.  Here's an example of a video I did last week. Shot and edited in one day. No color correction, to be viewed at the wedding.  There are many shots where I cropped into a 4k image and it gave me a two camera shoot look without doing a darn thing.     The chase around the tree scene for example here.

 

Very nice video!  Well done.

Michael

I would love to hear some audio where someone either didn't boost it so we could hear it better, and also didn't clean it up so we can hear it at all.

How does the noise compare to other cameras (Blackmagic excluded, of course :) ) ?

Michael

In terms of stills image quality, I think sites like guesstheformat.com are pretty telling - people do little better than chance trying to distinguish between M4/3 and Full Frame (when presented with a FF image and given the choice between FF and M4/3, people only correctly identify it 58% of the time - less for APS-C vs. M4/3).

I'm only getting about 50% correct on this site.  It doesn't track Full Frame vs. ...on an individual basis, but I am noticing that the Full Frame images in general pop more, and, of course, have more bokeh for those shots with it.

Michael

I really hope this doesn't mark the end of music videos, both new, and ones being pulled down.  I've always been a fan of them.  Music and video really go together.

Michael

DxOMark has the test scores in for the Sony a7S.  It's the new low light king with a ISO score of 3702, edging out the Nikon Df's score of 3279, and D4 with 2965.  Others, Canon 5D Mk III at 2293, and Nikon D610 at 2925.

When compared to the Canon 5D Mk III, the dynamic range was higher at all levels by about one stop, and more above ISO 6400.

When compared to the less expensive Nikon D610, the a7S again pulled ahead above ISO 1600, but below 800, the Nikon came out on top, with about one stop advantage at 200 and below.

Tonal range were similar for all, until ISO 128,000, where the Sony pulls ahead.

S/N ratio is surprisingly close for all, until 512,000, where again the Sony leads (whose going to shoot there anyway).

Color Sensitivity between the Sony and Nikon are similar, with both slightly edging out the 5D.  The Nikon tops the Sony below 400, and the Sony pulling ahead at 128,000

DxOMark Overall Scores:

Sony a7S=87

Canon 5D Mk III=81

Nikon D610=94

Michael

I'd say its fake. Both shots from GH4 with slightly different grading (hence the difference in highlight/shadow detail).

Exact same framing and DOF?  Suspicious.

Michael

Yes you seem to think sensor size has something to do with stabilization/shakiness of the footage. It doesn't. If you're getting more stable results out of your 5D then that's because it's a heavier, easier to hold camera, thus making it a bit more stable in your hand.

Bigger, heavier (to a point) cameras probably are easier to hold steady handheld.

Michael

What I found interesting to see is that they measured the greatest dynamic range and best Signal to Noise at ISO 100 (measured at ISO 88), you have only access to ISO 100 when you turn on the Extended ISO range, something I never did before now :-)

 

I have just published a blogpost comparing the usable dynamic range of the BMPCC, Nikon D800 and GH4. I also show how I conducted these tests. In my opinion the usable dynamic range is around 7 stops. If I did something wrong in these tests I would really like to know how I could improve it.

I really like your camera test.  Great info there.  I, too, have been wondering about the dynamic range of the cameras tested.  I hope you test some more cameras, even though I know you thought it was boring. :)

This got me thinking.  If you are using an 8-bit Codec, wouldn't the maximum number of stops of dynamic range be 8, perhaps 9 if you throw in gamma?

Michael

Saw this article at Streaming Media, about the HEVC (also known at H.265) licensing terms, and how are likely to keep HEVC from being adopted.  The costs are too high.  That would be a big blow for 4K distribution, since more efficient encoding is needed to make 4K distribution practical.

http://www.streamingmedia.com/Articles/Editorial/Featured-Articles/MPEG-LAs-HEVC-Licensing-Terms-Are-Flawed-Will-Prevent-Adoption-97446.aspx

Michael