July 21, 2014

Does the $2,500 Sony a7S Have Dynamic Range Similar to an ARRI ALEXA?

While the full-frame 1080p/4K a7S from Sony is proving to be an absolute beast in low-light situations, it's far more than just a night-shooting camera. Besides resolving what looks like a very solid 1080p image (an external recorder is required for 4K), it's also got some pretty fantastic dynamic range. How good? Well the folks over at cinema5D took the camera for a spin, and measured it at over 14 stops, right next to the ARRI AMIRA, which uses the same sensor as the even higher-end ALEXA, which is being used on tons of Hollywood and indie features.

If you missed it, here is how good the camera is in low-light (courtesy of Philip Bloom):

And the dynamic range chart from cinema5D:

cinema5D Dynamic Range Test-Scores_DR

And the DSC Labs chart:

Here's what they said about the numbers above:

Here we tested usable dynamic range of the given cameras. With 14.1 stops the usable dynamic range of the A7S comes surprisingly close to the Arri Amira with its legendary Alexa sensor (see our full review here).

This is an extremely good dynamic range rating and is fascinating considering that the A7S is available at a fraction of the Amira’s price and is also in a completely different weight and size class. While the Amira will outperform the A7S in other tests, the dynamic range is a very important attribute to consider when working with a camera.

The Canon cameras come in at 11-12 stops of usable dynamic range. This is still a very strong dynamic range rating, but in comparison to the A7S the Canon’s are way behind.

The Panasonic GH4 had the worst dynamic range in our test. This is in line with the rather videoish look and contrasty colors we can subjectively observe.

Some ungraded S-Log2 footage from ROMAN | LEGION, which is the profile used in the dynamic range test above:

It's also worth noting that some of Sony's press materials mentioned 15.3 stops of dynamic range, here's the Amazon listing:

Presenting the world’s smallest and lightest1 full frame interchangeable lens camera. With a groundbreaking 35mm large pixel image sensor rated at 15.3-stops of dynamic range and an ISO 409,600 sensitivity2, the α7S reveals astonishing detail and color even in the dead of night. Video excels with Full Pixel Readout, a 4K-optimized sensor and uncompressed 4K output. Fast, intelligent autofocus completes the picture.

While another testing site, DxOMark, measured the camera at 13.2 stops, they are only measuring the RAW photo capabilities, so it's possible that Sony is really pushing the sensor in video mode to get the most out of the 8-bits of video that are there. The processing in the camera combined with the S-Log2 looks like a lot of detail that might normally be lost in shadows is being preserved.

No camera is perfect, and for the price to be this low, it can't have absolutely everything. For example, the S-Log2 mode has a base ISO of 3200 (not a typo). So even though you can get incredible dynamic range out of the camera, it's going to require a bit of ND filtration to squeeze every ounce of it -- though it should be mentioned that there are other picture profiles on the camera that also get very good results. Rolling shutter seems to be at the higher end of DSLRs as well, though it's not quite as bad in APS-C mode:

For a $2,500 camera with high frame rates to be producing sharp 1080p and dynamic range close to an ARRI is quite a feat. The Blackmagic Cinema Camera and Pocket Cinema Camera have very high dynamic range as well, though they lack high frame rates and don't have quite the impressive low-light abilities the Sony cam does. Again, no camera in this price range is perfect, and all of them, from the Pocket to the a7S, can produce excellent results when used to the best of their abilities.

Be sure to head on over to cinema5D to read more about their test.

Links:

Your Comment

87 Comments

Interesting- but the devil is in the details- what we really need to know is not the total usable dynamic range, but the over under spread. The fact that the Alexa has 7+ stops of over exposure range, combined with the soft roll off and beautiful color science is what gives it such a great look.

If the A7s only has 5 stops over, like most cameras do, then it will never approach the look of the Alexa, even if it has 14+ stops of total range...

This test is interesting- but more info is needed before any real judgements can be made IMO.

July 21, 2014 at 6:55AM, Edited September 4, 11:56AM

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I've included their A7S DR chart above, looks like it may have more under than over if you check it out on a Waveform. Would definitely be interested seeing more tests done showing the camera compared to the AMIRA or ALEXA in different shooting scenarios, pushing middle grey on all of them over and under.

July 21, 2014 at 7:46AM, Edited September 4, 11:56AM

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Joe Marine
Camera Department

Thanks- I'm out traveling for a shoot and evaluating this stuff on my phone is not the way to go- which is why it would be great to actually have numbers published / shown. My gut says this probably still has about 5+ stops over- which in the end doesn't impress me, as that means I have to light more to help protect the highlights- when compared to the Alexa.

It would be great to be wrong on this. If the sensor does have 7 stops over, that would be HUGE...

July 21, 2014 at 9:02AM, Edited September 4, 11:56AM

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Thanks for making this point. This is one of the things that mystified me about the RED Dragon sensor - all the touted extra dynamic range was in the shadows. The highlights still looked crappy with an unnatural rolloff.

As far as affordable cameras, the BM ones seem to have the most Alexa-like highlight response when the raw footage is treated correctly. It's not perfect but the amount of extra highlight information in a BMPCC raw frame that is processed to linear exr is admirable for a $500 camera. It may have noisy shadows but I care more about the highlights.

July 21, 2014 at 1:38PM, Edited September 4, 11:56AM

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Michael

That was the old OLPF, although it did increase the highlights by 1 stop over MX. The current incarnation of Dragon (new OLPF), as tested and confirmed by Ryan E. Walters, has 7+ stops of dynamic range above middle gray. There are maybe one or two other sensors that can make that claim. This means it had the extra stop to give when they changed OLPFs. Not too shabby for a 6K sensor.

July 21, 2014 at 3:26PM, Edited September 4, 11:56AM

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Brian

Yeah, the new OLPF does look a lot better in the highlights with the Dragon for sure. Now that camera is having the opposite problem- it is noisy in the shadows. For some that is a deal breaker, but for me, I want more room in the highlights so that I can get a more filmic looking image. :)

July 21, 2014 at 7:52PM, Edited September 4, 11:56AM

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I agree. Noise can be dealt with in a number of ways. And if it looks good, I don't mind a little texture in the image. For my money, 7 or more stops in the highlights is where the action is. It's where the refinement in an image is most noticeable. Deep shadow detail is cool to have but it's usually not what's most intriguing in the frame. It seems the recent trend is wanting to practically see in the dark and the A7S is going to produce some novel and compelling imagery on that front. However, film kicked video's arse a long time ago when it comes to narrative storytelling for a number of reasons, not the least of which is film's beautiful highlight performance.

July 21, 2014 at 8:40PM, Edited September 4, 11:56AM

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Brian

Where I can learn more about over-under spread?

July 21, 2014 at 4:49PM, Edited September 4, 11:56AM

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+1

July 21, 2014 at 7:24PM, Edited September 4, 11:56AM

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nate

I cover that in this post / test I did here: http://indiecinemaacademy.com/red-epic-dragon-vs-red-epic-mx-hype-real-p...

And if you want to see a whole bunch of cameras profiled against each other, I have the profiles you can download and load into teh Sekonic DTS software here: http://www.ryanewalters.com/SP/sekonicprofiles.html

Hope that helps. :)

July 21, 2014 at 7:49PM, Edited September 4, 11:56AM

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BTW- If someone does have access and the time- here is how the over / under evaluation can be made using the published charts: (I can't get to this until at least the end of the week.)

1. Download the charts (Ideally, in their native format, but whatever you can get your hands on.)
2. Bring it into FCP-X / Resolve / Premiere (Something with a waveform)
3. Count the stops over and under middle grey for each chart / camera. (That is each line in the chart)
3a. For Sony cameras shooting in S-Log 2, middle grey = 32% IRE
3b. For Canon cameras shooting in C-Log, middle grey = 32% IRE
3c. For Arri Alexa shooting in Log-C, middle grey = 38% IRE

July 21, 2014 at 8:17PM, Edited September 4, 11:56AM

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July 21, 2014 at 9:09PM, Edited September 4, 11:56AM

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nate

Yep- exactly- you rock! Thanks. :) Based off of that chart (which was processed using the web version / JPG- I am assuming) it looks like if you rate the camera at ISO 3200, and expose mid-tone at 32 IRE, then there is about 6-ish stops of over exposure range. (The first / top chip doesn't count because that is clipped.) So that is GREAT to see.

But it also looks like (based off of the chart) that if you rate it that way, you only get about 5-ish stops of under exposure range. Which, for me is fine. But for people who want to see into the shadows more, might be an issue...

July 22, 2014 at 5:41PM, Edited September 4, 11:56AM

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Worth mentioning that Sony claim 15.5 stops for the F5 and F55 in SLOG3.

July 21, 2014 at 10:13PM, Edited September 4, 11:56AM

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@Simon. Have you bee able to test this?

July 22, 2014 at 9:49AM, Edited September 4, 11:56AM

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Rich

As far as I know, the sensors in the F55/65 are rated at 14 stops by Sony. Even if Slog3 allows 15.5 stops I don't see the benefit if the sensor can't capture that.

July 22, 2014 at 12:45PM, Edited September 4, 11:56AM

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Rich

I havent tested it. I'm not a fan of slog3 because it puts more detail in the shadows at the cost of highlights where as slog2 which I love on the F5 has really great highlight detail and rolloff.

To me the eye is drawn to highlights not shadow, so it makes sense to use slog2 over slog3. I just prefer the look of slog2.

July 22, 2014 at 9:15PM, Edited September 4, 11:56AM

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Why not put the 13stops of the Blackmagic Cinema Camera in this comparaison.

July 21, 2014 at 6:59AM, Edited September 4, 11:56AM

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Mapas

there is no proof of that 13 stop DR except marketing material by Blackmagic

July 21, 2014 at 8:37AM, Edited September 4, 11:56AM

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Art

There have been countless tests run on the BMCC and it's dynamic range. This is one that was profiled on this very site and concluded 12 1/3 stops DR. I have seen tests that suggested more and some that suggested less.
http://nofilmschool.com/2013/03/blackmagic-cinema-camera-red-epic-arri-a...

July 21, 2014 at 9:02AM, Edited September 4, 11:56AM

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Weldon

July 21, 2014 at 6:09PM, Edited September 4, 11:56AM

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Abe Froman

Take that site with a huuuge grain of salt. Those measurements don't make any sense, 5dmarkIII will have the DR in raw video as in raw stills and that's 11.7 according to DXOMark. The only way to think the BMPCC has the same dynamic range for all the modes has to be a measuring error because there is only one ISO on the BMPCC.

July 22, 2014 at 11:57AM, Edited September 4, 11:56AM

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Terppa Teuvonen

Usable DR is always subjective. I decided that I would stop counting when I could no longer see fine detail in the shadows. You can see where the numbers come from in this video:
https://vimeo.com/81034088

If you go there you'll see I'm looking at very fine detail in a very dark shadow, so it's normal that my numbers are lower than those from dxomark. It's the same test for all cameras, though, so the table makes perfect sense.

July 22, 2014 at 6:36PM, Edited September 4, 11:56AM

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I wish they would show some of the work that led to these conclusions. What ISO? what picture profile settings? What is their threshold for acceptable noise. I've read tests peformed with the same DR chart that came up with different results for the GH4 and the process was shown in detail. Tests are only as good as the impartial process.

The A7s looks like a great camera although it doesn't meet my needs & is more specialty cam to me but I will still probably buy one for all it's strengths.

July 21, 2014 at 7:34AM, Edited September 4, 11:56AM

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AdRath

I find it hard to believe that 5D3 h.264 beats C300 Clog for DR, Having used both (more c300 than 5D) The C300 Clog is much better than the 5D3 h.264 in terms of DR.

July 21, 2014 at 9:15AM, Edited September 4, 11:56AM

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AdRath

Same here. I used the C300 in many occasions including 2 mainly outdoors project in harsh light in Congo and South Africa and I was always impressed by the latitude I got out of the Clog. It felt almost as good as my FS700 Slog2 with Odyssey 7Q and that combo is rated at 13.5 stops.

July 21, 2014 at 10:12AM, Edited September 4, 11:56AM

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If you click through to their article, there is a bit more explanation to this. They said something to the effect that the overall softer image of the 5D3 led to more usable DR because noisy shadow areas were more smudged. So perceived DR was higher.

July 21, 2014 at 10:44AM, Edited September 4, 11:56AM

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BTW- I'm on a shoot right now where we are using the 5D MKIII and C100 (Same chip as the C300) and it is easy to see that the C100 has at least 2 stops more highlight latitude then the 5D does. I'm able to retain a lot more detail out the windows in the background with the C100. That is clear and easy to see for everyone on set. (Which is why we have to frame more carefully with the 5D.)

However, if the extra DR in the 5D is in the shadows due to the "blurring" of the noise due to the H.264, then that is a more subjective rating, as we all have different tolerance levels for noise. And it seems if that is going to be the case for how it is judged, then shouldn't all the footage be converted down to H.264 for a more "neutral" / "fair" - ish, evaluation?

July 21, 2014 at 8:04PM, Edited September 4, 11:56AM

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If you follow the link to the site that did the work, they do explain it. They used native iso's and list the picture profile. They also explain why the 5d3 beats the C300 in usable DR.

July 21, 2014 at 10:43AM, Edited September 4, 11:56AM

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Brett

what we need is a comparison in images. especially for the highlight rolloff.

July 21, 2014 at 9:12AM, Edited September 4, 11:56AM

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Premini

This was posted yesterday ...not exactly a DR test but, least, it's A7s in 4K (vs. GH4).
[ https://www.youtube.com/watch?v=HUHVT9GZRa0 ]
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The white balance is off on the A7s footage but the uploader promises more clips down the road.

July 21, 2014 at 10:02AM, Edited September 4, 11:56AM

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DLD

That was the worst porno I've ever seen.

July 21, 2014 at 11:25AM, Edited September 4, 11:56AM

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von

Seconded

July 22, 2014 at 6:17AM, Edited September 4, 11:56AM

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Nick Hiltgen

Someone needs to tell her that there are candles on the floor.

July 28, 2014 at 4:33AM, Edited September 4, 11:56AM

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Truth

Thanks NFS, this was really useful :)

I want to get something small and compact to shoot personal bits with so I nearly spent money on a GH4 but then luckily got to shoot with one for a day the other week. While on paper (and practicality) the specs are great for the money, I personally found the colour science sucked. Skin tones were pretty ugly and I found it pretty tough to push variation back into the skin (specular highlights didn't seem to be respected properly by the log profile) which sadly made it an immediate write-off for my tastes which is a real shame. For budget camera image quality, I still have a big place in my heart for the 2.5K BMCC but I'd be over the moon if this allowed me to have some higher frame rate options without losing the DR and gorgeous colour from the Blackmagic.

July 21, 2014 at 10:34AM, Edited September 4, 11:56AM

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I love Speedoosters! ;)

July 21, 2014 at 11:21AM, Edited September 4, 11:56AM

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Will

It still looks like shitty 8 bit video. I like the image better than the GH4, but still doesn't look very filmic.

July 21, 2014 at 11:24AM, Edited September 4, 11:56AM

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von

There are enough "film convert" type packages around if you really want that look. Impulz has just released an update that our buddy Luke Neumann played around with -
[ https://www.youtube.com/watch?v=PFw3X5yy1Gw ]
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I would like to see how these LUT options work with the GH4 and A7s footage too.

July 21, 2014 at 1:43PM, Edited September 4, 11:56AM

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DLD

Funny because in the documentation for Osiris LUTs, vision color mentions:

"Don't shoot LOG when your camera outputs crappy 8-bit compressed files (DSLRs). Just don't. Granted, the before and after color grading comparisons will be more impressive when you start with LOG footage but that's like saying good Make-Up artists should
only work in the old folks home to show off their skills. No offense. ;)"

July 23, 2014 at 9:26AM, Edited September 4, 11:56AM

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Buzz

Filmic is going out, it's passé.

July 22, 2014 at 9:07AM, Edited September 4, 11:56AM

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ivan noel

For $2500, this is an amazing camera. Digital cameras have grown tremendously in the last 10 years and we are spoiled beyond belief, to the point where we would make pithy comments about it looking like sh*t or mocking it for not looking "filmic." Great movies have been made with cameras with far worse specs than this Sony or the GH4, for that matter.

Why can't we just say, "Thank you Sony and Panasonic for continuing to improve the quality of your cameras and selling them to us at a great price." Sorry. Rant over.

July 21, 2014 at 1:26PM, Edited September 4, 11:56AM

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Sean K

Seriously! Imagine if something like 28 Days Later could have been shot on the A7s or similar instead of the Canon XL1.

July 21, 2014 at 3:00PM, Edited September 4, 11:56AM

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alex

Great camera A7s sans the rolling shutter and this is not even in 4k mode yet so who knows what that will be when recorder is released

This test seems questionable because it is the first time hearing that 5d was better than Gh4 , especially seeing how many say the compressed 4k codec has better dynamic range than 5d raw

July 21, 2014 at 4:50PM, Edited September 4, 11:56AM

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cjay

I don't think you can really go too far wrong with this cam as a purchase, value proposition through the roof. A7s vs alexa is an unfair comparison at every level, and who really cares anyway? I'd be far more interested in how quickly in let's me shoot on set. All dslr's slow you right down, the alexa let's you shoot insanely quickly. That's all I need

July 21, 2014 at 2:47PM, Edited September 4, 11:56AM

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I care, love the Alexa look but can't afford the 80K.
Also want to do ariel stuff so looking for a small camera for that too. Can't afford a helicopter to carry the Alexa.
Been waiting for a camera with good rolloff in the highlights for ages

July 21, 2014 at 4:34PM, Edited September 4, 11:56AM

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Ade A

I worry that the rolling shutter will make this a tough sell for drone work. Unless you go the "crop mode" route. I find that aerials don't need TOO much DR and you can always throw on a gradual ND to get a great image from the GH4...

July 21, 2014 at 6:31PM, Edited September 4, 11:56AM

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Luke, why did you decide to delete your fb page? It's how I kept up with your work.

July 23, 2014 at 10:13AM, Edited September 4, 11:56AM

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alguti

Keep on waiting... I doubt that the A7s rolls off the same as the Alexa... If I'm wrong and the A7s does have teh same 7+ stop soft roll off that the Alexa has that would be great!

July 21, 2014 at 7:56PM, Edited September 4, 11:56AM

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There's no roll-off with S-LOG, even for F55/F65, SONY sensors strength is shadow DR.

I believe S-LOG2 on A7S uses ISO400 for base exposure, then it does a digital push in the shadow area to ISO3200. Reason why the shadow is so noisy.

July 21, 2014 at 10:59PM, Edited September 4, 11:56AM

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Ash

That would make a lot of sense why the camera looks so noisy...

I've also noticed that Sony cameras in general have a stronger "blue" bias to them. They have always felt colder in comparison to Canon cameras. Not that it is necessarily a bad thing- it's just a part of the Sony look. Just like Canon, Red, Panasonic, etc. all have their own look.

July 22, 2014 at 5:45PM, Edited September 4, 11:56AM

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For me this is the video that sold me on the A7s. https://vimeo.com/100397024 Look at the Dynamic Range between the shadows & highlights. Its insane!

July 21, 2014 at 3:09PM, Edited September 4, 11:56AM

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I'm glad it what impressed you in that video was the DR between the shadows and the highlights because it certainly couldn't have been the red bias. Sunburned looking skin abounds. Anything colored red or reddish orange pops. If this footage is typical of the A7S Then it seems to have the same problem that plagues the Digital Bolex D16.

The footage also contains what seems to go hand in hand with red bias- the blues take on an unnatural candy color shading close to azure blue.

July 21, 2014 at 5:54PM, Edited September 4, 11:56AM

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Garrison66

That teal look in the shadows...

ughhhh

July 21, 2014 at 11:55PM, Edited September 4, 11:56AM

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alex mand

Are you serious? Download the 2GB file and look at the oranges at the end - macro-blocking everywhere. This is what happens when you push an 8-bit too far.

July 22, 2014 at 5:44AM, Edited September 4, 11:56AM

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Johnny

Someone please find out what ASA this camera is rated for best performance-- no one seems to have this information, not even Sony.

And for the love of bananas, please stop showing clips from Philip Bloom. He doesn't know what he's talking about.

July 21, 2014 at 4:06PM, Edited September 4, 11:56AM

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a7saf

I believe the answer is 3200.
Thats the minimum PP 7 S- Log sets it to as well.

July 21, 2014 at 4:32PM, Edited September 4, 11:56AM

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Ade A

"And for the love of bananas, please stop showing clips from Philip Bloom. He doesn’t know what he’s talking about."

For someone who "doesn't know what he's talking about," he sure is impressing all the right people. Unless a7saf is code for Steven Spielberg, I don't think you have room to talk. Keep your negativity to yourself.

July 21, 2014 at 5:12PM, Edited September 4, 11:56AM

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Sean K

I am sure a7saf was making a joke about Mr. Bloom. Every one I know loves Philip and appreciates his work and talent. I am sure this did not come from a negative place. ; )

July 22, 2014 at 12:36AM, Edited September 4, 11:56AM

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Tyler

Personally I really like Philip Bloom 's reviews, with him taking the time to use the cameras to a get sense how easy or difficult they are to manage. Knowing a cameras limitations helps in planning work flow with that camera. Love those bananas.

July 21, 2014 at 6:54PM, Edited September 4, 11:56AM

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Hari Har

I would agree with most of the other's. Please if you can't say something kind, keep it to yourself.
If you were paying Mr. Bloom for his views & reviews, then bash him privately.

I can't imagine the money and time he spends sharing his personal evaluations of equipment. I could not begin to do it. He shares freely. Give him a bit of 'thanks' or just don't view his work.

I enjoy the various professionals who help me with choosing my camera's. They offer their time and insights for -- free. Then I spend thousands of $$, with the hopes of meeting my limited but demanding skills in tough environments. I have a BM, Nikon, and now want to upgrade my Nikon for run and gun work.

I applaud each & all of their efforts to help the video enthusiast's of the world.

July 21, 2014 at 9:33PM, Edited September 4, 11:56AM

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My god Sony has a monster sensor in this camera.

Wow.

July 21, 2014 at 8:39PM, Edited September 4, 11:56AM

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Theo Slawin

cramming 14.1 stops of DR in 8bit codec results in less the 17 code value per stop, this will cause many issues with critical areas like skintone and image banding.

July 21, 2014 at 10:50PM, Edited September 4, 11:56AM

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Ash

July 22, 2014 at 12:21AM, Edited September 4, 11:56AM

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Theo Slawin

Not wrong

8bit with 14 stops DR graded looks ok on a computer display <24inch with Vimeo/Youtube compression.

but if you view all these footage un-compressed on a 10bit 4K 84inch screen, the difference is apparent.

not to mention a cinema screen.

July 22, 2014 at 5:28AM, Edited September 4, 11:56AM

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Ash

Gene is right and your wrong.

I one the a7 and a x900b. No banding.

July 22, 2014 at 2:12PM, Edited September 4, 11:56AM

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David White

Theo, nice tests. I still think the 5d3 yielded the best image in terms of color depth. One problem I've had with Slog in general, especially F55/5is the inaccurate colors. When I'd time the flesh tone right (initially heavy on magenta) my Macbeth chart would be completely off. In other words, a professional level grade requires a lot of windowing around faces. Too time consuming. In fact, we did extensive tests on the last feature I shot, comparing Alexa, Dragon and F55. The Alexa by far yielded the best image in terms of skin tone and highlight roll off. Dragon came in 2nd. While an impressive DR, it had color aberrations in the clipped area and not as much depth in skin tone. The F55 was dead to me. Again, decent DR, thin and inaccurate colors.

While you draw some definitive conclusions based on these tests, I'd test again but this time with faces and a color chart. You'll be surprised. It's one of the reasons I find the GH4 a complete loser as its flesh tones look like plastic to me. The 5d3 / raw really shines with people.

July 22, 2014 at 2:20PM, Edited September 4, 11:56AM

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What if you use an external recorder, for example the Atomos Ninja Star or Shogun?

July 22, 2014 at 11:44AM, Edited September 4, 11:56AM

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MP

Well, this settles it for me. I was torn between purchasing the A7s and purchasing the Alexa, but the numbers are pretty clear.

July 22, 2014 at 12:06AM, Edited September 4, 11:56AM

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Garry Shandling used to have this bit in his routine years ago, ~ "So, I walk over to a newsstand, ask the sales clerk if he has the "Nation" in stock and he says, "Sorry, all out". Then I ask, "What about Newsweek?". All out too. The "US News and World Report? Been sold out for days. So, I say, "All right. Just give me a copy of "Hustler"".

July 22, 2014 at 3:50AM, Edited September 4, 11:56AM

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DLD

Shoot faces with both cameras and I'm sure you'd draw a different conclusion. From what I've seen like all S log (f55/5), the A7s has a definite bias towards magenta as well as from everything I've seen, somewhat thin color depth, especially on skin. I've done extensive testing with the f55 and drew a similar conclusion. A/B'd against the Alexa, the F55 is dead in the water. DR is but one metric to measure a camera by. The most important being it's ability to render skin tone. There's a reason Arri dominates both features and TV, and it's not resolution.

July 22, 2014 at 2:36PM, Edited September 4, 11:56AM

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July 24, 2014 at 7:31AM, Edited September 4, 11:56AM

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dusty

Also, the BMC 2.5k and BMPCC both have better DR than the BMC 4k. But the 4k produces a clearly better image, especially on faces.

July 22, 2014 at 2:39PM, Edited September 4, 11:56AM

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If this camera allowed 10 bit external recording it would cause a chaos in the indie game killing sales for black magic, red, arri , Panasonic and even Sony's higher cinema cameras making atomos and possibly other 3rd party recorders rich in the process .

This camera is amazing , only thing questionable is the jello effect possibly in crop mode also and 8bit codec , I'm sorry but 8bit is still 8bit , trust Sony is well capable of producing a 4k internal camera especially one capable of 8 bit externally

July 22, 2014 at 12:43AM, Edited September 4, 11:56AM

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cjay

I agree the camera is amazing but it's the jellocam prob that scares me - it hasn't looked favorable so far. I was really rooting for this camera but I can't have jello issues on handheld shots.

The camera that has completely caught me by surprise is the Nikon D810 - it just has a quality/feel about it that reminds me of the Alexa or 35mm it's definitely top of my list... for now.

July 22, 2014 at 1:21AM, Edited September 4, 11:56AM

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Lance Bachelder

I didn't read all the comments in case this was mentioned, but in pre-digital times low-budget stuff was usually shot on reversal, which had 8-9.5 stops (and zero latitude of course). Shooting negative with 12-13.5 stops was nice, but then not being able to afford the lab costs of a full answer print process - or even a good quality telecine session - made that latitude underutilized (photochemically you could only really use 8-10 stops of that 12-13.5 stop range on the neg). Plus we now have WYSIWYG monitors with histograms/zebra/etc so latitude isn't quite as valuable.

Just mentioning this stuff to keep things in perspective… even 10 stops of dynamic range with no lab costs (not to mention highly resellable gear instead of spending most of our budgets on film stock) is pretty great.

July 22, 2014 at 2:05AM, Edited September 4, 11:56AM

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Remember when we used to have wooden horse-drawn carts? Now we have cars made of aluminum and rubber wheels! Who needs automatic transmission, shock-absorbers, power-steering, or anti-lock brakes? We should just be grateful that the car runs on an engine.

July 22, 2014 at 10:42AM, Edited September 4, 11:56AM

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BW89

Jean is perfectly correct in pointing out that so much has been done with so little when it comes to great cinema - but not wooden carts though.

July 22, 2014 at 2:11PM, Edited September 4, 11:56AM

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William

That was a very ignorant comment BW89.

July 22, 2014 at 6:27PM, Edited September 4, 11:56AM

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Larry

If a filmmaker needs 14 stops of dynamic range because they can't get it to work with 11, then there's something very wrong going on. Also, nice metaphor about the wooden cart versus automobiles… though what you were meant to infer from my comment thingee was that people should be in their cars driving around at a nice 50 mph instead of fixating on worrying that their Toyota isn't as great as the new 2015 Land Rover.

July 22, 2014 at 11:57PM, Edited September 4, 11:56AM

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Well, if it's 11 stops with smooth rolloff like photochemical film emulsion then yes, duh. In digital world you absolutely need to have more room to effectively have the same kind of image you'd get straight on film.

July 25, 2014 at 7:28PM, Edited September 4, 11:56AM

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Natt

You are correct, but a photochemical film print (positive) only contains 8-10 stops of dynamic range derived from within the 12-13.5 stops on the negative, with the standard print being 9 stops. So with 11 stops, that leaves you decent shoulder & toe to s-curve for rolloff (likely 0.5 for shadows and 1.5 for highlights).

July 28, 2014 at 10:22AM, Edited September 4, 11:56AM

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From Cinema 5D:

"RAW:
A7S = 10.51 EV
GH4 =12.76 EV"

After a poster asked where the 3.6 extra stops came from in A7S video:

"The slog 2 at 3200 iso gets its dynamic range by exposing at a lower gain then digitally pushing the mid tones. It might be 200 iso pushed up"

From what I have seen so far of the real world test imagery coming off the A7S, it is not likely to compete with Alexa. But I'd be as happy as the next guy if it did.
On that note, considering these DR claims, the differences between the A7S and the GH4 in these real world scenarios, harsh light and so on, should have been significant, they were not. Far from it. Next. Perhaps Mr. Walters will take a peek and explain what is really going on here.

July 22, 2014 at 3:29PM, Edited September 4, 11:56AM

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William

Unfortunately I haven't had the time to review all of the test procedures from the DXO test, and then see how Cinema5D did their tests in order to compare what is going on.

As far as the test footage goes- I haven't see a good side by side test with the GH4 and the A7s yet. The videos that I have seen seem to have at least one parameter off- white balance, not exposed correctly, light changes, poorly graded, etc. So they haven't been useful to me in terms of making a properly informed evaluation. I hope to get my hands on a camera soon...

July 22, 2014 at 5:59PM, Edited September 4, 11:56AM

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July 23, 2014 at 6:48PM, Edited September 4, 11:56AM

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Bavarian Filmmaker

Has anyone seen the APS-C crop mode in 4K? In theory wouldn't this just be upscaled from 1080? Also, anyone know the crop for 720p 120fps?

I've heard rumors that the 1080 APS-C crop is slightly cleaner than 1080 full frame. Anyone?

July 25, 2014 at 12:31AM, Edited September 4, 11:56AM

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scottr

a7s is 2500 dollars. Alexa is 80000 dollars. So you can buy 32 of those with price of a Alexa.

August 1, 2014 at 5:53PM, Edited September 4, 11:56AM

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ruknus

I found BMPCC footage has more DR than A7s.

August 8, 2014 at 4:38AM, Edited September 4, 11:56AM

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Fadhil

As a Nikon shooter coming from photography and learning videography, are there any decent cameras worth comparing with these cameras above for good quality and dynamic range? say like D810 or even the new D500?

September 18, 2016 at 3:30AM

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Prajwol Bhattarai
Photographer/Cinematrographer
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