PXW- FS5 - A very "soft" 4k image?

[Mark Watson]

Cliff,

Sounds like you're one of Ken Rockwell's "Measurators". I suffer from that also. I find that there are a lot of well-intentioned, yet miss-informed people in this field, so I tend to try to find out for myself about some stuff, but not at the level you're going into. I try to follow along with some of David Heath's tech talk, but most of that is way over my head, and googling sensor specs doesn't help me much, even with the diagrams. I'm with Noa on this one.

Mark

[Cliff Totten]

I placed a question mark in the title not to make a factual statement but to make it more of a debatable "question".

"Soft" is very relative. Does it resolve more detail than any HD camera? Hell yes. Does it resolve more detail than other Sony UHD cameras that take in WAY more pixels and down sample? In my opinion, no. Should you care? There is no right or wrong answer, that's totally up to you.

This topic is also NOT about the "art" of film making. Can you make a spectacular film with the FS5? OF COURSE YOU CAN! This topic is about the "science" of image sensors and specifically about resolving power. It is intended for people that care about this "geeky", "pixel peeper" subject.

I'll upload some samples on Saturday. I want to show the difference in grass and foliage and fine textures in bright daylight. I cant do that until Saturday because when I get home on the week days its dark out.

Look,....this is a subject that I personally care about. But other's might not, and that's OK! The subject of Bayer pattern removal, Nyquist frequency, aliasing, sampling and low pass filters IS NOT FOR EVERYBODY. It's tedious and terribly NERDY! If you don't dig it and find it boring.....that's TOTALLY cool!

Again, transmission engineeres, piston designers and aerodynamics technicians don't necessarily make great race car drivers. AND VICE VERSA!

Again, this is a SCIENCE topic, not a artistic FILM MAKING topic.

CT

[Cliff Totten]

So I did a very quick and dirty test on Saturday between my FS5 and Z150. I think the results are pretty interesting. It appears I'm right about the FS5 image being "soft" but wrong about it having less resolution that the Z150.

At first look, the Z150's image has allot of "pop" and is very sharp. The FS5's tone is clearly smoother and renders shadows much better but it doesn't "appear" to resolve the same detail on a quick glance.

However!....when post sharpening is applied to the FS5's image, it appears to have about the about same "effective" resolution as the Z150. Notice the dog treat bag and the lettering on it. Notice the blades of grass on the second set.

VERY INTERESTING!

I really wish Sony would enable all the DETAIL settings on the FS5. (as some might know, they are all disabled today in the FS5 version 2.0 software) In some cases, I'd rather do this in camera instead of doing it in post.

What do you guys think?

https://drive.google.com/folderview?...VE&usp=sharing

[Ray Lee]

I am no a technical guy like some people here, my take is the FSF allows for a lower sharpness setting than the previous cameras allowed (FS100, FS700, Ea50...) strange at first to turn it all the way down like I always of and find it looked rather "soft"

Thanks for the heads up on the latest firmware changing the sharpness options, haven't had any time and do not think I would have bothered to check that.


Not sure sure what you are saying about the sharpness being disabled in the FW 2.0, setting options look to be the same as the before to me. I also like a bit of sharpening set in camera.

[Cliff Totten]

In this comparison, both the Z150 and the FS5 were placed in their detail "neutral" positions. DETAIL set at 0 and all MAUNAL SET parameters off.

IMPORTANT - There is no sharpness added and no sharpness removed. They are both NEUTRAL.

On the Z150 (as well any other Sony camera) you can go into the DETAIL and MANUAL SET options and swing all the settings wildly and create extreme over sharpening results. However, the FS5's MANUAL SET options dont work. You can grab any parameter you want and move them any which way (even to crazy extremes) and they are literally disabled form the picture control.

This seems to be an FS5 software bug. Maybe Sony is aware of this, maybe they are not?

I'd love for more FS5 owners to try it out and post here.

CT

[David Heath]

Originally Posted by Cliff Totten

It is generally understood that higher resolution sensors will produce higher resolution images. No?

A 16 million pixel Bayer image consisting of 8 million green, 4 million blue and 4 million red pixels will have more resolution than an 8 million pixel Bayer image consisting of 4 million green, 2 million red and 2 million blue pixels. (8:4:4 vs. 4:2:2 RGB million samples)

To your first sentence, then no - it's not necessarily true.

It will depend on a lot of factors, and obviously a big one is how the sensor gets read!

You're no doubt talking about "conventional" deBayering, (where the output image has the same dimensions as the sensor) but that need not be the case. Obvious example is early DSLR video with quite crude pixel skipping, but whilst (hopefully) that is in the past a big step forward came with the techniques as used in the AF100, which basically took a 4x4 block to form a single output pixel. It started off with a 16 million pixel chip - but output a 1 million pixel res image (albeit R,G,B) - so close to 720p resolution. (It actually did a 16:9 crop of the 16 megapixel sensor, so in reality was 12 million down to 0.75 million output, but you get the idea. That corresponded to the measured resolution of about 650lpph.)

Next step up may have been processing as the C300 used. Here using 2x2 blocks to form each output pixel - so a 8 megapixel sensor giving 2 megapixel output resolution.

OK, you may argue that all that was in the past, and now the whole sensor gets read, properly deBayered, and downconverted to the desired eventual resolution. But there's downconversion and downconversion....... It's dangerous to generalise but unless it's done really well, the high resolution off the chip can be more of a hindrance than a help - lead to aliasing rather than truly better resolution. Not necessarily.... but a sweeping statement such as "It is generally understood that higher resolution sensors will produce higher resolution images. No?" just is not necessarily true.

Practically, the FS5 sensor dimensions are the same as most of the "real" 4K cameras on the market today, going way up in price - the F5, F55, Varicam etc. Let's keep that firmly in mind. There's a lot to be said for the OPTIMUM number (and hence size) of photosites on a chip - more certainly does not necessarily mean better.

From the last post, then a "detail neutral" setting may not mean no sharpness added or removed - it may rather be the position that the manufacturer considers "best" - which may not be the same thing! :-)

What you describe (regarding the FS5's MANUAL SET options dont work) seems too fundamental to be a bug. I'm left wondering if another setting is inhibiting their operation in your particular case? Just a thought.........

[Cliff Totten]

Yes, higher density sensors produce more photosite voltage readings than lower density sensors. Certainly, if a company reads only 1 out of every 3 or 5 lines off those sensors, they are only using a partial surface area and the image resolution goes down hill very fast. You are right, a company can waste a high density sensor on how they read it out. You are right about artifacts too. RGGB Bayer pattern by it's very nature will generate aliasing and moire and any image scaling up or down will also add to the problem. All digital sampling of any wave type, no mater what frequency or bit depth will have it's mathematical limits. Binning and summing those values just compounds everything. No argument there.

On DeBayering: I talked to Mitch Gross from Convergent Design at NAB 2016 and I specifically asked him about DebBayering Sony's raw sensor protocol. (As we know, "true" raw sensor is nothing more than individual pixel voltage reading, its position address on the sensor and the RGGB optical color filter metadata flag it sits under...remember all photosites are actually just grey scale) Mitch told me there are many ways to DeBayer an image and some vary significantly. I asked him if Sony has a "recommended" way and do they use it. He grinned at me and said "Well, not necessarily,...sometimes there are better ways" Mitch also told me that no manufacturer "really" gives out true raw sensor data. It's always processed to an approved final output and then sent out of the camera. He did NOT say this next part, but I suspect he was "hinting" that Sony can "dumb down" it's raw data output on it's FS5 if they don't want it to compete with it's FS7 raw data. Again,...he did NOT actually say that and it's just me interpreting the "wink" that I got from him. Still, I thought that was pretty cool. Sony just doesn't give you "untouched" data from their beautiful sensors, they add "conditions" to keep a tight control on things. You get only what they are willing to allow for that model even though it's supposed to be "raw". ;-)

For those that might not know, if your camera says "24 megapixel" image sensor. It does NOT produce 24 million full color pixels. It's only based on 12 million green and only 6 million red and 6 million blue. No single Bayer sensor ever produces the full color pixel density that it's box says it does. It just writes image files that match those frame sizes. The true, full color pixel density is much less. ;-)

I agree with David that more pixels does not necessarily mean a better image. Image quality is not just one factor. The FS5's ability to handle highlights and reach into the shadows is fantastic in my opinion. I think that FS700, FS5, FS7, FS5 sensor was designed for that task specifically.

On "DETAIL" being "neutral on both cameras. I only meant to say they are "factory neutral". However, Sony programmed them in that setting is their thing.

On the FS5's unresponsiveness to DETAIL and MANUAL SET options: These same options existed on my AS7, A7S-II, RX10, RX10-II, X70 and Z150 and nothing was stopping these cameras from allowing you coursen the crap out their image. (not that I ever want to do that) I just find the FS5 to be particularly "flat" compared to every other Sony UHD camera I own.

So why is the FS5 not responding to DETAIL or MANUAL SET?

Doug Jenson has already somewhat confirmed this, can any other FS5 owner try it out?

David, have you seen the FS5 vs.Z150 samples in the post above?

CT

[Doug Jensen]

Just for the record, I only confirmed that the Detail settings do not make a very big difference. But they do make a difference. As I point out in chapter 12 of my FS5 training video, with the right combination of Detail sub-menu settings the sharpness can be increased to a point that I find perfectly acceptable . . . but the change is very subtle.

[Cliff Totten]

Hi Doug,

On your FS5, do any of the "MANUAL SET" options have even the slightest detectable image affect? There are many parameters there that do nothing today. My FS5 does not register anything. Not even on scopes.

Yes, on my FS5 too, the DETAIL settings at +7 have a very, very, very slight effect. I can only see the change on scopes but are not really visible on a 4k monitor.

Again, this is unlike all other Sony cameras I have used where these same settings are capable of easily causing extreme sharpening affects.

CT

[Doug Jensen]

Cliff,
I've been on the road for almost two months and I don't have my FS5 with me -- so not only is it not running the latest firmware I can't pull out the camera and examine the settings again even if I wanted to. I'm going off my observations and notes that I made a few months ago when I spent 8 weeks under the hood of the camera producing my FS5 training video series. At that time, I could detect visible changes to the picture when the details settings were adjusted. They do function -- but we are in total agreement that the changes are very very slight. Also, this is not the first Sony camera to have this issue. I can't remember which camera it was, but a few years ago I was producing a training video or doing beta testing for another camera and it had the same issue where changes to Detail could barely be seen. I can't remember which camera it was, but the FS5 is not the first. I contacted Sony about it and they said that was the way it was, so I didn't even bother to bring this issue up to them on the FS5. It is what it is. And I don't think it is something that will be "fixed" because I don't think it is something anyone at Sony thinks is broken.

[Cliff Totten]

Wow. I do find that fascinating.

For me, of all the Sony cameras I have owned, I haven't had a model that had a problem like this. On Sony cameras that I have purchased in just the last two years, A7s-II, (v1 &2) RX10-II, (v1&2), X70 and Z150, all which have a similar sharpening set, you can use those same parameters to go CRAZY on an image. They certainly work very strongly, we can all believe that.

On my FS5, DETAIL controls are barely visable and "MANUAL SET" otptions are completely dysfunctional. I dont use DETAIL or MANUAL SET on any other Sony camera that I have ever owned. Those cameras are all plenty detailed and sharp and just don't need it. The FS5 is the only Sony UHD camera that I have ever owned that I actually feel NEEDS in camera sharpening. And, ironically, it's the only Sony camera that cant do it...lol

Looking for more FS5 owners to chime in here!

CT

[Doug Jensen]

Cliff, look at the list of cameras you have mentioned. Those are nearly prosumer cameras compared to the higher-end XDCAM and Cine Alta lines. And the higher-end you go, the less people want to do a lot of in-camera sharpening. That is a fact. The FS5 kinda has its feet in both Sony product lines, and apparently Sony doesn't feel sharpening is a priority anymore. But with that said, even compared to the other high-end cameras, the FS5 doesn't allow very much detail control.

[Cliff Totten]

The concept of a "pro" image being "sharp" or not compared to a "consumer" image,...I literally have no opinion one way or the other on that. I think the terms "sharp" or "soft" are matter of style and artistic expression and who am to say that one is more "pro" and the other is more "consumer". I'm totally neutral on that idea.

I'm of the opinion that if there are settings on a camera, they should work to "reasonable" levels. If it has DETAIL and MANUAL SET parameters, allow them to operate in the manner that other Sony cameras do.

If s shooter likes them "soft" then turn them down. If a shooter likes them higher, then turn them up. Let the shooter decide, just like he/she can with other Sony cameras.

In Sony marketing materials, Sony, does market the A7s-II, FS5 and FS7 on the same advertisements.

I dont know, I'm a believe of: "Put the control there and let the shooter decide to use it or not"

I'm NOT a big fan of: "Put the control there but disable it anyway, for the good of he customer" If that's the case, just remove it from the menu system. No?

Who knows? Maybe I'm way out of line here. Maybe Sony is doing the right thing and I'm the one that is wrong?

CT

[Noa Put]

Most turn back sharpness in camera to add it again or not in post, from what I understand that is to minimize artifacts that incamera sharpening can cause, like maybe aliasing, so the user can decide in post what the end result should be.
I don't see a big deal in doing it this way, if you want to sharpen your footage, like you did in your comparison test, you can do that for your entire project in a few seconds, it's not that you need to visually check clip by clip, once you have determined the correct settings it's quickly changed.

[Cliff Totten]

All valid ideas Noa.

Other ideas to consider are: You are shooting to deliver the raw files to a friend or a client and they say "Hey, why are your FS5 files softer than my A7S-R/S files?"

What is my answer supposed to be? "Sorry, the FS5 sharpening controls are crippled by Sony because they don't want them being used by anybody"

Another thing is that sharpening plugins slow down renders. If the FS5 is "soft", I'd rather get it to match my other Sony models "in-camera" first and not have to touch that later in post.

Again.....If the parameters are there, (The many features inside MANUAL SET) they need to work. If it's true that Sony really, REALLY doesn't want those settings being used, they should just remove them. No?

Could you imagine if Sony had knee and slope controls that did nothing because they didn't want people to use them? They just left them there but disabled them?

Maybe that is not weird to some people but it seems strange to me.

CT

For anybody that hasn't seen it yet, here is the "soft" problem I'm talking about earlier: FS5 vs Z150 I think these image samples speak loud and clear. Next, I'll try an FS5 vs. A7s-II test. ("soft vs.sharp" test)

https://drive.google.com/folderview?...VE&usp=sharing