Why Shooting 4K?

[hijodeibn]

The advantage of 4K is that you can re-frame or stabilize the shoots before downscale to 1080p, that is very useful, but if you have a very good HD cam and you are good framing during the shooting, no much difference to be honest…. 

[mercer]

8 hours ago, jonpais said:

Looking forward to seeing some of your footage. 

Passive aggressive much?

I both love and hate this discussion because I have seen first hand that in the end it doesn't matter. I think a lot of people want to justify their purchases and decisions and that leads to heated discussions on a gear related forum.

So if someone wants 4K, shoot in 4K. If someone wants 1080p, shoot in 1080p.

Hell, your 1080p ProRes footage is way better than the sooc 4K footage from the same camera... so there are obviously other factors at play instead of 4K vs 1080p.

And no matter what a filmmaker does with consumer 4K, straight out of camera, I think they would be hard pressed to get an image as cinematic and beautiful as the screenshot @enny shared. That shot looks epic.

[mercer]

10 hours ago, enny said:

i man you can get a nice camera for 3000 does not have to be 4k. You can get full BMCC for under 3k. I just seen  few frames of a dp this frame was captured on BMCC 2.5k raw notice cinematography not 4k 6k 8k i mean it looks beautiful (http://www.bmcuser.com/showthread.php?20700-Frames-from-short-film-I-m-Dping)

Yeah, I am blown away by that shot. This is the perfect example for the anti 4K argument. Obviously the DP and colorist need to be commended here, but I don't think this would be possible with a consumer 4K camera. The GH5 may get you close, but I doubt the highlights would look as good. 

[jonpais]

@mercer I agree with @enny that lights and glass are a better investment than continually upgrading cameras. There would probably be no argument that audio would also be a better place to spend money. For sure, content is king, no question about that, either! Any discussion about gear can come to a grinding halt by bringing that up. But quite frankly, from this screen grab alone, I'm not seeing anything the Samsung NX-1 couldn't do equally well, if not far better. Graded shots can hide weaknesses and play up on the strengths, not only of footage, but also field tests of lenses: so judging cameras and glass solely from screen captures of edited work is a bit hazardous. Getting back on topic, I don't see what worldwide sales of television sets has to do with anything. Same for 4K monitors - just because my neighbors don't have a 5K iMac is no reason why I can't enjoy mine (it's supposed to arrive next week!); and this goes for the lucky few here who own 65-inch displays as well. Also, in my posts, I was referring to mirrorless cameras, not cinema cameras.

AFAIK, the BMCC is best suited to narrative work - the form factor pretty much means it needs to be mounted on a tripod or shoulder rig; it's got a crop sensor smaller than micro 4/3 (2.3X crop), which will cause difficulties with FOV and bokeh and which is probably its biggest drawback, at least as far as I'm concerned; the cost of SSD storage is going to add up quickly; you're going to need a powerful machine to edit the RAW files; you can't delete clips from the camera or format the SSD in camera: it's got a passive mount; no custom WB; cannot set shutter speed, only shutter angle, so avoiding strobing might be a problem; no audio levels; ISO is fairly limited (200-1600); not great in low light; file sizes are humungous (RAW 35 min. 240GB SSD, which you should also be backing up on at least one extra drive at the office or at home); the internal battery life isn't great, so you'll need a battery solution; no phantom power for microphones; RS is an issue; no high frame rates; focus peaking is not totally reliable; and the LCD has a lot of glare - ideally, you'd be using an EVF or external monitor. I should add that I've never handled the camera, this is all what I've gleaned from watching several reviews online, and that some of these issues may have already been addressed by firmware updates.

[mercer]

@jonpais I agree with some of that. I think you would be hard pressed to get NX1 footage to have the same depth, texture and highlight roll off as shown in that screen grab, though but maybe. 

As I said earlier, I think people should use whatever camera they feel comfortable with. If they like 4K, then they should shoot 4K. If they like 1080p or can only afford 1080p, then shoot with 1080p.

In the 2+ years I've been around here, I have learned a ton, but I've also learned that I am not a particularly talented or skilled operator, but I love filmmaking. I was ready to quit it all as it was becoming way too expensive of a hobby without getting results I felt comfortable with. And then I made a Hail Mary pass and bought the 5D3 and it all came together for me. I'm still not nearly as talented or skilled as I'd like to be, but at least I can look at my shots and not feel angst.

But even with that gratification I missed small cameras and small file sizes. So I convinced myself that I needed a small mirrorless 4K camera for casual video, or at least a camera that has IBIS. I bought and sold, or returned, a few more and have never been happy with the results. To this day, I have only liked the images I was able to shoot with either my D5500 or my 5D3. I made a couple 4K videos from my NX500 days that were okay, but I had plenty more failures than successes with that camera.

 So when I speak of 4K vs 1080p, my opinion is based solely on my very specific history with various cameras and my skill set with using them. And my only interest in video is for narrative work. I could not care less about any other form of videography and what is deemed acceptable or even beautiful for those disciplines.

With that being said, I wish you could get your hands on a 5D3 or a BMCC for a week to give them a test ride. I think you would have a different opinion of them and 1080p when seen in Raw. You already have seen how beautiful 1080p ProRes is. 

Or get, or borrow, a BMPCC and put one of those fancy 12mm lenses you have on it, I think you'd be blown away by it. 

[Shirozina]

Some cameras can capture 1080p nativity that looks good when displayed on a 1080p device. Other cameras need to capture at a higher native resolution in order to produce good 1080p. Shooting with a higher resolution than the output is perfectly normal in stills photography and the same applies to video. More resolution than the output size allows re-framing, straightening, image rectification and stabilisation in post production without compromising the resolution. When 4k output becomes the norm then likley 6/8k capture will be required......

[joema]

22 hours ago, hijodeibn said:

The advantage of 4K is that you can re-frame or stabilize the shoots before downscale to 1080p, that is very useful, but if you have a very good HD cam and you are good framing during the shooting, no much difference to be honest…. 

This is correct, and (once again) the OP equated 4k solely with distribution resolution. There are several reasons to shoot 4k:

(1) Allows reframing in post

(2) May allow better stabilization in post provided the shot is framed a little loose. OTOH digital stabilization often induces artifacts so the goal is not use this.

(3) Each frame is an 8 megapixel still so frame grabs are a lot better.

(4) Shooting in 4k may give better "shelf life" for the material, similar to how shooting TV color did in the 1960s. Even though initially few people had color TVs, eventually everyone would so the additional cost of color film was often worthwhile.

(5) Large 4k productions impose a major new post production load. It is vastly harder than 1080p due to the volume and possible transcoding and workflow changes. When my doc group shot H264 1080p we could just distribute that in the post-production pipeline without a thought. With H264 4k, it must be transcoded to proxy, collaborative editing often requires a proxy-only workflow which then can expose complications for re-sync, etc. The reason this is an argument *for* 4k is it takes a long time to figure out the post production issues. Computers won't be much faster next year, so if you're *ever* going to transition to 4k and are shooting multicam and high shooting ratio material, you may as well start the learning curve now.

Arguments against 4k: It may not look much (or any) better than good quality 1080p when viewed on typical playback devices, so why take the huge hit in post production. It can actually look worse than 1080p, depending on what cameras are used.

Even though #5 above was listed as a 4k advantage, this is also one of the strongest arguments *against* 4k: the huge post production load. Whether you shoot in ProRes, DNxHD, H264, etc. it can be a huge burden. Worst of all is H264 since few computers are fast enough to smoothly edit this. Therefore it generally requires transcoding, proxies, and various knock-on effects regarding media management. It's not that bad if playing around with 4k or shooting a little commercial, but for larger productions I'd roughly I'd estimate it's over 10x (not 4x) as difficult as 1080p from an IT and data wrangling standpoint.

[dantheman]

Much depends on who your clients are and what you use the camera for, I mainly shoot weddings and 4K had given me nothing but advantages:

I am selling a 4K file to my clients since this year (for 2018-19 weddings) as a paid option, About 7 out of 10 clients takes it, not because all are able to benefit from it now but they will in years to come. 4K might not be "standard" now but it eventually will be. Some of my clients do have a big 4K screen, I have one too to showcase 4K, 4K on a big screen looks much nicer then 1080p does.

I often get the question if it's not possible to take framegrabs from my films, it is not a substitute for photography but it can be an addition for shots the photographer have missed and a 4K framegrab is a lot better then a 1080p one when they want to print photos.

I also take framegrabs from 4K footage for prints that I use on my blu-ray's, I used to take photos but now I don't have to switch anymore and just concentrate on video and take out high rez framegrabs out afterwards, instead of 1 photo I now have 25 photos every second to choose from.

The weddings I shoot this year are still delivered in 1080p and there I make use of the cropping ability in post which can make a difference if you are a solo shooter, I know I will loose that option once I deliver in 4K but that inconvenience is quickly forgotten if I see that I can charge 20% on top of my package price for almost no extra work. There will come a moment that 4K might be standard and I can't charge extra for it anymore but that I feel is still a few year away.

My clients always get a 1080p file as well, together with the 4K one if they have choosen for that and downscaled 1080p from 4K looks better then when I shoot 1080p, I have several 4K capable panasonic camera's and they all produce better looking footage in 4K with less artifacts.

My workflow is hardly affected, I do have more data to handle (a average wedding is between 200 and 350GB) but it doesn't slow my workflow down, I edit all my 4K files natively in Edius and in real time on a 3 year old computer, this includes multicam and colorcorrecting my footage or applying luts. Exporting is also very fast since Edius uses quicksync to accelerate rendering.

So as you can see for some areas 4K has it's benefits but I can understand it doesn't have the same advantages for many others.

[HockeyFan12]

I've never been that bullish on 4k video or it providing a significant or worthwhile improvement in real-world use. For UI elements on phones and computers I think a high res display is advantageous, but 4k video doesn't look significantly better to me at normal viewing distances (except maybe for line art and 2D animation). I recall that the text on my projector from my PS4 looks pixellated but the video never does. For VR I think higher resolutions are going to be particularly important, for video and UI elements alike. 

The statistic you posted is misleading. Most of us are in the US or developed countries that have at least a majority HD infrastructure and even if we're selling to other markets that don't have HD, those markets are less important to our revenue stream. I think all of us benefit from shooting HD. I think most of us know whether our clients will pay more for 4k and it's really just a cost-benefit analysis at that point. Or as hobbyists, we decide that cost-benefit analysis subjectively. 

Personally, I prefer working with 2k or 1080p media both professionally and as a hobby. I hate doing the extra busy work or waiting on the extra renders and I don't see any difference in real-world use. I just don't see the difference, but my eyes are now 20:30 or 20:20. When I was young and they were 20:15 I bet I tell the difference even with video at a normal viewing distance. I do think VR video is too low res now and that will need to be acquired at 8k or 16k or beyond to look good. 

I don't personally expect that most tv networks will upgrade their infrastructure to 1080p in the US or abroad. Upgrading to HD was recent and very expensive. Their libraries are all 1080p anyway, and finished as such. But I do think tv will eventually be displaced by Netflix, YouTube, Amazon, etc. which already have 4k infrastructure. So watching how that market changes and evolves and tracing those viewership graphs will probably give a pretty good idea when 4k will become widely demanded. CBS won't push its shows to 4k for air. Not ever, I think. But Netflix might push them to shoot in 4k so they can license a 4k deliverable for their own distribution.

When networks earn more money from licensing 4k to Netflix than they suffer in added production cost shooting in that format (fwiw, the added cost is deceptively enormous for larger productions), we'll see a quick change. That won't be too soon. But it will happen soon enough. Probably sooner than we think! I bet Arri is targeting a true 4k Alexa for before that date.

Personally, I'm in no rush at all to upgrade, but that's just me! I know a lot of people here are primarily targeting Netflix Original distribution (based on posts I've read). I still think 1080p is fine for that. They'll acquire 1080p movies as originals; they just won't produce 1080p series. So I wouldn't worry about that. 

TL;DR: People shooting 4k did a cost-benefit analysis and 4k provided more profit from their clients, which in that case are the only clients who matter, or they just want to because they're hobbyists, in which case their preferences (and bank account) are all that matter.

[jcs]

One reason many folks don't see that much of an improvement in quality of 4K vs. 2K/1080p, is that most cameras aren't actually capturing true 4K. It's the same reason cameras that capture in 4K and downscale to 1080p can look better than cameras that shoot 1080p: the 1080p cameras (or modes) aren't actually capturing true 1080p. Per Nyquist, we need 4K photosites to capture true 1080p (Bayer sensor), and 8K to capture 4K. Just like the 8K F65 being the first 4K camera to capture close to true 4K, the F35 also used double the number of photosites to capture 1080p (and actually triple horizontally). See this post for more details and images: http://www.dvxuser.com/V6/showthread.php?318627-F35-Beginners-What-is-the-sensor

Note that with a 4K sensor, the Canon C300 I was rated by Canon just over the theoretical limit (960) at 1000 TV Lines (1920/2 = 960 (/2 = Nyquist)): https://www.canon-me.com/for_home/product_finder/digital_cinema/cinema_eos_cameras/eos_c300/specification.aspx. So "1000 or more TV Lines" includes aliasing, and indeed the C300 I aliases on fine detail.

The Sony F3 also has excellent 1080p, getting 540 line pairs or 1080 TV Lines (horizontal pixel resolution: 1080 might be confusing since it's the same as the native vertical resolution: just a coincidence unless they used an OLPF to get that specific value):

Thus it may be the case that until more 4K cameras have 8K sensors, the jump in 2K/1080p to 4K quality won't be as dramatic for most people. The same pattern as when people began to realize their 1080p wasn't true 1080p until shooting in 4K and downsampling to 1080p in post.

[HockeyFan12]

JCS, can you stop propagating that incorrect version of the Nyquist theorem? If you want I can link you to the original thread where Graeme Nattress at Red describes how it actually works. If you agree to take a look at it I'll leave you alone about it, since usually you're a valuable contributor, but I hate to see that kind of misinformation spread online in a technical forum.

[jcs]

48 minutes ago, HockeyFan12 said:

JCS, can you stop propagating that incorrect version of the Nyquist theorem? If you want I can link you to the original thread where Graeme Nattress at Red describes how it actually works. If you agree to take a look at it I'll leave you alone about it, since usually you're a valuable contributor, but I hate to see that kind of misinformation spread online in a technical forum.

Do you have a 4K test chart showing 4K lines captured without aliasing (Nyquist says 2K before aliasing)? Until then, every single online technical discussion by camera/microscope companies show Nyquist /2, including Canon stating ~1000 TV Lines resolution possible (horizontal pixels; Nyquist is 1920/2 = 960, so 40+ pixels will be starting to alias) in 1920x1080 from the 4K Bayer array on the C300 I.

Happy to review Red's description- I suspect some kind of misunderstanding in terms somewhere.

[HockeyFan12]

Sure, here's the thread. It's a long one. I do think it's a bit presumptuous of you that you think you understand this better than Red's chief imaging engineer, but I've been called presumptuous too. Graeme explains to someone (a somewhat presumptuous poster named Matt) why the same misunderstanding you have is, in fact, a misunderstanding:

http://www.reduser.net/forum/showthread.php?157330-Is-this-chroma-aliasing

There's a lot to get through, much of it noise and ad hominem bullshit, but it's all there. Posting this thread is a little embarrassing for me since I clearly can’t articulate how Nyquist works as well in a half dozen posts (in an earlier thread) as Graeme can in a few paragraphs, but hey. I can swallow my pride for a moment and let Red's chief engineer do his thing.  

And no, I don't have that test chart in front of me, but I assure you that a 4k sinusoidal zone plate would not alias on a 4k Foveon or monochrome camera while a 4k binary (square wave) zone plate would. And if you want to order and ship me a 4k sinusoidal zone plate (they're expensive as heck) I would be glad to prove it.

Fwiw, the image you posted above specifies line pairs per sensor height. Not width. Height is the 1080 pixel axis, not the 1920 pixel axis (in 1920X1080).

Pairs are one white pixel and one black pixel. 

So if the F3 resolves 540 line pairs, then it resolves 1080 lines.... at 1080p.

Which makes sense. The F3 oversamples by about 1.5X on each axis (like the Alexa) and it has a Bayer sensor. Bayer interpolation is about 70% efficient, and 1.5*0.7 is about 1. So you get full resolution in each axis. Which is to say 1080 lines in the vertical axis and 1920 in the horizontal axis. Which is to say 540 line pairs per sensor height.

Which is exactly what that chart predicts. Because the real world correlates with the real Nyquist theorem.

[jcs]

3 minutes ago, HockeyFan12 said:

Sure, here's the thread. It's a long one. But Graeme explains to someone (a somewhat presumptuous poster named Matt) why the same misunderstanding you have is, in fact, a misunderstanding:

http://www.reduser.net/forum/showthread.php?157330-Is-this-chroma-aliasing

This is a little embarrassing for me since I clearly can’t articulate this as well in a half dozen posts as Graeme can in a few paragraphs, but hey. I can swallow my pride for a moment and let Red's chief engineer do his thing.

And no, I don't have that test chart in front of me, but I assure you that a 4k sinusoidal zone plate would not alias on a 4k camera while a 4k binary (square wave) zone plate would.

This is wrong, especially the bold (emphasis mine), from: http://www.reduser.net/forum/showthread.php?157330-Is-this-chroma-aliasing/page2&s=73723d93a5062b3cc1c05cd4e21f54e3

Quote

Let's start with the simplest case - a monochrome sensor. Say it's a 4k sensor. Sampling theory would say you need a sampling frequency at least double that of the sampled waveform to avoid aliasing. In other words, you need at least two samples per wavelength. If we think of a wavelength as a pair of lines, one white, one black we can re-state it as saying we need at least two samples per line pair. As a line pair contains two lines, we can now see that we need at least two samples per two lines, or a sample per line. A 4k mono sensor has 4k lines and thus there is no violation of sampling theory by getting 4k resolution from it (strictly < 4k resolution would be correct, but any resolution up to but not including 4k would be valid).

Each pixel is a sample, and we need at least two samples per pixel to represent the finest detail possible without aliasing (3 pixels would be better).

If Red's statements were true, you'd have no trouble finding HD sensors resolving 2000+ lines or 4K sensors resolving 4K+ lines: where are the test charts or manufacturer spec sheets showing this? The practical limit for HD is around a 1000 lines, and for 4K is around 2000 lines (horizontal resolution) before aliasing becomes significant.

[HockeyFan12]

9 minutes ago, jcs said:

This is wrong, especially the bold (emphasis mine), from: http://www.reduser.net/forum/showthread.php?157330-Is-this-chroma-aliasing/page2&s=73723d93a5062b3cc1c05cd4e21f54e3

Each pixel is a sample, and we need at least two samples per pixel to represent the finest detail possible without aliasing (3 pixels would be better).

If Red's statements were true, you'd have no trouble finding HD sensors resolving 2000+ lines or 4K sensors resolving 4K+ lines: where are the test charts or manufacturer spec sheets showing this? The practical limit for HD is around a 1000 lines, and for 4K is around 2000 lines (horizontal resolution) before aliasing becomes significant.

Then why does the image you recently posted show 540 line pairs (1080 lines) in the VERTICAL (not horizontal) resolution for the F3? Exactly as my model would predict from a full raster 3 megapixel sample downscaled to 1080p? And 848 line pairs for the Alexa in RAW, very close to the figure my model would predict (it would predict 1620 lines from a 2880X1620 sensor, or 810 line pairs–the difference between 810 and 848 could be aliasing reading as false detail).

Edit: also, that wasn't long enough to read a four-page thread. Go back and read it all. I had my questions, too, at first, until I got into the difference between sinusoidal and binary zone plates.

Anyhow, I'm done. Everything except online banter agrees with what I've posted, including repeatably real-world behavior (science) and numbers (math). If you want to take this up with Graeme I encourage you to, but I just wish you wouldn't freely post misinformation like this.

[jcs]

9 minutes ago, HockeyFan12 said:

Then why does the image you recently posted show 540 line pairs (1080 lines) in the VERTICAL (not horizontal) resolution for the F3? Exactly as my model would predict?

Line Pairs per Sensor Height is confusing and doesn't mean what you think it does. Line Pairs per Sensor Height = TV Lines = horizontal resolution. Note in this article, the C300 I is said to have basically the same resolution as the F3: http://nofilmschool.com/2011/11/canon-cinema-eos-c300-4k-sensor-outputs-1080p 1000+ TV Lines ~= 540 LPpSH ~= 1080 TV Lines (horizontal resolution).

[HockeyFan12]

13 minutes ago, jcs said:

Line Pairs per Sensor Height is confusing and doesn't mean what you think it does. Line Pairs per Sensor Height = TV Lines = horizontal resolution. Note in this article, the C300 I is said to have basically the same resolution as the F3: http://nofilmschool.com/2011/11/canon-cinema-eos-c300-4k-sensor-outputs-1080p 1000 TV Lines ~= 540 LPpSH ~= 1080 TV Lines (horizontal resolution).

Even if that were the case, Graeme's model would still be correct in terms of the math and theory. (Nyquist requires >2 samples per sine wave, not >4 samples per square wave, as your version amounts to. If you look into how it's applied to audio this will be clearer.)

But, anyhow, it isn't the case:

https://en.wikipedia.org/wiki/Television_lines

Wikipedia agrees with you that tv lines are traditionally measured in horizontal lines, and they are, but they note that the measurement is "alternatively known as Lines of Horizontal Resolution (LoHR)" (emphasis mine). Horizontal. Not vertical. That test was of vertical lines!

So either Graeme is wrong and either wikipedia or whoever made that chart is wrong or all three actual authorities on the subject are right you're wrong. And given that your definition of Nyquist is inaccurate at a very basic level (when it cites "frequency" it refers the highest order frequency, which in the case of the sine wave is its fundamental but in the case of a square wave is the highest order harmonic, and when it refers to cycle it means line pairs, not lines) I have to go with them. And with reason. Read all of Graeme's replies. He really thought through his argument, and it makes sense.

[jcs]

2 minutes ago, HockeyFan12 said:

Even if that were the case, and it isn't, Graeme's model would still be correct in terms of the math and theory.

And it isn't the case:

https://en.wikipedia.org/wiki/Television_lines

Wikipedia agrees with you that tv lines are traditionally measured in horizontal lines, and they are, but they note that the measurement is "alternatively known as Lines of Horizontal Resolution (LoHR)" (emphasis mine). Horizontal. Not vertical.

So either Graeme is wrong and either wikipedia or whoever made that chart is wrong or all three actual authorities on the subject are right you're wrong. And given that your definition of Nyquist is inaccurate at a very basic level (when it cites "frequency" it refers the highest order frequency, which in the case of the sine wave is its fundamental but in the case of a square wave is the highest order harmonic) I have to go with them. And with math. And with science. 

Haha what are you smoking, dude? Did you read the NFS article stating the F3 and C300 have the same basic resolution. Canon states 1000 TV lines (are they wrong too?), NFS matches the F3 with 540 LPpSH = 1080 TV Lines, isn't that clear? Or are they wrong too?  http://nofilmschool.com/2011/11/canon-cinema-eos-c300-4k-sensor-outputs-1080p

All you have to do is produce a test chart showing a 4K sensor resolving 4K lines to prove your point.

[HockeyFan12]

Indica, at the moment. 

And I don't have to prove my point to anyone but you, because everyone else gets it. At least the people who matter, like Graeme and whoever put that test together. I just wish you wouldn't spread this kind of misinformation online. If you want to you're free to but there's already enough misinformation out there. Case in point, that article confuses vertical and horizontal lines of resolution.

So did you.

Buy me a 4k sinusoidal (not square wave) zone plate. (Let's keep the budget at $500 or less.) I'll photograph it with a Foveon camera, center crop 4k. If the behavior correlates more closely with the model I correctly cite than the one you made up, you eat the cost of the zone plate. If it correlates with your claims, I'll pay you back. We can accept a small margin of error either way due to other real world factors (quantization error, things not being perfectly aligned). But our models are vastly different so we should see one or the other clearly prevail. 

I'm dead serious. But keep the zone plate to $500 or less I have rent to pay and am saving up for a house. :/ 

[jcs]

1 minute ago, HockeyFan12 said:

Indica, at the moment. 

And I don't have to prove my point to anyone but you, because everyone else gets it. At least the people who matter, like Graeme and whoever put that test together. I just wish you wouldn't spread this kind of misinformation online, but if you want to you're free to. That article confuses tv lines of resolution (what Canon mentions) with vertical lines of resolution (what the test measures). That article made a simple mistake. So did you.

Buy me a 4k sinusoidal (not square wave) zone plate. (Let's keep the budget at $500 or less.) I'll photograph it with a Foveon camera, center crop 4k. If the behavior correlates more closely with the model I correctly cite than the one you made up, you eat the cost of the zone plate. If it correlates with your claims, I'll pay you back.

I'm dead serious. But keep the zone plate to $500 or less I have rent to pay. :/ 

Why isn't there anywhere else on the internet saying the same thing as Graeme?

Very simple, 4K test chart showing 4K lines or bust. Or 2K test chart showing 2K lines or bust.

Lol, now I have to send you money so you can prove your point?