AVS Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
72 Posts
Discussion Starter · #1 ·
I just took delivery of the awesome AX100. I've been considering the GH4 (as I've had the GH3 and GH2 before it), but I also enjoy the convenience of the camcorder form factor. I'm no pro videographer, more of a gadget geek that enjoys casual video shooting...so that's my perspective.


A friend of mine and I got together and wanted to compare how they all look at 1080P. I tested the ax100 in 4k downsampled to 1080, in 1080 native mode and compared it to a GX7 (with 14-140 5.6), the RC10 and a Panasonic HC-X900. I left the sound in the clip so you can get a feel for that too...it was 62F here today with still plenty of snow around, so you can here the dripping in the background as well as my voice.


Obviously no art here...just a super stress test of a camera and lens with the fine branches and bright sky. Conditions changed a little as I was doing it, so nothing is conclusive. I used each camera at it's widest setting, left everything auto. Sky was, for the most part, high overcast, so there really was no detail in the sky to recover so no exposure compensation was used.


Overall, the AX100 4k resampled (using handbrake) just killed everything else. The AX100 native 1080 and RC10 were very similar. The other were distant followers from a sharpness standpoint.


I decided against the RX10 due to the horrible Steadyshot...even active is a mess. the AX100 is better, but I don't know what Sony's been smoking lately to screw up their steadyshot in their top cameras.

https://www.youtube.com/watch?v=h4NCHx5s2ak


I also have full res screenshots to give you a better idea of the quality (since youtube makes it look like barf).

ax100_4k_to_1080.jpg 957k .jpg file
ax100_1080.jpg 827k .jpg file
gx7_1080.jpg 853k .jpg file
rx10_1080.jpg 784k .jpg file
hc-x900_1080.jpg 841k .jpg file


Rick Krejci
 

Attachments

·
Registered
Joined
·
389 Posts
Thanks for the great comparison - it's really rare that someone does these comparisons and they are very, very revealing - in this case they show the AX100 4k resampled to 1080 just kills everything else in sharpness and detail like you said. So the great question yet to be tested and answered is: Does 4K footage from the GH4 resampled to 1080 look competitive with the AX100? It's an important question for those of use that have a need to use an interchangable lens camera.
 

·
Registered
Joined
·
349 Posts
Hi


Thank you for taking the time to test these.


What I notice straight away is the over sharpening in the 4K resized frame, this is becoming quite common on the AX100 4K footage. This is either applied by the camera, or during the resizing, or both. So when comparing the 1080P native frame and the 4K resized one, there appears to be a bigger difference in detail captured than perhaps there is.


I've sharpened very quickly the 1080P AX100 still and attached it to compare more like for like with the 4K one, unfortunately I don't have the original frame so the sharpening is showing up the JPEG compression, but you can see the differences are now not as large. You can see the sharpening level is similar on the 1080P file now as the 4K one, look at the right hand side hanging light and the halos around the metal against the lighter glass, and you can also see a halo around the metal against the snow. All this is already present on the 4K frame, but not the original 1080P frame which implies no sharpening, or very little applied.


There is certainly a difference in the detail captured in the trees and leaves, 4K resized is always going to resolve more detail as you have some extra color information interpolated during the re-sizing.


How is the 1080P captured was it 50Mbps data-rate or standard AVCHD? Also the longer GOP if 60fps recording may mean if you find something closure to an I frame or the actual I frame, there will be more detail to be had.


Sitting back and looking at both the images with equal sharpening the 1080P is holding up pretty well against the resized one, and given the 1080P can play back at 60fps, the likely hood is we will resolve more detail during motion than is possible with 24fps.


Overall I think people shouldn't be scared of 1080P from the AX100, there is no need to shoot 4K if all you want is 1080P which comes with 60fps and will look super smooth and realistic, not something you can see from YouTube clips as that butchers everything to 30fps or less.


Regards


Phil

ax100_1080withsharpnessapplied.png 3891k .png file
 

Attachments

·
Registered
Joined
·
72 Posts
Discussion Starter · #4 ·
I've provided you with original frame captures as attachments. And, yes, I think the 1080P footage is undersharpened. I think the original 4K footage is certainly not oversharpened. I think the handbrake conversion of 4K to 1080P seems to have picked up some sharpening, but not over the top. I did a comparison of several converters I had on hand, and actually Nero provided the most natural looking conversions. Adobe Premiere Elements and Handbrake were very similar...a little more sharpening, but still pleasing.


But comparing your sharpened frame to the 4k->1080 frame I provided (as well as taking the 1080 frame capture I provided and running through some light sharpening), the amount of fine detail in the native 1080P frame isn't in the ballpark of the 4k. And yours is indeed loaded with sharpening artifacts. The 4k->1080p looks much more natural and pleasing with loads of detail but not painful to look at like yours.


I will agree not to be scared of the native 1080P, though. It is about the best of the best out there for 1080P cameras and as you say can provide 60P which can be great for dynamic scenes. But 4k 30p will be my default and will only drop to 1080 60P if the need arises.
 

·
Registered
Joined
·
349 Posts
Hi


The frames here that you attached as downloads are JPEGs, so they are further compressed by a lossy compression algorithm, this is what I meant by not being the originals. The artifacts on the 1080P will be added by the JPEG compression then brought out by sharpening. I didn't use an unsharp mask or anything sophisticated, it is bog standard sharpening and probably too heavy. What was the recording bit-rate for the 1080P footage out of interest?


Any sharpening at acquisition and burnt into the original is too much. Sharpening is a lossy process, and while the optical illusion is that we think we see more detail, in reality there is less, and once sharpened you can't unsharpen again.


A lot of footage (4K or other) from more professional cameras that has been graded and then uploaded typically has very little or no sharpening, and then everyone falls over themselves how good the AX100 looks in comparison against these professional cameras with claims of lots more detail for the AX100, however the detail is false and the comparison isn't a true one.


I've seen the native clips from the AX100 and there is sharpening all over the place in 4K. It is silly for the camera to add it as it just makes the compression less efficient, but just like TVs with their retina burning "buy me" settings, the Sony AX100 has the same treatment, still it is aimed at consumers and this is par for the course. The only place sharpening should really be added is by the display device and then it can be to the viewers taste.

http://www.videophile.info/Guide_EE/Page_01.htm


Regards


Phil
 

·
Registered
Joined
·
33,553 Posts
Rick, you're knocking your head against the wall with Phil on the subject of either over-sharpening or 30p. No matter how many owners say there is no over-sharpening, he will continue to say there is. And 30p? Don't even try to go there. Phil has a habit of posting either pixel-peeping frame grabs of a moving video to show any artifact he can find in an AX100 4K video (a really inane way to try to 'prove' the AX100 video is flawed) or, as you saw, an unrealistic 'representation' of over-sharpening. You'll see this no matter where he posts or whatever forum he's posting in.


I can see little use for shooting in 1080p with the AX100 when with 4K we have:


* Archived 4K resolution for future use whenever you get a 4K display. When you see the true 4K on a UHD display, you'll be wowed that much more. Fantastic detail with no over sharpening.

* Obviously better detail than any native HD camera when the 4K is down-sampled to HD. Virtually everyone can see this but one poster. It's REAL detail, not imagined, not 'apparent' because of some imagined 'over-sharpening'.

* Superior color information in the HD down sample

* Using the frame rate doubler in almost any modern HD or UHD TV, the motion of 30p can be smoothed to look very nearly like 60p. It really is that good.


Of course there's nothing wrong with shooting in HD if you absolutely have to have 60p. For me, the disadvantages of doing that far outweigh the advantages. Especially when I can do such a good job simulating 60p with either of my HDTVs frame rate multipliers.
 

·
Registered
Joined
·
33,553 Posts

Quote:
Originally Posted by Philip_L  /t/1525210/1080p-comparison-with-various-cameras-ax100-rc10-gx7-x900#post_24556945


Any sharpening at acquisition and burnt into the original is too much. Sharpening is a lossy process, and while the optical illusion is that we think we see more detail, in reality there is less, and once sharpened you can't unsharpen again.


A lot of footage (4K or other) from more professional cameras that has been graded and then uploaded typically has very little or no sharpening, and then everyone falls over themselves how good the AX100 looks in comparison against these professional cameras with claims of lots more detail for the AX100, however the detail is false and the comparison isn't a true one.


I've seen the native clips from the AX100 and there is sharpening all over the place in 4K. It is silly for the camera to add it as it just makes the compression less efficient, but just like TVs with their retina burning "buy me" settings, the Sony AX100 has the same treatment, still it is aimed at consumers and this is par for the course. The only place sharpening should really be added is by the display device and then it can be to the viewers taste.

You can say this until your blue in the face Phil and I'll be there to counter every distortion-filled post you make. This is really bordering on an obsession with you and your one man campaign against the AX100.


Did you know on another forum the AX100 was compared in an A/B with the BMC 4K camera and guess what? The AX100 resolved more detail than the BM. It was not over-sharpened, it was not 'imagined', it was REAL DETAIL Phil, REAL DETAIL. Writing could be easily read on a propeller where the same footage on the BM could not. The shooter who did this test was shocked and decided, based on what he SAW, that he was keeping the AX100. False detail? That's simply untrue Phil.


BTW, some of those more expensive 4K cameras that you so highly tout, ARE lacking detail. It has nothing to do with sharpening or not sharpening, some of them are simply NOT resolving the detail the AX100 does. Sorry buddy, but that's the truth and most can see it. You can't read text that's not there and no amount of over-sharpening will make text more legible, but detail will, the ability to resolve detail will. You don't seem to understand the difference or there is something radically wrong with the equipment you view this stuff on.


Wake up Phil, wake up. You are the only one on any forum that has this obsession with knocking the AX100. I wonder why? You have absolutely no idea of what you're talking about. You've never seen native AX100 footage on a large screen HDTV. You've never AX100 footage on a large screen UHD TV. Yet you are an expert on everything AX100. Absolutely unreal.


Several people have asked you to provide a good 4K video that YOU think is great and without artifacts. We wait...and wait....and wait.
 
1 - 7 of 7 Posts
Top