A7s highlight aliasing. Houston we have a problem
- Thread starter squig
- Start date
nyvz
Veteran
https://vimeo.com/99934720
Left shoulder
Can't say I'd be too keen on shooting models with this highlight aliasing
Watch the top of the park bench in the clip. Not really a problem on a 17" screen but I'd hate to see how the highlight aliasing looks on a 50ft screen!
I think you're mistaking oversharpening/detail for black pixel highlight aliasing to some degree. I don't see any in those except in the feet shot between her calves. The rest is just oversharpening.
squig
Veteran
It's certainly affecting sharp high contrast edges but it's also appearing inside an OOF blown out street light in ED's footage
Christopher Barry
Veteran
At 1.49, the "and" between "Shed and Fence"? If so, my observation is that Philip's 7GB file does not show any concerns to me when viewed on a 4K monitor at 1:1, and the 1080p Vimeo version at 1:1 viewing it is difficult for me to see an issue, the text is small, and when viewing the 1080 at full screen 4K, the "and" appears affected by re-compression, the Vimeo created 1080p file is a 70MB scale to 1080p.
As for the gutter at 1.20 I am observing no aliasing of concern with either of the aforementioned files. There is a slight waver in the gutter, it is not a completely straight line, and if anything, I would consider is a nice anti-aliasing type of result. This is my subjective observation, many variables why I may see a different image, and I don't mean that I am seeing an accurate image reproduction. Too many variables, possibly so many different monitor calibrations between us all. I just calibrated mine, it is taking a while to get use to, although I anticipated the warmer colour temp and reduced brightness from the 'Standard' setting from factory. I found the warmth of 6500 difficult to fathom when calibrating my first broadcast monitor system on an Avid 20 years ago. And my new glasses a few months ago, I am ready for a new set.
I am not seeing anything of concern in Philip's footage. Ed's footage has been significantly post processed with the grade/LUT work, and I would like to see source footage frames, such as a DPX export of some frames to compare end results before drawing any conclusions just yet. Interesting posts in this thread, Squig. Best to solve or understand any issues or limitation sooner rather than later, so glad you shared some observations. I may not have observed these in general viewing. Thanks.
As for the gutter at 1.20 I am observing no aliasing of concern with either of the aforementioned files. There is a slight waver in the gutter, it is not a completely straight line, and if anything, I would consider is a nice anti-aliasing type of result. This is my subjective observation, many variables why I may see a different image, and I don't mean that I am seeing an accurate image reproduction. Too many variables, possibly so many different monitor calibrations between us all. I just calibrated mine, it is taking a while to get use to, although I anticipated the warmer colour temp and reduced brightness from the 'Standard' setting from factory. I found the warmth of 6500 difficult to fathom when calibrating my first broadcast monitor system on an Avid 20 years ago. And my new glasses a few months ago, I am ready for a new set.
I am not seeing anything of concern in Philip's footage. Ed's footage has been significantly post processed with the grade/LUT work, and I would like to see source footage frames, such as a DPX export of some frames to compare end results before drawing any conclusions just yet. Interesting posts in this thread, Squig. Best to solve or understand any issues or limitation sooner rather than later, so glad you shared some observations. I may not have observed these in general viewing. Thanks.
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Bassman2003
Veteran
Between this camera and the GH4, I think everybody needs to chill out or up their budget! 
These incredible tools are under $3,000 and some have put them in the "not good enough" category already. If a camera does not create the image you are after, save up and buy a better one instead of trying to make a lesser model punch above its weight. Sorry to say this but this syndrome seems to get worse with every generation of improved cameras that are released.
These incredible tools are under $3,000 and some have put them in the "not good enough" category already. If a camera does not create the image you are after, save up and buy a better one instead of trying to make a lesser model punch above its weight. Sorry to say this but this syndrome seems to get worse with every generation of improved cameras that are released.
squig
Veteran
Between this camera and the GH4, I think everybody needs to chill out or up their budget!
Thanks for the sermon, but a lot of us are here to learn about the capabilities and pitfalls of cameras.
Bassman2003
Veteran
No worries. Not a sermon, just some perspective. These are CONSUMER cameras and still cameras at that. They are going to have flaws when expected to perform like professional video cameras.
As a side note, I would not use the overly stylized/graded footage as a demonstration of anything other than a look. Does this happen when you are shooting with your camera, ungraded normal footage?
Samuel H
Major Contributor
To me it also looks like too-much-sharpening, or at least an artifact created by some too-clever-by-a-bit algorithm (maybe for debayering or for downscaling the image). Settings may or may not get rid of this. It's a relatively minor thing, though, since it doesn't call the eye as other artifacts do (I find moire and FPN much more distracting than this).
squig
Veteran
It's seeing it on a 50ft screen that worries me. Plus it is a bug that should be squashed, nobody should have to live with it.
squig
Veteran
Can't say, my camera hasn't arrived yet but Kholi (my DSLR slave) should have one in a few days so we'll know soon. Lets not go the "professional" route, professionals use DSLRs on multi million dollar features, nuff said. It's a consumer camera marketed to people who shoot video and it's video has some bad pixels, something you couldn't complain too much about with a hack, but you certainly can with factory firmware.
squig
Veteran
Bad pixels are bad pixels. When we spot them in Magic Lantern the devs fix them and Sony should too. Their product is buggy, or as we say in Australia: a bit dodgy.
dfreerider
Well-known member
I agree. I appreciate people with better eyes than mine discovering potential flaws. Sometimes it turns out to be nothing serious, sometimes it does. A new camera should be tested to it's very limits, only then will we know how to get the best out of it.
The very reason we test these cameras and pixel peep, is so that we can discover what it is, worths and all. That way people can make informed buying decisions. Sometimes manufacturers are made aware of problems, and even take action, precisely because people called their attention to them.
To say it' just a 2500 USD camera, so we shouldn't look to hard at it, won't do us or the kid with filmmaking dreams who saves up for months to buy this camera any favours. Let us put it under the microscope and see what it can and can't do.
Christopher Barry
Veteran
The sample frames posted from Ed's footage, the grade may have eroded the detail between object edges and the light source, making it more high contrast. Detail in the source files may be where there are some steps now being observed. Punchy look, I like it in this instance. That's just me. Still valid to investigate.
millerandmiller
Member
Specular highlight artifacts / highlight aliasing has been around on the Sonys for years. The FS100 was the first camera I noticed it on. The FS700 has it when not going out through RAW. The F5/ F55 has it when the HD/2k image is not supersampled from 4k. Its the internal processing of these cameras, the 4k out of the A7s should be very clean and not suffer these issues. We will have to wait for the Atomos Shogun to see final results.
The crop mode on the A7s APS-C also appears to be clean.
It makes no difference what profile or sharpness is set it will be there. It's a little annoying sometimes but really its something that is going to be around on the Sony cameras for a while. Most of the time it's not a problem.
The crop mode on the A7s APS-C also appears to be clean.
It makes no difference what profile or sharpness is set it will be there. It's a little annoying sometimes but really its something that is going to be around on the Sony cameras for a while. Most of the time it's not a problem.
cyork
Well-known member
All I know is that I'm beyond excited to have a fs100/700 with better DR for $2500. This last film B&H sponsored film was pretty solid, though the grade wasn't how I would have left it. (crushed blacks, highlights but still really nice). Just playing around with the 3 way on the already graded footage, I can see lots of potential for some crazy nice grades.
http://vimeo.com/99972591
http://vimeo.com/99972591
Christopher Barry
Veteran
millerandmiller, yes, stefan outlined this back a few pages, thanks. Philip recorded 4K, the 7GB downloadable file appears fine to me, perhaps others may confirm, having more experience with this specific Sony issue.
4K for 2K 4:3 with wiggle room for stabilising and RS warp stabilising clean up, and some possible benefits of a small amount of scaling down. a7S and the Shogun potential at this price point is starting to blow my mind.
4K for 2K 4:3 with wiggle room for stabilising and RS warp stabilising clean up, and some possible benefits of a small amount of scaling down. a7S and the Shogun potential at this price point is starting to blow my mind.
eddavid
Carbonite Member
Good catch on all of that - and for the record I was shooting at -7 detail with s log on. If I have a chance I'll post a new grade - I've just been busy. Agreed if Sony can fix this lets ask them too - who is the people to contact at Sony to talk to them about this - I know Peter C. but I don't want to harass him if I don't need to.