Sony FDR-AX100

[Glen Vandermolen]

Does the AX100 have timecode?

[Alister Chapman]

Video sensor size measurement originates from the first tube cameras where the size designation would have related to the outside diameter of the glass tube. The area of the face of the tube used to create the actual image would have been much smaller, typically about 2/3rds of the tube diameter, so a 1" tube would give a 2/3" diameter active area, within which you would have a 4:3 frame with a 16mm diagonal.

An old 2/3" Tube camera would have had a 4:3 active area of about 8.8mm x 6.6mm giving an 11mm diagonal. This 4:3 11mm diagonal is the size now used to denote a modern 2/3" sensor. A 1/2" sensor has a 8mm diagonal and a 1" sensor a 16mm diagonal.

Yes, it's confusing, but the same 2/3" lenses as designed for tube cameras in the 1950's can still be used today on a modern 2/3" video camera and will give the same field of view today as they did back then. So the sizes have stuck, even though they have little relationship with the physical size of a modern sensor. Hence the term, 1" Type, as it is an active area that would be the equivalent to the active area of an old 1" diameter Vidicon/Saticon/Plumbicon Tube from the 1950's.

For comparison:

1/3" = 6mm diag.
1/2" = 8mm
2/3" = 11mm
1" = 16mm
4/3" = 22mm

A camera with a Super35mm sensor would be the equivalent of approx 35-40mm
APS-C would be approx 30mm

[Adriano Moroni]

Originally Posted by Alister Chapman

Adriano. Your problem is almost certainly aliasing. If you simply re-size a higher resolution image down to a lower resolution image without some processing to eliminate aliasing (such as adding a slight blur to the high resolution image before down scaling or a proper anti-aliase process) you will get a lot of excessively sharp and jagged edges, especially fine details and textures that will flicker and not look good. It's not the camera, it is your workflow.

If I understand fine, the best way is that I have to add a slight blur to those flickering clips on the timeline. As I have many of flickering clips I'd like to know if even you get some flickering clips.

Edit: I am very worried. I did some tests with both the filter, blur and ati-flicker. Hard blur filter and Anti-flicker 100% filter, both filters improve very slightly the flickering but they don't eliminate it at all. And after it the image deteriorates a lot.

[Noa Put]

Could you maybe shoot a 5 to 10 second clip which shows the flickering you are talking about and then make that file available for download (the clip straight from the camera card without any conversion) so some of us could have a look? I use Edius 7 as well so we might be able to compare settings to see what is causing the issue.

[Adriano Moroni]

Ok, these are my clips:
the first one is Original 4K clip and the second one is an Exported HD clip with flickering.
https://dl.dropboxusercontent.com/u/...04K%20clip.MP4
https://dl.dropboxusercontent.com/u/...flickering.mp4
I have many clips with flickering. If you watch it with the monitor of the PC you will see a good clip. You should watch it on a big TV with external player.

[Vaughan Wood]

I shot I a walk around here (Aspendale, Melbourne, AU) yesterday in 4K at 25fps and 50 shutter speed and Edius showed it all as a series of flickers on grass, trees etc, (even in a 4K project), so I am very interested in this thread. Unfortunately I am going away for a few days and can't test further until later next week, but I will shoot some more of the "scenery' at Surfers Paradise while I'm away to test with!

Vaughan

[Alister Chapman]

When I watch Adriano's clips on my Retina laptop display or a 4K monitor I do not see any flickering in the original clip, but on the HD clip I do see some very minor aliasing issues on the middle distance trees on the right hand side of the image and some compression blocking on the upper left of the image (probably due to aliasing in the conversion process).

I don't really see any particularly bad or noticeable flicker, certainly nothing that jumps out at me.

Points to consider are:

When down converting from UHD to HD (including viewing footage on an HD display when editing a 4K project) you do need to use a scaling process that will perform good quality pixel blending, image re-sampling or another form of anti-aliasing. A straight re-size will result in aliasing which can appear as either flicker, moire or a combination of both.

After re-sizing the image will be incredibly sharp compared to what most HD cameras or HD broadcast deliver. In particular it will have very high contrast in the finest of details. A conventional HD camera will not (or at least should not) have this due to the cameras HD Low Pass Filter which reduces contrast in fine details to prevent flicker and aliasing.

TV sets add detail correction and sharpening to compensate for this and to make the pictures look sharper. Computer monitors typically do not.

Feed a super sharp, high contrast image to a TV and it will enhance and further sharpen the already super sharp image. This can often lead to flicker, jagged edges, flashing highlights and other nasty looking side effects, especially if the down converted footage has not be anti-aliased.

Things to try: Find a better scaling process for your down conversion that includes anti-aliasing. Turn down or turn off the image sharpening on the TV.

We had all of these same "issues" when people used HD cameras to shoot SD and didn't have HD TV's. Many blamed the cameras when really the problem lay elsewhere.

[Don Meers]

Originally Posted by Vaughan Wood

Yippee!

I got mine yesterday! Must be the first "E" model in Australia I think, as I ordered from the 1st website that put it up.
Ordered on Thursday, delivered from Hong Kong Monday morning!

Sony Australia still have "coming soon" on their website, and are talking late June "they may have some news". Hopeless I think!

Cheers,

Vaughan

Hey Vaughan which website did you purchase through? I was thinking of buying from China but was a little suspect.

[Adriano Moroni]

Originally Posted by Alister Chapman

Things to try: Find a better scaling process for your down conversion that includes anti-aliasing. Turn down or turn off the image sharpening on the TV.

I use Edius 7 for video editing. On the timeline I put 4K clips and the Edius preset is:
https://dl.dropboxusercontent.com/u/...ttings%202.jpg
I think Edius is configured fine.
I like to tell you my TV works very fine with another camera Sony AX2000 (HD files). I've ever had seen that flickering problem. I can assure you that it is very obvious even after lowering the sharpening of the image on TV options.
How can I solve my workflow? Some help please?
If I cannot solve my flickering problems I will have to sell my AX100. What a pity!

[Alister Chapman]

Adriano, I checked your clips and there is really very little wrong with them. You have said yourself that the footage looks fine on a computer monitor, so there is probably nothing wrong with the footage or the camera. If the footage itself contained the flicker you would see this on every monitor. The fact that you only see the issue on your TV points to the TV being a significant part of the issue.

The AX100's internal UHD to HD down scale includes an anti-aliase filter.

I'm sorry but I don't use Edius so I cant recommend a specific workflow for Edius. But normally you should be working in a 4K project and 4K timeline and doing the down scale at the end rather than working with the 4K clips in an HD timeline. Simply dropping 4K clips into an HD timeline is often far from ideal.

[Ken Ross]

Originally Posted by Adriano Moroni

If I understand fine, the best way is that I have to add a slight blur to those flickering clips on the timeline. As I have many of flickering clips I'd like to know if even you get some flickering clips.

Edit: I am very worried. I did some tests with both the filter, blur and ati-flicker. Hard blur filter and Anti-flicker 100% filter, both filters improve very slightly the flickering but they don't eliminate it at all. And after it the image deteriorates a lot.

Did you try playing the camera's footage directly to your TV as a couple of us have suggested? This is without question your starting point. If you don't see a virtually perfect down-scaled 1080p image that way, then something else is wrong.

If your image is fine from the camera to the TV, then you can move on to your editing system.

As we have mentioned, the fault is not with the camera.

[Adriano Moroni]

Originally Posted by Ken Ross

Did you try playing the camera's footage directly to your TV as a couple of us have suggested?

I'm waiting for the sun to make this test. Flickering shows with sun only. I have formatted my SD and I cannot do it. May be can I import those original 4K files from hard drive into the SD again?

[Claire Watson]

My guess is it's a monitoring issue, I see serious line twitter watching Adriano's mp4's on my Panasonic editing HDTV (not 4K).

This is while playing from Edius 7 timeline via HDMI from my GV Storm 3G hardware. Unfortunately this HDTV like many others does not have an actual 25P mode, it's only 50i, primarily for broadcast transmissions. Of course the preview on my computer screen doesn't show line twitter since most computer displays are 30P progressive but my HDTV has to deinterlace causing the line twitter on the sharp detail in the video I see here.

To prove this I placed both mp4 files in an Edius 23.98p project.

My BM decklink card comes in handy here, since it does true progressive 23.98 output and my HDTV does have this mode so no deinterlacing is attempted. I conformed the clips in the bin from 25p to 23.98 and dropped them on the timeline, sure enough they then previewed just fine on my HDTV.

I am used to this issue since for a while I have filmed with an EX1R in 25P but due to this line twitter while monitoring have switched to 24p and now 50P on latest cameras.

Of course a 4K tv will surely have a true 25p mode? I do hope so!

[Piotr Wozniacki]

Originally Posted by Adriano Moroni

I
How can I solve my workflow? Some help please?
If I cannot solve my flickering problems I will have to sell my AX100. What a pity!

Just apply an extremely small amount of vertical Gaussian blur before rendering to HD. I do it all the time when rendering my HD source for DVD delivery; I use Vegas Pro and some 0.001 is just enough (to give an idea of what I mean by "extremely small amount" :-))

[Adriano Moroni]

Originally Posted by Piotr Wozniacki

Just apply an extremely small amount of vertical Gaussian blur before rendering to HD. I do it all the time when rendering my HD source for DVD delivery; I use Vegas Pro and some 0.001 is just enough (to give an idea of what I mean by "extremely small amount" :-))

I have just used an hard blur but I get the same problem. I am angry because I bought a 4K camera and I can use it recording in HD only.