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-   Sony HVR-V1 / HDR-FX7 (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/)
-   -   25P Fix....ed. (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/83033-25p-fix-ed.html)

Tony Tremble January 3rd, 2007 09:18 AM

25P Fix....ed.
 
Hi All

Just received my V1E back from Sony....Well......

Now I can't see any difference between 25P and 50i. I think we can safely say the "oil paint" effect can now be banished to history. :)

I cannot see any signs of crawling edges or over sharpening. There is a very slight difference between 25P and 50i images, 25P being everso slightly sharper. This could simply be due to different line up of photosites or different chroma-sampling between clips. I am splitting hairs to be honest.

I'll get the camera out tomorrow and get some shots to upload. It's very dark and drizzling with rain here so no shooting outside today.

Cheers

TT

Piotr Wozniacki January 3rd, 2007 10:29 AM

Tony, good to hear it's been fixed, and looking forward to some more comments.

My camera was collected on the 28th of December, so I don't think it'll be back before next week.

Steve Mullen January 3rd, 2007 03:32 PM

Quote:

Originally Posted by Tony Tremble
There is a very slight difference between 25P and 50i images, 25P being everso slightly sharper.

GREAT NEWS!

What Sharpness level are you using?

Could you try 5 7 9 to see if the Sharpness differentially affects I vs P?

At 5 most everyone thought my 24P was softer than 60i.

But at 7 30P was seen to be equal to 60i.

Tom Roper January 3rd, 2007 08:45 PM

If someone will post of video grab(s) of an ISO 12233 or slant edge chart, I'll be happy to evaluate the sharpening, or the difference in sharpening between 24P,30P and 60i, or between different sharpness settings using the Imatest MTF50 spatial frequency test. At any given setting of sharpness, it will state the percent over/undersharpened relative to a standard 2 pixel radius. Another useful result would determine which in-cam sharpness setting equates to zero over/under sharpening.

Michael Phillips January 4th, 2007 01:13 AM

Quote;
"Now I can't see any difference between 25P and 50i. I think we can safely say the "oil paint" effect can now be banished to history. :)"

With the monitors and other viewing devices, what setups or devices do we need to correctly view the difference between 25P and 50i that the V1-P produces.
Michael.

Tony Tremble January 4th, 2007 01:52 AM

You need at least a 1920x1080 capable monitor. The very slight differences in sharpness between 25P and 50i would be lost on anything less. The difference would be impossible to see at a typical living room viewing distance even on a massive screen.

We are talking tiny differences that might not even be down to the camera but rather the NLE's handling of 25Psf.

TT

Tony Tremble January 4th, 2007 02:20 AM

Quote:

Originally Posted by Steve Mullen
GREAT NEWS!

What Sharpness level are you using?

Could you try 5 7 9 to see if the Sharpness differentially affects I vs P?

At 5 most everyone thought my 24P was softer than 60i.

But at 7 30P was seen to be equal to 60i.

Cheers Steve.

The sharpness was set to 3 for both I and P for my quick test.

I saw the extra sharpness in your P grabs as well. It's something I am hugely worried by as it is barely visible. :) Because of the oil paint effect I've scrutinised the image far more than really necessary.

TT

Piotr Wozniacki January 4th, 2007 07:38 AM

Tony, I take it that (apart from 25p being "everso slightly sharper") you don't confirm the crawling ants artefacts as a side-effect of the oli-paint/softness cure. Is that right?

Ken Ross January 4th, 2007 10:19 AM

Glad to hear all is well now Tony!

Tony Tremble January 4th, 2007 11:12 AM

Stairstepping!!!!.
 
1 Attachment(s)
Quote:

Originally Posted by Ken Ross
Glad to hear all is well now Tony!

Cheers Ken!

Might have spoken too soon!

For those that are interested check out the grab. Take a close look at the right hand swan and the stalks of grass in front of it. There is some stairstepping of those blades of grass.

The camera was left with the default sharpness of 7 (see the halo round the Swan this is why I prefer much lower. you really only notice the steps when close to the screen but from a viewing distance the image looks "very HD." Unbelievably sharp, almost too sharp for my eyes!

Unfortunately I don't have any more progressive footage shot with a lower sharpness setting.

I did a quick export to 1280x720P and the stair steps are no longer visible.

Question for those that know more about the HDV format than me,

Is this a limitation of the format that is showing up in this grab? perhaps the dreaded 4:2:0. But why are these jaggies not seen in 50i?

Am I worrying too much? At a normal viewing distance the jaggies are not visible and the image looks crisply sharp.

Anyone like to comment?

TT

If a TV made an utter hash of de-interlacing 25Psf (25P in 50i) then I could see these jaggies being quite visible.

Ing Poh Hii January 4th, 2007 11:40 AM

Hi Tony, it is nice to see you got everything just as expected, this image does look good apart from the strange "interlacing effect" spotted by you (oh my god, you really look into so much detail), I wonder it is because the glass is too thin and waving in front of white subject, will this make too much challenge for HDV encoding ?

Or is it caused by the rolling shutter recently mentioned by other thread ? I trust you didn't go with high speed shutter.

Or perhaps the high sharpness setting has splited the thin glass into pieces (so avoid default sharpness setting).

Or the 45 degree CMOS has done anything to this ?

I am sure you can do more test in coming days. But this oil-free image does put Sony back to the track :D.

Kristin Stewart January 4th, 2007 11:53 AM

Strange, Tony. There seems to be a lack of details in the overall image, but that's probably because I just checked out some Red frames... These "steps" you're talking about look a little bit "interlaced", but that's probably me. Have you checked the way you capture ? Do US users have this problem with 24P ?

Thanks for this frame grab, looking forward to discovering 25P footage !

Kristin

Ken Ross January 4th, 2007 12:41 PM

Tony, how obvious is the stairstepping on moving video? I don't trust frame grabs as they tend to introduce many artifacts not visible in the moving video.

I agree with you about the default "7" sharpness. It is exceedingly sharp, but can introduce those halos around certain objects. Many times, depending upon the scene, you won't see it at all, but at other times it's there. But I have to admit I love that super-sharp look....it's kind of what HD is all about. I may try a setting of '5' and see how that looks, but I seem to recall that I could still see some halos around wires against a sky when I was experimenting with my FX7 @ a setting of 5.

Ray Bell January 4th, 2007 01:06 PM

Hey Tony, I could be wrong here and only one way to see for sure but
the grass that you describe could actually be the seed stalks for that
particular grass type... the blade that runs across the neck for sure looks
at first to be stair'd but again, to me it looks like a seed stalk...

You'd have to go out into the marsh and look at the grass, but it is that time
of year for grass to seed ... :-)

If indeed those are seed stalks then I'd say your cam is doing a fantastic job of detail.. :-)

The seed stalk I'm talking about is not a grass blade, but a long straw that
comes out around the grass into the air and it has the seeds on the stalk.

Tony Tremble January 4th, 2007 02:50 PM

Quote:

Originally Posted by Ray Bell
Hey Tony, I could be wrong here and only one way to see for sure but
the grass that you describe could actually be the seed stalks for that
particular grass type... the blade that runs across the neck for sure looks
at first to be stair'd but again, to me it looks like a seed stalk...

You'd have to go out into the marsh and look at the grass, but it is that time
of year for grass to seed ... :-)

If indeed those are seed stalks then I'd say your cam is doing a fantastic job of detail.. :-)

The seed stalk I'm talking about is not a grass blade, but a long straw that
comes out around the grass into the air and it has the seeds on the stalk.

Unfortunately it isn't seeds. I have a close up and they are just blades of grass.

I wonder if 24P users notice any artefacts like this?

50i looks much better in my opinion. All the fine detail has lovely anti-aliased edges in 50i.

Anyone got any ideas?

Cheers

TT


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