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-   Sony HVR-Z1 / HDR-FX1 (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/)
-   -   Any reviews with hard facts? (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/36570-any-reviews-hard-facts.html)

Chris Hurd December 18th, 2004 09:33 PM

<< If I could post images in-line in a thread here I'd do so, but there are so many pictures that it would be awkward to constantly refer someone out of the thread to a picture and then back >>

Actually Barry if you wanted to share some of those images, I could put 'em on a page (or pages) on the content side of this site (at www.dvinfo.net/articles, which would open in a separate window -- no need to send someone out of a thread. Just wanted to make that option available to you.

David Newman December 18th, 2004 10:00 PM

Barry,

Therefore sounds like a scaler issue as the HDV will have more chroma detail and equal luma detail. There are many factors to consider when doing the scale. Are you doing an interlace mode scale (even if you shoot 30p?) This will greatly limit for scaling quality. Also are we talking real detail or sharpness? The DV sources are slightly sharpened, whereas the post sharping is lost when you down-scale. You may need to apply an unsharpen mask to your scaled footage to match the processing path that the SD footage went thru in camera.

Heath McKnight December 18th, 2004 10:56 PM

35mm downcoverted to DV still looks better than DV, so I can safely assume HDV converted to DV will look great and noticable vs. native DV.

heath

Barry Green December 19th, 2004 12:47 AM

Quote:

Therefore sounds like a scaler issue as the HDV will have more chroma detail and equal luma detail. There are many factors to consider when doing the scale. Are you doing an interlace mode scale (even if you shoot 30p?)
You can't shoot 30p on the FX1, as of course the camera is only capable of 60i. I've downrezzed CF24, CF30 and 60i modes.

Quote:

Also are we talking real detail or sharpness? The DV sources are slightly sharpened, whereas the post sharping is lost when you down-scale.
I'm talking about observing the footage of the three cameras simultaneously, and seeing the FX1 footage looking "soft". All three cameras were set to mid detail level (the Sony defaults to +12, I set it down to 8 which is the middle...)

Quote:

You may need to apply an unsharpen mask to your scaled footage to match the processing path that the SD footage went thru in camera.
I'm going to have to take Chris up on his offer to host pictures. I went through some convoluted exercises to get to the bottom of it, and have some pictures to show why. Bottom line is, downrezzed FX1 does look a little bit softer than straight DVX and XL2. I've heard people proclaiming that it looks so much better, but I've been unable to find any sort of supporting evidence to back that up. I understand the theories of why it is supposed to be, and I know that people want it to be, but I'm not really all that concerned about what "should be", only what *is*. I'll gather the pics and stuff and have Chris put up an article, and then you guys can go through and see what I'm seeing, and if there's something I'm doing wrong, let's hear it.

Barry Green December 19th, 2004 12:51 AM

Quote:

35mm downcoverted to DV still looks better than DV
Ah, but Heath, you know what they say about assuming, of course. 35mm to DV is such a completely different animal from downrezzing a digital HD source, that it's entirely not possible to compare them. 35mm is scanned by an optical CCD, whereas HDV is a digital image that's being digitally resized. Completely, thoroughly, totally different animal.

If you want to explore the 35mm analogy, the only way to make it apply would be to say: would 35mm telecine'd to HDV and then downrezzed to DVD look better than 35mm telecine'd to standard-def and then put on DVD? And the answer, I strongly suspect, is no.

Quote:

so I can safely assume HDV converted to DV will look great and noticable vs. native DV
I know exactly why you said what you said, and it does seem like a safe assumption, but that's why I run tests: to find out what *is*, rather than just accept what's *supposed to be* because frequently they are not the same thing. It does look good, it looks almost the same (resolution-wise) as native DV from the XL2 and DVX. But not better. People have gone so far as to say that downrezzed FX1 footage "blows away" these other cameras on DVD. I'm saying that's completely false, and downrezzed FX1 looks *almost* as good as the other cameras. But not better.

Harish Kumar December 19th, 2004 07:25 AM

so Barry, that would mean if my film is to be DVD release then I am better off stick with DVX100a and dont sell it to replace FX1/Z1 ...as I am sure it will be a DVD release as the previous one shot on DVX . Is that safe to assume at this moment....sorry not assume but from the tests you have conducted?


Thanks

Toke Lahti December 19th, 2004 07:49 AM

<<<-- Originally posted by David Newman : Barry, Therefore sounds like a scaler issue as the HDV will have more chroma detail and equal luma detail. -->>>

Could it be mpeg2 that blurs the picture?
There's usuallly some amount of macroblock's edge blurring and details are lost within macroblocks due to DCT.

Ron Evans December 19th, 2004 07:52 AM

Barry did you also do the tests with FX1 at its default of +12 since this is the way it will be used most of the time on PP1, with no PP set to off ( what ever that does to the settings!!) and at DV to see if there was a real difference. Have you also used the Cineform wavelet intermediate as a transfer to DVD?

Ron Evans

Heath McKnight December 19th, 2004 08:57 AM

Barry,

My HD10 shot in HD mode and down-converted to DV looked better than when I shot on DV mode.

heath

Mike Tiffee December 19th, 2004 09:01 AM

<<<-- Originally posted by Ron Evans : Barry did you also do the tests with FX1 at its default of +12 since this is the way it will be used most of the time on PP1, with no PP set to off ( what ever that does to the settings!!) and at DV to see if there was a real difference.
Ron Evans -->>>

I too wonder that - why cripple the camera then complain about it's relative lack of sharpness?

Also- another thing to consider- the HDV footage will hold up much better during multiple render passes, effects, etc. Any artifacts introduced whill be hidden during the HDV > DVD down res. While the artifacts on the SD footage will remain. I still find it hard to believe the FX-1 footage doesn't look as good- I've done a good bit of screen grabs and when I resize the images from HDV resolution to DV resolution, the resulting images are always much crisper than a DV screengrab. Now I realize I'm comparing the FX-1 to the FX-1 but the difference in images is HUGE.

I'm curious to hear your exact workflow, including settings, etc.

- I'm also curious to compare the HDV 4:3 center cut output of the Z1 vs the same footage in DV.

Also- the FX-1 default is +11 not +12.

Anhar Miah December 19th, 2004 10:26 AM

Video files
 
Barry could you post both raw DV (from DVX100/a) and FX1 m2t files of the same scene (about 5 seconds or whatever suits you), i would like to test the downres for my self thanks Barry!

David Newman December 19th, 2004 11:57 AM

I agree, source files would be handy as the scaling can be done to achieve the desired results.

Barry,
Film telecined (or scanned) to HD (or 2k -- 10% more than HD) then down res'd to SD also looks great. It is a standard industry workflow. In a digital intermiate workflow, color correction is often done on 1k proxy files (around 960x540), for film out the 2k (or greater) is processed, but for the DVD these 1k proxies of often used (are looks perfect.) Oversampling works, all that signal processing theory can't be wrong -- only implementations can be.

Barry Green December 19th, 2004 12:42 PM

Quote:

that would mean if my film is to be DVD release then I am better off stick with DVX100a and dont sell it to replace FX1/Z1 ...as I am sure it will be a DVD release as the previous one shot on DVX . Is that safe to assume at this moment....sorry not assume but from the tests you have conducted?
What I'm saying is, for DVD release, the FX1 offers no advantage over the other cameras. So you wouldn't want to replace a DVX with an FX1 just to get a better-looking DVD, because it won't look better. In interlaced mode it'll look about the same, maybe a tiny bit softer, but the DVX will give you two stops more sensitivity, 24P, more picture control, more manual control, better audio, etc.

The FX1's advantage (and it is a big advantage) is for HD content creation. But if you're not releasing on HD, that advantage is nullified, so you're left comparing the cameras at SD resolution. And in any direct comparison between them at SD, the FX1 doesn't do as well as the XL2 or DVX. (except when it comes to picture noise, where the FX1 is quite a bit cleaner than the DVX in the shadows).

Barry Green December 19th, 2004 12:43 PM

Quote:

Could it be mpeg2 that blurs the picture?
There's usuallly some amount of macroblock's edge blurring and details are lost within macroblocks due to DCT.
Certainly it does. However, keep in mind that I'm comparing all three cameras split-screened into the same frame, so any MPEG artifacting/blurring would be applied to all three images equally.

Barry Green December 19th, 2004 12:45 PM

Quote:

Barry did you also do the tests with FX1 at its default of +12 since this is the way it will be used most of the time
I did not. I tried to neutralize the effect of the various settings. I mean, we could have also tested with the DVX at +7 and the FX1 at +15, and the DVX at -7 and the FX1 at 0, and every combination in between, but there's only so much time in the day and so many ways you can test something. So I set 'em at neutral (or what I expect would be neutral).

Quote:

Have you also used the Cineform wavelet intermediate as a transfer to DVD?
Did not use the Cineform, I wanted to go from the original source as that would be the highest-quality and most accurate way to go.


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