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Posted by Smarty on 11/03/07 19:28
Paul,
I just read your Saturday afternoon update on the DVI forum, and am very
pleased to learn that readjusting the TV set sharpening apparently solved
the problem.
Today's overcast weather in the L.A. area may prevent seeing the HV-20 at
its' best, but I am anxious to see / hear how the experimentation and
comparisons went. I meant it most sincerely when I said my 3-CCD FX-1 could
not compare to the HV-20, to such an extent that I literally put the FX-1 on
craigslist.com and sold it once I saw how well the HV-20 performs. Same
thing with the HC-5. Others have made similar comments and reports.
What are your present thoughts?
Smarty
"PTravel" <ptravel@travelersvideo.com> wrote in message
news:5p12idFof3pjU1@mid.individual.net...
>
> "Spex" <No.spam@ta.com> wrote in message
> news:13imfvhg31fbe63@corp.supernews.com...
>> There doesn't look much wrong with this screen grab. There is a
>> considerable amount of sharpening that will catch the eye as the video
>> moves. With so much native resolution there is little value keeping the
>> sharpening that high.
>
> Yep -- that's exactly what I'm seeing. I'm pleased with the resolution
> and color fidelity of the image, but "shimmering" on movement is driving
> me crazy.
>
>>
>> PTravel, why not post a RAW m2t clip to Rapidshare??? It won't cost you
>> anything.
>
> I'll try that this weekend.
>
>>
>> How hot are the whites in the image? Check their level.
>
> I'll look this weekend.
>
>>
>>
>> Smarty wrote:
>>> For whatever it is worth, the frame grab looks to my (60+ year old) eyes
>>> as being pretty typical of what I would expect for the HV20 with
>>> additional JPEG processing applied. If I look at the very finest detail
>>> in the picture, such things as the parking meter next to the car, small
>>> signage detail on the lamp-post as well as the very tip of the lamppost,
>>> variegations in the fencepost masonry, and other really small (just a
>>> few pixel wide / tall) elements, my impression is that the capture has
>>> both preserved the edge definition without fringing (unlike the cheaper
>>> Sonys which make artificial edge sharpness by deliberate overshoot) and
>>> that there are no clear examples of a defect. The areas you enlarged do
>>> look a lot different from the very same areas which I enlarge using
>>> Photoshop, and thus your surrounding magnified crops do look distorted
>>> but only when I look at your magnified crops, and not when I look at the
>>> same high magnification of these areas using the central 1440 by 1080
>>> image. I am not sure what to make of all of this.
>>>
>>> None of these comments / observations apply, of course, to what you are
>>> seeing on your TV set, or what the moving, dynamic video looks like
>>> versus this single static frame. All I am saying is that the sensor and
>>> encoder appear to be doing their job for this image without losing the
>>> fine detail, and that the detail which is preserved does not (to my
>>> eyes) appear to have distorted or exaggerated edges, color issues, or
>>> other evidence of a defective sensor, encoder, or optics.
>>>
>>> You alone can judge how faithfully this HV20 is capturing the true
>>> scene, and in this regard, another still camera with high resolution
>>> might allow you to make some further comparisons. I will often use my 8
>>> MPixel Nikon to take comparison shots for seeing where the video camera
>>> is weak. Obviously the color gamut and resolution is worse in the video
>>> sample, but the comparison to a reference can help discern the video
>>> shortfalls easier.
>>>
>>> It will be interesting to see if any of my observations agree with
>>> anybody else's. I am not an expert at all in these matters, and have
>>> cataracts to further confuse the issue, so I am merely offering my 2
>>> cents worth in a sincere effort to be helpful.
>>>
>>> I'm glad to keep working this to get more insight into what you are
>>> encountering.
>>>
>>> Smarty
>>>
>>>
>>> <ptravel@travelersvideo.com> wrote in message
>>> news:1193986489.385033.199060@q3g2000prf.googlegroups.com...
>>>> On Nov 1, 7:51 pm, "Smarty" <nob...@nobody.com> wrote:
>>>>> Paul,
>>>>>
>>>>> I have not seen the problem you describe, but it may be the fact that
>>>>> I
>>>>> virtually never view the camera through its' HDMI port. I normally
>>>>> capture
>>>>> the Firewire data / .m2t, edit and author an HD DVD, and watch the
>>>>> resulting
>>>>> (non-transcoded) output. When I have made direct comparisons from tape
>>>>> output from the camera's HDMI port versus playback of the HD DVD via
>>>>> HDMI,
>>>>> both had none of the "shimmer" you describe at the post on the DVI
>>>>> forum you
>>>>> linked to.
>>>>>
>>>>> I think the distinction you make regarding dramatic differences in
>>>>> HDMI
>>>>> versus component is very telling, however. Both should contain high
>>>>> frequency components up to about the same cut-off frequency /
>>>>> half-power
>>>>> point. Each delivers essentially the same bandwidth and resolution.
>>>>> And on
>>>>> the 2 HDTV monitors I have here (both of which are 1080p) as well as
>>>>> the
>>>>> computers / monitors I have for editing, the progressive display shows
>>>>> no
>>>>> such effects. Perhaps the camera's 1080 interlaced signal is managed
>>>>> differently on your monitor when seen through the HDMI port versus the
>>>>> component input? I personally doubt the default setting of the
>>>>> camera's
>>>>> sharpening would (if the camera is working properly) create this
>>>>> effect,
>>>>> although reducing the high frequency energy with lower sharpening may
>>>>> "solve" the problem at the expense of the camera's excellent
>>>>> resolution. If
>>>>> it were me, I would want to see another HDTV / monitor with HDMI to
>>>>> judge
>>>>> how much of this, if any, is truly a camera issue. If it persisted in
>>>>> the
>>>>> second monitor, I would get a replacement camera.
>>>>>
>>>>> The mpeg encoder is imperfect, and motion does stress the encoder so
>>>>> as to
>>>>> make fast pans take on a more under-sampled and degraded appearance,
>>>>> but
>>>>> very very seldom have I seen any real macroblock effects or other
>>>>> artifacting. My movies of Niagara Falls, with lots of vertical water
>>>>> motion,
>>>>> horizontal panning, and very agitated and tiny water details is about
>>>>> the
>>>>> most stressing case I have tried, and even then the HV-20 was a vast
>>>>> improvement over the older FX-1 as well as the recent Sony HC-3 my son
>>>>> was
>>>>> using.
>>>>>
>>>>> Although I am by no means an advocate of high priced cables, I might
>>>>> also
>>>>> take a look at the HDMI cable being used between the HV-20 and the
>>>>> HDTV. The
>>>>> cables I use here are very inexpensive, work very well, and introduce
>>>>> no
>>>>> particular problems, but it is remotely possible that high frequency
>>>>> ringing
>>>>> or other transient / overshoot problems could make the HDMI port look
>>>>> bad.
>>>>> This is a bit far fetched but worth a quick substitution if you have
>>>>> another
>>>>> HDMI cable to substitute.
>>>>>
>>>>> Please continue to update as I really would hope this problem is not a
>>>>> deal-breaker.
>>>>>
>>>>> Smarty
>>>> Smarty, thanks for the response. I've got a bunch of HDMI cables here
>>>> but, as it happens, the one I was using is the best I have -- though
>>>> money isn't necessarily a measure of quality, this one cost me $70.
>>>> I'll try a couple of others this weekend.
>>>>
>>>> I took a look at a frame grab. To my eye, there are sharpening
>>>> artifacts or, at least, some kind of high-frequency distortion. I
>>>> posted it here:
>>>>
>>>> www.travelersvideo.com/hv20.jpg
>>>>
>>>> In the interest of bandwidth, I had to compress it rather heavily, but
>>>> I think the artifacts show through. I REALLY want to like this
>>>> camera, so I'm going to do some more extensive tests this weekend,
>>>> including lowering sharpening and trying it in 24p mode (though my
>>>> preference is to shoot 1080i/60).
>>>>
>>>>> "PTravel" <ptra...@travelersvideo.com> wrote in message
>>>>>
>>>>> news:5oue5kFoaqqtU1@mid.individual.net...
>>>>>
>>>>>
>>>>>
>>>>>> "Smarty" <nob...@nobody.com> wrote in message
>>>>>> news:J9aWi.29875$eD3.26430@trnddc03...
>>>>>>> Looks like nappy is beginning to get tempted...... I am anxious to
>>>>>>> see
>>>>>>> how you and the other true professionals here find this camera,
>>>>>>> since I
>>>>>>> judge image quality and other related performance mostly as a
>>>>>>> non-professional user.
>>>>>> As everyone here knows, I am far from a professional, either in
>>>>>> skill,
>>>>>> experience or knowledge. However, I've hit a significant problem
>>>>>> with the
>>>>>> HV20 that may result in my returning it.
>>>>>> Short version: there are significant motion artifacts in
>>>>>> high-frequency
>>>>>> detail, not unlike what you see with a Bayer-filtered single-CCD SD
>>>>>> camcorder. The problem is dramatic on the camera's HDMI output, far
>>>>>> less
>>>>>> visible on component out. I'm still trying to figure out whether it's
>>>>>> caused by over-sharpening in the camera, lousy HDMI circuitry, or
>>>>>> something odd with my television.
>>>>>> I've discussed it at length here:
>>>>>> http://www.dvinfo.net/conf/showthread.php?p=768436
>>>>>> Since these videos are for my own personal use only, I may keep the
>>>>>> camera
>>>>>> as long as it looks good on the component output. However, I'm going
>>>>>> to
>>>>>> do so more tests this weekend. If the output continues to display
>>>>>> these
>>>>>> signficant high-frequency motion artifacts, I'm returning it and
>>>>>> waiting
>>>>>> until next year to buy either an AH1 or FX7.
>>>>>> I'm really disappointed -- I had high hopes for this machine.
>>>>
>>>
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