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-   -   VX2100 Still Pictures on DVD Photo Disks (https://www.dvinfo.net/forum/sony-vx2100-pd170-pdx10-companion/75704-vx2100-still-pictures-dvd-photo-disks.html)

J. Stephen McDonald September 17th, 2006 11:22 PM

VX2100 Still Pictures on DVD Photo Disks
 
Here's a summary of what I discovered about the practical aspects of various levels of picture resolution, when they are viewed using common display media:

I captured a large number of 640 X 480 memory mode pictures on a MemoryStick, in my VX2100. I also took some 1600 X 1200 (2 MegaPixel) photos with a digital camera. I mixed them together on a DVD photo slideshow, put together with a photo software program. By the time the photos got onto my HDTV (in SD display mode), the higher resolution pictures were dumbed-down to the point that they were indistinguishable from the 640 X 480 ones. However, they all still looked pretty good, compared to most standard-definition video images. The DVD recorder I used to play the photo-DVD onto the HDTV, has component connectors (it also has an HDMI output that gives identical results with SD programs). The end results, as they would be if I distributed copies of my various photos on DVDs, have given me a new sense of appreciation for the usefulness of my VX2100's still-picture function.

On a somewhat related note, since my computer screen maxes-out at a 1600 X 1200 resolution, my recent thoughts about buying a 7-MegaPixel still camera, have been tempered a bit.

Even further removed, is the issue of using my "high-grade" Sony telextender, the VCL-HG1758, that I bought for the VX2100, with this proposed 7MP still-camera. Since the pixels on this 7MP camera's CCD are only 1/13th the size of those on the VX2100, what are the chances its optical resolution would be enough to avoid degrading the 7MP image? Sony recommends another of its telextenders, the VCL-DH1758, for use on this camera (The DSC-H5). The VCL-DH1758's street price is only about 1/3 of what I paid for the VCL-HG1758, so I'm wondering how they could give it enough extra optical resolution to do the job, for such a small amount of money? I've sent an E-Mail to Sony posing these questions and asked them for the resolution specifications for their various telex lenses. I'm sure they will reply promptly, with all the documentation I've requested.

Follow-up one day later: I was partly right----Sony promptly sent me a reply, but it was a non-answer. They told me to contact Sony Parts if I wanted to buy accessories, but mentioned nothing about lenses or their specifications. They thanked me for my interest in Sony products and said they hoped their response was helpful.

Eric Stemen September 18th, 2006 04:54 PM

have you tried putting your'e vx in progressive mode and doing frame captures instead of memory?

J. Stephen McDonald September 18th, 2006 07:02 PM

Quote:

Originally Posted by Eric Stemen
have you tried putting your'e vx in progressive mode and doing frame captures instead of memory?

Yes, I have. And in some cases with moving subjects, this is the best way to grab that one special frame that you want. You get 15 or 12.5 FPS from tape footage, and hundreds (or thousands) from which to choose, compared to just a single shot at a time in memory mode. However, this uses up tape and the low frame-rate of this model's progressive video mode produces footage that is unusable for anything but frame-captures. Also, the very fast and effective mechanical shutter operates only in memory mode. The camera automatically shifts to progressive scan during memory shots, so you have both that and the mechanical shutter to improve the images.

By comparing still pictures from these two different modes, in most cases I found the memory shots to be superior, with the exception of fast-moving subjects, which are hard to catch with a single snapshot. You do generally need better light to use memory mode, as the mechanical shutter can't be adjusted in the way that you can slow the electronic shutter for low light in video mode. In dim light, further opening of the aperture can't offset all the limiting effects of a fast shutter.

If you're shooting video in progressive mode, for later still-capturing, you should use a higher shutter speed for moving subjects, especially flying birds, to minimize blurring. Even with progressive video scan, there can be a bit of blurring with very fast subjects, if a too-slow shutter is used.

However, if you're shooting regular, 30 or 50 FPS interlaced video footage, I advise using only the normal shutter speed (1/60 or 1/50), for some types of fast-moving subjects. This includes not using the AE Sports Mode. When flying birds are shot using a fast shutter, flickering of their wing images occurs. It makes it appear that their wings are in several positions at once. This is because when a fast shutter opens 60 or 50 times per second, there's a strobing-type effect. This is due to the way these isolated wing positions appear in each video field and are perceived by your visual process. With normal shutter speed, the wings blur on video, in the same way your visual system naturally sees them in life. Test this out on birds and see if I'm not right.

If you shoot moving subjects in interlaced video mode with a fast shutter, thinking that it may improve still-captures you may make later, you might be compromising the quality of the real-time video.

Of course, there are times when a faster shutter can be used to control exposure or the depth-of-field in focusing. Perhaps a higher shutter speed might be used for auto racing or similar subjects, that don't have wings or legs that move rapidly back and forth.

Eric Stemen September 18th, 2006 10:20 PM

I completly agree with you about the not using high shutter speed on fast moving objects. The blur is pretty much nessasary shooting interlaced. I forgot the vx uses a mechanical shutter for still capture.

J. Stephen McDonald September 19th, 2006 06:52 PM

Quote:

Originally Posted by Eric Stemen
I completly agree with you about the not using high shutter speed on fast moving objects. The blur is pretty much nessasary shooting interlaced. I forgot the vx uses a mechanical shutter for still capture.

But the fact remains, that the camcorder manufacturers provide a "Sports Mode" in their AE-program options, that uses a high shutter speed. Their standard advice is that the higher shutter speed improves the quality of moving subjects. For moving subjects in general, this is poor advice, in my opinion. Only if you want to do nothing except make still captures later from interlaced footage, should a fast shutter be used for most moving subjects. And since the main purpose of video recordings is to show them in real-time, it makes me wonder why they keep giving out this misleading instruction. They call 1/60th of a second (1/50th for PAL) "normal shutter", because it allows for video images to most closely resemble the way our eyes naturally see things.

I once was talking to a camcorder jock from a local TV news crew and he said that all their BetaCams had been set-up so nothing but the normal 1/60-sec. shutter could be used. This was to keep them from accidently setting them at a fast shutter speed for sports coverage and causing fast-moving legs to show strobing or flickering.


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