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Old Nov 1, 2005, 3:53 PM   #1
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I recently put together a DVD slideshow using several hundred 3-megapixel (2048x1536) photos from a recent vacation. The photos look terrific under normal conditions (i.e. when printed or when viewed on my computer monitor), but when viewed as a "DVD slideshow" on a TV set they look absolutely awful. I was shocked at the huge reduction in image quality. They shouldn't even call this feature a "slideshow", as the mangled images don't come anywhere near the superb display quality of an old-fashioned slide projector.

In an attempt to understand and possibly solve the problem I ran a number of tests. I used several different image assembly methods and displayed my photos on several different TVs (including large widescreen models), as described below:

1) I plugged the camera directly into the TV's video input jack. As an experiment I tried shooting the same subject at 3 different resolutions, but I was unable to discern any difference between the photos as viewed on the TV.

2) I saved the images as jpg files, copied them onto a CD and played them on my Sony DVD player, which supports this feature, and on several other TVs. I tried this with both full-sized and resized (to 640x480) images.

3) I created an SVCD (Super Video CD) and played it in my DVD player. Again, I mixed full sized and resized images but could discern very little difference between them.

4) I created a DVD slideshow using Roxio's Easy Media Creator (I used the "Create Slideshow" and "DVD Builder" features), and played it on several different TVs.

The results have been uniformly bad, and I can hardly tell any difference between the various methods. Certainly none of them stands out as a clear winner. Even when I view my images on a good quality widescreen LCD TV the fine details seem to disappear and the imagesare blurry. I have concluded that the problem is almost certainly related to the limited display resolution of TV sets and thus cannot be solved without upgrading to a high-resolution TV and DVD player.

Of course, I was able to create terrific special effects using the DVD slideshow software (background music, on-screen menu, transitions, videos mixed with stills, etc.), but what good are all those fancy features when the image quality is so poor?

And yet, I see a wide variety of DVD slideshow software being advertised on the web, complete with promises such as "your photos will look great on TV". The ads state that the resolution will be as high as 704x576 (or some such), and although this may sound like a lot for a television set, it doesn't even come close to the resolution of the original photos. How can such a huge loss of resolution "look great on TV", especially when viewed on a large screen? (I believe that the highest possible DVD resolution is 720 x 480 for NTSC, so that's got to be the limit, right? Until we all move to HD-DVD players, that is.)

From browsing the various newsgroups it is apparent that thousands of people out there are happily creating DVD slideshows and discussing how great they look. Am I missing something here, or is the large reduction in image quality a non-issue for most users?

It surprises me that our once-magnificent slide projectors have become a dying breed, and yet we have nothing of comparable or better quality to replace them with.(This reminds me of the current trend in music in which vast numbers of users seem to prefer highly compressed mp3 filesto good quality recordings).

What do others on this board think about the display quality of digital photos as viewed on a TV set?
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Old Nov 1, 2005, 5:20 PM   #2
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I agree that in general slideshows on TV do not look as good as prints, but I have had fairly good results ... perhaps because I am not using "slideshow" software but Pinnacle Studio 8 and 9video software.

I have done both slides-only with tons of effects (including music and sounds), and slide+video, again with lots of effects ... Studio 8 or 9makes recording sound+digital photos (which several digital cameras can do) worth it on occasion. The result is an "industry standard" DVD video that reproduces just like any video DVD does on a television.

Nonetheless, the display is still only so-called DVD-quality andthe resolution of current televisions as compared to computer monitors precludes the non-movingstills looking all that good, while the eye appears to fool us into thinking moving videos are ofsuperior quality.

Displaying those same photos using a portable DLP presentation projector from my laptop onto a screen, on the other hand, seems to make a much better presentation! The resolution is so much better! At least that has been my experience.
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Old Nov 2, 2005, 7:36 AM   #3
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Daniel T wrote:
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What do others on this board think about the display quality of digital photos as viewed on a TV set?
I dunno, since I've never done it that way, but if you're interested in producing better quality displays, why not try a digital projector? I've done that and gotten good results with slide shows. --The projectors aren't cheap, but I would guess that's the way to go for best quality with large screen.

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Old Nov 2, 2005, 11:55 AM   #4
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Still, they won't be as good as old fashioned slide projection. Isn't slide film supposed to have great resolution?

Most digital projectors have a resolution of 1024x768 AFAIK, which is maybe ok, but no way comparable to slides. Our DVD player is able to browse jpgs from an ordinary CD. But get this - it seems to resample them to DVD resolution in its cache, so if you zoom in, you see massive square pixels, even though the actual file has plenty detail.:roll:

I believe it may actually be possible to get some photo labs to expose your digital images onto 35mm slides. It may seem strange, but it might just be mad enough to work. I guess that would be the best quality for the kind of display you want to do. I don't know how the cost would compare to ordinary prints.


p.s. mp3s , as are jpegs. Lossy compression is great, but slides and vinyl do have their advantages.
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Old Nov 3, 2005, 2:26 PM   #5
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I'm a recent convert to digital imagery and this was my first DVD-slideshow. Having previously experienced slide film and slide projectors, I guess my expectations were a bit too high. Now that I think about it, the DVD-video NTSC resolution of 720x480 isn't even half a megapixel, and here I am trying to show it on a large screen. No wonder the detail is gone!

Also, I think that the image composition makes a big difference. I noticed that my wide-angle scenery shots lost most of their detail and looked quite flat and dull when viewed on TV, but my closeups of people and places were acceptable. Also, my short movie clips (shot at 640x480, with sound) came out beautifully.

hgernhardtjr wrote:
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Nonetheless, the display is still only so-called DVD-quality andthe resolution of current televisions as compared to computer monitors precludes the non-movingstills looking all that good, while the eye appears to fool us into thinking moving videos are ofsuperior quality.
I think you are right that a TV set displays motion much better than stills, at least as far as our perceptionsare concerned.

I would be willing to bet that most of the people who are satisfied with the quality of their DVD slideshows have not seen or worked with many real (using slide film and a slide projector) slideshows. Could this be one of those generational things? If you don't know what you're missing, you can't really miss it. (But hey, I'm not THAT old...)
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