What is the best ppi or dpi in scanning for slideshows

[d_unbeliever]

What dpi or ppi should i set in my scanner in scanning my pictures to be used in slide shows?
300, 600 or 1200 ppi or dpi?
will it affect the quality of my video output?
will my output mpeg or video be bigger if i used higher resolution?

When i scan pictures sometimes i can't see the detail of the face of the people in the picture when i viewed the slideshow on my TV using VCD?
shall i increase the dpi or ppi of my scanning? or maybe use zoom/pan in my slideshow focusing on the faces? Sometimes i cant use SVCD on some of my projects so im stuck with VCD format.

Please guys hope you will help me with these...

Im using MemoriesOnTV and ProShow Gold version 2 to create VCD slide shows...

[redwudz]

600DPI is usually sufficient. 1200 will get you incredibily large files, especially if the source photo is large. 300DPI is usually more than enough for larger scans, like 8x10 inch. A really high DPI will result in an oversize picture which you may have to shrink to fit, so not much is gained.

[mikesbytes]

The bottom line is that it probably doesn't matter. But there are disadvantages of scanning above 300Dpi.
1. Large file sizes slow everything down.
2. You tend to pick up the 'dots' off the photo and may actually end up with worst looking photos.
If you are only scaning to put on a VCD, you might find that even lower than 300Dpi will produce the same result, with less waiting. It depends a lot on your scanner and software. Suggest the acid test. Scan the same picture at 100Dpi, 200Dpi, 300Dpi, 600Dpi and 1200Dpi. Convert them to a slideshow and see the results for yourself.

[d_unbeliever]

tnx guys for the very quick reply highly appreciated

[akbor75]

scanning 10x15 cm at 300 dpi will result in 1800x1200 pixels.
as you know dvd quality is less than 800x600 pixels, so 150 dpi will be sufficient. (ofcourse more may be needed when you want to use a part of the picture.)

[d_unbeliever]

i did tried to acid burn scanning at 300, 600, 1200 dpi
i did NOT really see any difference with with pictures scanned in 300, 600, and 1200 dpi when viewed in TV...

thanks a lot guys...because of you i will no longer waste my time scanning using 600 dpi and above for most of my projects which is quite slow in my scanner...

[huiwinsun]

I think u don't see any difference because the ordinary TV screen is only 75dpi (if I remember correctly...) Thks.

[mikesbytes]

Depends on the size of the original, as we have a fixed number of pixels across the screen, the dpi would depend on the size of the screen.

Try scanning at even lower resoutions, say 150Dpi should be plenty

[d_unbeliever]

is it ok to use 300 or 150 dpi scanned pictures even if i use zoom in those pictures in my slideshow. i planned to zoom on faces of the persons in the picture to get more detail...

i need to focus or zoom on faces in group pictures...will 300 or 150 dpi give me the sufficient detail or good quality output?

thanks alot again guys, hope others will also share experience on this...

[DaveS]

I've been scanning @ 600dpi then resizing to no larger than 720x480 (e.g. depends on proportions of original photo but typically resize the height to 480 and make sure the width is no larger than 720).

I would think that scanning at lower res. e.g. 300 or even 200/150 would work similarly, but for some reason, on some pictures, I found that the lower res scan would not produce great results...probably is the difference between the physical scan at a lower res and the mathamatecal resizing.

600 dpi is slower / larger file size though