Photozoom DPI?
- Thread starter braw
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braw
Well-known member
Re: Photozoom DPI?
I guess what I'm saying is, there are different pixel counts on different CCD's. SD always ends up at 720x480. What is the equivelant dpi for that. Like 72dpi is for web images, 300-600dpi for print reguardless of size.
The XL2 samples images with smaller pixels packed into the same area. Is 72 sufficient, is that just the default for Photozoom, is that the default for SD motion video? Is it even relavant to video? If I blow 480p to 720p, do I also change the dpi?
I guess what I'm saying is, there are different pixel counts on different CCD's. SD always ends up at 720x480. What is the equivelant dpi for that. Like 72dpi is for web images, 300-600dpi for print reguardless of size.
The XL2 samples images with smaller pixels packed into the same area. Is 72 sufficient, is that just the default for Photozoom, is that the default for SD motion video? Is it even relavant to video? If I blow 480p to 720p, do I also change the dpi?
scharky
Veteran
Re: Photozoom DPI?
Like uslisses said, DPI has nothing to do with images on the screen.If the image is 720x480 it will be the same size on the screen whether it be 72dpi or 600dpi. DPI is only usefull when printing. So just leave the dpi alone in Photozoom (it assumes that you are making a print so it gives you that option). just change the pixel count and you will be fine.
Like uslisses said, DPI has nothing to do with images on the screen.If the image is 720x480 it will be the same size on the screen whether it be 72dpi or 600dpi. DPI is only usefull when printing. So just leave the dpi alone in Photozoom (it assumes that you are making a print so it gives you that option). just change the pixel count and you will be fine.
braw
Well-known member
Re: Photozoom DPI?
[quote author=scharky link=board=Events;num=1106007593;start=0#4 date=01/18/05 at 12:11:21]BTW, 72dpi isn't the default, that is what the image is set at. If you uprezz it to 1280x720, it will still be 72dpi.[/quote]
Thanks Scharky. I wasn't sure if it was relevant. So, if the projects ends up on DVD, is there any reason to uprez? Is it only useful for letterboxed or cropped stuff?
By the way, what's up with that Awake project? I found your site and it looks pretty damn cool from what you have up there.
[quote author=scharky link=board=Events;num=1106007593;start=0#4 date=01/18/05 at 12:11:21]BTW, 72dpi isn't the default, that is what the image is set at. If you uprezz it to 1280x720, it will still be 72dpi.[/quote]
Thanks Scharky. I wasn't sure if it was relevant. So, if the projects ends up on DVD, is there any reason to uprez? Is it only useful for letterboxed or cropped stuff?
By the way, what's up with that Awake project? I found your site and it looks pretty damn cool from what you have up there.
scharky
Veteran
Re: Photozoom DPI?
The only reason you would want to uprez is if you shot 4x3 and cropped in post (or letterbox) and then wanted to have a true widescreen DVD. And for that you would only be stretching your footage vertically. Just remember that the DVD spec is still only 720x480, even for widescreen.
It's funny you should ask about Awake. I will have a trailer posted in 2 days, I think people are catching on to my (only 5 days left) post in the screengrabs section. Right now I am just waiting for the composer to finish the music for the trailer, and then I'll post it for ya'll.
The only reason you would want to uprez is if you shot 4x3 and cropped in post (or letterbox) and then wanted to have a true widescreen DVD. And for that you would only be stretching your footage vertically. Just remember that the DVD spec is still only 720x480, even for widescreen.
It's funny you should ask about Awake. I will have a trailer posted in 2 days, I think people are catching on to my (only 5 days left) post in the screengrabs section. Right now I am just waiting for the composer to finish the music for the trailer, and then I'll post it for ya'll.
braw
Well-known member
Re: Photozoom DPI?
Scharky, why is it that even before I change the settings in Photozoom does the picture appear to process. When you load up an image, it scans and sharpens it with the default settings. Is this a "trick" that's in the software for making it look like it's doing something? In theory it shouldn't be uprezzing until I change the size right? Does it just auto sharpen no matter what you put in?
Scharky, why is it that even before I change the settings in Photozoom does the picture appear to process. When you load up an image, it scans and sharpens it with the default settings. Is this a "trick" that's in the software for making it look like it's doing something? In theory it shouldn't be uprezzing until I change the size right? Does it just auto sharpen no matter what you put in?
scharky
Veteran
Re: Photozoom DPI?
I've noticed that too. I can't really tell you. I think that it is applying some sharpening to the original image. I think it is just part of the uprezzing progress. There are other settings available so it doesn't always auto sharpen, just depends on the settings.
I've noticed that too. I can't really tell you. I think that it is applying some sharpening to the original image. I think it is just part of the uprezzing progress. There are other settings available so it doesn't always auto sharpen, just depends on the settings.
braw
Well-known member
Re: Photozoom DPI?
[quote author=scharky link=board=Events;num=1106007593;start=0#8 date=01/18/05 at 15:14:46]I've noticed that too. I can't really tell you. I think that it is applying some sharpening to the original image. I think it is just part of the uprezzing progress. There are other settings available so it doesn't always auto sharpen, just depends on the settings.[/quote]
I'll have to investigate further as well. I hear that there was a possibility of Shortcut making a version specifically for video. I sure hope they or someone else does. I get a little confused with the usefulness of settings based on images for print as opposed to video.
[quote author=scharky link=board=Events;num=1106007593;start=0#8 date=01/18/05 at 15:14:46]I've noticed that too. I can't really tell you. I think that it is applying some sharpening to the original image. I think it is just part of the uprezzing progress. There are other settings available so it doesn't always auto sharpen, just depends on the settings.[/quote]
I'll have to investigate further as well. I hear that there was a possibility of Shortcut making a version specifically for video. I sure hope they or someone else does. I get a little confused with the usefulness of settings based on images for print as opposed to video.
Barry_Green
Moderator
Re: Photozoom DPI?
[quote author=braw link=board=Events;num=1106007593;start=0#2 date=01/18/05 at 11:59:23]I guess what I'm saying is, there are different pixel counts on different CCD's. SD always ends up at 720x480. What is the equivelant dpi for that.[/quote]
DPI is completely irrelevant in video, because DPI refers to dots-per-inch. How many inches are there in video?
Let's take the example of viewing it on a 2" LCD TV. 720 dots across, on a 2" screen, = 360 DPI. Then take that exact same video and project it on an LCD projector on a 10' wide screen. 720 dots across on a 10' screen = 6 DPI. Yet it's the exact same video being played on both sources.
That's why DPI is irrelevant in video -- because there's no way to know what size the image will be viewed at, so there's no constant for "inches" in the dots-per-inches to reference.
[quote author=braw link=board=Events;num=1106007593;start=0#2 date=01/18/05 at 11:59:23]I guess what I'm saying is, there are different pixel counts on different CCD's. SD always ends up at 720x480. What is the equivelant dpi for that.[/quote]
DPI is completely irrelevant in video, because DPI refers to dots-per-inch. How many inches are there in video?
Let's take the example of viewing it on a 2" LCD TV. 720 dots across, on a 2" screen, = 360 DPI. Then take that exact same video and project it on an LCD projector on a 10' wide screen. 720 dots across on a 10' screen = 6 DPI. Yet it's the exact same video being played on both sources.
That's why DPI is irrelevant in video -- because there's no way to know what size the image will be viewed at, so there's no constant for "inches" in the dots-per-inches to reference.
braw
Well-known member
Re: Photozoom DPI?
[quote author=Barry_Green link=board=Events;num=1106007593;start=0#10 date=01/18/05 at 22:04:58]
DPI is completely irrelevant in video, because DPI refers to dots-per-inch. How many inches are there in video?
Let's take the example of viewing it on a 2" LCD TV. 720 dots across, on a 2" screen, = 360 DPI. Then take that exact same video and project it on an LCD projector on a 10' wide screen. 720 dots across on a 10' screen = 6 DPI. Yet it's the exact same video being played on both sources.
That's why DPI is irrelevant in video -- because there's no way to know what size the image will be viewed at, so there's no constant for "inches" in the dots-per-inches to reference.
[/quote]
Makes complete sense Barry. Would you happen to know what size is usually used when DV or HD is blown up to film? I'm sure they use an uprezzing deck or proprietary hardware or software for that. Do they use 720p, 1080p, or even higher? Not that I plan on going out to film anytime soon, just curious.
[quote author=Barry_Green link=board=Events;num=1106007593;start=0#10 date=01/18/05 at 22:04:58]
DPI is completely irrelevant in video, because DPI refers to dots-per-inch. How many inches are there in video?
Let's take the example of viewing it on a 2" LCD TV. 720 dots across, on a 2" screen, = 360 DPI. Then take that exact same video and project it on an LCD projector on a 10' wide screen. 720 dots across on a 10' screen = 6 DPI. Yet it's the exact same video being played on both sources.
That's why DPI is irrelevant in video -- because there's no way to know what size the image will be viewed at, so there's no constant for "inches" in the dots-per-inches to reference.
[/quote]
Makes complete sense Barry. Would you happen to know what size is usually used when DV or HD is blown up to film? I'm sure they use an uprezzing deck or proprietary hardware or software for that. Do they use 720p, 1080p, or even higher? Not that I plan on going out to film anytime soon, just curious.
Barry_Green
Moderator
Re: Photozoom DPI?
Depends on who's doing it, and what size you're blowing up to (16mm or 35mm), and what their budget is.
DVFilm, I believe, up-rezzes to HD 1920x1080x24p before transferring.
Some effects houses will do a 4000x3000 scan (a "4k" scan) and some will do a 2000x2000 scan (a "2k" scan) of the film, composite their effects onto it, and then transfer those results back out to film.
Depends on who's doing it, and what size you're blowing up to (16mm or 35mm), and what their budget is.
DVFilm, I believe, up-rezzes to HD 1920x1080x24p before transferring.
Some effects houses will do a 4000x3000 scan (a "4k" scan) and some will do a 2000x2000 scan (a "2k" scan) of the film, composite their effects onto it, and then transfer those results back out to film.
braw
Well-known member
Re: Photozoom DPI?
WOW
That's some serious rez. I took from your breakdown from another thread that it does little to no good to uprezz something if it ends up on DVD (aside from cropped 4x3 footage) since in pixel land, downrezzing DV discards pixels. Film on the other hand is scanned at the end resolution isn't it?
Random side note. It seems that movies like 28 Days Later and Dancer in the Dark, when put on to DVD, are scans off the film out version. At least that's what it looks like to me. If that's true, why do they do this instead of transferring it digitally? Is there a way to simulate this effect that you know of?
By the way, thanks for the endless geyser of knowledge you and many others lend to this board.
WOW
That's some serious rez. I took from your breakdown from another thread that it does little to no good to uprezz something if it ends up on DVD (aside from cropped 4x3 footage) since in pixel land, downrezzing DV discards pixels. Film on the other hand is scanned at the end resolution isn't it?
Random side note. It seems that movies like 28 Days Later and Dancer in the Dark, when put on to DVD, are scans off the film out version. At least that's what it looks like to me. If that's true, why do they do this instead of transferring it digitally? Is there a way to simulate this effect that you know of?
By the way, thanks for the endless geyser of knowledge you and many others lend to this board.
Barry_Green
Moderator
Re: Photozoom DPI?
Yes, I'd agree that uprezzing does you no good if ending up on DVD.
Film may be scanned at whatever resolution the target medium is, or they may scan it at a higher resolution and then downrez, or... well, whatever they want. I believe that most Hollywood DVD's are produced by transferring the film at 720x480 resolution and then authoring an MPEG-2 from that.
As far as why the video-originated films are transferred back from the film print to DVD, rather than using the video original... can't speak as to why those decisions are made in each case, but I'd suspect that there was quite a bit of color correction and image cleanup being done after the up-rez and before the transfer to film. If so, you'd want to capture that higher quality (as well as whatever image enhancement was done during the film transfer) rather than go from the original, original DV source... but that's just a guess as to why those particular films were done that way, and I haven't seen either on DVD so I don't know, just guessing.
Yes, I'd agree that uprezzing does you no good if ending up on DVD.
Film may be scanned at whatever resolution the target medium is, or they may scan it at a higher resolution and then downrez, or... well, whatever they want. I believe that most Hollywood DVD's are produced by transferring the film at 720x480 resolution and then authoring an MPEG-2 from that.
As far as why the video-originated films are transferred back from the film print to DVD, rather than using the video original... can't speak as to why those decisions are made in each case, but I'd suspect that there was quite a bit of color correction and image cleanup being done after the up-rez and before the transfer to film. If so, you'd want to capture that higher quality (as well as whatever image enhancement was done during the film transfer) rather than go from the original, original DV source... but that's just a guess as to why those particular films were done that way, and I haven't seen either on DVD so I don't know, just guessing.