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Stills resolution for HD project
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You don’t have to worry about the dpi. This is just the way the picturte is displayed. QT display 72dpi when you set the viewer to 100%.
If you open a 300 dpi picture with QT you will get a huge screen 4 times bigger than the one you get when you open the same file in Photoshop.
So what is important is the total number of pixels. FC doesn’t care about the dpi.
rafael -
Rafael,
I beg to differ. Technically, you are correct, but I have done several tests with hirez and low rez images of the same frame size, and the higher rez images CAN cause much more artifacting than the low rez ones, depending on the subject matter and the movement/scaling. Note I said CAN, not will. And, FCP does behave differently with the hirez images, it slows it down. It’s just wise to always optimize stills the way Walter describes at 72 dip at 2x the frame size. Otherwise, you’re just asking for problems.
My two cents.
Have a wonderful day.
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[rafalaos] “So what is important is the total number of pixels. FC doesn’t care about the dpi.”
it actually does. 300dpi images cause FCP to operate much slower than 72dpi images just because they are such larger files. When possible, always work in 72.
Walter Biscardi, Jr.
Biscardi Creative Media
HD and SD Production for Broadcast and Independent Productions.STOP STARING AND START GRADING WITH APPLE COLOR The new Color Training DVD now available from the Creative Cow!
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Chris and Walter, I agree absulutly.
I meant that for some body that get confused with dpi’s and so, just forget about that and think in term of pixels.
72 dpi in Photoshop and doble wide of the sequence setting. A good formula for FC.
Raael -
File size is always proportional to the number of pixels and the bit depth. If you don’t change those things, the file size will remain the same, even if you change the dpi setting. Does FCP really care about dpi at all? Does dpi show up in the Item Properties?
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[Tom Brooks] “File size is always proportional to the number of pixels and the bit depth. If you don’t change those things, the file size will remain the same, even if you change the dpi setting”
Actually that’s completely incorrect. A 1500×1500 300dpi file that is about 45MB will be around 5MB or smaller if you do nothing but drop the dpi to 72.
dpi resolution IS directly related to file size.
Walter Biscardi, Jr.
Biscardi Creative Media
HD and SD Production for Broadcast and Independent Productions.STOP STARING AND START GRADING WITH APPLE COLOR
The new Color Training DVD now available from the Creative Cow! -
[walter biscardi] “Actually that’s completely incorrect. A 1500×1500 300dpi file that is about 45MB will be around 5MB or smaller if you do nothing but drop the dpi to 72. “
Walter,
This is completly wrong. If you make two documents in Photoshop with the same number of pixels, the size of the file is the same. The dpi it doesn’t matter.
What you have to be careful in Photoshop is when you change the resolution (image size).
If you have a 1500×1500 at 300dpi and you change to 72dpi, you will get a 360×360 picture.
So if you don’t want to loose definition you must set again manually the with and the height.
You will get your picture 1500×1500 at 72 dpi. The file size remais the same.
Rafael -
All I have to say is that it’s about the pixels and only the pixels. Make your stills at least the same pixel dimension as your sequence format. If you need to do moves on the stills, go for twice the dimension of the sequence format (as a starting point).
If your scanner only “speaks dpi” then find out what the resulting pixel dimension is when you use a certain dpi setting. It’s about the pixels. Always get back to pixels!
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[rafalaos] “Walter,
This is completly wrong. If you make two documents in Photoshop with the same number of pixels, the size of the file is the same. The dpi it doesn’t matter.”I’ve been creating animations in Photoshop and After Effect for 10 years now and as I have always seen, the higher the dpi, the larger the file size.
We do this all the time with our animations, creating a character in 300 – 600dpi in Photoshop working in a very large frame size with a lot of resolution so we will be able to zoom in once I move into After Effects.
Once we’re done, we drop the dpi to 72 but we don’t allow Photoshop to ReSample the image. This drops the file size by around 50 – 80% depending on how many layers are in the file.
Actually video is a good correlation. Uncompressed SD video creates larger files sizes than compressed video files even though they are the same frame size. Why? Because there is more information in the file. The larger dpi setting in Photoshop essentially gives the image printer more information to print, thus the file size is larger.
This is especially true when scanning images.
Walter Biscardi, Jr.
Biscardi Creative Media
HD and SD Production for Broadcast and Independent Productions.STOP STARING AND START GRADING WITH APPLE COLOR
The new Color Training DVD now available from the Creative Cow!
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