PNG files - none or interlaced?

Question

Level 1

90 points

PNG files - none or interlaced?

Hello

Wondered if I need to choose NONE or INTERLACED when I make my psd's into PNG's for this video I'm editing, SD, probably to be shown from DVD only on a PC's LCD monitor? I tried a test (on my MAC 17" screen) and I can't notice a difference - my png slowly twists and zooms in and is part of a moving graphic. Slight problem on its horizontal lines, whether I choose none or interlaced.

I've placed the DV/DVCPRO NTSC seq into an uncompressed 8 bit timeline for the text and graphics sake, which does help, but I can't see a difference between making my pngs "none" or "interlaced" in the Photoshop save menu...is there a real difference?

Thanks

K

Message was edited by: Kent Beeson1

powerbook G4, Mac OS X (10.4.11), FCP Studio, DVD SP 4

Posted on Jan 4, 2008 4:52 PM

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Answer 1

javabob

Level 3

670 points

Jan 4, 2008 5:45 PM in response to Kent Beeson2

where you might see a difference is once you bring the images into FC, under "field dominance" you have "upper", "lower", and "none". "none" usually helps get rid of flickering.

so I would choose "none" in photoshop too.

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Answer 2

Kent Beeson2 Author

Level 1

90 points

Jan 4, 2008 7:13 PM in response to javabob

Very good - so are you saying that if my edited seq is DVCPRO NTSC DVcam footage with livetype graphics/text, I can make that seq have none (instead of lower) and it'll be OK both for the graphics and the dvcam SD footage? Then when I copy all into an uncompressed 8 bit timeline, none is fine as well? And this will get rid of the png flickering?

Sounds good if true - is it?

K

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Answer 3

Kent Beeson2 Author

Level 1

90 points

Jan 4, 2008 7:35 PM in response to Kent Beeson2

I just thought of something - so if I turn my seq into "none" does that mean I also have to go back and turn my couple of dozen livetype graphics and text into "none" since currently they are all "lower"...or is it good enough to just change the edited seq into "none"?

K

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Answer 4

Jim Cookman

Level 7

23,447 points

Jan 4, 2008 7:37 PM in response to Kent Beeson2

There's so much wrong here I'm getting a headache. DV is interlaced, lower field dominant.

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Answer 5

Kent Beeson2 Author

Level 1

90 points

Jan 4, 2008 7:46 PM in response to Jim Cookman

Yes, DV is interlaced, lower but does that mean one can't make the seq into "none"? I just did a few seconds test and both the dvcam and graphics text play very good/clean under none now - if the final delivery is a PC LCD monitor from a DVD is "none" a viable option? Won't be played on TV monitor.

K

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Answer 6

Ken Evans

Level 2

294 points

Jan 5, 2008 3:09 AM in response to Kent Beeson2

The interlace option for PNG's has nothing to do with the interlace system on televisions. PNG's were a graphic meant to replace lossy GIF images with a better system and lower filesize.

Interlacing in this instance means the passes required by a web browser to make for rendering the image.

PNG uses a sophisticated scheme which begins rendering the image after only 1/64 of the data has arrived in web browsers. PNG's 7 pass scheme fills in increasing amounts of detail both horizontally and vertically. Interlacing increases the file size. You may find that with PNG's better compression fewer images will need interlacing...again for the web!

Don't convert from PSD to PNG, just use the PSD!!

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Answer 7

Kent Beeson2 Author

Level 1

90 points

Jan 5, 2008 9:07 AM in response to Ken Evans

Thanks very much - this was the kind of help and info I was looking for -

K

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Answer 8

Kent Beeson2 Author

Level 1

90 points

Jan 5, 2008 10:09 AM in response to Ken Evans

A question re: pds's - if I don't need the psd's layers, is it better for FCP and quality to flatten the psd in Photoshop or leave it with its layers?

Thanks

K

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Answer 9

Studio X

Level 7

27,229 points

Jan 5, 2008 10:11 AM in response to Kent Beeson2

If you don't need the layers, flattening is preferred.

x

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Answer 10

Kent Beeson2 Author

Level 1

90 points

Jan 5, 2008 10:13 AM in response to Studio X

Excellent - thank you

K

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Answer 11

Jan 5, 2008 7:49 PM in response to Kent Beeson2

Thanks very much - this was the kind of help and info I was looking for -

Fortunately for us, you don't get to choose what kind of help you receive. We see lots of bad advice around here; myths perpetuated, errors compounded, typos worshipped. Wait till you see the responses you are going to get to your sonn-to-be-posted inquiry about scanning resolution for stills to be used in video.

Another thing about psd layers, layer effects or styles will not come across unless they are flattened. I hate Photoshop.

bogiesan

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