PLEASE HELP!!! Widescreen Aspect Ratios!

You'll have to try it out and report back. 🙂

Ok, I'll be sure to let you know ASAP - thanks again.

- Jordan

Hi folks, here is what I've come up with so far...

After much experimentation and assumption making, I have determined that the image size of Anamorphic 16:9 NTSC video is not 720x405, or 854x480, as some have suggested. In fact, it remains unaltered at 720x480. The thing is, the pixels aren't square...

I'm not an expert, but I think that Apple doesn't change the dimensions of the image at all, rather, they implement non-square pixels to create the Anamorphic widescreen image. If anybody can confirm or deny this, I'd appreciate it, because it makes or breaks my logic that follows.

So, assuming that Anamorphic DV is 720x480 pixels at all times in the workflow, to determine how many pixels to matte out I calculated as follows:

720 / 2.00 = 360 pixels (desired # of pixels in the height of the image)

480 - 360 = 120 (# of pixels that need to be cropped out)

120 / 2 = 60 (# of pixels that need to be cropped out from both top and bottom)

Using Adobe Photoshop CS2, I created a black bar image that is 720x60 pixels, setting the "NTSC DV Widescreen" pixel aspect ratio setting.

I then saved this as a non-interlaced PNG file and imported it into Final Cut Pro. In the Final Cut Pro browser, I set the "Anamorphic" check box to again specify the "Widescreen" pixel aspect ratio.

I put two of these black bars over my video, one at the top and one at the bottom. I noticed in the "distort" properties, the aspect ratio of my black bars had automatically been set to "12.x" (I forget what the "x" was). I don't understand why this happened or what this means, but I changed the setting to "0" signifying a "native" aspect ratio for the black bars.

So, presumably, I now have my 2.00:1 letterboxed image, within the 16:9 DV Anamorphic frame... right? Well, here's the rub:

I exported a small portion of the above into Discreet Cleaner, a product that allows you to transcode your video. In Cleaner, there is a very useful feature where you can set the "display aspect ratio" and "crop" aspect ratio independently from one another. I set the "display aspect ratio" to 16:9 and the "crop" aspect ratio to a constrained proportion of "2.00:1" to see if the resulting crop would match up perfectly with my black bars.

It didn't.

So then, I wanted to try the whole thing with a standard aspect ratio. I ran all my calculations again for the more common 1.85:1 aspect ratio. Here is my math:

720 / 1.85 = 389

480 - 389 = 91

91 / 2 = 45.5 (pixels to be cropped from both top and bottom).

I made my 720x45 bars again in Photoshop using the manner described above (Photoshop will not let you use fractions of pixels so I rounded down to 45).

I brought the black bars into Final Cut Pro as PNG files using the manner described above and compared them to the automatically generated black bars from Final Cut Pro's "Widescreen" matte filter.

Much to my surprise, my bars were about twice as big as Final Cut Pro's. Clearly, one of us is wrong... and my guess is that it has to do with the aspect ratio of the non-square pixels.

Sure enough, bringing the footage into Cleaner proved there was some discrepancy. Cleaner's 1.85:1 crop fell somewhere in between Final Cut's and my own.

So who is right? How can we accurately measure how many pixels to crop off of 16:9 Anamorphic DV video in order to derive a given letterboxed aspect ratio? This issue seems needlessly complicated and confusing. Perhaps somebody with more experience can shed some light on my errors and what I'm overlooking.

Thanks very much!

- Jordan

Hi, hanumang, thank you for your post! I have a couple of questions regarding your numbers:

First, where did you get 780x405 as a frame size?

Second, is it correct to say that 16:9 = 854x480 or 864x480, as you have indicated (I have always heard it said '854 or sometimes '856')?

Also, do you trust the settings that the Final Cut Pro Matte generates to be good for Anamorphic material?

Last, in my version of Photoshop (CS2) should I bother with "Widescreen Pixel Aspect?" It seems like you used standard quare pixels in your workflow.

Thanks again for your continued help!

- Jordan

Yes, I used your numbers and did what you did with 720x22 black bars. Again, I export my final composition into Cleaner to "check" the results, and confusingly, your/our bars still seem to be cropping LESS than Cleaner cropps.

Since cleaner is the only application in this workflow where I can actually type-in-and-specify "2.00:1" I have been using this as a guide. Using Cleaner's settings, the program indeed spits out an image that is 720x360, as your logic would suggest it should.

Still, there seems to be an unsolved issue of figuring out how different applications (Photoshop / Final Cut Pro / Cleaner) handle Anamorphic pixels across various formats (Quicktime, PNG, PSD).

Here's another clue:

I put the full 720x480 16:9 Anamorpic image into Cleaner. Set the crop aspect ratio constraint to "2.00:1." I then exported a few seconds of video (resulting in a 720x360 Quicktime).

I exported a PNG still of the above and imported that into a Photoshop CS2 comp of 720x480 with the "D1/DV NTSC Widescreen" (correct) pixel aspect ratio.

When I measured the distance from the top and bottom of the 720x360 image to the top and bottom of the composition (the part that would be covered by a black bar) the size is 60 pixels, not ~22.

BUT, as we all know by now, this just can't be right somehow, because producing 1.85:1 using the above means produces a radically different crop than the "constant" of FCP's 1.85:1 matte generator.

So again, I'm going around in circles here.

- Jordan

Hi again, hanuman,

I agree with you about the variance. I have spent enough time in Telecine sessions to know that every piece of hardware handles Anamorphic/Letterbox issues differently. But the variance I'm seeing here is huge.

I think that at this point, there are two issues to resolve about this workflow, and they both come down to: "Which method is superior (more accurate):"

1.) Should I work with Square Pixels or Anamorphic Pixels in Photoshop?

2.) Should I calculate using 720x480, 854/864x480, or 720x405 for Anamorphic DV?

Depending on your answers to the above two questions, you will come up with radically different results. But only "one" combination can result in a truly "correct" ratio.

- Jordan

Dear hanumang,

This project will go out (next week) to DVD. The cinematographer wants an Anamorphic 16:9 DVD (no argument there) with a 2.00:1 letterboxed image. Apparently, that's what he and the director intended when they shot (these guys don't like to use anything to do with "standards" or "presets").

At any rate, I will also be producing trailers in the 2.00:1 aspect ratio for use on the web. My workflow for this is to export from FCP as "uncompressed 8-bit" and then use Cleaner to scale and crop the image to 720x360, also as uncompressed video. I then put that uncompressed 8-bit, cropped video into Apple Compressor and compress to H.264. The result is excellent, on par with what you see as “HD 480p” on Apple’s QuickTime website (it helps to have film-based material, believe me).

The only real relevance of Cleaner in our discussion here is that I was using it as a double-check to try to verify what Final Cut Pro and Photoshop are doing. Unfortunately, I have inconsistent results across all three apps.

You have been invaluably helpful in this matter, but I also hope somebody else will chime in, perhaps who is experienced with the nuances of Photoshop CS2 and it's pixel aspect ratio presets (perhaps they are what’s misleading me).

- Jordan

Ok, I think that I finally solved this problem once and for all. As you know, where we last left off, I was creating a 720x480 composition in Photoshop CS2, specifying a "D1/DV NTSC Widescreen" pixel aspect ratio, then masking the top and bottom to create a center aspect ratio of 720x360, which we determined was equivalent to 2.00:1.

The resulting mattes were 60 pixels each by my calculations (480-120 = 360) or ~22 pixels by hanumang's method (read his posts above). The thing is, when imported into Final Cut Pro, my mattes looked too big, and when tested by comparison to the crop function found in Discreet Cleaner, it was clear they were wrong.

Well, I finally figured out the problem, and the problem is pixels! Photoshop CS2 is kind enough to offer the "D1/DV NTSC Widescreen" pixel aspect ratio, but this was VERY misleading, as this is only a DISPLAY aspect ratio (actually, this fact is quite clear, I was just missing the connection entirely)! The resulting files that are “Saved As” still always have a SQUARE pixel aspect ratio, rendering my calculations virtually meaningless.

Final Cut Pro tried to warn me; way back in an earlier post I had mentioned that when importing my PNG files into Final Cut Pro, the "distort" property was mysteriously set to "12." This would have actually been a good thing, if I had left things along, as it was automatically correcting the discrepancy between the square pixels of my PNG file and the Anamorphic pixels found in my 16:9 composition.

But on the plus side, PSD files (native Photoshop files) carry METADATA, which Final Cut Pro reads brilliantly. When importing a native PSD file, Final Cut Pro recognizes the desired pixel aspect ratio with ease and places clips onto my timeline with no distortion, thereby reproducing what I had accurately designed in Photoshop.

Cleaner confirms this too! Their crop function comes in right where it's supposed to be, just underneath my black bars. ALSO, my double-check test of creating a 1.85:1 matte came through as well. It's identical to the 1.85:1 matte generated by Final Cut Pro.

So, hanumang, we were both right; what you were doing with 854x480 and 720x405 works perfectly if you're consistently staying within SQUARE pixel formats. What I was doing with 720x480 in the equations was also correct, assuming that I stayed with Anamorphic pixels across the board. What I found was that my workflow wasn't consistent all the way through, and that's where I was getting into trouble.

So, just to recap; Photoshop CS's widescreen pixels are for display only! Exporting to another format such as PNG saves only square pixels. Saving in the native PSD format carries metadata, and it looks like Final Cut Pro reads it’s pixel information accurately. Mystery solved.

Thanks again to everyone, especially to hanumang, for your help with this matter. Any comments or corrections are, of course, always welcome.

- Jordan