View Full Version : Cropping to widescreen format
Justin Morgan August 13th, 2003, 12:11 PM Hi, I remember reading a post (I think by Ken Tenaka) saying that he likes to shoot in 4:3 and then crop to widescreen in post.
I'm using Final Cut Express and from what I can figure the only way to do this is to apply the 'widescreen' filter to each clip in my film - this is possible but slightly laborious...
Is there an easier way?
Devin Doyle August 13th, 2003, 01:04 PM What I used to do was overlay 16:9 bars I got off of a website. I can't specifically remember where I got them from, but they're nice tga files. I'd just key out the white in between the bars and overlay it on top of my footage. Email me and I can send it to you. (devin_doyle@hotmail.com) Of course I did all this in premiere so I don't have a clue about how to do it in FCP, although I imagine its just about the same process.
Nowadays I shoot with the cameras electronic 16:9. I used to do the process above until I read this:
http://members.macconnect.com/users/b/ben/widescreen/
Now he says it boosts your res, but really all you're doing in using in cam 16:9 is utilizing the DV stream more efficiently (read that on another post). So consider shooting with the in cam 16:9 next time. Since I don't have 16:9 guides and am tired of guessing where the widescreen frame ends this is a lot easier (on a GL1). Usually I'll edit my whole production, export it with lossless compression, and then import into a 4:3 project and tell it to remain in its original aspect ratio. Premiere generates the bars and I'm good to go. Once more, I dunno how FCP would handle it, but I'm sure it's about the same process. Good luck!
Boyd Ostroff August 13th, 2003, 02:31 PM <<<-- Originally posted by Devin Doyle : Nowadays I shoot with the cameras electronic 16:9. -->>>
I suggest you do some tests yourself if you want the best 16:9 with a 4:3 camcorder. My tests (http://www.greenmist.com/pdx10/mode) with the VX-2000 imply a very significant res boost by cropping in post instead of builtin 16:9 (~360 vs 240 vertical lines of resolution).
Read the American Cinematographer article about blowing up XL-1s footage for the film "28 days later" to 35mm 1.85:1, they chose to shoot 4:3 and crop in post.
I doubt that you can generalize about this sort of thing as different cameras handle builtin 16:9 differently.
Devin Doyle August 13th, 2003, 02:45 PM Boyd - I actually visited your site a while ago after perusing another debate on DVinfo about cropping vs. in cam 16:9. Eventually I will run my own tests to see what the best option is, however that link I posted (and I'm sure you're well aware of that test/site) used a GL1 for his test (same camera I'm using), and I'm comfortable with relying on his results for now. I really can't notice that much difference between the two, my eye must not be as discriminating as others around here! I suppose it's just one of those technical nit-picky things we dwell over.
I have read that american cinematographer article. I spose I need to go back and revise it. Boy I really hope they include a lot of behind the scenes documnetaries on the 28 days later DVD, I'm dying to get some detail on how they shot a lot of it!
BTW - you're doing a great service to the community by posting your own res tests on the VX2k. We appreciate it!
Boyd Ostroff August 13th, 2003, 03:17 PM Thanks for the kind words Devin! In some shots the difference may not be particularly apparent. But looking at the vertical res on the chart should tell the real story. Note the converging horizontal bars at the top of this image (http://www.greenmist.com/pdx10/mode/03.jpeg) of a res chart, shot with the VX-2000. In the example on the left the bars are pretty solid and distinct up to around 350 or 360. The example on the right (built-in 16:9) shows lots of degradation beyond about 240 or 250.
However from what I've read the GL-1 and GL-2 process 16:9 differently than the VX-2000 and you're probably right in your approach for this camera.
Ken Tanaka August 13th, 2003, 04:27 PM Justin,
Yes, when 16:9 is needed I do, indeed, shoot 4:3 (using the XL1s & GL2's 16:9 guide bars) and then crop the image in post.
Of couse, there are many versions of "16:9". In Final Cut Pro 4, the widescreen filter is the easiest tool to do the job. If offers several variations on the crop. It's best to do this last, if possible, to avoid unnecessary render time.
If you are compressing video for Web delivery you can also perform this crop with a tool like Cleaner 6.
Another other way to do this is to import a matte (still graphic from Photoshop or another graphic app) that features an alpha channel block in the middle where the image will appear. The top and bottom bars will be, of course, black. You can build one yourself pretty easily. Or you can visit Rob Lohman's great "Letterbox Calculator" (http://www.geocities.com/robvisuar/calc.htm) page to grab a matte.
Devin Doyle August 13th, 2003, 09:09 PM Boyd - I'd have to agree with you on the VX2K res tests. Vertical resolution is higher when cropped in post. I wish I could get my grubby paws on one of those resolution charts to test my GL1 myself. The only thing that really gets me down when shooting in 4:3 and then cropping is trying to imagine where the bars will cover. I know you can move the image up and down just in case you miscalculated (which is a nice feature, i might add of this method) but I'm concentrating on so many other things that it's easy to botch the shot! I know the GL2 & XL1s have those 16:9 overlays which help, just wish I had one on my GL1!
Ken - As always you get back to the main point! That calculator link is nice, I've bookmarked it for future reference. Thanks!
Boyd Ostroff August 13th, 2003, 10:11 PM <<<-- Originally posted by Devin Doyle : I wish I could get my grubby paws on one of those resolution charts to test my GL1 myself.-->>>
http://www.bealecorner.com/trv900/respat/#EIA1956
<<<-- I know the GL2 & XL1s have those 16:9 overlays which help, just wish I had one on my GL1!-->>>
How about using electrical tape or a china marker on the LCD screen?...
Devin Doyle August 13th, 2003, 11:23 PM <<<-- Originally posted by Boyd Ostroff : How about using electrical tape or a china marker on the LCD screen?... -->>>
I did use a piece of transparency with 16:9 bars on it, but it got a lot of grit in my LCD and was a pain to keep re-aligning. As to taping or marking my lcd directly...I don't think so. lol!
That res test is great though. Thanks for sending that through. I'm going to run that test tomorrow and post pics to my site...I'll update on the morrow. Thanks Boyd!
Justin Morgan August 14th, 2003, 06:38 AM Thanks
Ken - so the best way is indeed to use the Final Cut 'widescreen' filter. This may be a real rookie question but is there a quick and easy way of applying a filter 'to all'?
My other query is (as I haven't actually tested this myself). I can imagine that this technique will look fine when played on a 4:3 television but what happens to it when played on a widescreen TV - does the TV think that the black bars are actually part of the image? Is this a problem?
Justin Morgan August 14th, 2003, 10:22 AM Okay - I've found out how to do the 'apply to all' thing.
Also, from what I see it seems that hopefully a widescreen TV would NOT take the black bars as part of the image.
This is an assumption I am making based on the fact that when I double-click a clip that has had the widescreen filter applied the black bars do not appear - the areas where they would be are appearing as transparent. Excellent!
Somebody please correct me on this if this is an inaccurate assumption.
Boyd Ostroff August 14th, 2003, 01:03 PM I'm not sure what you mean by "transparent", but I suspect your logic is flawed. Unless you have flagged your footage as anamorphic 16:9 then a widescreen TV will just treat it like 4:3 (for all it knows you may *want* black bars on the screen). However, my Sony 16:9 monitor has menu options for how to scale footage to fit the screen. I believe one of the options will expand letterbox to fill the screen, but this is something which requires an action on the part of the viewer.
Ken Tanaka August 14th, 2003, 05:35 PM Justin: I can's say that using FCP's widescreen filter is the best technique for all applications but it's been the best way for most of mine. The exception is the work we do with our Lady X Films -- ladyxfilms.com -- project, where we do the crop in Cleaner 6 as we compress episodes.
Boyd is 100% correct. Cropped 4:3 footage, such as we're discussing here, is just cropped 4:3 footage. It's strictly a presentation style, not a different presentation format. Your standard television will display it fine. Try it.
Justin Morgan August 15th, 2003, 02:43 AM But what about a widescreen TV?
Ken Tanaka August 15th, 2003, 10:33 AM It depends on the specific features of the set. Typically, in such sets 4:3 footage can either be displayed centered with black bars on either side or stretched with no bars on the sides.
Justin Morgan August 15th, 2003, 10:40 AM But does that mean it would stretch the whole 4:3 image, including the black bars at top and bottom, to fill the screen - this would result in a horizontally stretched image - as it is taking 4:3 and stretching it to fill the screen rather than taking just the widescreen picture and using that to fill the screen.
Boyd Ostroff August 15th, 2003, 01:46 PM Justin, on my Sony SDM-V72W 17" HD LCD there are 4 different display modes: normal, letterbox, wide zoom and zoom. When I look at a letterboxed clip and put the monitor in "zoom" mode it nearly fills the screen. There's a narrow black band at the top and bottom. Maybe my letterbox mask on the clip I'm viewing is the wrong size? But it could also be that the LCD screen's physical dimensions aren't really 16:9 (it measures 14.7" x 8.8", or a 1.67:1 aspect ratio, a bit of a disappointment).
If I use "wide zoom" instead it looks like 2.35:1 letterboxed. This is because it stretches a 4:3 image to the full width of the screen without changing the height. The "zoom" mode stretches the image in both dimensions, and I assume it exists just for the purpose of filling the screen with letterboxed video. It should be noted however that images viewed this way look noticeably softer than real 16:9 DV footage.
Devin Doyle August 15th, 2003, 06:25 PM Boyd - would you mind telling me the process you went thru for your res test? I shot it, captured the images in premiere as uncompressed bitmaps, then went into photoshop and exported them for the web. The 4:3 footage isn't what I'm worried about however, how can I get the 16:9 images into photoshop whilst maintaining it's aspect ratio? As of now it does the stretch to fill the whole 720x480 frame.
My workaround: I used premiere and imported the 16:9 res images into a 4:3 project. I then told premiere that their aspect was 1.2 (NTSC DV widescreen), then told the clip to maintain its aspect (thus generating black bars in premiere) and then exported as an uncompressed targa and did my magic in PS. I'm just not sure if this process is degrading the image or not. I'd like to hear about your process before spending too much time making a page for my own tests when I did them wrong in the first place! Thanks Boyd!
Boyd Ostroff August 15th, 2003, 07:40 PM Well I use Final Cut Pro, not Premiere. But I think it would go the same way... if you import a 16:9 image into FCP at 720x480 you just need to resize it to 954x480 to have the correct aspect ratio on a computer screen with square pixels. This is assuming anamorphic 16:9.
If you are shooting letterboxed 16:9 then first use Photoshop to crop the image to the letterbox, which should be about 720x360. Then resize to 854x480.
Does this answer your question?
Devin Doyle August 15th, 2003, 08:03 PM ...sorta lol. My images are 720x480 with 1.2 aspect (16x9). Therefore they stretch in premiere to fill the frame in a .9 aspect (4:3) project until I tell the shots to remain in their original aspect, resulting in a 720x360 image with black bars on top and bottom. Getting the camera 16:9 images to show up in a 4:3 project without being stretched isn't the problem. I'm worried that when I export from premiere that the images are being degraded. I zoom in on the shots in PS and export from there.
Boyd Ostroff August 15th, 2003, 08:49 PM Sorry, I guess I don't understand. In Final Cut Pro it doesn't matter whether you set your sequence for 16:9 or 4:3. Either way, if you export a still frame as a JPEG it will be 720x480. If the original was an anamorphic 16:9 image you would need to stretch it using Photoshop to create an 854x480 image with square pixels.
Sounds like your question about image degradation is Premiere-specific and you might want to ask in the PC group?
Rob Lohman August 20th, 2003, 06:15 AM If you want a widescreen TV to automatically display the signal
in widescreen you must do the following:
1. crop the footage to widescreen 16:9
2. resample it back to full resolution of 720x480 or 720x576
3. when encoding the mpeg2 and authoring the DVD make sure you indicate the footage is in anamorphic format
That should take care of it. Also, make sure if you use my masks
or make your own with my calculator that you import the footage
AT THE CORRECT PIXEL ASPECT! Mostly NLE's default to a PA of
1.0 for a picture which is WRONG in this case.
|
|