Cable Box Output Resolution

I have two plasma TVs, an older Philips 1080i/720p and a newer Panasonic 1080p. I have Verizon FiOS with HD DVR that lets me choose 720p or 1080i output. Which should I choose for the best picture for watching sports? I seem to remember reading somewhere that 720p is best for sports and 1080i is better for movies, but I'm not sure if that still holds true.

Also, I'm considering getting a new 1080p set, and I see you have the Panasonic TC-P50ST30 rated as one of your Top Picks. I can get a good deal on the 60-inch version of this TV and was wondering if your review holds true for that size. I see you review a lot of 50-inch TVs, but not the 60-inch versions. Do the 60-inch versions lose picture quality because the screen is 10 inches bigger with the same number of pixels? Do they just make the pixels bigger?

Jay P.

You are correct that 720p is better for sports, but only if the action was captured by the camera and broadcast at 720p. The image above was probably captured at 1080i, which is apparent in the jagged edges that occur in moving objects—look at the edges of the white stripes on the uniform and the UCLA logo on the helmet—because the object has moved between the moment the odd-numbered lines of the image were captured and the moment the even-numbered lines were captured. If this image had been captured at 720p, the edges would be clean, not jagged.

The best choice for your FiOS box's output resolution depends on several factors. First, what is the channel broadcasting, 720p or 1080i? Some channels, such as ABC, Fox, and ESPN, capture and broadcast at 720p, while most others capture and broadcast at 1080i.

If you watch both types of channels, the video signal must be scaled at least some of the time, and this is performed in the FiOS box and/or TV. So the question becomes, which device does a better job of scaling (and deinterlacing in the case of 1080i)?

To find out, set the FiOS box to output 1080i and watch something on a 720p channel, such as ABC, Fox, or ESPN. Then, set the box to output 720p and watch something on CBS or NBC HD, which broadcast at 1080i. Finally, if possible, set the box to output whatever signal it receives without changing it (this setting is probably called something like "Source Direct" or "Native") and watch things on both types of channels. This forces the TV to do all required scaling and deinterlacing. Which way looks best?

Keep in mind that the Panasonic 1080p set will scale a 720p signal to its native resolution of 1920x1080, while the Philips probably scales 1080i and perhaps 720p to its native resolution. (You don't specify a model number, so I don't know what its native resolution is, but since it's older and you call it "1080i/720p," I suspect think it's probably 1366x768 or 1280x720, so it has to scale 1080i in either case, and it must also scale 720p if its native resolution is 1366x768.) Given all this, I suspect it will be best to have the FiOS box output whatever it receives without changing it, because the fewer scaling steps, the better.

Regarding the Panasonic TC-P50ST30 (reviewed here) and P60ST30, you are correct that the larger screen has the same number of pixels, and each pixel is bigger as a result. This means you can see any flaws in the picture more readily on the larger screen, especially if you sit close to it. However, at the optimum seating distance (about 8 feet for a 60-inch screen, 7 feet for a 50-incher) or farther, there should be no appreciable difference in picture quality. I'm convinced that our reviews of 50-inch models apply equally well to different sizes, as long as you don't change the relationship between seating distance and screen size.

If you have an A/V question, please send it to askhometheater@gmail.com.

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COMMENTS
mailiang's picture

Keep in mind that unlike computers, all TV's scale due to over scan. Therefore, you will usually get the best results by setting your cable or satellite box to native and just let your TV do what it has to do anyway. I never believed that the optimum seating distances are as close as what some of the videophiles suggest. For a 60 inch screen I personally recommend a seating distance of 10 ft or more, for a 50" at least 8 ft, other wise you will have a better chance at noticing certain HD artifacts and anomaly's like dithering or false contouring, especially on plasma displays, which are fairly common and at closer distances, can be distracting.

JudgeSmails's picture

Average viewers won't notice much of a difference in picture quality allowing the TV to do the scaling. One thing EVERYONE will notice is that when outputing native resolution from the cable box, most TVs will flicker when changing input resolutions. I know on my projector I leave my DirecTV box set to 720p 90% of the time to avoid the constant flickering when chaning channels. If I know I'm going to be stuck on 1 channel for an extended period of time, I will change the box to output native. DVDO EDGE GREEN makes big TVs happy!!!!

mailiang's picture

I also have DTV and I don't have that problem, but then again I'm not using a projector. Setting my HD DVR to native makes a noticeable difference in PQ on my late model plasma TV, which typically offers a fast response time.

JustinGN's picture

I'll take a resolution change flicker from my TVs over scaling artifacts any day, if only because the flicker only happens every resolution change, whereas artifacts are wholly dependent on the scaler used. Also, I agree, a DVDO EDGE processor should be an investment for anyone serious about getting the best picture possible from their display. I only wish I could get a non-switcher version, with one input each of HDMI, Component, RGBHV, S-Video and Composite, with a single HDMI output. My AVR does switching fine, but its video processor (Marantz SR6003) is incredibly buggy with analog signals.

tjuncewicz's picture

I've been reading all over about how no AV receiver can "downconvert" HDMI to component output due to HDCP copy protection, yet you can purchase a $40-$100 converter box (like the HDFury) that will do the job (with various hassles, limitations, and levels of success). Why is this the case? Is it some "agreement" that AV manufacturers have signed? Why does this not apply to the HDFury-type devices? Makes NO SENSE to me and is frustrating as I have an older 65inch Toshiba rear projection TV with only component inputs (no HDMI) and I have several HDMI output devices (Roku, Panasonic Blu Ray). I bought a cheapo $40 widget to do the downconversion which works ok but with a little bit of "snow" occasionally appearing (and issues with getting surround working via optical audio cable).

Until my TV dies, I'm stuck with this less-than-ideal setup unless I can find a receiver that can fix my woes and do the downconversion while still handling the surround audio. Any suggestions?

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