Frankly, on higher end TV's (or even just better brands) one does not see the difference with either resolution for either picture or EPG. Most likely, it is how the HDTV is handling the conversion to its native resolution (in other words, OP, you see ALL images at your HDTV's NATIVE resolution no matter what the resolution of the source as the HDTV does the scaling just before displaying the picture. It may have to do with your recent calibration.
Look, I'm not against calibrations, but people should be aware that a calibration can allow one to see more FLAWS and even result in a worse "aesthetic" PQ. A calibration is a less "forgiving" picture because calibrations, in general bypass some of the electronics for PQ enhancement, and while some of those settings, especially the "noise" reducers are best left off, some of the processing is best left ON, for very good reasons that the PQ from the studio or network uplink will suffer somewhat when it reaches your HDTV. I really don't view my HDTV as a Conrac Monitor for a TV Production Studio.
Most calibrations focus on the greatest/best contrast and accurate color, which is not necessarily what people view as the "best" color, well aware that the HDTV is enhancing the saturation, but people PREFER that, not reality, which is more bland, and they do want that HDTV to "pop." It's a preferred aesthetic, and even movie makers and TV directors go to pains to REMOVE any banality to the look and use popping color for mood and symbolism or just plain aesthetics.
Aside from color looking "washed out," among the most ironic complaints I've heard after calibration is that viewers can see (and I've seen these and more for myself with calibrated HDTV's) the grain of the film far too often and consider it "noise" along with the contrast--YES, calibrated ideally according to specs, looks a bit too dark in some places. But there are more.
The problem with calibrations is that they are done absolutely OBJECTIVE. Yet, in music recording studios, and video editing suites and transfer facilities everywhere, they have and use all the OBJECTIVE electronic tools, but, also, make SUBJECTIVE adjustments. In other words, the music recording engineer/producer will ALWAYS use their EARS for that final verdict and SUBJECTIVELY alter what is supposed to what it ought to be according to the tool. The video editor/transfer tech, ALWAYS makes final adjustments to his/her eyes to get it to look "right." These electronic tools provide an objective base from which the best people use their ears and eyes to finish the job.
All things are a compromise, and I suspect that your calibrator--most likely doing the what he should be doing--made adjustments objectively for the best PQ which would be the case in some circumstances, and may have bypassed or turned off processing he may have found objectionable for the purposes of calibration, that your HDTV was designed to take a not so good image and clean it up and make so you could not tell the difference in the display of an EPG at 720P or 1080i source and scale it properly and enhance it, but especially something like an EPG which could be an overlay, and EPG's are the source of a lot of complaints about PQ. You may be getting it raw from the Dish box and it only rears its ugly head when the EPG is displayed, but I think one could also see other instances in real world PQ.
Yours truly, can see NO difference in the quality of the EPG on any of my high-end nor entry level HDTV's with the box set for 720P or 1080i without external processing. All but one now have some form of external processing, which I find far more beneficial than calibration, and it provides far greater control.
IMHO, TV and Movies are NOT real life. I enjoy a processed, but not over-processed (and ALL music and film and TV IS PROCESSED to alter the original image at some POINTS--plural--along the chain) green, that really isn't a true real-life green, and I feel very strongly that film grain is NOISE. Most filmmakers don't ever intend for film grain to be notices. While The League of Gentlemen very purposely WANTED that film grain to be MORE than noticeable (a mistake to do so, I personally believe, and thankfully, the 3rd Series did NOT have any of the awful film grain. Hmm, I wonder why they changed their minds?), as their goal was to make it look like one of those "B" Horror films with their poor film print quality and absolutely abominable telecine, most likely a live running film projector into a mirror/prism at the time of broadcast with generous helpings of film GRAIN. All unintended by the film makers.
Again, I think calibration, in general is actually a good thing, especially for mid to lower end TV's, if they can get more contrast out of the lower cost ones and there is a limit to the color palette on less expensive TV's, as well, but often people can see the difference there. The high end HDTV's seem to come out of the factory so well calibrated as they are, paying extra for a personal calibration borders on a waste of money, with only minimal gains, if any. So, decide on calibration wisely and check places like AV Forums to see if it is worth it for particular models.
But even a great calibration isn't the cure all nor will it provide you with the best PQ. Calibration does virtually nothing to address some of the most common and painful to look at PQ problems: mosquitos, banding, compression artifacts, any artifact in general, noise, and the list goes on if one watches more than Blu-rays, which themselves have may suffer from a lousy transfer that a calibrated HDTV will only make look WORSE. The solution there, if not your HDTV's built-in processing (but most HDTV built-in processors are pretty course and don't do near as good a job as external processing) is external processing, but that would put your back where you were BEFORE the calibration. Or, one could turn-off the external processor to allow the source to be seen with the benefit of calibration only, and turn on processing for your TV services, where even OTA's now have crappy PQ that are in dire need of processing at the home.
Just know and understand what one gets into with calibration, and its greatest strength is with Blu-ray movies where the muted real-life colors and lack of processing can enhance the film watching experience and, perhaps, draw you in more to the movie without distracting information like popping colors, etc. As for TV, I've got Anchor Bay and Marvell Qdeo doing it necessary magic (the Faroudja I had seemed to perform identical to the Anchor Bay) while my Series 6 Sammy's (the only HDTV with out external processing) built-in processor just can't kick the misquito without a noticeable compromise, and people can tell it doesn't look as good as the other HDTV's, even worse, they say, than my horrid entry level Sharp (far inferior to the Series 6 Sammy) but is now great looking, they say, via Anchor Bay compared to the non-external processed Series 6 Sammy. Everybody notices the effect of the external processing I use, but they have no idea it is being externally processed. They just think it is all the TV. They just aren't people who even know external processing exists. But I get compliments and they think their very expensive HDTV does not look as good. That makes me fell a bit better about the investment I made.
Long answer, but, no, I do not notice what you've noticed, OP. And thankfully so.
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