How does TESS focus on bright nearby stars? How does the Transiting Exoplanet Survey Satellite "focus on" bright nearby stars, in contrast to the Kepler Mission's focus on dim distant stars?
I understand that the fields of view of the two missions is different, but this is a question about optics and perhaps data analysis: how can a telescope (or perhaps its data pipeline) emphasize bright nearby stars over dim distant ones. Or perhaps the question is reversed: how does Kepler exclude or ignore bright nearby ones? It's not as if the respective telescopes can literally focus on nearer or farther stars; and it's not clear to me how Kepler can avoid studying bright ones if it is studying dim ones? 
Is it simply a question of study populations: Kepler looks on a smaller patch of sky where most stars will be dim and distant (and the mission just ignores the few bright ones in its field that the more sensitive equipment can clearly see) while TESS sees (nearly) all the bright (and thus mostly near) ones (and isn't sensitive enough to see the many more dim ones)?
 A: It's all about exposure times and field of view. 
Both surveys collect data from of order 200k stars. The Kepler field of view is fixed at 1/400 of the sky. The field does not contain that many bright stars. To get good data on many stars, the Kepler telescope is relatively large and the exposure times quite long. Kepler's main science aim was to find rare, long-period, small, Earth like planets, so had to go with this kind of strategy. There are not many bright stars in Kepler's limited field of view, and the brightest can saturate the detectors.
TESS is different. It scans (eventually) the whole sky quickly, taking short exposures and monitoring any particular star non-continuously for just a few weeks or so. The short exposures and monitoring rate mean that it can only accumulate good, planet-finding data for much brighter stars than most of the Kepler planet hosts. But there are a large number of such stars spread over the whole sky. TESS data are not good enough to find (small) planets around faint stars.
TESS's main science aim is to find small planets in relatively short period orbits around bright stars. Hence the different observing strategy.
The final part of the answer is that both Kepler and TESS have a limited bandwidth for telemetry, so rather than download all the data recorded by their cameras, they do in fact "focus" on particular objects - downloading particular pixels containing data on particular stars and essentially concentrating on those where it is known that good data will be collected.
