Not enough players appreciate how much better a "down the line" view is for making a line call. When ppl talk of others' bad line calls they more often make no mention of the particular view the line caller had, as compared to the questioners/complainers view. Too often the partner of a serve receiver calls the serve out (on the serve baseline) and the serve receiver overrules him and says it's in, or the opponents verbally complain. The reason the latter complain+overrule is more often because they're looking across the line and not down the line, and are therefore in no position to make a close but accurate line call on the serve base line. The USTA Code assigns responsibility for this call to the receiver's partner for good reason. And tournaments hire TEN line judges to make calls looking down (not across) each relevant line, rather than having just a couple judges make line calls all over the court, regardless of their view.
@Kevind
It’s actually not as straightforward as you might think. The RP will often have the best perspective —because they are looking DTL.
However, if the RP is turning their head or moving their eyes
as the ball is bouncing, their ability to make an accurate call is extremely poor. The SP and other players on the court do not usually need to turn their head to make this call.
If the RP is tracking the ball all the way from the server’s racquet to its bounce location, they are probably moving their head or eyes as the ball is bouncing — this is a serious mistake that players often make. Certified linespersons are taught to STOP following the ball and, instead, fixate on the line (keeping the head still) any time they see that ball appears to be headed toward the line they are calling. Studies have shown that line callers who are trying to track the ball and are moving their head or eyes as the ball is bouncing will make poor calls a high % of the time.
Those who make line calls
must get their eyes to the line BEFORE the ball bounces so that their head & eyes are “quiet” (not moving). This is what certified linespersons are trained to do.
The other issue that an RP might encounter is a
proximity problem. They may be too close to the bounce location in some situations. This would cause the ball to traverse their field of vision too quickly for their
smooth pursuit tracking to keep up. This often happens when the RP is standing relatively close to the line they are calling. Or it happens when the ball bounces fairly close to the inside corner. In this case, the RP might be a few feet (or 1 meter) from the bounce location.
Note that official linespersons are never this close to the bounce / line they are calling. No close proximity in this case. The visual tracking system of these linespersons should easily be able to picking up ball and its motion if it bounces close to the part of the line they are fixated on.
