The following is an exercise, and an indulgence, based on the new testimony clarifying the path of one of Wrigley Field's legendary home runs, the blast by Roberto Clemente on May 17, 1959, in the second game of a doubleheader. See the recent Fanpost by David Speed for details and new testimony regarding this home run.
The home run that has usually been regarded as the longest in Wrigley history was struck by Dave Kingman, then a Met, on April 14, 1976, which landed on the grounds of 3705 Kenmore. Baseball's Ultimate Power (Bill Jenkinson, 2010) a comprehensive list of the longest home runs, lists the Kingman shot at 540 feet (only Babe Ruth has longer homers in Jenkinson's listings), and the Clemente homer at 510 feet. I witnessed the Kingman home run personally, it remains one of my indelible baseball memories.
What I propose is to use the measuring tools of Photoshop to delineate, compare, and estimate the Clemente and Kingman clouts. This is meant to be fun, and perhaps instructive. In no way is it claimed to be definitive. In these days of GPS, distances to the inch could no doubt be obtained, if agreed-upon points of origin were used. But I'm going to go old school. Never thought I would write that Photoshop was "old school."
Image #1: a high resolution aerial view of Wrigley Field, as directly overhead as I could obtain, a Google Earth view from mid-2015 (note the video boards in place, and the right-field bleachers not yet complete, this is probably from May or June last year). This has the advantage of supplying linear measurements virtually free of perspective distortions. Image size of the original file: 9.5in by 9.5in, at 300ppi.
Image #2: the same, with some necessary landmarks highlighted. A: home plate. B: the footprint of the center field scoreboard, essential for estimating Clemente's trajectory. C: the site of the former gas station at the NE corner of Waveland & Sheffield, where Clemente's homer finally came to rest after bouncing. D: the footprint of the property of 3705 Kenmore, where Kingman's homer landed.
Image #3: the same, with an obvious known measurement which will be used to estimate the home run distances. E: the left field line distance is 532 pixels, thus 532 pixels will be taken to equal 355 feet. Computing the home run distances is then a matter of simple arithmetic.
Image #4: F: a projected path for the Clemente home run. The line passes just to the left of the scoreboard footprint, and ends at the front of the far curb on Waveland. As noted in the Fanpost, this splits dead center field exactly. The ball then bounced into the grounds of the gas station, which is not on a direct line with the home run path, but any number of factors could affect the bounding of the ball after landing. Path is 790 pixels, extrapolated distance 536 feet.
Image #5: G: the projected path of the Kingman home run, which was witnessed by several to have struck the near side of the front stoop at 3705 Kenmore, and then caromed back in the direction of Wrigley, where it was retrieved by a ballhawk and presented to Kingman following the game. Path is 770 pixels, extrapolated distance 522.5 feet.
Settled? Not so fast, some necessary caveats need to be addressed.
Kingman's home run can be far more precisely documented and estimated than Clemente's. Its landing place was described in detail at the time (per the newspaper accounts) and the stoop still exists in its original position. Anyone standing at the south side of the stoop could provide a location accurate to a radius of a few feet at worst.
Clemente's homer exhibits problems in specifying an exact landing spot. Even the recent testimony cited allows for considerable speculation, as the ball, according to the account, either landed at the curb or shorthopped it. The witness was some distance away at the time, and there is no defining structural landmark to aid in the exact landfall identification. The projected path I provided in Image #4 (F), in fact gives all possible advantages to the proposed landfall; it passes the scoreboard barely to the left, and assumes a landfall at the curb itself. The oft-used "just to the left of the scoreboard" has its own problems with precision. The slightest alteration in locating this landfall can make all the difference to the comparison.
Image #6: To give a final illustration of this problem, note H: a projected path for Clemente's home run that passes just to the left, lands at the curb, and results in a distance identical to Kingman's (i.e., 770 pixels = 522 ft). It fits the existing testimonies as well as F does, the difference is a matter of 2.0 degrees. A further degree to the left, which itself would be well within the given descriptions, and Kingman remains on top.
Conclusion: given the margins of error inherent in measurement, testimony, and precision, I'll call it a wash. Give 'em both a trophy.
Hope this amused, many thanks for all attention. Remember, this was all for fun.