TOWER GROVE — Like anybody else who saw Albert Pujols’ bolt to the fourth story of San Diego’s Western Metal Supply Co. building, Greg Rybarczyk felt it had to be a mammoth blast, one with the distance to match the reaction of the players.

But Rybarczyk knew better.

“When I saw that ball hit, I thoguht it was a huge homer, just like everyone else — something about the angle off the bat, the speed of the swing, it just looked like a real bomb,” Rybarczyk said. “But when I went to look at, surprisingly it turned out to be more of a regular fly ball than a screaming liner.”

Rybarczyk runs Hit Tracker Online, a Web site dedicated to calculating “how far it really went … “ Rybarczyk uses his own maps of the ballparks, exit speeds and gobs of other data to track each home run hit in the majors and determine the true distance — not the ballpark estimated distance — of the home run.

At many ballparks around baseball, the act of estimating distances for home runs has been more and more exact. When the new Busch Stadium opened, a couple members of the Cardinals staff went out with a yard stick to take measurements they used to create a detailed  distance map for home runs hit at the ballpark. Most ballparks have three numbers for each section of the ballpark — one for each kind of home run: “screaming liner”, standard homer and high rainbow.

San Diego announced that Pujols’ first home run Monday traveled 405 feet.

It was described repeatedly, including by me, as a conservative estimate.

Those descriptions are incorrect. Rybarczyk did his calculations and found out …

The homer traveled 405 feet.

“It is a visually deceiving homer because it impacted so high up in the air - those tend to look longer for that reason,” Rybarczyk wrote me in an email explaining the measurement. “But the Western Metal Supply building is actually very close to home plate: the corner (which is also the foul “pole”) is marked at 334 feet, and the patios are actually as close as 328 feet, hanging over the field in fact. Pujols’ homer impacted about 58 feet above field level, 356 feet from home plate, after 4.28 seconds in the air. Hit Tracker projects it to 405 feet, and figures it came off the bat at just under 109 mph.”

Rybarczyk offers the following chart on his Web site:

The time it took Pujols’ homer to leave the ball is an important part of the calculation, and Rybarczyk mentions that 4.28 seconds to land “is a fairly long time.” Milwaukee’s Ryan Braun hit a blast last week at Fenway Park that took 2.78 seconds to land. He also said the new ballparks and their Crawford Boxes and Big Mac Lands and, yes, Wester Metal Supply Cos. cause a visual trick on the distance of home runs.

The longest homer hit at Petco Park was by Andruw Jones, and it went 463 feet, but because it traveled to left-center field without the fanfare, without the ballpark prop, it “did not garner nearly the attention that Pujols’ homer did,” Rybarczyk wrote.

“I suspect we all expect Pujols’ homers to be longer, also, having seen quite a few impressive shots,” he wrote in an email. ”Also, many of the newer parks have tall objects close to home plate (the WMS building in SD, the upper deck in RF at Citizens Bank Park, actually even Big Mac Land is very close to home plate laterally), so it tricks our eyes when a ball flies high and into or over one of those objects. So, don’t feel bad, I think we all are susceptible to that optical illusion, which is why it’s good to have something like Hit Tracker to objectively figure the distances out …”

There is a scatter plot of all of Pujols’ home runs this season available at his own page on Hit Tracker. And that bolt in San Diego of Justin Germano actually lowered his “true distance” average for home runs this season. The scatter plot allows you to go back a few years — which, when it comes to Pujols’ homers, obviously means going back to October 2005.

For the record, Pujols homer off Brad Lidge — you know the one — left the bat at 119.1 mph, had an apex of 113 feet and traveled a “true distance” of … 455 feet.

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