Specifically, what happens if we change this to something like 見ると分かる、見たら分かる、見るなら分かる. Intuition tells me the first is fine, the second is weird, and the third is very weird.
Translated, everything (〜と、〜たら、〜ば) is "if", but actually all japanese conditionals have an inherent nuance. Some nuances overlap, so in some cases they are effectively the same, but in some cases they don't.
〜と usually expresses a logical/natural result because it's constant, repeatable.
eg: ボタンを押すと機械がオンになる。 -> if you press the button, the machine turns on.
〜と is also used to describe habits. More akin to "when" than "if".
eg: 毎日起きると、窓を開く。 -> I open the window everyday when I wake up.
Another use of 〜と is to describe things that simply happened after the first part. Also akin to "when" rather than "if"
eg: 昨日学校に行くと、誰もいなかった。祝日だと忘れた！ -> When I went to school yesterday, there was nobody. I forgot it was holiday!
〜たら can be used in this same fashion (to describe things that simply happened after)
昨日学校に行ったら、誰もいなかった。祝日だと忘れた！ (same meaning)
〜ば is to describe things that are the common outcome, and using it sounds kinda proverb-ish.
eg: 練習すれば、うまくなる -> If you practice, you become good. (But proverb-ish: He who practices, good becomes. or whatever haha)
It's pretty common that people that practice get better, but by no means it's written in stone. Which brings us to the next nuance, related to your sentence.
〜ば is used for hypotheticals. What is considered hypothetical is very subjective, it often depends on how the speaker perceives the condition to be.
An easy example is:
明日雨が降れば、試合が中止になる。(If it rains tomorrow, the match will be cancelled)
You can't know whether it will rain or not for sure. In english, an announcement would likely be worded "in the event of rain, the match will be cancelled" for the same reason, it's an hypothetical situation.
So the japanese speaker decides whether to use 〜ば or not, in subjective fashion.
A common phrasing for proposing marriage is "私で良ければ、結婚してください".
"If I am good (enough for you), marry me please"
Why 〜ば？ Because the person proposing can't know for sure if their partner consider them "good enough" or not.
So -from the speaker point of view- it's an hypothetical situation.
This is exactly what happens in your sentence:
If you look (In the hypothetical case that you look) you would know.
The speaker can't know if the listener had looked or not nor if they will look or not.
Hence the usage of 〜ば。
BUT! This usage is kind of sarcastic. Which is pretty much the most common usage of 見ればわかる. It sounds hypothetical and proverb-ish... but it's just implying "why don't you just look?".
A somewhat decent summary of conditional nuances and common usage can be found in the following link:
Sadly it's only in japanese.