how do I figure logrhthms on calculator other than power 0f 10

This is the short version of what CPhill is telling you

$$log_bA = \frac{logA}{logb}$$

You can use whatever base you want - I suggest base 10 or base e so that you can do it on your calculator 

how do I figure logrhthms on calculator other than power 0f 10

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Let me show you how to do this ...... 

Suppose we have log_a(b)   where "a" is the base and "b" is what we're trying to take  the log of.... (that's some bad English, isn't it??)

Exponentially, what this says is

a^x = b

Now take the "log" of both sides .....  we have

loga^x = logb

And, by a property of logs, we can bring the "x" out front

(x)loga  = logb

Solving for x gives

x = log(b)/log(a)

And "x" is just the exponent (power) that we need to "raise" "a" to in order to obtain "b"

But, that is the definition of a logarithm.

So, to find the log in any other base than 10 or "e," just divide the log of the number you're trying to find the log of by the log of the base you're using......