APL uses, by default, an origin of 1. Having used APL extensively for probably around ten years for everything from database management to financial, mathematical, image processing and even DNA sequencing applications I would conclude that an origin of 1 is not a problem. At least it isn't for APL.
That said, APL does have a system variable known as the "index origin" that allows you to change the origin as desired when needed. The variable is called ⎕IO (pronounced "quad i o". The "⍳" operator is roughly equivalent to python's range(n) function.
With the default ⎕IO set to 1:
⍳10
1 2 3 4 5 6 7 8 9 10
a ← "This is a string"
a[1]
T
If you set it to 0:
⎕IO ← 0
⍳10
0 1 2 3 4 5 6 7 8 9
a[1]
h
You can use this to your advantage during computation. For example, to go along with your image element calculation, you could set your index origin to 0, do the math index and whatever else needs to be done with ⎕IO at 0 and then go back to 1. I found the concept to be really powerful.
That said, APL does have a system variable known as the "index origin" that allows you to change the origin as desired when needed. The variable is called ⎕IO (pronounced "quad i o". The "⍳" operator is roughly equivalent to python's range(n) function.
With the default ⎕IO set to 1:
If you set it to 0: You can use this to your advantage during computation. For example, to go along with your image element calculation, you could set your index origin to 0, do the math index and whatever else needs to be done with ⎕IO at 0 and then go back to 1. I found the concept to be really powerful.