Straightening in photoshop

[MJD]

hoping this is a concise place to ask. 

I saw you reference this in a response to a levels submission 
 

https://www.damiensymonds.net/2010/01/straightening-horizons.html

 

is this something I should be incorporating before I start my levels as well? (If applicable) 

likewise, is this where you would make an adjustment if there was some lens distortion? Can you link me to something on that? 
 

I have a photo waiting your approval in Raw that I’d also like you to verify if you see some lens distortion and how and when to address. (The bells bell)

[MJD]

https://www.damiensymonds.net/2014/03/distortion-or-perspective-correction.html
 

here, yes? 
 

so, should I do that first before levels? 

[Damien Symonds]

Yep, it has to be the first step in PS.

https://www.damiensymonds.net/2015/07/order-of-layers-for-complex-pixel-edits.html