Using Optical weights in other sizes

[Verism]

Hi,

I'm working on a project for a client with a limited budget, meaning that I'm pretty much limited to free/cheap fonts. Fortunately, I've come across a great variable font "Literata" from Paratype, with axes for both weight and optical size. However, I really like how the lower optical weights look at larger sizes; in my opinion it works really well for titles, and has just the right sort of texture and feel that I'm looking for. 

That being said, I can't help but wonder if I'm committing some heinous typographic crime by using 7pt optical size at 48pt+... Is this something that you just don't do, or should I not concern myself with the numbers and just go with what feels right?

Thanks

[Ralf Herrmann]

31 minutes ago, Verism said:

wonder if I'm committing some heinous typographic crime by using 7pt optical size at 48pt+... 

I see no problem with that. The other way around would be highly problematic, but using a more sturdy design in larger sizes – there is nothing wrong with that. 

[Richard Hunt]

As Walter Tracy writes in Letters of Credit, "text types when enlarged can be used for headings, display types, if reduced, cannot be used for text setting."