I want to try my hand at some landscape and long exposure photography.

I have zero practical knowledge of the filters people use and which brand to purchase. I tried one 10 stop ND filter with a bad but correctable color cast.

I do not foresee lugging the xf 16-55. It would mostly be primes I have ( all <77 mm filter threads ). I have been researching the Lee seven5 filter system.
Screw on filters are mostly solid ND. And the few GND screw on filters are not what I need.

I need the experience of forum users to advise me on which brand, type ( rectangular or screw on ), the brand and most importantly the densities that you
folks carry in your camera bags.

Any references to take long exposures for a beginner would be welcome.

I shall be most grateful for your help.
Thank you.

Best regards.