Can't make my mind up on these 2

[Lord Alibaski]

I need a wider lens for my a6400 I currently have these 2

Sony E 18-135mm F3.5-5.6 OSS
Sony E 70-350mm F4.5-6.3 G OSS

I'm keeping the 70-350 but wanting a lens that can give me a little more light and wider angle than the 18-135 which I might sell on to fund the new lens if the wife let's me keep it I might as well just keep it.

I am leaning more towards the Sony mainly because it's F1.4 will there be much difference in how much view between these 2 lenses I'm so confused.

Sigma 10-18mm F2.8 DC DN C vs Sony E 15mm F1.4 G

I mainly want to use it when visiting certain castles and gardens in Scotland and if I'm lucky the aurora borealis.

Thanks for any help and advice.

 

[Lord Alibaski]

Thanks for the ideas everyone will have a deep look into that Samyang see if I can hire one out for a few days see what it's like.