Thumbnail generation for image gallery

Hi,
I want create an image gallery with quite many images (with names and descriptions) with pagebuilder.
The problem is thumbnails are not generated and page weight is growing fast.
Is there a way to generate automaticly thumbnail with pagebuilder? Or do i have to create manually thumbs (not using auto link)?
Another solution would probably be MediaboxCK but in that case i'll loose the benefit of building my page with PBCK...any advice?
Thanks!

Hi
you can use a plugin to resize your images, for example
extensions.joomla.org/extension/eir-easy-image-resizer/

but you can not use the auto link because you won't see the big image ...
there is no option for that into Page Builder CK
CEd

Thanks Ced,
That's the solution i wanted to avoid but that's Ok i'll do it manually.
Maybe a good idea for the future to implement this (using mediabox in PBCK)
Thanks again, your extensions are awesome!

thank you
for the auto thumb, this is possible, but the result is not really great without using custom services and the best is really to use your own images already made by you with the correct dimensions. There are some tools like IceCream Resizer that allows you to resize your images quickly

Thanks!
My true problem is i'm not the one who 'll administrate the website and i'm afraid that the person in charge will be lost if there are to much steps to post images with correct size for thumbs and original.
I'll check Icecream to see if it's easy enough for a beginner webmaster.
Thanks again!