yes you can do it with eloquent, here is a simple example:

$post = new Post();
$post->title='nice title';
$post->save(); //saving the post will set the id on this post model.
for($i = 1; $i <= $numberOfImages; $i++)
{
    $image = new Image();
    $image->path = 'path you want to set';
    $post->images()->save($image); // will save the image for the post.
}

Is this also performance wise OK? Its doin a lot of queries right now? I mean, on insert with multiple records is better than a query for each record, right?

Alternatively, to reduce queries you can insert multiple records like :

Image::insert([
	[
	 'path'=>'some path',
	 'post_id'=>$post->id
	 ],
	 [
	 'path'=>'another path',
	 'post_id'=>$post->id
	 ]
	 ...
	 ...
	]);