"I have now had the thumbnails created with 1:1 (only for some images) so I can see the quality very well, but it takes much longer to import images and the catalog increases very much.
Is also not my wish.
I don't want any thumbnails but I want Lightroom to access the images directly.
Isn't there a setting where you can tell Lightroom not to work with thumbnails at all?"
I'm not sure what you mean by thumbnails. When you import image files in LrC Import module you can specify the preview size. I suggest using the 'Standard' setting, which should speed up your import if you were using the 1:1 setting.
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