In the past week I've noticed a problem in LR5.6. My native Canon files are 5760 pixels on the long side and show as such in the Library metadata module and with the Mac Finder. But in Develop they don't zoom to the same extent and on Export are outputted at 2560 pixels despite leaving the 'resize' box unchecked. I can specify an export size of 5760 but the resulting files are distinctly soft from apparent upsizing. I've reinstalled 5.5 and 5.4 to investigate the problem despite not being aware of it prior to 5.6. It's there with them too now.
I import through LR and the problem exists with both files converted to DNG and not.
On MAC 10.9.4 Any thoughts appreciated. Thanks
This is my guess
You have created smart previews, and you are performing the export without the actual photos on a drive that is connected.
The drive is connected but I will check if I've created smart previews. Thanks. Will let you know.
Yes you were right. Many thanks.
Didn't even realise I'd made Smart Previews. Don't even know what they are for.