Photos Slideshow

Hey Swallow07,

Welcome to Apple Support Communities.

Since the Photos app is part of the macOS, start with making sure it is up-to-date. For steps on how to do so, click here: Update macOS on Mac. Since updates include bug fixes, it may help with your issue.

If updating doesn't help or if the macOS is already up-to-date, provide us more details about the issue.

-Are the photos stored locally on the device, external device, and/or iCloud?

-Does it happen in a different user account? If you only have one, you can create a test one by following the steps here: Add a user or group on Mac.

-Does it happen in safe mode: Start up your Mac in safe mode.

This information may help you get more answers.

Take care.

Hello Sheree_P

I recognise that this thread started some time ago but I too have a similar problem. Let me walk you through my issue:

• The images (e.g. initially Sony RAW6000 × 3216) have been imported to/from Lightroom at high quality into the Photos App on my Mac-mini, still at high quality
• 16GB M1 Mac mini is using macOS Sonoma 14.4
• Apple Pro Disaply XDR
• Photos App is Version 9.0 (646.2.101)
• I've also added some iPhone images
• All individual images are crystal clear
• I can create a slideshow, use my own music and play the slideshow in Photos: the images are still very clear
• When I export the slideshow it creates a .m4v file
• I've tried at 1080p and 720p but the (lack of) quality results are similar
• The slideshow comprise 93 images that make the slideshow a 472MB file
• However, when I play the slideshow all images are blurry
• As a test when I've copied the individual files as a backup they are anything from low (iPhone) 1MB up to 60MB (from Photos / Lightroom)
• I made several versions - to get a more clearer version, and failed every time
• It's driving me crazy :-(

I've looked for help on the internet but nothing specific found, hence me reaching out to the community.

My next step perhaps is to import the iPhone images into Lightroom and create a slideshow - with the other RAW edited images - from there but this is a faff. Therefore a last resort.

Maybe there's a cloud service or other Mac App that I could try for the results I seek?

Question: why is the Photos App failiing to retain the image quality I need? Help!