The transfer itself is not reducing image quality. If you copy the original photo files from your Galaxy phone to your PC, the image data stays the same.

What you’re seeing is most likely a display difference: phone screens are often tuned to look brighter, punchier, and more saturated, while a PC monitor may be set up very differently. In other words, the screens are showing the same file in different ways.

For editing in Photoshop, transfer the original files directly rather than screenshots or compressed exports. If the files are copied intact, there is no quality loss from the transfer process.

If you want what you see on the PC to be more trustworthy, focus on monitor setup and calibration rather than the transfer method. A properly calibrated monitor is much better for accurate editing than a typical phone display.