Ideal image size on EPZ using a 4K monitor

Hi all, I recently about 3 months ago was forced to upgrade monitor as the Asus 1920 x 1200 packed in. I went for a Lenovo Think Vision 4K one with 3840 x 2160 screen and I run it at that resolution too. I upgraded the graphics card too to support the 4K monitor.
Since the upgrade I note when I post an image on EPZ or other platforms for that matter the image is just not sharp, I know they are sharp when I save them as my workflow hasnt changed. I have always resized my images to 2048px on the long edge and they have always been sharp, as sharp as on my monitor after editing, however even though I still resize at 2048px they are always appear stretched and then thats were the sharpness just falls off, Is there an answer to my issue and has anyone else had issues when going from HD to 4K? TIA Phil
Since the upgrade I note when I post an image on EPZ or other platforms for that matter the image is just not sharp, I know they are sharp when I save them as my workflow hasnt changed. I have always resized my images to 2048px on the long edge and they have always been sharp, as sharp as on my monitor after editing, however even though I still resize at 2048px they are always appear stretched and then thats were the sharpness just falls off, Is there an answer to my issue and has anyone else had issues when going from HD to 4K? TIA Phil

For uploading to ePz the following criteria should always apply in order to get the best result:
Do not resize - upload the largest jpeg file you have. The site's logarithms take care of sizing for various platforms.
Always apply sharpening before uploading - use whatever is a part of your normal workflow.
Always convert to (not assign) sRGB before uploading.
Do not resize - upload the largest jpeg file you have. The site's logarithms take care of sizing for various platforms.
Always apply sharpening before uploading - use whatever is a part of your normal workflow.
Always convert to (not assign) sRGB before uploading.

Quote:For uploading to ePz the following criteria should always apply in order to get the best result:
Do not resize - upload the largest jpeg file you have. The site's logarithms take care of sizing for various platforms.
Always apply sharpening before uploading - use whatever is a part of your normal workflow.
Always convert to (not assign) sRGB before uploading.
Hi Malc, I have uploaded two images full size and 2048 on long edge, both appear the same on my pc, does anyone see a difference on theres? ta Phil

Of the two images - difficult to tell a difference when viewing in the forum, but when opened to full screen, the 'full size' image is definitely sharper.
For reference, I am running an a 2k/1080p monitor - so when I am viewing the '2048' image at full screen size, this is near enough 100% magnification.
One thing I have noted for some time, is that viewing web images at 100% always looks a bit ropey. I find I get a better result when I resize and sharpen for double the resolution the images is displayed at on the screen. For example the Gallery on EPZ seems to render my images at 1200 to 1500 pixels wide on my screen, so sizing the images to 2048 and sharpening works a treat -> on my screen. How it looks on a 4k screen I have no idea!
(someone please tell!)
For reference, I am running an a 2k/1080p monitor - so when I am viewing the '2048' image at full screen size, this is near enough 100% magnification.
One thing I have noted for some time, is that viewing web images at 100% always looks a bit ropey. I find I get a better result when I resize and sharpen for double the resolution the images is displayed at on the screen. For example the Gallery on EPZ seems to render my images at 1200 to 1500 pixels wide on my screen, so sizing the images to 2048 and sharpening works a treat -> on my screen. How it looks on a 4k screen I have no idea!
(someone please tell!)