There are two choices to disable the default nanny function which limits image size in Wordpress to 2560px. There’s no GUI but here’s how to do it.
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High ISO Noise Reduction: CaptureOne vs DXO PhotoLab
How much of a difference can software make with high ISO images? A lot of difference it turns out.
How to restore missing WordPress Featured Image Screen Option
The issue is not in any of Settings –> Media, in Appearance, in the Customizer or in wp-config. Here’s the code to drop into functions.php.
WordPress images uploaded by client too large? try Imsanity
Imagine that someone created a plugin which would resize huge images to the maximum size used on your site.
How to get HTTPD and FTP to play well together or SEO image management nirvana
How to solve the server side permissions issues between HTTPD and FTP. Making KFM play nice with FTP.