diablue

Plugin allows admin to upload custom logo for WordPress login page.
After activating the plugin, follow these steps:
<ol>
<li>Go to Settings -> Custom Login Logo</li>
<li>Click “Choose Image”</li>
<li>Select or upload your logo</li>
<li>Click Save Changes</li>
<li>Refresh the login page to see the new logo</li>
</ol>

Diablue Login Customizer

Easily add a custom logo to your WordPress login page using the built-in media uploader. Change WordPress login logo from admin panel.

Kerry Webster

Features of the Branded Login Screen plugin:
<ul>
<li>FULL SCREEN BACKGROUND IMAGE</li>
<li>USE YOUR OWN HEADER IMAGE IN PLACE OF THE WORDPRESS LOGO</li>
<li>POSITION LOGIN FORM: LEFT, CENTER OR RIGHT / TOP, MIDDLE</li>
<li>LOGIN FORM IS RESPONSIVE FOR SMALLER SCREENS</li>
<li>SCROLLING OF FORM IF OUTSIDE OF VIEWPORT</li>
<li>BACKGROUND IMAGE SIZES WITH WINDOW RESIZE</li>
<li>REPEATING BACKGROUND IMAGES SUPPORTED</li>
<li>REMOVES ALL WORDPRESS BRANDING</li>
<li>STILL UPGRADE PROOF</li>
</ul>

Branded Login Screen

Update the WordPress Login Screen to use a hi-res, full screen, resizing background image. Now completely responsive.

Diablue Login Customizer vs Branded Login Screen