Please make sure to use the images of the following sizes (in px).

Halcyon Slider:  1400 X 500

Halcyon Slider Thumb: 160 X 90

Halcyon Featured Post: 360 X 290

Halcyon Recent Post: 360 X 160

Halcyon Widget Post: 320 X 320

Halcyon With Sidebar: 750 X 450

Halcyon Without Sidebar: 1170 X 450

Halcyon Schema: 600 X 60