gistfile1.rb

class Photo < ActiveRecord::Base
  belongs_to :user
  belongs_to :blog :through => :user
  has_attached_file :image,
                    :storage => :s3,
                    :styles => {
                      :large => "900x600",
                      :medium => "500x500",
                      :small => "240x240",
                      :square => "100x100#"}
end