How To Maximize Your Photo Slideshow Quality on External Displays [TUTORIAL]
By Werner Ruotsalainen
This article explains how you can output still images to your external display (TV, projector etc.) from your iDevice and what you should do to maximize quality. While some of the material requires advanced knowledge (including having read my previous multimedia-specific articles), the “All in All” section at the bottom is digestable for beginners (at least I hope it is).
Apple's stock image slideshow implementation output is, unfortunately, half-hearted. (iDevices utilize the native TV output while playing slideshows. Apart from Retina iPads, it is the only way of making full use of the more advanced output types, namely, HDMI and VGA.)