I’ve been doing slideshows for years using a combination of Proshow Producer and Vegas. I usually do my animations in Proshow (a lot easier, especially for complex, multi-layered effects), export, and then import into Vegas, adding titles, music, and voiceover tracks. However, for fairly simple slideshows, I’ve often used Vegas only and the rendered quality is quite good. I really can’t tell the difference.
IMHO, the important thing is to resize your images before importing them into either Vegas or Proshow. A good rule of thumb seems to be to resize your images to roughly twice the vertical resolution of your output. E.g. Blu-ray is 1080, so resize your images to 2160. An exception would be if you wanted to really zoom in on only a part of the image. Since you have Lightroom, you could easily export to JPG’s with the vertical resolution of your choosing. Regardless, your results will look better using Producer or Vegas.
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