Thanks Guys for the different thoughts.

Our images have to have maximum of 1024 width and max of 768 height and max 500kb.
So if I have a portrait of say 1536 width by 3072 height this will be resized to 384 x 768 to retain proportion. NOT cropped as then the composition will be lost.
I normally resize image to say max width of 1024 or max height of 768 as required by the rules and the proportion of the file. Resizing to 1024 x 1024 IS NOT allowed and rejected by the judges.
This means entrants putting in portrait style entries are greatly reducing the image compared to landscape entries. Some of us now are shooting / composing square format say 3000 x 3000 to gain more screen size after resizing to 768 x 768.
I will try the save for web method and see how it goes.
One day the rules may change to say HD size that will help when / if we get a HD projector

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