The images you submit in club competitions provides the club with entries for the 4Cs monthly digital competitions. The rules for sizing and naming are precise to ensure consistency among the entries.
Name your files like this: JohnDoe_GPC_NameOfImage. You should add an "A" at the end for Altered Reality, an "M" for Monochrome and a "T" for Traditional color. So the second "traditional" image would be named JohnDoe_GPC_AnotherImage_T. Don't type in "jpeg" as it will add that extension automatically when you save as a jpeg.
The maximum pixel dimension is no more than 1080 pixels vertically nor more than 1920 horizontally. The DPI setting has no effect on images to be projected, so don't worry about that. Check out the page on how to resize your image. You can link to it on the "Instructions" page.