Different image size of first image in series

[DaBrownCO]

I'm shooting a series of images to be stacked for noise reduction in Starry Landscape Stacker. The image size of all images except the first is 5304x7952 pixels. The first image is 5304x7950. This happens numerous times. 

I am not doing anything different.

Please help.

David

[DaBrownCO]

Edit: The first is 5304x7952 and all others are 5304x7950.