Is there a way to prevent a photo conversion from leaving some stitches blank or empty when it should be white? Or maybe a way to highlight those empty stitches to make them easier to find? It should be a full coverage piece.
I've never seen blank stitches in a conversion. I've had to MAKE them by removing colors. If you have blank where you want white in the background, there's an easy way to do it. You may have to look for blank stitches elsewhere to put them in manually but for broad areas - just "paint". Select your color (white from what you say), select the fill/paint option and click in one of the open areas.
To find the blank areas elsewhere, define the "fabric" color to be really really bright and as different from your color palette as possible. They will show up better and you can change them.
I'm doing some complex conversions and there are many stitches coming up blank. That's a great idea to do the fabric colour change to help find them. Thanks for the tip! I'm also doing a Floss Usage total to make sure it tallies with the h x w calculations to make sure I got them all. Thank you for the help!