My first clutch is the same way. I was a bit worried when I candled around day 50?-not sure on exact day-and the eggs looked about 1/4 full. I figured they'd be at least 1/2 full by that time. The eggs were still nice and plump, had nice veins, and wiggly worms! I could make out the morphs inside if they pressed against the egg just right.
Its now day 60 and they've grown a good bit. Though... They still haven't pipped
Good luck! It may just take a bit longer for your guys and gals as well.
Sorry not sure how to edit a post. I just wanted to share that one in my clutch just pipped, so we cut the other eggs. We candled them first. They still appeared less than 1/2full, but the babies are big! I wouldn't worry.