A week ago today I set 17 eggs from my GLW and black Jersey Giant in the incubator (LG still air). The eggs are all brown-shelled, some fairly large. I have followed candeling directions from the sticky here, but I really have no idea what - if anything - I'm seeing. With my little LED flashlight, in a dark room, I can see the veins through my fingers, but not through my hands (just to give you an idea of the strength of the light). So, the first time I tried candeling (4 days ago), I could not see anything - EXCEPT the air cell, which I could see on all of the eggs distinctly enough that I could trace their outlines in pencil on the eggs. Which is what I did. Otherwise, all I saw was a shadow which I assume could be yoke. Just for fun, I candeled a fresh egg from one of these same hens, and although I did see the air cell on the new egg, I didn't see any of the shadow that on the other eggs I presumed to be yolk. This morning (day 7) I candeled two of the eggs, and still couldn't decipher anything - except, again, the air cell. In each instance, the air cell is clearly slightly larger than prior (i.e., extends beyond my tracing of 4 days ago). Is it possible to assess the fertility/viability/status of the eggs just via the air cell if I can't see anything specific other than that?