You need a brighter light. Some of the powerful LED flashlights are extremely bright, and inexpensive. We have a less than $20 Dorcy flashlight which works well on my brown eggs. Funny thing is, it doesn't work so well on a blue colored egg, probably cuz the color of the light is close to the same color as the egg.
Olive eggs are the most impossible color to candle! You not only have the blue/green base color but then you have a layer of that dark brown over that.
I agree - get a brighter light and only candle when it's dark out. You may not be able to see really defined things like you would in a white egg, but you will be able to tell if something is in there.
Its funny, I can see in the olive eggs (with this flashlight) fairly well, it is the gorgeous blue egg which I'm doing good to see the aircell with. And the blue egg isn't very dark - I'd expect it to be the easiest egg to see into. This is also my first batch of easter eggs.
and I totally agree with the dark comment. Makes a huge difference!
I use a mag light...one of the bigger ones that takes 4 or 5 batteries (because that is what I have handy). I was able to candle Maron eggs just fine...I had some trouble with my duck eggs...couldn't see lots of movement or anything, but could see enough to know that something was growing in there. I have my incubator set up in my basement, so I go down there in the dark to candle. The least amount of "other" light that is around the better...
My mom used to use one of those old film strip projectors that she got from a school that was going to throw them out (this was years ago). That worked really well! If you can get your hands on one of them, or a mag light, that would probably do the trick for you!
Try marans, penedesenca or welsummer eggs. If you can see anything in them it will probably only be the air sac, which helps.
I can't afford the kind that will look into these eggs so I don't bother candling.
I have 8 day old brown (ISA Brown/Rhode Island Red) eggs that I am wanting to candle. When I look at them I can see small veins, but nothing else. Looking online, it says I should be seeing the eye, and small spine of an embryo.