Full Size Binoculars:
Taking full sized 10×42 or 8×42 binoculars on safari is not an ideal choice for many people and I usually recommend taking mid-sized or even a compacts instead. This is mainly because if you are going on holiday it makes sense to keep the size and weight of your luggage down to a minimum. On top of this, if you are planing on a walking safari and you also want to take your camera as well, a smaller pair of binoculars is just that much easier to carry.
However smaller binoculars do have their downsides. The biggest being that fact that because they have smaller objective lenses, they let in less light and therefore don’t perform as well, especially in low light conditions as comparable binoculars with larger lenses.
Low Light… For the most part light will not be a problem, but remember most of the safaris that you go on will leave very early in the morning (sometimes at or just before sunrise) and then late on in the afternoon. This is because birds and larger animals are far more active at this time. But it is also when lighting is not optimum. Now, I am not saying that compact binoculars will not work, in fact I still suggest that for many people they are the ideal binoculars for safaris, but for those who want the best possible image and who are not so worried about size and weight, then a quality full sized binocular is the way to go.