Deep Sky Objects To Scale

When thinking of deep sky objects (DSOs) - distant nebulae and star clusters within the Milky Way and even more distant galaxies - it's natural to assume that a large telescope is required to view them. In many cases this is true, where the vast sizes of these objects is trumped by the even greater distances to them. However, there are a number of DSOs - relative neighbours in cosmic terms - that occupy surprisingly large slices of our sky. The gallery below shows a number of fairly bright DSOs along with the Moon, to show their relative apparent sizes.

Some of these objects - the Pleiades, M42, the Double Cluster, the Andromeda galaxy and, from a really dark site the Triangulum galaxy - are naked eye visible, while the rest are barely too dim to make out without assistance. It's fairly well known that the Andromeda galaxy is 6 full Moons across, it's even done the rounds on Facebook, but less so that there are so many large hiding DSOs up there.

The images were taken with the same equipment - a short telephoto lens on a modded DSLR camera - and processed identically to preserve relative brightness and colour as much as possible, so that comparisons can be made between them. (The colours are not necessarily correct as they have not been scientifically calibrated, but are hopefully in the right ballpark.) They are just 2 minute exposures, snapshots in astrophotography terms, with the exception of the Moon which was exposed for a  fraction of a second. After all, it's daytime on the Moon, so taking a picture of it requires daytime camera settings.

Shooting these images was a fun way to use less than ideal conditions, taking short exposures to use the camera as an enhanced viewing device, helping me relate what I could see by eye to the deep exposures I'm more familiar with. I was able to dodge around the clouds as they swept through and pick out my targets. The starfields are also notable, the ones along the plane of the Milky Way show a far higher density and variety than those taken away from it.
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The camera used isn't more sensitive than the eye, but it has the ability to gather light over an arbitrarily long period of time. A 38 minute image of the Heart & Soul Nebulae gives more depth and detail.