ED Spotting Scopes

If you have been researching spotting scopes, you have probably come across the term “ED” more than once. It appears in product names, gets highlighted in spec sheets and is regularly mentioned as a reason to spend a little more.

The obvious question is whether an ED spotting scope is actually any different from a standard model.

What Does ED Mean?

ED stands for Extra Low Dispersion. It refers to a special type of glass used in the scope’s optical system.

Its job is to reduce colour fringing, also known as chromatic aberration. This is the unwanted purple, blue or green outline that can appear around high contrast subjects. This is noticeable when you are watching a bird against a bright sky.

ED glass is designed to minimise that effect.

Why Does ED Glass Matter?

The difference is easiest to see when you are picking out fine detail. A bird’s plumage, the texture of an animal’s coat or the contours of a distant hillside can all appear sharper and more defined through ED glass.

Colours also tend to look more natural, because the light is being better controlled as it passes through the optical system. How obvious this is depends on what you are looking at and the conditions you are in.

Will Every User Notice The Difference?

Not always, and that is worth being honest about. Someone coming from an older or entry level scope may notice the improvement straight away. Others might only pick it up when comparing two scopes side by side. Higher magnifications and detailed subjects are where ED glass’s advantages are more obvious.

Are ED Spotting Scopes Only Found In Premium Models?

That used to be the case but it is much less true now. ED glass has worked its way into mid range spotting scopes across a wide range of price points. This makes the technology more accessible than before.

Premium models still benefit from more advanced optical systems overall but ED glass alone is no longer a feature reserved for top end products.