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Best budget lens for the nikon z7?

For a budget lens on the Z7, I'd start with a fast 50mm prime. It's the cheapest way to get sharp portraits and low-light shots, and the guide suggests the same for a first kit: Your first camera explains why a cheap prime is worth spending on.

My picks from the Z7 list:

I'd go with the 50mm first. It's the most useful focal length for the money.

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