Is the Nikon d3400 the best dslr camera for stills that costs around £400
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Is the Nikon d3400 the best dslr camera for stills that costs around £400 - 1
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The Canon 1300D is marginally cheaper which may leave you a few ££ for other things. It depends what you want to do. If you need more fps, or wider ISO then get the Nikon. If the camera Wi-Fi is useful then get the Canon.
The Nikon has a better battery life and is 24 megapixels vs 18 megapixels, but more pixels don't mean better pictures.
At that level of consumer camera there isn't a huge difference in terms of the photos they will take, and in the grand scheme of things it is the photographer who has the biggest impact on the photo.
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See if you can track down a Pentax K-50 - which will blow it out of the water.
Of course, I live in Scotland, where the K-50's weather-sealing is a VERY good idea.