Well, you shouldn’t be. While it is true that full frame sensors are better at high ISO imaging, you can get decent images with cropped sensors if you can get some control over your noise reduction. You can learn a little about noise in this article.
The first step is to shoot in RAW so you can manage your own noise reduction and sharpening, which work hand-in-hand. As you increase your noise reduction your image will need some extra sharpening. While shooting in JPEG lets the camera take care of it all for you, you can get much better results if you do it yourself.
Consider this image of a cormorant made with a cropped sensor camera. I was shooting an f4 lens and using a 2X teleconverter, so my fastest aperture was f8 which is pretty slow compared to most lenses. I had been using the built in noise reduction and sharpening found in the Adobe Camera RAW editor but I have since switched to Noiseware which gives me much better performance.
You can see in the data listed at the bottom that I was shooting at a whopping 12800 ISO! But after proper noise reduction and sharpening I ended up with a very satisfactory image.
While I prefer to shoot at lower ISO values, I don’t worry too much about it. I know I’ll have to lose a little bit of detail in the end but I can still come out with a nice image after using the proper tools.
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