Does DX/crop mode on a full-frame camera reduce low-light performance compared with cropping later?
Asked 4/1/2020
1 views
2 answers
0
If I set a full-frame camera such as the Nikon D850 to DX/crop mode, does that hurt image quality or high-ISO/low-light performance compared with shooting full frame and cropping the image later to the same field of view? I'm only asking about image quality and noise, not the composition flexibility of cropping in post.
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
6y ago
2 Answers
4
No, there is no difference between crop mode or cropping in post.
Pretty much every image characteristic comes down to light per area. If you record the subject the same size (with the same exposure settings) on a larger sensor, it is recorded physically larger. So you get more area of the same light (larger area/same density). And when output at the same display size that becomes more light w/in the same area (same area/greater density)... i.e. more light/area.
The crop/smaller format will show more noise at any given display size simply because it contains less light, and the displayed image has less light density per image area.
In fact, there's no real/significant difference compared to using a TC or a variable aperture zoom lens instead either... although variable aperture zoom lenses don't typically loose light at a linear 1:1 rate.
Originally by user70370. Source · Licensed CC BY-SA 4.0
user70370
6y ago
0
Generated from our catalog & community — verify before relying on it.
No. If the framing, lens, exposure, and final crop are the same, using in-camera crop mode and cropping later give essentially the same image quality and noise.
Crop mode does not make the sensor itself noisier; it just records a smaller central portion of the sensor. If you would have cropped to that same area afterward, the result is effectively the same at the pixel level.
Why people say full frame is better in low light: a full-frame advantage appears when you actually use the larger sensor area for the same final image size. A larger capture area gathers more total light, which improves noise when images are compared at the same output size. But once you restrict the full-frame camera to a DX-sized area, you give up most of that area advantage, so performance becomes similar to a comparable DX capture.
So:
- full frame used as full frame: better low-light potential at equal output size
- full frame in crop mode: similar to cropping later
- cropped full-frame image vs native DX image: often broadly similar, depending on pixel count and sensor design
Recommended products
UniqueBot
AI6y ago
Your Answer
Related Questions
What do I lose by using DX crop mode on a Nikon D810 with an FX 70-200mm lens?
Can Nikon FX bodies use DX lenses in crop mode?
Does a lower-resolution sensor have better low-light performance if sensor size is the same?
Should I choose a Nikon D800 or Nikon Df as my first FX body if the D800 costs less?
Should I buy a 35mm f/1.4 or f/1.8 as my first fast prime for a Nikon DX camera?