FX format vs DX format DSLRs
FX format vs DX format DSLRs
This site is about looking at the performance of macro-capable lenses on Nikon DSLRs with two different sensor sizes, the FX and DX format.
This site is about looking at the performance of macro-capable lenses on Nikon DSLRs with two different sensor sizes, the FX and DX format.
DX-based DSLRs are on the whole cheaper and the range includes many low cost entry-level models. There is a very important reason for the macro-shooter to consider having a DX format DSLR - depth of field (DoF). Most people are aware that the very small sensor on smart phones gives a very big depth-of-field(DoF). More recently frame stacking has been introduced to merge a number of frames of different focus to create a bigger DoF. To achieve this everything needs to be very stationary which is difficult with hand held field photography. For those wanting to shoot single sharp frames hand-held, DX format cameras have an advantage in DoF over larger sensor FX cameras. The figure below shows the centre resolution of macro lens (in this case a Micro-NIKKOR 105mm) when the lens to target distance is varied on either side of the optimal focus point.
DX-based DSLRs are on the whole cheaper and the range includes many low cost entry-level models. There is a very important reason for the macro-shooter to consider having a DX format DSLR - depth of field (DoF). Most people are aware that the very small sensor on smart phones gives a very big depth-of-field(DoF). More recently frame stacking has been introduced to merge a number of frames of different focus to create a bigger DoF. To achieve this everything needs to be very stationary which is difficult with hand held field photography. For those wanting to shoot single sharp frames hand-held, DX format cameras have an advantage in DoF over larger sensor FX cameras. The figure below shows the centre resolution of macro lens (in this case a Micro-NIKKOR 105mm) when the lens to target distance is varied on either side of the optimal focus point.
With the D500 (DX sensor) four of the frames have a resolution above 2500 LW/PH whereas on the D800 (FX sensor) only two frames have a resolution above 2500 LW/PH. The subject (target) is exactly the same in both cases
With the D500 (DX sensor) four of the frames have a resolution above 2500 LW/PH whereas on the D800 (FX sensor) only two frames have a resolution above 2500 LW/PH. The subject (target) is exactly the same in both cases
Why use the D500 and D800 for most of the Analysis?
Why use the D500 and D800 for most of the Analysis?
The absolute number of pixels in the sensors of cameras used is not important for the lens analysis on this site. It is the relative performance of the lenses at different apertures that is the subject of interest. This means that the optimal apertures for macro work will be applicable to a range of DX- and FX- format cameras. The ultimate resolution achieved will depend upon the lens/aperture/sensor combination used. It is generally held that most lenses perform best with the aperture stopped down by 2 stops from fully open. This would mean that a lens with a maximum aperture of f/2.8 would most likely perform optically at it best at f/5.6. If you peruse the data on this site you will see that this is quite often true, especially when using the lenses at low magnification (or reproduction ratio). However in other situations stopping down a little more gives better results for macro when DoF and edge-to-edge sharpness is important.
The absolute number of pixels in the sensors of cameras used is not important for the lens analysis on this site. It is the relative performance of the lenses at different apertures that is the subject of interest. This means that the optimal apertures for macro work will be applicable to a range of DX- and FX- format cameras. The ultimate resolution achieved will depend upon the lens/aperture/sensor combination used. It is generally held that most lenses perform best with the aperture stopped down by 2 stops from fully open. This would mean that a lens with a maximum aperture of f/2.8 would most likely perform optically at it best at f/5.6. If you peruse the data on this site you will see that this is quite often true, especially when using the lenses at low magnification (or reproduction ratio). However in other situations stopping down a little more gives better results for macro when DoF and edge-to-edge sharpness is important.