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Main
Model
Price
Advantages
SENSOR Effective pixels: 24 megapixels
SENSOR Max resolution: 6000 x 4000
SENSOR Sensor photo detectors: 25 megapixels
IMAGE ISO: ISO 100 – 6400, Lo-1 (ISO 50), Hi-1 (ISO 12,800), Hi-2 (ISO 25,600)
IMAGE Boosted ISO (maximum): 25600
PHOTOGRAPHY FEATURES Maximum shutter speed: 1/8000 sec
PHOTOGRAPHY FEATURES Continuous drive: 6.0 fps
SCREEN / VIEWFINDER Screen size: 3.2″
SCREEN / VIEWFINDER Screen dots: 1,228,800
VIDEOGRAPHY FEATURES Resolutions: 1920 x 1080 (60, 50, 25, 24 fps), 1280 x 720 (60, 50 fps), 640 x 424 (30, 24 fps)
VIDEOGRAPHY FEATURES Microphone: Stereo
OPTICS & FOCUS Number of focus points: 51
PHYSICAL Environmentally sealed: Yes (Water and dust resistant)
PHYSICAL Battery Life (CIPA): 950
Main
Model
Price
Advantages
SENSOR Sensor size: APS-C (23.6 x 15.8 mm)
PHOTOGRAPHY FEATURES Flash range: 17.00 m (at ISO 100)
PHYSICAL Weight (inc. batteries): 703 g (1.55 lb / 24.80 oz)
CONNECTIVITY Wireless: Eye-Fi Connected
Summary
The D7100 highest resolution of 6000 x 4000 pixels (24 megapixels) is better in comparison with the Nikon D90 maximum resolution of 4288 x 2848 pixels (12 megapixels). The Nikon D90 is equipped with larger sensor than the D7100: APS-C (23.6 x 15.8 mm) versus APS-C (23.5 x 15.6 mm). It is very significant difference between these cameras because big sensor allows you to make pictures of the better quality. The D7100 offers a wider ISO range of ISO100–6400,Lo-1(ISO50),Hi-1(ISO12,800),Hi-2(ISO25,600) than 200-3200 ISO range of the Nikon D90. Such ISO numbers allow the camera owner to make good quality pictures in low light situations. The D7100 has more number of focus points than the Nikon D90: 51 vs 11. More focus points means less risk of losing focus lock while following a moving object.
The D7100 display is better as it has more number of screen dots 1,228,800 in compare to 920,000 dots of the Nikon D90 display. The higher dot count display is better for reviewing images on your camera. The Nikon D7100 provides better highest shutter speed - 1/8000 second.
The D90 which will help the camera owner to transfer pictures quick and easy. The D7100 is weather sealed which means that it will be safe even uncovered if you are out capturing photos in the rain or snow. The D7100 battery life is better than the Nikon D90 battery life. In accordance with CIPA standards you will be able to make 950 shots with the D7100 and only 850 with the D90. The D90 weighs 703g which is 62g less in comparison with the weight of the Nikon D7100.
Taking into account the above differences the D7100 will be the best choice. Check the list of the best offers on Amazon