#12 Re: DUDA: Primeira Reflex!
Bueno, la Nikon D90 va más arriba de la XSi y más arriba aún que la T1i. Con respecto a la diferencia con la XSi, la XSi es de una gama mucho más baja, también es más antigua.
Te pongo los datos copiados de AMAZON y simplificados para que no ocupen mucho post:
Nikon D90 Product Features - 12.3-megapixel DX-format CMOS imaging sensor
- D-Movie Mode; Cinematic 24fps HD with sound
- 3-inch super-density 920,000-dot color LCD monitor
- Capture images to SD/SDHC memory cards (not included)
Technical Details - Color: Black
- Image sensor format: DX
- Image sensor type: CMOS
- Sensor size: 15.8 x 23.6mm
- Total pixels: 12.9 megapixels
- Effective pixels: 12.3 megapixels
- Top continuous shooting speed at full resolution: 4.5 frames per second
- LCD monitor size: 3 inches diagonal
- Monitor resolution: 920,000 pixels
- Angle of view: 170-degree wide viewing angle
- Slowest shutter speed: 30 seconds in steps of 1/3, 1/2, 1 EV
- Fastest shutter speed: 1/4000 second in steps of 1/3, 1/2, 1 EV
- Bulb shutter setting: Yes
- Lowest standard ISO sensitivity: 200 in steps of 1/3, 1/2, 1 EV
- Highest standard ISO sensitivity: 3200 in steps of 1/3, 1/2, 1 EV
- Lowest expanded ISO sensitivity: Lo-1 (ISO 100 equivalent)
- Highest expanded ISO sensitivity: Hi-1 (ISO 6400 equivalent)
- Storage media: SD, SDHC
- Storage system: JPEG: JPEG-baseline compliant, can be selected from size priority and optimal quality; AVI
- Exposure modes: Programmed auto (P) with flexible program, shutter priority auto (S), aperture priority auto (A), manual (M), auto
- Advanced scene modes: Portrait, landscape, close-up, sports, night portrait
- Exposure compensation: +/-5 EV in increments of 1/3, 1/2, 1
- Exposure lock: Yes
- Exposure bracketing: Yes, 2 or 3 frames in steps of 1/3, 1/2, 2/3, 1, or 2 EV
- Shutter release modes: Single frame (S), continuous low speed (CL) at 1 to 4 frames per second, Live View (LV), self-timer, continuous high speed (CH) at 4.5 frames per second
- Movie modes: HD 1280 x 720 at 24 fps, VGA 640 x 424 at 24 fps, QVGA 320 x 216 at 24 fps
- White balance: Sun, shade, fluorescent, incandescent, flash, preset, fine tune by Kelvin color temperature setting, auto, auto (TTL white balance with 420-pixel RGB sensor), 7 manual modes with fine tuning
- White balance bracketing: Yes, 2 or 3 exposures in increments of 1, 2, or 3
- Playback functions: Full frame, zoom, slideshow, pictmotion, histogram, shooting data, highlight point display, auto image rotation, sound playback, D-movie playback, thumbnail (4, 9, 72 segments), calendar
- Interface: High-speed USB, NTSC, HDMI
- Lens mount: Nikon F bayonet mount
- Compatible lenses: DX AF Nikkor, D-G-type AF Nikkor, AF Nikkor, AL-P Nikkor, non-CPU AI Nikkor (supported functions may vary)
- Picture angle: 1.5
- Viewfinder frame coverage: Approximately 96 percent
- Viewfinder magnification: Approximately 0.94x
- Depth-of-field control: Yes
- Focus modes: Single-servo AF (S), continuous-servo (C), manual (M) with electronic rangefinder, Live View autofocus (face priority, wide area, normal area)
- Focus lock: Yes
- Built-in flash: Yes
- External flash shoe: Yes
- Nikon Creative Lighting System compatibility: Yes
- Flash sync speed: Up to 1/200
- FP high-speed sync: Up to 1/4000
- Accessory shoe: Yes
- Battery life: 850 shots (CIPA)
- Item width: 5.2 inches
- Item height: 4.1 inches
- Item depth: 3.0 inches
- Item weight: 22 ounces
Canon XSI Product Features - 12.2-megapixel CMOS sensor captures enough detail for poster-size, photo-quality prints
- Large 3.0-inch LCD display; Enhanced Live View function
- DIGIC III image processor provides fast, accurate image processing; improved Autofocus and framing rate
- EOS Integrated Cleaning system, plus Dust Delete Data Detection in included software
- Stores images on SD/SDHC memory cards (not included)
Technical Details - Brand Name: Canon
- Model: XSI Body
- Optical Sensor Resolution: 12.2 MP
- Optical Sensor Technology: CMOS
- Optical zoom: 3
- Lens Type: interchangeable
- Optical Sensor Size: 22.2 x 14.8mm
- Included Flash Type: Pop-up flash
- Display Size: 3 inches
- Light Sensitivity: Auto (100 - 400), ISO 100, ISO 200, ISO 400, ISO 800, ISO 1600
- Shooting Modes: Close-up, Landscape, Sports mode, Portrait mode, Night portrait
- Exposure Control Type: Program, automatic, manual, aperture-priority, shutter-priority
- Viewfinder Type: Eye-level pentamirror
- Width: 5.1 inches
- Depth: 2.4 inches
- Height: 3.8 inches
- Weight: 16.8 Ounces
Canon T1i Product Features - New 15.1-megapixel CMOS sensor with DIGIC 4 Image Processor
- Body only; lenses sold separately
- Full HD video capture at 1920 x 1080 resolution; HDMI output
- 3.0-inch Clear View LCD; Live View Function for stills (Quick, Live and Face Detection AF modes) and video
- Capture images and video to SD/SDHC memory cards (not included)
Technical Details - HDMI output for HD viewing of stills and video.
- 3.0-inch Clear View LCD
- Auto Lighting Optimizer
- Wide range ISO setting 100-3200
- Compatible with over 60 Canon EF/EF-S lenses
- Recording Media: SD memory card, SDHC memory card
- Continuous Shooting Speed: Max. 3.4 shots/sec. (with One-Shot AF or AI Servo AF)
- ISO Speed (Recommended Exposure Index): ISO 100-3200 (in 1-stop increments), H1: 6400 H2: 12800; Basic Zone modes: ISO 100-3200 set automatically
- Dimensions (WxHxD): Approx. 5.1 x 3.8 x 2.4 in./128.8 x 97.5 x 61.9mm
- Weight: Approx. 16.9oz./480g (body only)
Tanto la Nikon D90 como la Canon T1i graban video en HD, la Canon en mayor resolución pero con mucho menos frames por segundo.
La Canon T1i tiene la ventaja/desventaja de tener más megapixels y mayor sensibilidad ISO máxima, el problema es que al tener más megapixel en un sensor APS-C (más pequeño que el DX de Nikon) los pixels tienen una ratio de compresión mayor, por lo tanto son pixels más pequeños muy amontonados, lo cual resulta en una mayor incidencia de ruido en las fotos tomadas con ISOs altos, no sirve de nada tener 64000 ISO si te va a salir una imagen que no te va a servir para nada serio y con detalles perdidos. Otra desventaja es que con lentes más estándar de Canon no vasa lograr una mejor resolución, si no más bien, se va a producir una especie de cuello de botella en cuanto a la resolución, lentes que te dan calidades magníficas en cámaras con menos Megapíxel, resultarían dando imágenes menos definidas debido a que ya no tienen la capacidad de enviar información detallada a pixels más pequeños y más comprimidos, por lo tanto, no quedaría otra que conseguir lentes de mayor resolución, en otras palabras, solo lentes pro sacarían el verdadero jugo al sensor. Esa es una realidad en cualquier cámara de alta cantidad de megapixels.
Lo que me gustó desde el principio en la D90 es su amplio rango dinámico -gracias al sensor que comparte junto a la D300- en comparación con las canon que ofrecen menos relación "Altas luces-sombras".