HD ready, Full HD, Ultra HD. which definition to choose?
The resolution of a projector is one of the main features (along with brightness ). The higher, will better the image sharpness.
HD and 4K
The resolution of a projector is the number of pixels that it can display. It is expressed in [width] x [height]. We speak of native resolution to express the “real” resolution of the projector.
There are several resolution “standards,” of which the most common is the HD format (High Definition 1920 x 1080 pixels). Below is the list of the top video and computer resolutions.
Video Resolutions and Formats
These are the standard resolutions for television, movies, and video games. Since the switch to high definition, the default format is 16: 9.
The main current resolutions
- SD (standard definition) : 720 x 576 px
- This format was the standard before the advent of HD; it is on the way out.
- 720p (HD ready) : 1280 x 720 px
- HD compatible It’s “small” HD, aimed at small budgets and small to medium-sized screens.
- Full HD (HD 1080) : 1920 x 1080 px
- The standard (TV, video games, VOD, Blu-Ray, etc.), especially since the switch from TNT to High Definition. The format of the vast majority of home theater projectors is the recommended one, if possible. You will often find the term 1080p to refer to this resolution.
- Ultra HD (UHD) : 3840 × 2160 px
- The resolution is four times that of full HD. It’s the high definition of tomorrow, but most models are costly, and there is still too little content available.
- Ultra High Definition is often also called 4K by abuse of language (These are two very similar formats, but 4K is a cinema format, with a resolution of 4096 x 2160 px).
- More information on 4K / UHD
Which resolution to choose?
For home cinema or TV use, the full HD 1920×1080 resolution is strongly recommended. However, you will obtain a decent result with a resolution of 720p (1280 x 720).
As for 4K, if it is undoubtedly a future standard, it is still a relatively rare format (few models and high cost). The offer in terms of content (movies, 4K video games, etc.) is multiplying, and it is only a matter of time before UHD on par with it becomes a common alternative to HD.
Difference between 1080i and 1080p
Both terms refer to the frame rate for a 1920 x 1080 HD resolution. To be precise, we would write 1080 / 50i or 1080 / 50p. The second number (50) corresponds to the frame rate and the letter (i or p) to the scan type.
- “i” / interlaced: These are half-images. The 50i can thus display 50 half-images per second or 25 images / s.
- “p” / progressive: These are complete images. So 50p corresponds to 50 full frames per second and gives a much smoother rendering.
A high frame rate (50p or more) gives a strong impression of reality but a less “cinema” feeling. Indeed, the films are shot at 24p, i.e., 24 images per second, and the eye associates this frequency with the “film” rendering.
Computer Resolutions / Formates
Office projectors often have “computer” resolutions, similar to those of computer screens.
- SVGA: 800 × 600 (4: 3)
- XGA: 1024 × 768 (4: 3)
- WXGA: 1280 × 800 (16:10)
- WUXGA: 1920 × 1200 (16:10)
SVGA resolution will be sufficient to display text, but photos will appear pixelated. The choice will depend on your needs and your budget.
Note that it is quite possible to project a 1920 x 1080 HD film or program with a different resolution or format device.
4: 3 or 16: 9 aspect ratio?
Format refers to the aspect ratio of the projected image. There are three main ones: 4: 3, 16:10, and 16: 9.
For today’s cinema, HD TV, and video games, the king size is 16: 9. Except in exceptional cases, it is advisable to invest in a video projector of this format (on which it will also be quite possible to project a 4/3 image if necessary).
For business use (PowerPoint presentation, etc.), 4: 3 has long been the norm, but 16:10 and 16: 9 formats also tend to dominate in this area (for example, the default format PowerPoint presentation in Office 2013 is now 16: 9).
HD content: TNT, Blu-Ray, VOD,
To fully enjoy your projector, you should ideally have HD content. The sources are numerous:
- TNT television, satellite, or Internet via your box
- Movies on VOD, on Netflix, Canalplay, Orange VOD, etc.
- Blu-ray discs, the successor to DVDs
- HD video games, on PS4, Xbox, etc.
You may forget your DVD collection, the quality of which is no longer sufficient (especially if your projector has a full HD resolution and you have a large screen).
Difference between Blu-Ray and DVD
Blu-Ray is the successor to DVD. The main difference is the picture resolution: DVD movies are in standard resolution (SD) while Blu-Ray films are highly defined.
DVDs can be viewed through your projector even if it is full HD. However, the image will appear much less clear than with a Blu-Ray.
NB: The larger the screen, the more the difference in quality will be visible. A DVD will give a decent picture on television but a poor image with a projector.
Moreover, if almost all programs are now available in full HD, this is far from the case for UHD. If you have a “4K” projector, there are, unfortunately, still relatively few Ultra HD programs available (although the offer is growing day by day).