10 Reasons To Buy Raspberry Pi High Quality Camera From RenhotecIC


The Raspberry Pi Foundation has an amazing product: "Raspberry Pi High Quality Camera", a camera module that can be connected to an external lens. In addition to emphasizing that it can be connected to any C/CS mount lens, the official also launched two matching models The lenses are 6mm F1.4 for wide-angle and 16mm F1.4~16 for telephoto.

 

Raspberry camera comparison of past generations

 

Up to now, Raspberry camera has three specifications, which are Camera Module v1, v2 and the latest HQ camera. The comparison of specifications is shown in the table below

 

V2 is basically an upgraded version of V1, with higher resolution and wider lens. The only pity is that the CMOS size is slightly smaller after the photosensitive component is replaced from OmniVision to Sony. On the whole, V1 and V2 give users a stronger feeling of upgrading because of the increased resolution (5M x 8M) and wider viewing angle (53.5 x 62.2 degree). As for the HQ Camera, its photosensitive component CMOS is nearly twice as large as that of the V2, and the resolution exceeds the threshold of 10 million pixels. It has no built-in lens but provides an adapter function. It seems that it is a module designed for special purposes. The users are more professional, and only those who pursue shooting quality, photography enthusiasts, or experts in special fields such as optics and ecology may be interested in it.

 

How big is the sensor of RPi Camera HQ?

 

The biggest factor for the quality of direct photography is the size of the photosensitive element. The photosensitive element of this HQ Camera is said to be nearly twice as large as that of the V2, but how big is it? I arranged the commonly used camera CMOS sizes together and drew them into a chart for comparison, so as to better understand its size specifications.

 

The common cell phone CMOS size is 1/3", about 4.8mmx3.6mm, RPi Camera V1 and V2 are smaller than it, and HQ Camera is larger than the CMOS of cell phones, although it is still not as good as ordinary portable cameras 2/3" size, but the key point is that it can be connected with a variety of different photography lenses, and the quality of photography can be improved through good quality lenses. This has already made people eager to try. Perhaps, we should call it interchangeable lens photography. Modules might be more appropriate.

 

What lenses can RPi Camera HQ be adapted to?

 

RPi Camera HQ has a built-in C-CS (C-Mount to CS-Mount) adapter ring. Both C mount and CS mount are internationally recognized lens standards. The lens threads of the two are the same. The mount is 17.5mm, and the CS mount is 12.5mm. Since the distance of the CS mount is smaller than that of the C mount, the adapter for converting a C-mount lens to a CS mount is called a C-CS mount. This connector can be used for both C and CS mounts. There are two specifications of lenses, so the C/CS mount adapter ring used by RPi Camera HQ can be connected to C mount or CS mount lenses at the same time without colliding with the rear CMOS. (Conversely, a C-mount camera cannot be converted to a CS mount lens, because the C-mount requires a longer lens rear focal length)

 

What is the back focal length of the lens?

 

The back focal length of the lens is similar to but different from the flange distance (Flange focal distance). The back focal length of the lens refers to the distance between the last lens of the lens and the photosensitive component, and the flange distance refers to the metal ring of the lens interface. The distance from the sensor to the photosensitive component/film, for users who generally need an adapter lens, the flange distance is more meaningful, because it refers to the distance from the adapter ring to the photosensitive component, if this distance is too short, It will cause the rear lens to interfere with the CMOS and cause damage.

 

CMOS size and imaging size

 

Connect the same 50mm lens to full-frame, APSC, and PICamera HQ respectively, and you will find that there are very obvious size differences in the images taken:

 

The reason is that the size of the photosensitive component CMOS is different. It will be clearer to illustrate it with the picture below. The red frame is the imaging area (size) of the CMOS. It is assumed that the resolutions of the three are the same (for example, all are 1920×1080), and the same lens is used To shoot objects at the same angle, the fields of view of the photos taken are as follows, from left to right: 1. Full frame 2. APSC 3. PICam HQ

 

This is also the reason why a small DC or mobile phone can achieve a higher telephoto. Since its CMOS size is quite small, the imaging range is also quite narrow. If the CMOS can provide higher resolution (that is, each pixel is denser), Then because the imaging area becomes smaller and zoomed in to 100%, you will get a super high magnification telephoto effect. For example, the recent Huawei P30 pro and Samsung S20 ultra can achieve magnifications of 50 times and 100 times respectively. It is a gimmick to achieve ultra-high telephoto through small-sized photosensitive components and a resolution of more than 100 million pixels.

 

Therefore, 50mm is a standard field of view lens on a full-frame camera, a small telephoto lens on an APSC body, and becomes a telephoto lens on a PICamera HQ. The operation demonstration below shows that the advantage of the PICamera HQ external lens is that you can choose lenses with different focal lengths and larger photosensitive components, so that the Raspberry Pi can be used in different fields of photography. The video demonstrates three external lenses with different focal lengths: standard 50mm, fisheye 10-17mm, and telephoto 300mm. According to the CMOS magnification conversion (36mm/6.287mm=5.73), these three lenses will become the focal lengths of 287mm, 51-97mm, and 1719mm. Therefore, 1719mm has reached the super telephoto range.

 

Using the Raspberry Pi with the external lens of PICamera HQ, we can replace lenses with different focal lengths/apertures for different needs and scenes, and obtain the benefits of telephoto and large aperture that were lacking in the past PICamera or USB Camera. If you consider adding AI Auxiliary, it can detect animals and birds at a long distance in the wild for automatic shooting, without the need for human patience.