1. Canon Canon is the best marketing among all SLR brands ... followed by the most powerful function of the fuselage ... mainly reflected in the powerful noise reduction and focusing speed of the fuselage ... Although some people say that Canon has improved the focusing speed at the expense of intensive reading ... Canon uses CMOS as a photosensitive element, and the noise is relatively small. This is a huge advantage ... EF bayonet has many adapter rings ... such as M42, R, MD, CY ports ... It is convenient to use classic manual lenses, but some lenses will be large because of the reflector (that is, they will touch the lens when lifting the reflector ...), and Canon's own lenses basically have mirror motors, so don't worry that the low-end machine can't focus the lens automatically ... And the lenses in the sub-factory are all from Canon's ports first. Some people say that it is a focus design problem, but the probability that the original lens is out of focus is not great ... Canon's own low-end lenses are also very rich ... Canon's dominant lenses are 200mm/ 1.8L, 85mm/ 1.2L, a bunch of white guns, 17ml shifting axis, 50mm/65438+. 24 mm/1.4 liter ... but ... the zoom lens is a weakness ... many zoom L have not been updated for more than ten years. The resolution on the semi-SLR is a bit insufficient ... The 27MM model is soft (to put it mildly) ... The conversion index of the semi-SLR is 1.6 ... That is to say, the lens mounted on the semi-SLR is multiplied by 1.6 ... Except for Olympus, everything is 1.5 ... That is to say, the wide angle is 60. Canon's machine is 28.8MM ... The wide-angle disadvantage is obvious ... Let's talk about the lens first ... Although Xiaobai is very famous ... In this focal length, even the lens of the deputy factory despises the imaging quality of Xiaobai from time to time ... So Xiaobai and Nikon's small bamboo cannons have been updated (changed) ... There is another weakness like Nikon's ... It costs a lot of money to have one more anti-shake ... But on the telephoto lens, Mirror image stabilization is better than fuselage image stabilization ... because the image seen by mirror image stabilization is easier to compose without shaking, and if the fuselage image stabilization ... composition is more difficult ... There is another problem that Canon's low-end machine personally feels that the shape is not so good ... Everything under 50D is plastic, and the plastic feeling is very heavy. And the shape is not tough ... 2. Nikon Nikon has many advantages ... First of all, the style problem ... Nikon's film will be developed in this machine ... to produce bright and vivid colors ... very pleasant ... At the same time, Nikon's mouth is also very convenient, and most other Japanese manufacturers have changed the bayonet. But Nikon didn't change it ... all kinds of old lenses, old deputy factory lenses can be used ... but you can only measure A file if you buy a car body above D90 ... At the same time, Nikon's D lens is cheap. It's very affordable ... but the fuselage needs more than D5000 to focus automatically-Nikon's CMOS machine is also very strong in noise reduction ... The software (NX) for processing RAW pictures is also very powerful ... Nikon's dominant lens: 14-24/2.8 (golden wide angle), various VR anti-shake black guns, 58 mm/65438. 28 mm/1.4 ... The disadvantages are obvious ... First of all, the films are all machined, which leads to the dry hair being bright and sharp, but it sacrifices the level to some extent ... If you want to have your own style completely, you can only turn on RAW (Nikon's corresponding format is NEF) ... At the same time, Nikon's photosensitive elements are unified by Sony ... The difference with Sony is the main control. In addition, Nikon's development of lenses with mirror motors is very slow. Moreover, Nikon's bayonet is too small ... which leads to the limited choice of low-end eunuch lens and the difficulty in producing high-end large aperture lens ... So if you buy a low-end Nikon machine, you have to match the lens of the deputy factory ... And Nikon's characteristics: the cow's head is not cow, the dog's head is not dog ... The effect of the cow's head is really not as good as expected, which is reflected in the price ... 3. Sony's advantage lies in the lens ... The old lens left by Minolta and the new Zeiss and G head. Other Zeiss heads are NB ... and Minolta has left many classic heads ... Because of the popularity of Zeiss heads, many of Minolta's top heads have flowed into the second-hand market ... You can buy exaggerated lenses at a price that is not very exaggerated ... such as 17-35/3.5g, 28-70/2.8g, 80-200/. 85/ 1.4GD ... This kind of camera is only 6000-8000 ... and the brand-new Zeiss head and Sony G head are thousands of pieces higher (shame) ... At the same time, Sony, Pentax and Olympus all have anti-shake cameras, so all lenses have anti-shake cameras ... It is also very convenient for Sony to switch to M42 port, mainly with cameras for anti-shake. Increased the practicality of the old lens ... Sony's advanced lenses: 135/ 1.8za, 70-200mm/2.8g, 300mm/2.8g, 24-70mm/2.8za ... Sony's shortcomings are very obvious ... Although second-hand can make up for ... the poor performance of the fuselage ... the noise is worse than any other one (slightly improved now) ... and the price of advanced lenses (Zeiss and G-head) is exaggerated (but it has been reduced to the price similar to that of NC) ... And there are Sony's characteristics: the dog's head is very dog and the cow's head is very cow ... The low-end can only be made up by Minolta's head, and when Minolta's lens is installed on Sony A900, In fact, CN also has this problem, but there is only one D3X that is rarely used in N families, which will reflect this problem ... MD bayonet is Minolta, but it can only be used on Sony machines with adapter rings, and there are corrective lenses, which will seriously affect imaging ... 4. The imaging color of adhesive is very beautiful ... The lenses are also very good ... The low-end cameras are the cheapest in all families. In addition, they all have body motors, which can measure the light of old lenses ... There are many lenses in Pentax that are 2000 yuan, such as 16-45mm/4 ... and Yincui gorge can go on ... Pentax lenses are strong, but not outstanding =. = |||| It is more suitable for tossing ... and three manual bayonets (M42, MD, PK) can be directly installed on Binder's machine ... cheap ... and other adapters can be easily used ... Advantages: Yincui gorge, 200mm/4 macro (if you can afford it = |||) Disadvantages ... Disadvantages are very bad ... Pentax's marketing is the worst among all Japanese brands ... It's very troublesome to buy in Chinese mainland ... It's even more troublesome if it's broken ... The focal length of Pentax lens is weird, and there is a magical cycle: the new lens is not as good as the old one .. and there is no new Pentax lens. There is no whole body ... only Xiaojin (80-200mm/2.8) is similar to Xiaobai ... you can't buy it under normal circumstances. A few days ago, I saw a second-hand sale of 13000 ... Nikon's confocal parts cost less than 7,000 pounds ... Pentax's photosensitive components are produced by Samsung (the early Kodak) ... Pentax is expected to be acquired by Samsung ... At that time, if Pentax is properly marketed and published in full, it may make a comeback .. 5. Olympus is a very individual manufacturer. And there are quite a few optional settings ... but at the same time, it is relatively small ... Olympus's machine is smaller, but the powerful lens is very huge ... The aperture of Olympus zoom lens may be the most exaggerated in all families ... Because the conversion coefficient is 2, it is easy to expand the aperture ... At the same time, Olympus's fuselage anti-shake is also the most powerful of all fuselage anti-shake ... Because of the distance between the bayonet and the flange, It is very easy to switch to the old lens ... and many machines are more suitable for female users ... Advantages: 7- 14-24mm/4 (equivalent to 14-24mm/4), 14-35mm/2 (equivalent to 28-70mm/2). Olympus can't produce Quan Huafu digital SLR ... and at present, Olympus mainly uses M4/3 system, which is a big market for these things ... Canon 5D mark II and Sony A900, which I'm not familiar with. I like Canon 5DM Mark I. Generally speaking, I only consider Canon Nikon Pentax. Even if Sony's advertisement is good, I still don't think much of him. Although Nikon uses cmos made by Sony, the image is not just cmos. There is also the reason for its own image processor, and you said that Canon 450D has no video function, because I will not rashly use the video function on my machine, because it hurts cmos Olympus, so it is not recommended to get to the point. 500D 550D can be considered, but the lens is best not to 18-200. Although this is convenient, it has changed from wide angle to medium telephoto, and the image quality must be discounted. Some people say that poor hand feeling is not a problem, so am I. I think I will mind a little, because maybe I am used to using metal machines, which are as hard as toys, but it does not prevent them from being good machines. Relatively speaking, the D90 is slightly better. After all, if the best seller is not the Pentax Blower, some people say that it does have a small lens group, but what about those old people? For example, the Phoenix Head in China is handmade, but the quality is good and it is very cheap.