How to choose a SLR camera so as not to be cheated by those profiteers?

The ultimate entry for beginners to buy SLR

Friends who buy SLR cameras for the first time often feel troubled or confused about how to inspect the machines on the spot before selling them. There are also many articles on the Internet that introduce the experience or precautions in aircraft inspection, but they are often not comprehensive and clear enough.

Here, I want to write something based on my on-site experience of buying SLR cameras many times. For those who have no experience in on-site purchase.

In addition, friendship emphasizes

■ SLR cameras are, after all, the product of a high combination of electronic technology and precision optical technology. Be sure to check it carefully when you buy it. There are definitely advantages and disadvantages. Remember-you can't be too careful.

■ In view of the fact that both SLR cameras and lenses are expensive optical equipment, the inspection process is complicated. Unless absolutely necessary, it is strongly not recommended to buy SLR products and their lenses online.

Here are the whole steps:

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■ Items to be carried before departure:

1, notebook. There must be four softwares installed in it: Exiftool GUI (used to check the shutter number of the new machine), bad point test (used to detect the bad point of CCD or COMS), ACDSee 10 (browse RAW) and Photoshop.

2. If you don't have a notebook, bring a USB flash drive and the installation procedures of the above four softwares, and then you can use the JS computer.

3, a friend (it doesn't matter whether you know the camera or not, your eloquence is better)

4. RMB

5, white gloves (it is best to wear when checking the machine. In case JS gets into unnecessary trouble)

■ Tell JS the truth before testing the machine (the following is my general practice, for reference only):

1, if there is anything wrong with the CCD, don't.

2. If there are more than three bright spots (including three) on the LCD screen, please don't.

3. If there are obvious dust, fingerprints or even other marks on the lens, don't.

4. If there are obvious handprints on the LCD screen of the fuselage, don't.

5. If the battery contacts are obviously bright, the battery should not be used.

6. If there are fingerprints or obviously strange marks on the fuselage reflector, don't.

7. If the shutter number exceeds 300, don't use it (this article is only valid for Pentax machines).

8. If I can provide obvious evidence to prove that this machine is a parallel product (for example, the warranty card number in the box doesn't match the body number), I don't want it.

9. Other major defects (can be agreed with JS)

■ Inspection process:

1, bring me the box, and simply check the packaging of the box, mainly to see if there are any signs of unpacking.

2, don't let JS open it, let JS stand far away and unpack it himself.

3. Open the box and check the documents, warranty cards and accessories one by one. . . Wait, a lot of things. Don't touch the fuselage and lens for the time being.

4. Put on gloves and check the fuselage. Mainly depends on whether there are fingerprints on the LCD screen, and whether there is obvious dust in the viewfinder, battery compartment and card compartment.

5, open the fuselage cover, quickly check the reflector and lens bayonet, make sure there is no problem, cover the fuselage cover as soon as possible (pay attention to this action, because the reflector is exposed for a long time, it is easy to get dust on the fuselage, JS will not do it. In addition, don't dig the reflector with your hands or anything else. It is estimated that JS will not do it either)

6. Unpack the lens and check the lens. Mainly check whether there are obvious traces on the mirror surface and lens barrel (the mirror surface of a brand-new lens is quite clean), aim the lens at the light source, and check whether there are obvious foreign objects inside. Shake the lens gently twice to see if there is any obvious loosening sound. Check the lens bayonet to see if there are obvious traces of bayonet contacts.

7. Check the battery, mainly to see if there are obvious bright spots on the contacts. If there are obvious bright spots, it can be suspected that it is not a brand-new battery.

■ Start installing the battery, turn it on, and check the bright spot of CCD.

1, turn it on, take a few photos casually, and let the machine warm up for 2-3 minutes.

2. Cover the lens cover and set it to full manual mode.

3. The machine is set to the maximum aperture, the shutter number is 2 seconds, the noise reduction in the machine is turned off, and the anti-shake is turned off.

4. Take a picture of each ISO value from ISO800 to the highest ISO (generally to ISO 1600). Save in RAW maximum format.

5. Import the black image into the computer, convert it into JPG format, and measure each photo with the bad point test software.

6, if the test results have bad points (note that it is not noise. Noise doesn't matter), write down the coordinates of each bad point. See if the bad points in each picture show coordinates.

7. Adjust the "bad point limit value" in the bad point test to 200 and 150 respectively, and then repeat the process of 5 and 6.

8. In a well-lit environment, face a blank sheet of paper, make exposure compensation of+1, and then repeat steps 3 and 4.

9. Import all-white pictures into the computer, and in Photoshop, display these 100 pictures in reverse color as black pictures and save them. Repeat the process of 5, 6 and 7.

■ Use Exiftool GUI to check the shutter number of the camera.

How to use the Exiftool GUI software and how to check the shutter can be searched online by yourself. There are many related contents and they are very simple. Let's not talk nonsense here.

■ Let's check the LCD highlights (this is relatively simple).

1, cover the lens and shoot all black.

2. Zoom in and browse on the LCD, and observe with the naked eye whether there are bright spots.

■ If all the above processes are normal:

1, take more pictures.

2. First put everything (note, everything) in the box and seal it, and then pay the money (avoid changing bags and accessories when JS pays the money).

Step 3 pay for it

4. Invoice

5. Ask for the business card of the store.

Step 6 leave

Finally, add one point:

Many netizens said that if it is a new machine, after plugging in the battery, the first screen displayed should be "language selection" and "date and time setting". Otherwise, you can suspect that it is a second-hand machine.

Now it seems that this statement is not completely correct. I bought the machine with my friends several times, plugged it in and turned it on. The pictures of "language selection" and "date and time setting" are correct, but merchants often ask you to skip these two pictures instead of setting the language and date. The reason is: the merchant is worried that this machine will not sell well after you set it up.

Therefore, after booting, above the fold is "language selection" and "date and time setting", or it may be a second-hand machine or even a prototype.

Be sure not to be careless.