I bought D40 on May 1 day, and the day before yesterday, I found a stain on the same position in the photo.

1.There may be dust inside the CCD or lens. Customer service will handle it during the warranty period.

2.CCD is behind the reflector, so it can't be seen at ordinary times and can't blow off the dust inside the lens. For photographic equipment, needle-tip dust may leave a stain on the photo, which is normal for you not to see.

Take your warranty card and purchase invoice and go directly to the local after-sales center, and they will handle it for you.

4. General camera cleaners include: forced blowing (or canned compressed air), lens brush (also called lens pen) and non-woven mirror cleaning cloth.

It should be pointed out that:

1. Don't blow with your mouth, because saliva may splash on the lens or CCD to form stains.

2. Don't wipe the lens with chamois or paper towels, which is likely to wear the lens coating.

3. Don't wipe the reflector. The coating on the reflector is very fragile and almost all of it has been wiped off. Dirty reflector will only affect the brightness in the viewfinder, but will not affect the imaging. Just blow it clean, so as not to scratch it and you will not be able to view it. Similarly, don't wipe the focus screen.

4. If there are grease, saliva and other stains on the lens, do not use any organic solvent such as lens water to clean it, which is likely to damage the lens coating and then scrap the lens. For stains that are difficult to erase, you can dip a small amount of distilled water or deionized water into a clean non-woven mirror cleaning cloth to soak the stains, and then gently wipe them with a dry non-woven mirror cleaning cloth.

5. When wiping the lens, you should start from the center and wipe it spirally in one direction.

In addition, I suggest you buy some color-changing silica gel (desiccant) and put it in a gauze bag with the equipment to prevent the equipment from getting wet. The color-changing silica gel will change from blue to pink after absorbing water, so that the use of desiccant can be seen intuitively. After the silica gel turns red, you can dry it again with a hair dryer, but be careful that the temperature is not too high, otherwise the silica gel will break.