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How to Clean the Viewfinder on Nikon D3300

How to Clean the Viewfinder on Nikon D3300

The Nikon D3300 is one of the most popular entry-level consumer DSLR cameras on the market. While it is a durable camera that can be used for a wide range of purposes, there may be some times when you notice some specks showing up when you try to focus on your image, an indication of a dirty viewfinder.

Although these specks will not affect the quality of your image or actually show up in the photograph, they can be very annoying and distract you from focusing on your shot correctly. Luckily, I have discovered a couple of simple steps for cleaning the viewfinder on the Nikon D3300 and other popular DSLR cameras.

Clean the Exterior of the Viewfinder

The first place to start is by cleaning the exterior of the viewfinder or the small box-like glass through which you look to focus on your shot.

While this may be an unlikely source of specks showing up in your photograph, if you are shooting in a dusty environment, or simply have not cleaned the exterior of your viewfinder in a long time, then it could be making your image appear a little grainy, especially as you zoom in.

There are several simple steps to cleaning the exterior of the viewfinder:

  1. Moisten a microfiber cloth or cotton swab with lens cleaner.
  2. Gently use a circular motion to clean the exterior portion of the viewfinder.
  3. Use a fresh microfiber cloth to wipe the viewfinder dry.

If you are the type of camera owner who likes to use all of the official accessories to service your device, a similar cleaning process can be used with the Nikon 7072 Lens Pen Cleaning System.

Blow Dust from the Camera Mirror

In an ideal scenario, simply polishing the exterior of the viewfinder will allow you to see crystal-clear images before you shoot. In reality, the specks you are seeing are likely the result of dust that has infiltrated the camera’s interior, requiring a bit more touch to clean properly.

Therefore, if you clean the exterior of the viewfinder and still see specks when focusing on a shot, then the next step is to blow away any dust that has accumulated on the mirror inside the viewfinder.

As mentioned, the mirror simply reflects the image being taken in by the lens, and any dust on the mirror will not show up in the final shot. However, dust on the mirror can definitely be distracting, so take the following steps to get it clean:

  1. Take the camera indoors to a clean, stable environment. As dust accumulation on the mirror is likely due to frequent outdoor shooting, attempts to clean the viewfinder outdoors can be counterproductive. Be sure that there are no open windows, doors, or blowing fans in the general vicinity when cleaning.
  2. Remove the camera lens and set it on a clean surface.
  3. With the camera facing down, use a ball blower to blow up into the mirror box, loosening any dust that has accumulated on the mirror surface. Although it is more comfortable to blow air into the camera with its face up, any loosened dust will settle back on the mirror, defeating the purpose. As a result, keep the camera facing down at all times when cleaning.
  4. Before reattaching the lens, use a flashlight and magnifying glass to see if any dust remains visible on the mirror.

One important note: it is never a good idea to try and use a blow dryer to loosen dust from the camera mirror, as too strong a stream can cause damage to the sensitive interior components of the camera.

Have the Prism Professionally Cleaned

After cleaning the exterior of the viewfinder and the mirror box, you still see specks visible when queuing an image, then a worst-case scenario has likely occurred, and you have gotten dust into the camera’s prism.

The prism is not visible when taking off the lens, and it is actually very difficult to get dust in the prism. The mirror reflects light taken in from the lens into the prism, so, in this respect, it actually serves as a dust barrier.

However, if shooting in extremely dusty, turbulent conditions, it may be possible that dust bypasses the mirror and gets up into the prism, creating a real cleaning challenge. The camera will need to be taken apart to gain access to the prism. Experienced photographers may feel comfortable performing this process, but it is best to take it to a camera repair shop to have dust removed from the prism.

As errors when cleaning the prism can actually introduce more dust to the viewfinder or cause damage to the camera’s interior components, and the cost to have the prism professionally cleaned can be high, it may be best to try and ignore the dust specks and shoot your best shots, as even a dirty prism will not negatively impact final image quality.


Having a dusty viewfinder in your Nikon D3300 can be quite annoying. Fortunately, the issue can usually be remedied by wiping down the exterior of the viewfinder or removing the lens and blowing dust free from the mirror. Even if you cannot get the viewfinder 100% free of all dust specks, take solace—a dusty viewfinder will not result in blurry photographs.