The Nikon P900 sports a zoom lens 4.3mm thru 355mm. Nikon advertising claims this lens yields the equivalent of 24mm thru 2000mm. When taking equivalent, they are making a comparison using the venerable 35mm film camera as “standard”. They do this because the 35mm film camera has been with us for nearly 100 years and most of us “gray hairs” know how a 35mm film camera preforms.

When making this comparison we calculate a magnification factor, most often called a crop factor. Nikon has already published that when this camera is set to 4.3mm (its minimum zoom), it functions the same as a 35mm film camera with a 24mm lens mounted. Thus the magnification factor is 24 ÷ 4.3 = 5.58. Working this problem using the 2000mm equivalent --- 2000 ÷ 355 = 5.63. Seems we get two different answers however they are close so let’s average and deciare 5.6 as the real magnification factor.

So you want to know when you zoom and achieve the equivalent of a 300mm lens? We divide 300 by 5.6 = 53.6. That’s the answer, when your metadata reveals the actual focal length was about 50mm or perhaps a little more (53.6mm) then the angle of view delivered will be the equal of a 300mm lens mounted on a 35mm film camera.

Hope this helps.

P.S. The P900 sports a 1/2.3 image sensor. This data is cryptic – the dimensions are in inches and describe the diameter of the silicon chip that was used when making the imaging chip. This data dates back to the diameter of early image tubes used in TV cameras of a bygone era. In other words the data is not current. The P900 image chip yields an image size 4.55mm height by 6.17mm length. To work the magnification factor we find the diagonal (corner to corner measure) = 7.66mm. Now we find the diagonal measure of the 35mm film camera image which measures 24mm height by 36mm length. The diagonal measure = 43.2mm. Now we divide 43.2 ÷ 7.66 = 5.6 the magnification factor.