# What aperture to use to get the same DOF as in a panoramic image

When I take a panorama with a 80mm lens at F/2.0 on a fullframe body such that the resulting image has a equivalent field of view of a 50mm lens on the same body, what would then be the equivalent aperture I would need to use on the 50mm lens to get the same DOF as in my panorama?

Im guessing F/1.25. There I calculated the factor 1.6 = 80mm/50mm and divided 2.0 by it. If this is the right way to calculate the equivalent aperture, what is the physical reason behind that?

• "When I take a panorama with a 80mm lens at F/2.0 on a fullframe body such that the resulting image has a equivalent field of view of a 50mm lens on the same body," This does not make sense to me, an 80mm lens does not have an "equivalent field of view" on a full size sensor camera, it has a field of view of 80mm. Perhaps you have stated it backwards. Also a 80mm would not give a panoramic view. Clarification is needed. F2.0 with a 80mm lens is going to give you a shallow depth of field, is that your goal ?? Commented May 12, 2020 at 17:09
• @AlaskaMan just a gues, but I think he means that he wants to take two or more photos whith an 80mm lens and stirch them toghether to get a FOV equel to 50mm Commented May 12, 2020 at 17:24
• @Jonas thats true. That is what I mean.
– Arji
Commented May 12, 2020 at 19:38
• @Arjihad Your question is based on a bit of a misconception regarding what Depth of Field (DoF) is and what it is not. There's no real thing as "the" depth of field of any image until the display size and viewing distance is factored into the equation. For more, please see Is camera lens focus an exact point or a range? Commented May 16, 2020 at 5:33