I was shooting some of my sons Thomas Trains close up yesterday using my 35mm f/1.8. I was changing the f stop and looking at the changes in DOF and comparing it to what i see my DOF calculator. This is something I had played with while shooting random pictures but just taking the exact same shot(fixed object - shooting from a tripod) at increasing (or decreasing) f stops is a good begineer exercise.
I was wondering how the DOF would changed if I switched lenses to my 24-100mm and zoomed to 100mm, stepping back to frame the picture in exactly the same manor(Thomas the train taking up about 3/4 of the image). From what I read - if I increase my distance to counter-act the increase in zoom I am making two inverse changes and should have basically the same relative depth of field as i had on the 35mm.
That being said - when shooting close ups (in my son's toys and action figures) is there some reason to step back and zoom in with 100mm rather then get closer and use my 35mm? My 35mm goes to f/1.8 while my 24-120mm is in the f/5.6 range depending on zoom.
I was wondering how the DOF would changed if I switched lenses to my 24-100mm and zoomed to 100mm, stepping back to frame the picture in exactly the same manor(Thomas the train taking up about 3/4 of the image). From what I read - if I increase my distance to counter-act the increase in zoom I am making two inverse changes and should have basically the same relative depth of field as i had on the 35mm.
That being said - when shooting close ups (in my son's toys and action figures) is there some reason to step back and zoom in with 100mm rather then get closer and use my 35mm? My 35mm goes to f/1.8 while my 24-120mm is in the f/5.6 range depending on zoom.