Seems that you're minimizing parallax issues as discussed in the zerene systems link Bill produced earlier for certain subjects and use cases are much more variable than this. This is a huge feature and the fact that Thom didn’t offer guidance to your satisfaction is disappointing indeed! Don’t let DOF strawmen change your perspective. This is a good topic for discussion on the forum.īill, you were rightly justified to criticize. Lloyd Chambers (Diglloyd) states that this is a major advance and gives some pointers on his experience with on his pay site.
The "Focus Shift" capability is an important feature of the D850 and we need to know how to use it. I was disappointed that Thom gave little advice on what step size to use and how many shots to take, but as you point out this is no simple matter. We had a meaningful discussion and I must confess my initial post was a bit too harsh. I did report the error to Thom as well as my concerns about how little information he gives on how to use what Nikon inappropriately calls Focus Shift (causes confusion with optical focus shift when stopping down with fast lenses). In regards to the errors you pointed out, he does list a contact and wishes to hear feedback on errors. Now add to that focal lengths extending from 14-800mm, distances extending from cm to km, apertures ranging from f/1.4 to f/22 and now try to suggest some appropriate settings to fit concisely in a book you are already deeming too long and complex. On a FF sensor at 300mm the DOF at those settings is about 4cm, whereas the DOF on the 14mm example extends from less than a meter to infinity. Pick a few examples how about 300mm at 5 meters and f/2.8 vs 14mm at 50 meters at f/8. Just looking at DOF tables one sees too many variables based on focal length, subject distance, sensor size, and aperture to arrive at a quick formula.
Nasim Mansurov does better in his free review. Too many variables he said, but that is a cop out. I was looking for guidance on the focus shift facility for image stacking, but he was too lazy to give any recommendations on what settings to use.
Then you leave the perspective intact and only slightly change the size of the projection between images, which as you said can be adjusted by the stacking program. The best way to do focus stacking is to use a rail with a bellows and move the camera to focus between shots. If you leave the lens untouched but move only the sensor to focus you do not change the perspective but only the focus and (slightly) the magnification. If you use a rail to move the lens (or focus the lens with the focus ring) you change the perspective. I don't know what you mean by focus group and "move the sensor cq camera". The stacking application can easily deal with changes in magnification, but changes in perspective caused by moving the camera (e.g. Then you have the problem that the image projection size on the sensor differs between shots if you fix the camera and refocus by moving the focus group in the lens (you should fix the focus group and move the sensor cq camera).
I use qDSLRdashboard on an Android phone at the moment using WiFi. It can be used with electronic shutter, eliminating wear on the mechanical shutter and vibrations from the mirror and shutter. Who wants to deal with tethering via USB in the field? It's a big PITA! IMHO, the focus shift feature is a big deal. It's not a ' huge feature' at all, external programs offer this feature for ages when tethered to a phone or a laptop.