Auto fine tune focus on Nikon D850

Yesterday I did Auto AF fine tune for the two main lenses .. 24-70mm and 70-200 +/- TC 14E III on Nikon D850.

 It took me a good 2 hours

I had to buy a collar for the 70-200 f4 to put on tripod safely ..

I did each lens, at each focal end, 10 times. I then averaged the value for the lens .. while keeping the values for each end saved on my mobile, in case I want to use at one end or the other exclusively in a critical shoot ..  I had to do the 70-200 with and without the extender ..

 The reason for doing 10 times each one is that the process is so critical .. even pressing the button on the camera makes a very fine vibration, that affects the value significantly .. I think Nikon have to change the process, so it is hands free, using a shutter release cable or timer instead.

 At the end of the day .. the 24-70mm was spot on .. calibration value is zero .. i.e. doesn’t need any

 The 70-200mm value is +5 without and +7 with Teleconverter

 Wow .. that was a whole evening ..

 It is easier than AF fine tune manually .. because I am depending on the camera to give a value, rather than trying to decide myself, based on a chart photo, which value to go for .. It is not as easy as they meant it to appear. There is some software out there that can do that, but still requires a lot of trials. I used a Datacolor Spyder LensCal as my target, only because I owned it already.

 Averaging across focal end lengths and doing it at certain distances, showed the value different for different focal lengths and distances .. I therefore did it for longest Focal Length first, wide open and nearest subject first .. because that’s the shallowest DOF, as my main value, then for the shorter focal length .. Anything placed further or using the wider focal length, and the DOF would give enough tolerance for good focus, without the need of fine adjustments, as long as the lens is not an outlier of course. I averaged the values, with more weight towards the longest focal length value.

It is easier to do on prime lenses.

 

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Philosophy of Lenses for Amateurs

Amateurs get a raw deal when it comes to lenses .. There are the professional built-like-a-tank big, heavy and terribly expensive lenses .. and there are the cheap consumer lenses .. In-between, most lens manufacturers make some amateur lenses .. So amateur lenses are probably double the price of consumer ones, and are better built in that they are weather sealed, have full-time manual focusing, silent ultrasonic wave motors and metal mounts.

Beyond that .. Amateurs have to think of the range .. a wide angle, a standard zoom and a tele-zoom, plus a macro lens.

In full-frame an example would be the Canon 17-40 f/4 L, 24-105 f/4 IS L and 70-200 f/4 IS L. In Nikon the equivalents would be the AF-S 16-35 f/4 VR, 24-120 f/4 VR and 70-200 f/4 VR or 80-200mm ED. I would also add a 50mm f1.8 of sorts and a 100mm f2.8 macro ..

To me the main and most important lens is the walk-about 24-105/120 lens, which I use 80% of the time .. I do cityscapes, landscapes, still life and portraits.

Those who do sports, racing, or wild-life may find this setup very short or slow for them .. I envy those photographers who do only one type of photography .. like a macro hobbyist only needs a 100mm f2.8 macro .. !!

Amateur Photographers

The idea that amateurs do not need or deserve good cameras and lenses is not true.. The only difference between amateurs and pros is that the latter make a living out of photography, while the former produce artistic work without depending on photography to make a living. So amateurs are free to photograph what they like when they like and how they like .. As they do not do that 24/7, the lenses and bodies do not need to be built like tanks to take a beating .. but they still need decent quality to make good photos

“We are all apprentices in a craft where no one ever becomes a master.” Ernest Hemingway