First, it as a very useful
feature, not only for macro work.
But it only works with
AF-s lenses. Which means no old AF lenses like the Micro Nikkor 200
mm f4 AF or third party lenses like the Tokina 100 mm f2,8 Makro will
work with this feature (it is greyed out in the menu). That is sad as
both are optical very fine lenses on the D850.
Nikon claims that the old
AF system is not accurate enough, but with the qdslrdashboard app or
helicon remote you could use these old lenses and achieve good
results. For practical reasons these apps are used best with Wifi.
As others have already
stated the menu of focus shift shooting is not very user friendly.
But with a few tips it is quite easy to setup.
First thing is you set the
lens to the nearest point you want to be sharp. Then you go to the
camera menu scroll to the end of the list to “focus shift
shooting”. There you have six submenus:
No. of shots:
You can set a high number
like 50 or even 100, because the camera will stop automatically at
the end of the lens range. So some stacks will only produce five
shots, macro shots can consist of 50 shots or more though. With
modern AF-s lenses the end of the lens range is beyond
infinity. Mathematicians and Astronomers will get some hiccups with
the concept “beyond infinity” but lenses need to have some
tolerance at this point to focus properly at different climates and
on different camera bodies. This means you will get some unsharp
shots at the end of the stack, especially at landscape shots.
Focus step width:
1 means very fine
increments, but 5 is normally a good compromise working for most
situations.
Interval till next
shot:
0 sec, I do not see any
reason for any delay here, shutter shock is no issue because of
silent shooting.
Exposure smoothing:
I work in manual mode and
Auto Iso is off, then exposure smoothing is not necessary, therefore
set to “off”.
Silent photography:
On, very useful, because
no shutter shock and as the name suggests really silent.
Starting storage
folder:
You can have for every new
stack a new folder, but there is one bug which I find not so good.
After the last stack the normal pictures are written in the folder of
the last stack. So I use just one folder for all of my Raw files,
download them to the computer via Lightroom and separate them
afterwards with the command “Stack”.
As mentioned before I am
not so happy that my two AF macro lenses do not work with this
feature, and as my 45 mm and 85 mm Shift-Tilt lenses are manual focus
there is no use for them either.
But depending on your
subject there might be simple solutions working very well. I used my
simple 50 mm Af-s f1,8 lens with extension tubes (you need a version
with electric contacts, not the cheap manual ones) and I got great
results with stacked flower shots. Certainly the nearer you go to 1:1
or beyond that a good macro lens might get you sharper results. I
used also a Marumi diopter lens on my Nikon 85 mm AF-s f1,8 with
similar very good results. There is one difference that might be
important. While a macro lens can focus from 1:1 to infinity, a lens
paired with extension tubes can not do this. So depending on the
range of sharpness you want to achieve, the cheap solution might work
or not. But extension tubes are very lightweight, so from now on I
carry them with me again.
 |
| 50 mm AF-s f1,8 and 12mm extension tube, f8, tripod, Led and natural light, stack of 24 shots rendered with Helicon focus method "C" |
Software:
Photoshop has a stacking
feature I have used a few times. But as you cannot control the
parameters, the output is from excellent to almost useless. And it is
slow. I tried Zerene Stacker but I did not like the interface so much
(personal thing). I now use Helicon Focus. There are three methods to
stack your files (A, B, and Pyramid) and you have to play around to
see what method is best for the different stacks (landscape,
macro,...). I found the help menu quite useful for getting a starting
point. The software got recently an update and is also available in
different languages. End 2017 there is a discount available directly
on the Helicon focus website. I choose the unlimited lite license. This was a mistake, as the very good retouch function is not included in the lite version (you should always read the small print). The other pro features, like
Helicon Remote or 3D output are not so important in my opinion.
As I own three shift/tilt
lenses (24, 45, 85 mm) and have used view cameras in the past I can
tell you that I was often not very happy with the outcome of
landscape pictures where I wanted to get both foreground and
background sharp. With all three lenses you have to stop down the
lens beyond f16 to achieve this “unlimited” depth of field effect
you can see on great pictures of the masters (who were using view
cameras and it has a reason why one group called themselves “f64”).
And it is still a try and error thing with the small viewfinder of
digital Dslr´s (yes also a D800/D810/D850 viewfinder is not good
enough). But the higher resolution screen of the D850 does make live
view with this lenses much more usable if you use a loupe.
The focus shift feature allows unlimited depth of field with any AF-s
lens, from super wide angle to telephoto. And after setup it is very
fast to use. With every technical solution that brings new benefits
there are also some drawbacks. Apart from controlled studio work, out
in the field wind can ruin a stacked shot, or at least you have a lot
of extra work retouching the final image. This is also a strength of
Helicon Focus as you can repair certain areas quite good with a brush
tool. So you need a stable platform (a tripod), calm conditions and a
motive which does not move too fast or better none at all.
 |
| 50 mm AF-s f1,8 @ f9, tripod, 9 shots rendered in Helicon Focus method "C" |
Here a part of the same picture rendered with Photoshop 2018CC: Specially when there is a great difference between foreground and background I got mediocre results with Photoshop.
