FZ1000 Getting Sharp Pictures at the Long End of the zoom

Plenty of structures here for the AF to see.  Handheld.

 

When I startedmaking pictures with the FZ1000, I noticed that quite a few shots taken at the long end of the zoom were not quite sharp.

I carried out systematic chart testing of the lens at all focal lengths and discovered that the lens is not quite as sharp at E400mm as it is at shorter focal lengths but it is still very good and should be capable of making convincingly sharp photographs.

I noticed that some of my pictures at E400mm looked impressively sharp when printed at 400x600mm in size while others were only fit for the trash bin.

I had previously had very much the same issues with the Lumix 100-300mm lens (E200-600mm) on Micro Four Thirds and the long end of the E25-600mm lens on the Panasonic FZ200.

Shot handheld from a moving ferry. Moderate wind, sunny afternoon.  Notice the wavy line atmospheric distortion seen on balcony railings and similar. No lens on earth could make a properly sharp photo in this situation.

 

What's going on?  I think the same issues apply to each of these lenses at the long end.

1. If some pictures are convincingly sharp and others are not the problem is most likely either

a) focus variation or

b) user technique  variation or

c) subject variation

I have come to the view that all three factors are in play.

2. The lens loses local contrast (a.k.a. microcontrast) as it is zoomed out. I can easily see this in my test chart photos. In addition in each case there is slight loss of resolution.

3. Due to the above, the camera's contrast  detect  autofocus  system  has more difficulty achieving focus at the long end.

4. The effect of camera shake is progressively magnified towards  the long end and this is not fully compensated by OIS, even the excellent 5 axis type in the FZ1000.

My impression is that OIS is very good for compensating relatively slow shake cycles but not so effective for compensating the fast cycles which are a significant cause of unsharpness due to camera shake with very long lenses.

5. I have noticed that the problem of intermittent unsharpness is most apparent with subjects at a long distance from the camera.

6. Observation of photos taken at long distance clearly shows the deleterious effects of haze and  atmospheric distortion. The latter is a phenomenon caused by swirling air currents within which the refractive index of the air varies enough to affect photographs, sometimes to a marked degree.

7.  Both the above factors make the task of the contrast detect AF system even more difficult.

In response to  the above observations and impressions I have worked out a set of guidelines for improving sharpness at the long end of the zoom.

Settings 

Mode Dial S with shutter speed at 1/400sec or faster for static subjects, 1/800 sec or faster for moving subjects.  This will usually see the aperture at f4.   OR

Mode Dial M with aperture at f5 or f5.6 and shutter speed as above, Auto ISO in each case.

This can be useful for static subjects as the lens performs slightly better at f5 than f4.  For moving subjects combatting shutter shake and achieving accurate focus are more important.

Focus Mode  AFS  or Manual with peaking for static subjects, AFC for moving subjects. Manual focus works best on tripod as the camera needs to be reasonably still to enable viewing of the enlarged image with peaking.

Autofocus Mode 1 Area, AF box sized to match the subject but larger = more sensitive, smaller = more precise. I usually have the box at around size 5/15 counting up from the smallest.

Shutter type, mechanical.  The FZ1000 does not have a shutter shock problem so the mechanical shutter is OK.

Technique

Hand Held:  

Stand, sit or lie comfortably and relaxed.

Look through  the EVF with the camera steadily braced against the skull bones.

Practice breathing technique. Mini meditate to slow the heart rate and  reduce muscle tremor. Squeeze the shutter button just at the end of a slow exhalation.

Place the AF box over a part of the subject which is reasonably light in tone, has good contrast and if possible has strong vertical lines (camera in landscape orientation). Note that Panasonic AF (and possibly others, I don't know) will not focus on a non textured subject with lines running only horizontally.

Make the box as large as possible without extending outside the main subject so focus on the background is prevented.

Tripod:

Use Timer 2 sec or remote shutter release.

Lowest possible ISO for the conditions.

Manual focus where possible.

 

Subject  For distant subjects try to photograph on a day with low air pollution and low haze. In most locations some seasons/wind directions are usually better than others.

Try to have the subject in cross lighting for maximum definition.

Early mornings usually see the least air turbulence of the day.

Summary  The FZ1000 can make very good or just mediocre photos at the long end of the zoom. In most cases good results can be attributed to correct settings, subject selection and optimal technique.  

I have taken my own advice and the  results are improving.