qqq features moniiksgire and vlieland and eider tessel qqq

Reach (bereik) is by far the most important, never quantified and rather undefined factor in bird photography. Ask anybody! Reach (bereik) depends on several factors and an usable definition we developed really works for us every day in the field. This is also the reason why we in this blog always report distance to bird and 35 mm equivalent (35 mm equivalent). In our view this is quite relevant. Once you understand and can quantify what your reach (bereik) in borderline situations really is you can rather decide than quess whether to make a certain shot or not and use the required settings or equipment to get the optimal result when you ppress the release button.

Our “working definition” of reach (bereik) is:

Reach (bereik), calculated in meters, is the amount in Megapixels, of sufficiently resolved detail, per square millimeter in the uncropped digital image of the photographed bird.

This implies that reach (bereik) is dependant – “a function of” – the following factors to the extent defined in parentheses below:

• 35mm equivalent of used equipment in millimeters (squarely proportional)
• resolution of sensor in Mpixels per square millimeter (proportional)
• distance camera-bird in meters (inverted square proportional)
• amount of available light (some factor 0-100%)
• quality of atmosphere (some factor 0-100%)
• size (“size” in centimeters in ANWB Bird Guide or other Guide or other)
• subjective personal judgement of “sufficiently resolved”: We shall define this using a benchmark-photo of a Great Spotted Woodpecker (Grote Bonte Specht) at a distance of 10 meters using a combination tripod D800 Nikkor 300mm f/3D non VR. This is our benchmark for, in what we consideras being, “sufficiently resolved” in bird photography.

35mm equivalent = focus distance (mm) x magnification factor converter x crop factor camera (mm).

For example: 35mm equivalent of D500 NIkkor 500mm f/5.6E PF VR TC-14E = 500 x 1.4 x 1.5 = 1050mm.

Note that REACH is also dependant on the size of the subject bird you are photographing. A Wren (Winterkoning) needs to be pretty close like 5 meters to produce an acceptable detailed picture. On the contrary: a Grey Heron (Blauwe Reiger) could be at 50 meters and yet produce a very fine picture.

You have to develop a good understanding of what your actual reach (bereik) in meters of your equipment in different situations is when photographing different species of birds in varying circumstances at a certain distance. You definitely need this ready qqq knowledge when you buy or choose your equipment.You need it also in the field to deciding to yes or no photograph a certain bird giving distance, available light, your current equipment (and settings!), etcetera. Quantification of reach (bereik) may seem a difficult subject- and it really is! – but it is one of the keys to succesful lightweight photography. Be warned that many some photographers and even sales people or “experts” in fact even don’t have the foggiest of what quantified reach is.

One could express it in a formula as follows: reach (in meters) R = R (35mm equivalent, size bird, distance, available light, qualityof atmosphere),

Reach is square (!) proportional to the so-called 35-mm equivalent of the camera-lens-converter combination.

The 35mm equivalent = focus distance (mm) X converter factor (1.4, 1.7, 2.0) X crop factor (1.5, 2.7 Nikon camera’s, 2.0 Panasonic camera’s)

In practice this means that for instance a picture of a Great Spotted Woodpecker at 14 meters has only half the amount of detail (resolved pixels) of a picture taken with the same combination at 10 meters (1.4 x 1.4 = 1.96), at 17 meters you get 33% and at 20 meters only a skinny 25% detail is left. Bad news!

If you invert this rule you can conclude that, going from 500mm to 700mm by using a 1.4 converter on a 500mm lens, you achieve a 1050 mm 35mm equivalent and this you could consider to be very good news! (At a loss of 1 stop light though).

---

Some examples of pictures with rather small, average or quite large reach (bereik) to demonstrate the use of this working definition of reach (bereik) in the field> they could show yoou how to quantify your chances on sufficiently detailed pictures in different circumstances using different equipment by applying these “quadratic rules” in the field:

---

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

•