Recently bought a Coolpix P900, love it.
We also have a DSLR.
Looking at getting something with similar 'zoom' i've found myself a bit
The P900 is a 24-2000mm equivalent (I haven't got my head around that
yet) but it seems the the lens is 4.3-357mm.
If I was to buy a lens for the DSLR would I be looking for 2000mm or
Depends on the size of the image sensor in the DSLR. If its a true 35mm
sensor, then you would need a 2000mm lens. If its the more common APS
sized sensor then you get a magnification factor because the sensor
crops the edges of the frame. The factor is typically about 1.4 to 1.6x,
so you would need a lens in the 1200 - 1400mm range to get the same effect.
However for lenses that long, be prepared to pay an eye watering amount
if you want anything of decent quality and also adequate aperture to
actually let any light into it!
The difference is because the target size is different. Measure the view
angle you get with the P900 and then choose a lens designed for the DSLR
with the same view angle. If the vendors of the lenses don't quote it
google lens conversion table or something.
P900 sensor is (only) 6.2 x 4.6 mm compared to 22.2 x 14.8 for Canon APS-C.
So the factor is about 3.5 and you will need a 1200 mm lens for a Canon
APS-C DSLR for the same telephoto view.
You won't of course get an 83:1 zoom ratio on a DSLR. The convenience of
such a thing as found on a superzoom compact (or camcorder) comes at the
price of quality.
Check out professional sports photographers and you will see that they
carry several cameras with different lenses (often zoom, but the zoom
ratio is seldom more than about 4:1).
In article ,
From the early days of TV, lenses were always quoted as viewing angle - as
different types of cameras had different target sizes. Never did
understand why this wasn't done with photo lenses too. Even on the rare
occasion where a lens will fit more than one type of camera.
Lenses still get quoted in '35mmm film equivalent'
Obviously a tiny CCD and a tiny lens will have the same angle of
coverage as a much bigger lens and film area.
You will need a tripod or serious software to prevent [effects of] shake
at 2000mm equivalent
It *is* done, effectively, in that most cameras quote the 35-equivalent
focal length of the lens, as well as the actual focal length. At least then
you can compare lenses for different cameras by comparing their
35-equivalent focal lengths.
And you'll probably find that image-stabilisation, while good, doesn't work
as well as the manufacturers claim - it is good but not perfect.
The thing I didn't realise about image stabilisation is that it can actually
produce a *less* sharp picture if the camera is held rock-steady on a
tripod: I found this when taking some night-time (ie 10 second exposure)
photos with my compact camera, until I worked out in the menu how to turn
off IS. On my DSLR it was easy: there was a big IS on/off switch on the
In article ,
But how many lenses can be fitted to cameras with different target sizes?
Not saying you wouldn't give the actual focal lenght too - but stating the
angle of view for each target size camera the lens would fit to wouldn't
In other words, if the norm was to state the angle of view, you'd know
what to expect with that in use. Across all platforms. Those who wanted to
know the actual focal lenght could look it up.
You'd need to standardise on which dimension you were referring to:
horizontal, vertical or diagonal. Probably best to use diagonal then a) you
are using the same convention as when specifying screen sizes for TVs and
laptops, b) you don't have the added confusion that the long axis is
vertical in a portrait picture and horizontal in a landscape picture.
I suppose you've got the added problem that the numbers would probably
involve fractions of a degree so these may need to be marked on the lens
barrel - unless you round to the nearest degree.
Was it only for TV work that lenses quoted in angles were used? In 16mm and
35mm movie and 35mm still, lenses are usually referred to as actual focal
length. (NB: 35 mm movie and 35 mm still are different size frames: 18x24
for movie and 24x36 for still, because the film runs vertically in movie and
horizontally in still, so the distance between perforations is the long axis
in one and the short axis in the other)
The Natural Philosopher wrote in news:oct9qg$2k6$1
The user would know if the lens that matched his camera / sensor has a
particular view angle and from that be able to imagine the field of view
that would be achieved.
In article ,
The reason angle of view was used in TV in the early days was there were
different types of electronic camera in use. And someone planning say a
drama wouldn't always know which studio he's get and therefore which type
of camera. So he could work out is shots on paper using angle, and leave
it to others to make sure the correct lenses were fitted to the
appropriate camera - long before the days of zoom lenses being the norm.
IIRC, the standard lenses on a studio TV camera turret in those days were
a 35, 24, 16 and 8 degree.
In article ,
Does anyone know or care what focal lenght lens is fitted to their phone?
But they will be more aware of its angle of view, through using it. Same
as with any camera. Which is why, to me, it is the more important thing to