Friday 18 March 2011

Notes on choosing a telephoto lens

I've been using an original Sigma 70-200 f2.8 for many years. This is a
very well made lens with a metal body. It's survived years of use and
abuse. I bought it second hand when I was manic about 8 years ago and
it's served well. It has a problem caused by Canon changing their
lens-camera communication system with their digital SLRs which means it
only works at the widest aperture. Everyone knows that a lens at its
widest aperture is at its worst quality. The depth of field is tiny. I
still managed to get great photos with it. It just takes a lot more work.

It's time for an upgrade. For a years I've managed to use this lens even
though it only works at the widest aperture but now it doesn't autofocus
properly. The focus ring is hard to turn, too hard for the lens motors.
Manual focus is possible and I've used it this way but it's very
difficult. There's no ability to fine focus and because the camera's an
autofocus one there's no focusing grid in the viewfinder. It's the only
lens I've had for the last 9 months. Without my camera I am without my arm.

I follow a principle of ethical buying. It can be bloody frustrating at
times. I buy local if possible. This means buying something in the UK
when it's cheaper to get the same thing from abroad and even though the
product is from Hong Kong or China where it is originally manufactured.
I buy second hand wherever possible. Nothing new is created so there's
no use of material resources. It is a small way to contribute to
conservation and reducing the impact humans make on the planet.

I'm not strict with this but I have bought things which cost me more to
buy this way. I can usually find brand new camera equipment cheaper from
international sellers on Ebay than second hand from sellers in the UK.
For small items like batteries, memory cards and camera accessories
which I buy new I buy from international sellers. Larger items I still
try to buy with this policy of ethical buying. It is often cheaper too
but not always. There are risks involved too. For example there's no
warranty with secondhand equipment.

There's an advantage to buying second hand and buying the previous
generation of equipment. New things are usually better but not by much.
A Canon 60D is better than a Canon 50D but not by much. In fact a Canon
40D in good hands is almost as good as a 60D, Canon's latest advanced
prosumer SLR. It is incrementally better in lots of areas but the
increment is usually not worth the premium.

This effect is seen more in lenses. Digital advances rapdily but optics
doesn't. Canon tend to revise their professional lenses every decade or
so whereas their SLRs are refreshed much quicker.

This way of thinking is hard because it means forgoing the best quality
available today. Instead a practical level of high quality is possible
and the cost is significantly less. The purchases are ideally as
ethically sourced as possible. This becomes harder with the cheap price
of new goods from international sellers. I'm not sure how practical I
will be if the price difference is significant.

I also know how to use photography software. Here is where the
difference between good and great lenses becomes much smaller. Even
sharpness can be achieved in the lightroom using the Unsharp Mask filter
(and other algorithms). This is more effective on less sharp shots so
the difference in quality between good and great lenses after processing
in the lightroom is even smaller. Other tweaks in the lightroom can get
good quality shots from cheaper lenses which look like they've been shot
with better equipment.

When I say good lenses I'm talking about professional lenses. The brand
I love to buy is the Canon L-series range. I've only ever owned one and
the quality was astounding. It's in part due to their use of a compound
called Flourite. It has ultra low dispersion characteristics and allows
for excellent correction of some of the aberrations which cause problems
with other lenses. In recent times other manufacturers have caught up
and offered similar quality using alternative compounds in the lens
design. The Canon L-series are also very good quality lenses in other
respects.

The Canon 70-200mm f2.8 L is a great lens. It has been redesigned to be
even sharper and it's tough too.The f2.8 maximum aperture is important
too. It allows much more light through the lens and the extra stop of
shutter speed is really useful to pros. Cameras also work best at f2.8.
Their focusing systems are usually geared to operate at their fullest
with f2.8

The f2.8 lens has also been joined by an f4 variant. This is much
cheaper and, importantly for many people, lighter too. It has had
favourable reviews compared to the f2.8 lens though these in part may be
because the complaints about the f2.8 version have been when it was used
wide open (at the widest aperture). The f4 lens uses Flourite elements
in its construction and would show small differences in the quality of
processed images compared to the f2.8. The extra stop of light is pretty
damn useful but what's perhaps more important is the reduction in the
capability of the autofocus. It may be small or large. I don't know
because I've used f2.8 lenses for a long time. When shooting the
marathon I find a 3 frames a second a Canon 50D with a Sigma 70-200f2.8
still can't focus fast or accurately enough and I'd getiing one out of
three frames in focus at f2.8. I dot a lot of live music photography and
the extra stop is very useful as is the better capability to lock on
focus in low light.

Image Stablisation is a new technology. I've not yet tried it out
properly. The latest version on Canon's flagship telephoto zoom lens
offers 4 stops slower shutter speeds by compensating for the shaking of
the photographer's hands. I use beer to achieve this and it's pretty
useful in low light conditions. It can't compensate for subject movement
so a shot of a moving subject at 1/15s will still be blurred but the
static parts of the image will be reasonably sharp.

Is is available on the f2.8 and f4 lenses. It's a significant premium.
It's probably worth it but I've not used it.

Ultimately the decision boils down to budget. I hadn't aimed to spend a
lot on a telephoto zoom. Less than a thousand pounds on Ebay. A Canon
70-200mm f2.8 L series just ended an auction at £711 but was below the
reserve so wasn't sold. If money was no object then I'd consider it and
I'm seeing if it'll go anywhere near that price. I've seen a Canon 200mm
f2.8 L go for £250. I don't think the seller would have been happy with
that price. I wish I could have bid on it because I'd have liked to use
that lens. It's the same maximum aperture but will focus a lot quicker.
Subjective assessments say it's as good as the 70-200mm f2.8 L which I'm
surprised about. I'd expect it to be better.

The Sigma lenses are going for much less as is the Canon 70-200mm f4 L.
The 70-200 f4 is well reviewed. It's pretty close to the quality of the
f2.8 lens. It's also available new from one international business
seller for £500. The Sigma lenses are a bit of a minefield. The latest
ones would offer very good quality. There are 3 other versions between
the model I currently use and the latest one. Some of these won't work
on the latest Canon digital SLRs so it's important to check with the
seller before purchasing the lens. Less than a handful of Canon digital
SLRs work with older independent lenses because of something Canon did.

L-series optics offer a superlative quality. Camera lenses are like
champagne in that there's a house blend which establishes the marquee.
The Canon 28-70 f2.8 L which I love so much offered an unparalleled
colour and image quality with faithful reproduction of tones and
excellent resolution. The design is almost 20 years old. One has just
sold for £500. That's who good L-series optics are and their reputation
is amongst professional photographers and smart buyers who buy
secondhand gear. The very latest generation of Sigma lenses claim to
offer similar quality internal elements which used to be exclusive to
Canon L-series lenses and I'd be interested to see if these can beat the
Canon flagship telephoto zoom lenses.

Regardless, price is the factor. I want to spend most of my budget on
the standard lens. I'm set on a second hand Canon 24-70mm f2.8. While I
use a telephoto zoom a lot more than other photographers I can't justify
the price of the top of the range Canon. The f4 version offers a lot of
the quality but it loses out on one aspect: the aperture. I enjoy doing
live music photography and the extra stop of light makes a difference.
It also helps the autofocus work better (I exclusively use centre point
focusing). The additional advantage of being able to turn the lens into
a 140mm-400mm f5.6 which will still autofocus using a relatively cheap
teleconvertor means f2.8 really has a lot of value above an f4 lens.

Sigma and Tamron offer cheaper alternatives to the Canon 70-200mm f2.8
L. It is by far the best lens and with the Image Stablisation technology
it also offers a benefit for low light photographs of still subjects
handheld. The Canon is simply out of my price range unless I skimp on my
main lens or just stick to two lenses instead of a full outfit of
lenses. I still need a full frame digital camera, a fast lens and a
flash plus a battery grip, spare batteries, memory cards, a desktop
computer and a laptop.

What's great about Ebay is good products hold their price well if
they're kept in good condition. My equipment isn't but I aim to be
better at looking after it. Secondhand products depreciate a lot slower
than new ones. Good products can actually rise in price. I can get a
Sigma 70-200 and if I'm lucky I can find a secondhand version of the
latest one with Sigma's Optical Stabilisation technology. It'll still be
an expensive lens and might not have the same house style of image
rendition as the Canon but the small difference can be compensated for
with a bit more work in the Lightroom.

£500 for a fast telephoto lens might seem a lot to some people but the
possibility they offer are professional images. The image quality really
is a lot better and even with the difference possible with good editing
there's still nothing like good editing starting with a good image.
These lenses are behemoths packed with high quality glass and exotic
materials. The online price of the Canon 70-200 f2.8 L II IS new is
£1,500 and the rtail price is £2,800. The 70-200 f2.8 L MkI non-IS is
£950 online. A Sigma APO 70-200mm F2.8 EX DG OS HSM is £840 online, just
over half the price of the Canon equivalent. This is a new design and
offers what Sigma claim are the same type of lens elements as are found
in the L-series lenses.

Price makes the choice much more difficult. The flagship Canon lenses
are also weather proof and dust proof which means they can be used when
other lenses can't. I don't do much press work but I like to be able to
shoot in the rain. In practice the original Sigma 70-200mm f2.8 can
survive a little bit of water but is best kept out of the rain.

If I set my budget at £500 then it's between the Canon f4 L and the
Sigma or Tamron f2.8 from an earlier generation, one without the quality
of the L-series f4.

If my budget was £1000 I could get the latest Sigma f2.8 with Optical
Stabilisation, a Canon f4 with Image Stablisation or a Canon MkI f2.8
telezoom.

For £1,500 I could get Canon's flagship lens, one which is beloved by
professionals. It's got everything and is class-leading. It is very well
built and featured. The image quality will be exceptional especially
wide open which is where I often end up.

I'm spending a large amount of money on my standard lens so it's not
possible for me to stretch all the way to a Sigma f2.8 OS but I think
this is the best value option offering much of the quality of the Canon
with similar features at a fraction the price.

For many people the Canon f4 L-series lens is the best bargain. It
offers close to the quality and build of their flagship models and can
be purchased for about £500 without IS. It's just not f2.8 though and an
older non-IS Sigma is less secondhand. The Canon f4 will offer better
image quality out of the box but it can't shoot at f2.8, it doesn't
offer the best for camera autofocus systems and the largest
teleconvertor which can be used and it still retains autofocus is 1.4x
not 2x.

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We It comes in part from an appreciation that no one can truly sign their own work. Everything is many influences coming together to the one moment where a work exists. The other is a begrudging acceptance that my work was never my own. There is another consciousness or non-corporeal entity that helps and harms me in everything I do. I am not I because of this force or entity. I am "we"