Pixiq

I bet that most people these days come to wide-angle photography via the short-focus end of the ubiquitous, all-purpose zoom whether on an SLR, compact or prosumer camera. 

With wide angles there's always a sense of a  quest, a sort of holy grail where, in my mind's eye, I have the kind of image I want to achieve and then have to find the hardware to do it. The question is will ultra-wide zooms give those close-ups with impact: the answer is a qualified 'affirmative'.

Many zooms sport a ‘macro' setting but it functions at the long end of the zoom range and is really just a 'close-up' mode in spite of the name 'macro' emblazoned on its barrel. The ‘macro’ mode began in the early days of zooms for the masses, rather than them being specialist opitcs on an Arriflex cine camera. To function, any zoom must move groups of lenses internally, relative to one another via a series of cams and threads…fix a group and you get a ‘macro mode as a happy accident. In practice it is a bit more sophisticated than this but you get the idea. To sell these lenses the word ‘macro’ became the catch all and the abuse of the word term began to make it a general term for getting close.

On a good quality zoom this ‘macro’ feature is useful but its not what I am looking for here. A fact of life with all zooms is that they are a compromise – complexity of design makes sure of that and we ask miracles of them. One of the things it is hard to design is a distortion-free close-focus capability…this does not matter with a rectangular fisheye (all to be revealed in the next post) and they offer a much better close-focus than most zooms.

If you wander through tables of lens specs until you get bug-eyed, you’ll see that those wide-angle zooms offering the best close-focus tend to be the ones with the least ambitious zoom range maybe a 2x capability at most.

So. Let’s take a quick look at three of these: the first two are FX lenses, the last a DX design.

NB In what follows, 

• The biggest reproduction ratio (maximum magnification) is always at the longer focal length end
• Closet focus distance is measured from the sensor (it used to be film-plane) to subject. So, to get the distance from the front lens element subtract from this the physical length of the lens plus how far the sensor is behind the lens mount.

Nikon has the 14-24mm f/2.8G ED AF-S NIKKOR a superb lens and one already covered in detail in a pixiq post by Michael Freeman. Its closest focus is  0.28m and repro ratio 1/6.7 (x 0.15 max magnfication)

 Canon’s EF 16-35mm f/2.8 L II USM  also has a closest focus of 28cm repro ratio of 1:4.5  (x 0.22 magnification). This is a lens of legendary quality of the results it produces throughout its range are breath taking. A fortunate friend has one and gloats… Canon also provide data for its use with an extension tube (both these tubes are fully auto – wake up Nikon) and this makes it unbeatable for wide-angle macro photography. Yes, you’ll be very close with a tube fitted …and lighting is tricky but a fantastic capability is there.

        Addition of...                             Magnification range

I went digital with Nikon equipment simply because of the backward compatibility with lenses of which I had a fair collection. Time and again I find myself questioning the wisdom of that decision when I see some amazing Canon lenses… 

Sigma 10-20mm f/4-5.6 EX DC HSM lens. This is one of Sigma's digital lenses able to fill a DX sensor but which would vignette to some extent at the wide end on FX.

I have had a very good relationship with Sigma (UK) for many years – I have borrowed lenses, tested them in the field and written an honest appraisal. If I decide I cannot live without the lens then I buy it.

This objective has a closest focus of 24 cm from the sensor – which means 11cm from the front element with a maximum magnification at the 20mm end of 1/6.7 (0.15 x). For subjects such as alpine plants in the landscape it is fantastic - extremely sharp and I can never believe how much detail there is – just for devilment I sometimes examine files at 200% in Lightroom and Photoshop, a VERY unfair test but … that balance of price and quality gets me every time.

At open apertures (where I hardly ever shoot) there is slight light fall off at the edges but that disappears as you stop down. The build quality is very good, zoom action smooth and manual focus precise: autofocus is whisper quiet and fast

Sigma have also introduced a fixed max aperture lens 
10-20mm f/3.5 EX DC HSM with the same close focus and max reproduction ratio.There is also an older FX  design their 12-24mm f/4.5-5.6 EX DG ASPHERICAL HSM which is highly rated in reviews and by friends who have them: closest focus 28cm max reproduction 1:7.1

I would love to be able to use an extension tube with the Sigma 10-20mm f/4-5.6 but, as with so many DX lenses, there is no manual diaphragm. No doubt, one could do something with a bit of blu-tac™ or tape on the diaphragm pin but...its a case of "kids, do not try this one at home!" However, a few experiments in the studio have revealed that at the 10mm end for this zoom, the closest focus is behind the front lens element – so, not a lot of practical use there.

How do these ultra-wide zooms compare with a more general zoom lens boasting a decent wide end?

Last year I bought a Nikon 16-85mm f/3.5-5.6G ED VR lens. It seemed useful for general work but it was mainly because I wanted to travel light to the UK after the birth of my grand daughter Tallulah – yes, she was tiny but no macro subject!

The closest focus at 16mm is just 0.38m from the sensor (about 25cm from lens front). This serves well for larger plants or those smaller subjects if I zoom in...but then I lose the wide view.

To sum up: In practice, the best close-focus performance belongs to those lenses with the shortest zoom range eg. 10-20mm, 12-24mm, 16-35mm. These are all effectively 2x zooms. And Canon users… you win hands down.

Don't get me wrong, I am very happy with the Sigma 10-20mm zoom - it is a fabulous optic and for modest sized groups of flowers it delivers just the effect I want. But I am greedy and want to move in on smaller bugs...there is a danger that they will get lost in the frame with all of these zooms except the Canon with its extension tubes..

However, as I shall reveal in the next post there is a way of getting closer (and not changing systems) using rectangular fisheyes. On DX format  these have hardly any curvature at the edges of the field of view and become very close-focusing ultra-wides….

And last but not least...the bugs and fungi  were photographed on the patch of wild ground we dare to call a garden.. the oyster fungi appeared on our log pile. Working close to home is great for experimenting (you can get back to the screen quickly to check whether you have got it right). It is also a way of becoming really tuned to what is around you..see Close-up and Close to home, 

Check out Wide-angle macro Part 1 - close ups with impact and

Wide-angle macro Part  3... rectangular fisheyes