© Copyright Khen Lim, 2013. All Rights Reserved.

see also:

• a history of the Micro Four Thirds camera system part I - overview
• a history of Micro Four Thirds part II - mirrorless cameras
• a history of Micro Four Thirds part III - the Micro FourThirds system
• a history of Micro Four Thirds part IV - the Olympus cameras in detail
• a history of Micro Four Thirds part V - the E7 dSLR and the potential end of further development of the Four Thirds system
• a history of Micro Four Thirds part VI - predicting the future
• a history of Micro Four Thirds part VIII - timeline of cameras and lenses
• a history of Micro Four Thirds part IX - Third Party options
• when wisdom matures - the Olympus E-M1 by Khen Lim
• a catalogue of Micro Four Thirds lenses
• photography and camping main index page
• contributions by Khen Lim

Image courtesy of Olympus Imaging Corporation

The M.Zuiko Digital is the name given to Olympus’ second concurrently running range of lenses. The ‘M’ fixture stands for ‘Mirrorless’ to denote its exclusive compatibility to the company’s series of Micro FourThirds cameras that do not feature an internal reflex mirror.

Unlike its larger siblings – the Zuiko Digital – there does not appear to be a distinct grouping of different lenses based on their optical performance. Rather what we can see so far is the usual prime and zoom separations and within them, the groupings based on different focal length coverage. With the FourThirds system, the lenses were three-fold. The normal range does not have a name but the upper two are called High Grade (HG) and Super High Grade (SHG). It is obvious how these three are distinctly different although in most cases, even the HG is plentiful enough for serious work let alone the SHG. As for the ‘normal’ lenses, Olympus’ reputation for optical superiority suggests that they are not exactly very normal either – their performance is usually competitive enough against its immediate and costlier competitors.

The M.Zuiko Digital range today does not appear to be officially grouped but we can see some distinctions. It is clear that from the beginning, Olympus’ intention was to appeal to the broad masses and they did this by developing mainly zoom lenses that were compact and light in order to match the promises of Micro FourThirds. We see the company introducing these lenses continuously during the initial stages. Later on they began launching fast and bright prime lenses that brought into sharp focus the ability of Micro FourThirds to deliver very high performance lenses that were as scintillating as they were light and pocketable. While this second run continues as Olympus introduces even more primes to fill the gaps, the third wave is about to begin. This is where we will see fast and serious zoom lenses emerging. And with all three put into place, we can begin to see the company’s vision crystallising as a single collective.

The new Zuiko Extra-low Reflection Optical coating or ZERO in short Images courtesy of Olympus Imaging Corporation

Along the way Olympus quietly introduced some of the more stunning technologies centring on the Z.E.R.O. coating but even before that, there was the MSC technology that in itself was also exemplary of its natural ability to innovate. MSC – short for Movie & Still Compatible – is a lens technology that centres on the use of a high-precision screw driven mechanism powered by a high-speed drive motor featuring a precision-controlled stop-start system and managed by guide shafts that offer micron-fine tolerances. To help this along, an MSC lens also features low focusing optical mass so that very fast moving speeds and precision can both be achieved simultaneously. The illustration below shows how this lower mass is deployed in the mirrorless-based ED 9-18mm f4.0-5.6 (below right) compared to its namesake in the FourThirds system (below left):

Olympus’ Movie & Still Compatible (MSC) mechanical components Illustrations courtesy of Olympus Imaging Corporation

With lenses like the ED 9-18mm and the ED 14-42mm, the MSC mechanism deploys one low-mass optical element to do the focusing. In lenses with wider zoom coverage such as the ED 14-150mm, two elements are used but even so, the net mass is very low.

While MSC broke through with faster – and quieter – autofocusing, it was ZERO that help separate Olympus optical standards from the others. As we can see with the 12mm f2.0 (the first to incorporate ZERO technology), the standards were so high that DxO remarked that its performance was competitive even against an equivalent high-performance prime lens attached to a leading competitor’s APS-C DSLR (Canon EOS 5D Mk II). Short for Zuiko Extra(-low) Reflectance Optical, ZERO coating delivers an ever higher level of image contrast and sharpness by reducing reflectance at the 450-650mm wavelength by 50 percent while at the same time minimising ghosting and lens flare particularly when shooting against the light. Olympus uses a unique vacuum evaporation process that results in a strong optical coating that also has a hardened resistance against scratching so that its multicoated surface can stand the test of time better than otherwise.

When Olympus unveiled the first of its mirrorless incarnations – the Pen E-P1 – the wonder lens was not a zoom but a prime lens. The M.Zuiko Digital 17mm f2.8 appeared tiny but there was also the standard zoom 14-42mm f3.5-5.6 with its unique collapsible feature. The 17mm f2.8 is referred to in the industry as a ‘pancake’ lens basically because it was thin enough to resemble one but before we all think this is a digital innovation, it isn’t. Pancake lenses made their name during the film days. Both Olympus and Pentax were particularly at the forefront with this lens design but with recent advances in optical technologies, the pancake lenses we’re seeing now are even thinner.

M.Zuiko Digital 17mm f2.8 (chrome version only) Image courtesy of Olympus Imaging Corporation

The 17mm f2.8 lens has the 35mm film equivalent focal length of 34mm, making it an ideal standard-wide lens. In other words it is neither too restrictive nor too widely distorted. At 34-35mm or anywhere up to 40mm, linear distortion is very much under control. Yet you still have a degree of spatiality that is pleasant to use. Despite how compact (22mm length) and light (71 grams) the lens is, there are nine elements packed in six groups and amongst these, there is a DSA element, an HR element and two aspheric lenses.

The original M.Zuiko Digital ED 14-42mm f3.5-5.6 in chrome (left) and black (right) versions in collapsed configuration Images courtesy of Olympus Imaging Corporation

The ED 14-42mm f3.5-5.6 was apparently based on the larger FourThirds original lens. That may or may not be true – the fact that they share the same basic spec doesn’t always mean so. In fact the two just don’t even look anywhere alike. Its optical brightness suggests that the 14-42mm lens is no big beast and despite having a DSA as well as an aspheric and ED element, it weighs in at only 150 grams. It is appreciably compact already but with its novel collapsible feature, it can be made even smaller when not in use. Olympus built into the lens the ability to retract the barrel into a parking position, contracting its length down to only 43.5 millimetres. By comparison to its FourThirds sibling, the mirrorless version is some 35 percent smaller in volume and only 80 percent of its weight.

At an equivalent of 28-84mm coverage, Olympus’ first standard zoom lens for its mirrorless cameras has a good average reach. Wideangle was usable and at 84mm, it’s ideal for portraitures but at a maximum aperture of f5.6, it wasn’t going to win accolades for bokeh or brightness. At 0.24X, it has slightly better magnification and works off a minimum focusing distance of 0.25 metre. The 17mm gets closer at 0.2 metre but magnification is only at 0.11X.

There’s not much to really choose from between these two lenses other than a straight choice of focal length – one is a lightweight prime lens meant for everyday use and the other is a generic zoom lens for general use. In practical terms for the average user, the ED 14-42mm would win hands down simply because it’s a zoom. On the other hand for those who like a budget-priced prime for handling the occasional lowlight condition, the 17mm f2.8 is hard to beat. Both are easy to handle and won’t break the bank balance. In the case of the pancake lens, Olympus also brought out the VF-1 external optical viewfinder that matches its field of view, making it a good accessory for those who prefer to use the E-P1 with a viewfinder. In image quality terms, both deliver what the average user is looking for although either won’t raise any eyebrows for the more pernickety. But as far as being the ideal introduction lenses for Olympus’ first mirrorless camera, the Pen E-P1, these two are as close to ideal as one could get.

Almost half a year later, two more lenses joined the M.Zuiko Digital range. They were the ED 9-18mm f4-5.6 and the ED 14-150mm f4-5.6. On the same day that both were launched, Olympus brought out their first Pen Lite model, the E-PL1. Interestingly too, it was only three months after the E-P2 was released.

M.Zuiko Digital ED 9-18mm f4-5.6 (black version only) Image courtesy of Olympus Imaging Corporation

Both the ED 9-18mm and 14-150mm were the first to incorporate the MSC technology and appreciably, their autofocusing performance was visibly better. MSC however was not something that could be updated via firmware; therefore those who purchased the earlier ED 14-42mm and/or the pancake 17mm lens couldn’t benefit from this new advancement. However MSC’s biggest advantage is more likely to be appreciated by those who are into moviemaking rather than still photography.

The ED 9-18mm obviously has a namesake in the FourThirds lens offering but again, they’re not identical otherwise. This one in particular happens to be the first in the range to showcase Olympus’ MSC technology, which makes it particularly suited to movie shooting because of its quieter autofocusing mechanism. A comparison between the two reveals the advantages of the Micro FourThirds format. Despite sharing the use of the same FourThirds sensor, the mirrorless version lens is substantially smaller and far more pocketable.

M.Zuiko Digital ED 14-150mm f4-5.6 (black version only) Image courtesy of Olympus Imaging Corporation

The ED 14-150mm on the other hand is a new lens with a remarkable reach. The 10.7X zoom lens covers the equivalent of 28mm wide-angle to a very useful 300mm telephoto but like the ED 9-18mm, it’s on the slower side with a variable aperture opening of f4 to f5.6. However it is very compact; in fact it is the smallest of its type in the world with a length of 83 millimetres and weighing at 280 grams, it is very easy to handle. While its close-focusing capabilities may be nothing to shout at, its zoom range assures a high degree of usefulness especially if you keep things outdoors in broad daylight.

In seven months’ time came two more lenses as Olympus worked hard at developing its line-up to meet mainstream requirements. So far it was clear that the company was emphasising zoom lenses – there were now three zooms and one prime covering a range of 9mm to 150mm, which in 35mm film terms, stretches from 18mm ultrawide angle to telephoto. On August 31 2010, Olympus pushed the upper limits to twice the length, introducing the ED 75-300mm f4.8-6.7, taking the maximum focal length to a film equivalent of 600mm. As for the other lens, the standard 14-42mm lens (launched a little more than a year ago) was now joined by its companion 40-150mm f4-5.6. By this point, both the lenses had cemented the company’s permanent use of the MSC technology.

(left to right) M.Zuiko Digital ED 40-150mm f4-5.6 in black and chrome versions and the original ED 75-300mm f4.8-6.7 in black and chrome versions also Images courtesy of Olympus Imaging Corporation

The ED 40-150mm lens is understood to be a loose adaptation of the FourThirds equivalent. Like the companion 14-42mm, this was a staple lens for Olympus users that till today continues to sell like hotcakes through its shelf life essentially as a twin-lens kit. With all the ‘M’ lenses so far, the 40-150mm is light and compact. At 190 grams, it’s only 40 grams heavier than the 14-42mm but at 86 millimetres, it is surprisingly longer than the 14-150mm by 3 millimetres.

Rated at f4.8-6.7, the ED 75-300mm is not exactly a very bright lens but the benefits are more physical than photographical. At a weight of 430 grams, it may be the heaviest of lenses that Olympus has so far produced for its Pen range but it is the lightest lens to offer a film equivalent of 600mm telephoto focal length. It also happens to be the world’s smallest by a fair margin given that it only measures 116 millimetres in length.

With the Pen E-PL2 due for an early 2011 arrival (January 6), Olympus decided to upgrade its all-important standard zoom, the 14-42mm. Important changes were in store. Although the lens was made a not-insignificant 38 grams lighter (now at 112 grams), it was on the other hand physically longer, extending by a manageable 6 millimetre to 50mm. Minimum focusing distance remains untouched; however an image magnification of 0.19X meant that it suffered in the upgrade (the earlier version as 0.24X). All of these physical changes are made to accommodate a revised optical design within.

The updated M.Zuiko Digital 14-42mm f3.5-5.6 II with MSC certification Images courtesy of Olympus Imaging Corporation

The earlier ED (Extra-low Dispersion) element was also sacrificed to make way for the MSC system, brought on board to benefit movie shooters looking for quieter and slightly faster autofocusing.

Thankfully the original collapsible body design was retained. At any rate it didn’t look like many took much notice of the slight physical degradation of the revised standard zoom lens now referred to as 14-42mm II (without the ‘ED’) especially when the E-PL2 took much of the attention during the introduction.

Six months into the brand new year and Olympus was clearly on a roll. There was much excitement in the air when on June 30 2011 the company unleashed a storm of surprises. Apart from the three new Pen models signalling its third generation (E-P3, E-PL3 and E-PM1), there were also four lenses on show. Two were styling revisions of existing lenses (14-42mm II R and 40-150mm R) but the other two were astonishing enough to take the market by complete surprise. It is fair to say that most had not expected the new 45mm f1.8 and ED 12mm f2.0 prime lenses.

The cosmetically cleaned-up M.Zuiko Digital pairing of 14-42mm f3.5-5.6 II R and 40-150mm f4-5.6 R Images courtesy of Olympus Imaging Corporation

In line with the company’s forward-moving design direction, the dual kit lenses were brought in for a cosmetic revamp that saw changes primarily to the zoom ring grip surface pattern but also to the adoption of a slightly different barrel colour in order to better match the revised chrome look that Olympus has now intended to adopt. All of these account for the adding of the ‘R’ label to the two lenses. Technically and optically, both perform identically to their immediate predecessors with no changes. Hence the 14-42mm II became 14-42mm II R while the 40-150mm simply became known as the 40-150mm R since there was no earlier upgrades prior.

The limited black edition M.Zuiko Digital ED 12mm f2.0 seen here with and without the optional lens hood and the original chrome version Image courtesy of Olympus Imaging Corporation

The big news was however reserved for the two outstanding fast primes, reliving warm and fond memories for all Olympus fans including users of the company’s past-generation OM cameras and lenses. The ED 12mm f2.0 simply translates into a very impressive super-wide 24mm at a bright f2 aperture, making it not only very versatile but given its new Z.E.R.O. (Zuiko Extra(-low) Reflectance Optical) coating technology, its performance potential was enormous. Immediately upon its release, there was an unusually significant clamouring for the lens for reviews. On the Internet, rave reviews were par for the course – expectations were higher than normal and in more ways than one, it overshadowed even the new Pen E-P3, which in itself was not an insignificant model with revolutionary performance upgrades.

None of the online reviews of the 12mm were more influential than DP Review’s preview notes but the most influential test results came from DxO Mark, which measured the lens and found it to resolve better than Canon’s vaunted EF-L 12mm used on the EOS 5D Mark II APS-C DSLR camera. This bit of news was like a seal of approval for many but those who already knew of Olympus’ optical traditions merely understood this as a signal for the return of the company to the highest ranks in the industry and what better way to show this than to introduce a truly outstanding piece of glass.

The 12mm f2.0 was not only optically impressive; it was built differently to any past ‘M’ lenses up to that point. Unlike the others, this one not only had a metal body but it also featured an unusual but highly useful Snap-Focus feature, which enable the lens to switch instantaneously from AF to MF mode without resorting to menu changes from within the camera. All you have to do is to pull the lens ring back towards the camera to reveal the focusing scale and DOF markings. Once in place, the ring can then be used to focus manually. Movement was fluid and very well weighted – feelings of the OM Zuiko lenses were all coming alive for those who have been waiting for this day to take place. Within less than a year, Olympus teased the market by offering a limited-edition black version of the 12mm f2.0 in order to match the black-bodied E-M5. Production numbers were limited, as expected, but the price was also higher much to the chagrin of many.

The black and chrome versions of the M.Zuiko Digital 45mm f1.8 Note: Hood shown attached to the chrome version is optional Images courtesy of Olympus Imaging Corporation

The 45mm f1.8 was not to be shaded even if the 12mm f2 took the honours for many. Like the super-wide, this portraiture-optimised lens is metal bodied. At a film equivalent of 90mm, optical performance at a fully opened f1.8 produced awesome defocusing effects that drew equally incredible reviews throughout the Internet. Like the 12mm, the metal construction and optical specifications make for a solid 116 gram feel and in one’s hand, it certainly gives that assurance. The 12mm might have stolen much of the show but the 45mm f1.8 holds its own. Especially when it comes to pricing, it was far more affordable but it doesn’t lack in any way whatsoever when it comes to specifications. The pricing was so good that for many who later purchased the E-M5, the 45mm f1.8 was almost certainly bought at the same time or eventually added to their system.

With news that a ‘new’ Micro FourThirds camera was just around the corner – one that was different from what we’ve been seeing so far – Olympus then decided to pre-announce another lens. As far as lenses go, the ED 12-50mm was not just unusual but different in many ways. Many were hoping for a pro-grade standard zoom lens but by the word ‘pro,’ the expectations were for it to be optically fast and bright. At f3.5-6.3, the disappointment was palpable but that was only on paper. Once the 12-50mm was made available together with the E-M5 two months later, the disappointment largely evaporated as users were able to see for themselves that the performance remained very usable and tractable.

The black and chrome versions of the M.Zuiko Digital ED 12-50mm f3.5-6.3 EZ Images courtesy of Olympus Imaging Corporation

A few things set this lens apart from Olympus’ earlier zoom efforts. Firstly this was the company’s first weatherproof ‘M’ lens. Whether this meant that the 12-50mm was a ‘pro’ lens remains questionable even up to today as the company has not issued any directives to call it that and neither has it released an official ‘pro’ lens yet. In other words even the legendary 12mm f2.0 was not labelled as such as you don’t see such claims on their many websites including the official FourThirds organisation site at www.four-thirds.org. Being weatherproof of course makes it extremely adaptable and usable in far more conditions than any of the other ‘M’ lenses – serious users at least could appreciate this to a large degree.

Secondly this is the first ‘M’ lens to embrace the ‘EZ’ label. ‘EZ’ doesn’t mean ‘easy’; rather it refers to ‘Electric Zoom,’ which means the ED 12-50mm is endowed with a built-in micro-motion motorised function that enables the lens to offer the same slow but smooth zooming that video shooters prefer. In other words there is no need to teach yourself how to move the zoom ring in a pained slow motion (not a small feat in itself) – just shift the zoom ring back to the right step and the ring can then rely on the internal motor to move the zoom back and forth.

Thirdly Olympus built into the ED 12-50mm an excellent close-focusing capability; certainly the best there is by far of all the lenses in the company’s range. At 0.35 metre, you enjoy 0.72X magnification – both attributes produce outstanding resolution, making full use of the lens’ optical capabilities to the hilt and adding yet another feature to its bow.

All these of course mean this is not a lightweight lens; certainly all the way south of the 17mm pancake but even so, 211 grams is a small price to pay for a lens with this range of capabilities and proven results to boot. If a comparison is necessary, putting the ED 12-50mm side-by-side the company’s own FourThirds-based ED 12-60mm f2.8-4.0 would answer a number of questions for anyone looking at considering adding it to their collection. This is certainly one lens that goes far beyond its on-paper ‘disappointing’ optical rating.

When Olympus shocked the world with the new E-M5 on February 8 2012, it did so by announcing the impending arrival of two further lenses even while it often appeared in all the launches throughout the world with the ED 12-50mm mounted. And like its recent fast primes, here were two that would push the Micro FourThirds reputation beyond anything detractors might have in mind.

Now that the E-M5 was able to silence many of Olympus’ critics, the anticipation of the new ED 60mm f2.8 Macro and the ED 75mm f1.8 was simply icing on the cake. As we look back in hindsight, these two lenses would prove further sticking points for the company’s competitors and the evidence was there in droves as countless existing users and owners of APS-C DSLR outfits were by now quickly changing over to Micro FourThirds with the E-M5 being one of the leading reasons for the migration.

The arrival of the E-M5 was without a doubt very important in view of the direction that Olympus has now decided to travel on. This was especially true considering the recent release of truly outstanding high-performance glass and the 60mm f2.8 Macro and 75mm f1.8 were no exception. With the E-M5 signalling that Olympus has undoubtedly finally ‘arrived,’ many were able to simply focus on these and the other lenses unreservedly and without entertaining doubts over the actual capabilities of Micro FourThirds. Indeed there was a time not so long ago that the same people were talking about the maligned noise performance at higher ISO settings or its autofocusing ineptness. With the E-M5 and its Sony-sourced sensor, most of these issues are now history – users were truly enjoying the outstanding lenses in a purely unfettered fashion. Truly these two new lenses couldn’t have arrived at a better time.

M.Zuiko Digital ED 60mm f2.8 Macro (black version only) Image courtesy of Olympus Imaging Corporation

The ED 60mm f2.8 Macro had a tall order to meet. For Olympus, the goal was to either match or surpass the macro king of the industry, its very own FourThirds-based 50mm Macro f2.0. And in the new 60mm Macro with its Z.E.R.O. coating, that challenge was met handsomely, producing outstanding performance at life-size (not half life-size as is the case with the 50mm Macro) magnification at 0.19 metre minimum subject distance.

Furthermore, like the 12-50mm, the 60mm Macro is weatherproof. Manual focusing was easy, very well weighted and works like a charm. It might not have Snap-Focus but it looks like it doesn’t need it. Unlike the 50mm Macro, autofocusing performance is fast, assertive and very positive despite the typically extended helicoid length. At a film equivalent of 120mm, it serves handsomely as a telephoto lens with excellent defocusing at wide open aperture. It certainly isn’t as visceral an experience as the 45mm f1.8 when it comes to non-macro use – for that, the second lens introduced is more than a match. Enter Olympus’ highly vaunted ED 75mm f1.8 in the true tradition of its mighty film-era Zuiko 150mm f2.0 lens.

M.Zuiko Digital ED 75mm f1.8 in black and chrome versions Images courtesy of Olympus Imaging Corporation

At that focal length, the ED 75mm f1.8 is versatile. It’s entirely usable in virtually any situation where a 150mm focal length is ideal. That means indoors and outdoors, in short-range sports, theatres, concerts and studio portraitures. It’s great for any corporate events including also weddings. Like the 12mm f2.0, this is a formidable lens, utilising 3 ED and 2 HR lenses among its 10 elements arranged in 9 groups. Its MSC mechanism produces whisper-quiet focusing and with the help of a nine-blade diaphragm and a wide open f1.8 aperture setting, bokeh is super soft and buttery smooth.

By this point it looks like all ‘premium class’ (we and not Olympus use this term for easier reference) prime lenses use Z.E.R.O. coating, which is to be expected. With the 60mm Macro and 75mm arriving, the ‘M’ lens range has suddenly grown very impressively. Even while there are still gaps to fill, the range has fleshed out quite outstandingly. Here are the fast newcomers rocking the market – 12mm, 45mm, 60mm and 75mm. That’s an equivalent coverage of super-wide 24mm to 150mm medium telephoto. In between we have primarily short tele lenses on offer. What are obviously needed are some medium-wide and standard focal length offerings to further broaden the appeal.

Within half a year, Olympus unveiled an equally fast 17mm. At f1.8 nothing is faster on offer from Olympus but it’s wetted enough appetites among the brand’s mirrorless fans and followers for faster variants to come. To be fair their demand isn’t really outlandish – during the film days, f1.8 lenses of this focal length or thereabouts, aren’t considered ‘pro’. For example the Zuiko Auto-S 50mm f1.8 was essentially meant for ordinary users. For more serious performance expectations, Olympus had on offer at that time two others, namely the 50mm f1.4 and also the 50mm f1.2, the latter of which replaced the earlier 55mm f1.2.

M.Zuiko Digital 17mm f1.8 shown in chrome version with the optional hood attached (left) and unattached in black (right) Images courtesy of Olympus Imaging Corporation

At any rate, for now at least, the new 17mm f1.8 was basically ‘what the doctor ordered’ – a very handy standard-wide lens that is sufficiently bright for pretty much most of the situations one can think of. Even by Olympus’ ‘M’ lens standards, it’s not overly heavy (at 120 grams) but when compared to its ‘simpler’ sibling – the 17mm f2.8 – it’s almost twice the weight (120 versus 71) and 14 millimetres longer (36 versus 22). The brighter version neither focuses down to as near (0.25 vs 0.2 metre) nor gets up to as good a magnification factor (0.08X vs 0.11X). However it’s obvious that its optical performance and build quality are on a different plane. Unlike the cheaper version, the 17mm f1.8 has metal construction and offers Snap-Focus like the 12mm lens. Interestingly while the earlier fast bunch (12mm, 45mm, 60mm Macro and 75mm) all received luminous and often rave reports, the 17mmf1.8 was surprisingly mute. That’s not to say there weren’t any favourable impressions (as they are many) – somehow they weren’t as emotionally charged. In all fairness, the 17mm f1.8 was probably a victim of Olympus’ renowned optical capabilities. If its illustrious peers in the range did not exist, impressions might have been a whole lot different. As it stood, it was probably overshadowed but not overly shaded. Most people would still use the 17mm f1.8 and remain very impressed by it.

The introduction of Olympus’ fourth-generation Pen models (E-PL5 and E-PM2) on September 17 2012 proved more than surprising. For one, the E-P3’s successor was missing. For another, a new lens – the 15mm f8.0 – certainly proved bewildering. Just as everyone was expecting the next big thing (another fast lens, in other words), this unusual piece of glass merely confounded everyone. However Olympus offered their brand of logic during its introduction.

Olympus Body Cap Lens (BCL-1580) rated at 15mm f8 shown in white and black varieties (red and chrome also available) Images courtesy of Olympus Imaging Corporation

The 15mm f8.0 is what the company calls a ‘body cap lens’ and by that, they suggest that in place of the conventional body cap to cover the camera lens mount, this could well be a better solution. Such situations come into play when you may have the camera in your bag or in your trench coat pocket while you’re walking. When the opportunity arises to quickly grab the odd but interesting shot, you often find yourself struggling to get your act together. You lose crucial time thinking of what lens to attach let alone mount it on, turn on the power, aim and press the shutter button. Even so the camera has to autofocus, lock on to your subject and then make the exposure. The time taken to complete that whole process is likely to mean you’ll miss your opportunity because your reaction will always be to catch up with the idea of taking the shot. Meanwhile your camera will also have to respond and the response time can be slowed down by the fact that the autofocusing has to play its part.

In developing the design of the 15mm f8.0, engineers at Olympus took all of these into account and equip it with five important attributes.

Firstly the film equivalent 30mm focal length was chosen because it offers a very pleasant standard-wide field of view that happens to have minimal linear distortion and by nature, a favourable depth of view. At that focal length, the lens could also be kept very thin and by using a unique optical arrangement, minus the necessary focusing mechanisms, Olympus could make it resemble as close as possible, an actual body cap. At the very least it might now be possible to fit that combination in a jacket pocket.

Secondly there are no aperture settings to select from; nothing bigger or smaller than f8.0. In other words the diaphragm will move to f8 and no other position. Without the necessary mechanics involved, the 15mm lens can be made very simple. Olympus chose f8 and no other f number because most lenses perform best (in terms of resolution) when set to this aperture. At the same time f8 produces the best depth of field performance, ensuring that there is field focus across a large enough area in the front and rear of the subject. This translates into a very usable level of sharpness from 0.3 metre and beyond.

Thirdly the 15mm lens lacks autofocusing, which is why whichever camera you mount that lens on, you don’t need to account for the time to lock focus on the subject. You can very well press the shutter button and expect the exposure straightaway. The response is just about instantaneous.

Fourthly it also doesn’t have manual focusing. No auto and no manual focusing suggests that the 15mm lens is devoid of any movable optical elements inside. At the same time, it is obvious that the element that would have been used for focusing is fixed to an infinity distance setting to optimise image sharpness.

Lastly without all the necessary mechanical components for a controllable diaphragm and autofocusing, the whole lens could be made not only simpler but because all of these free up large spaces, it is also lighter and smaller. The lightness is extraordinary – the 15mm is only 22 grams in weight. Compared to the next lightest lens in Olympus’ line-up, that’s a whopping 49 grams less! In terms of size, the 17mm pancake lens, at 22 millimetres, is almost two-and-a-half times longer. Measuring 9 millimetres – or about one-third of an inch – it’s really not much thicker than a simple plastic body cap.

Given its quirkiness, it’s highly unlikely that there will be other ‘body cap lenses’ to join the system. Having said that, we believe there is some degree of usefulness for a lens that has the potential to turn any Pen camera in a very high-quality Box Brownie that even in the hands of the most notorious tyro, will still produce technically proficient images. If you ever need to let your granny use your Pen for the next few hours, this might just be the lens that would save her the blushes. Given how inexpensive it is, there might still be uses for the 15mm f8.0 that the world has yet to discover but take your time – it is doubtful it will ever have any serious competitors waiting to challenge it.

In almost every way, this reissued version of the ED 75-300mm released almost three years earlier (August 31 2010) is internally identical. The optical configuration and design hasn’t changed. The same three ED elements are there and so are the Super ED element and the HR lens. All of them continue to suppress chromatic aberrations. However for the series-II version, Olympus updated it by applying their Z.E.R.O. coating technology to make the update a marginally better optical performer especially when it comes to dealing with ghosting and flare.

The updated M.Zuiko Digital ED 75-300mm f4.8-6.7 still available in only black Image courtesy of Olympus Imaging Corporation

Externally the ED 75-300mm II has also by upgraded, inheriting the company’s new design language that helps to keep it abreast of the newer generation of Pen cameras including the new E-M5. Despite the adoption of the advanced coating, there have been some minor differences in its physical attributes. For example the new version is ever so slightly narrower (by 1mm) but a smidgen longer (by 0.5mm). While filter size remains unchanged at 58mm, it is, at 423 grams, however 7 grams lighter, which is rather quite a bit surprising. We’re not sure where this weight saving comes from (certainly not from the coating) but we have a sneaky feeling that at least one (if not two) of the 18 available optical elements may have been plasticised.

go to next instalment a history of Micro Four Thirds part VIII - timeline of cameras and lenses