The best 50mm for A7RII

After testing the Sony Carl Zeiss 55mm f/1.8 FE in 2014, I was less than impressed. I may have had a decentred example (it happened to dPreview and at least one photographer I trust to know his lens performance expectations). It was, certainly, pin-sharp on a test chart or a brick wall but the moment three-dimensional subjects were involved at wide aperture the defocused detail could be very untidy. The clip below from trees behind a building which was sharply focused is at f/1.8 and 1/2500th (a suggestion that it could be caused by camera shake is easily ruled out). See my additional notes at the end!

cz55mm1p8distance

It’s worth saying that when I had this lens I made some tests of the bokeh using very strong defocus which looked good. Many examples I’ve seen, which true believers put forward, show a figure (from full length to portrait) centre of a horizontal frame at f/1.8 with a pleasant enough looking distant background. My gripe has been with what happens when your subject is further away, or the background is not all very distant. This is an expensive lens but it seems to me to have fussy bokeh with too much CA fringe and also more focus-related colour shift than desirable.

Here is a full size example with EXIF. Honestly, the best standard lens around? //www.pbase.com/davidkilpatrick/image/162847304

Now I’ve got a fair collection of 50, 55 and 58mm lenses and also the little Canon 40mm f/2.8 STM which is my alternative to having a 35mm and a 55mm. No matter what the lens – Pentax, Minolta, Sony 50mm f/1.4, Helios, Zenitar, Nikon, CZ Jena – the full aperture between f/2 and f/1.4 always proves to be a touch soft. They all have residual aberrations that the CZ 55mm f/1.8 design has eliminated. While they can have a smoother bokeh, they also have marked colour shifts and uncorrected CA. Generally, they also all perform extremely well once stopped down to f/8 and most designs are great by f/4.

Despite the advantage of full AF functions, the CZ 55mm does not have a particularly good close focus or maximum image scale. In use I often found myself framing up closer than 50cm. That’s half a metre – it’s even further than the old 55 and 58mm lenses of the 1960s, which generally manage 45cm. I find this limitation hard to understand. 50 years ago CZ Jena started to put helicoids on their standard 50mm lenses which enabled focus down to 35cm. We have gone backwards since then.

And then I realised I’ve already got a lens which is free from all vices, gives me AF and manual focus options using adaptors I already own, which cost me about a third of the price of a CZ 55mm – and I was not being used on my A7RII. We bought a good used example of the Sony SAL 50mm f/2.8 Macro to use with our Alpha DSLR.

First of all, I compared this with the idea of buying a Zeiss Loxia 50mm f/2, by fitting it to the LA-EA3. Although the focusing ring does not communicate to the camera to invoke magnified manual focus, the lens has a Focus Hold button which can be set to this. The focusing throw is steep but in practice very accurate focus is easily set. At f/2.8, the lens is already perfectly sharp with some contrast improvement at f/4. The lack of vignetting and distortion, the flatness of field and generally very attractive smooth defocusing without CA issues make the lens better than typical fast standard designs.

On the LA-EA4 with autofocus, a limited set of AF functions ends up activated and there’s always the issue of the slight delay and sound caused by mechanical aperture operation. AF-C is of limited use, along with this video functions. However, I don’t generally use this type of lens for action or for video.

I made plenty of non-image tests by defocusing bright edges, both ways, and could find no hint of colour problems. I then set up a small food shot using the close focus – exactly the reason I find a lack of close focus restricting – and made tests at f/2.8, f/5.6, f/11 and f/22 to look at the bokeh. My conclusion is that I will be hard pressed to find anything technically better, or with a more pleasant character to the background defocus, in the c.50mm focal length. The series covers all four apertures.

I am aware that one comment will be that f/2.8 simply isn’t wide enough. There’s no significant differential focus and you’d need 50mm f/1.0 to get what many photographers want. However, this is all to do with viewing size. We all tend to see pictures on smartphone screens, on Facebook, or even on our own camera three-inch screens. In fact, at f/2.8 there isn’t enough depth of field for a typical real-world use of a full page reproduction and f/5.6 is just about right. For a poster, f/11 would be good. At f/22 the whole image is slightly softened as expected and it’s just there to complete the set.

For the moment – at least until a Batis version of the 50mm f/2 Makro Planar appears and answers all my demands perfectly – I think this Minolta-derived 50mm macro will do fine as my ‘standard’ lens.

David Kilpatrick, aka ‘some random blogger’ (©SAR comments March 2016)

Added August 30th 2016: Sony has announced an E-mount 50mm f/2.8 Macro focusing to 1:1 with a stated RRP of $500 – really, they must have read this article in March. In the meantime, during the Brexit fiasco I caved in and bought a 55mm f/1.8 CZ, suspecting the price would be 20% higher soon enough (and sure, it was). My new example is no better than those I originally tested but it has its uses and in a flat plane – no defocused image to screw the results up with an ugly mess – it’s the sharpest 50-55mm I have used. I’m still using the 50mm macro and recently spend a month using the Samyang 50mm f/1.4, which is not as sharp as the CZ but handles blur and bokeh more elegantly. Both lenses don’t really excel at suppressing Longitudinal CA, one of the strengths of the A-mount macro. Hopefully the new SEL FE 50mm macro will also give clean, colour-shift free foreground and background bokeh.

Added July 29th 2017: I have now bought the 50mm f/2.8 Sony FE Macro, and put my A-mount macro lenses up for sale. The E-mount focuses to 1:1 rather closer than I would like, at 16cm which indicates its internal focusing changes the focal length to something more like 37mm to 1:1 (16cm is a pure 40mm at 1:1 assuming no optical thickness to the lens). It’s an extremely sharp lens with bokeh as good as the A-mount 50mm and no trace of CA.

Sony’s precision aspherics

In interviews about the new micron-accurate aspheric lens element moulding process used to increase the resolution of the latest Sony G Master lenses, a visual has appeared which shows the ‘onion ring’ effect that coarser mould machining causes in lens elements.

Working independently, I’ve been aware of this for years – and I have used a point-source photography technique to study lenses. I’m not an optical engineer or scientist, indeed I don’t even have a degree in anything. I came into photography through Victorian books and teenage years experimenting with lenses, developer formulae, building my own equipment and using observation, corollary and deduction to understand how things work. It’s helped me explain difficult technical stuff to many thousands of readers through books and magazines, without using maths or formulae, and very few diagrams.

In the quarterly magazine Cameracraft which ran for three years from 2012 to 2015, edited in conjunction with Gary Friedman who does have all the right qualifications but is also a dedicated empiricist and experimenter, I published a home-brewed rendering of aspheric moulding visual analysis.

Here’s Sony’s visual showing the difference between traditional aspheric moulding (pressed glass aspheric, as pioneered by Leica and Sigma) and their new refined pressing with better engineering.

onion

And here is my home-brewed visual from Cameracraft when I explained the bokeh and resolution issues created by pressed elements (and also, some other aspects of bokeh, which I’ll refer to below the image):

onion-ours

This is a clip from a 2013 article in Cameracraft dealing with broader aspects of bokeh, depth of field, aberrations and how images are rendered. You can download the two-page article here. We’re sad that Cameracraft eventually ran out of funds, but it is now part of f2 magazine – heavier and more expensive, and not so ‘dedicated’ to the peculiarities and technicalities of our craft. If I can find a way round the title registration and distribution agreements, one day f2 Cameracraft will become just Cameracraft. It was a great title back in Ansel Adams’s day and it’s a great title still!

Here is the full article as a downloadable PDF.

As far as I can tell, Sony’s new superlens is not going to be any better than the Sigma 70mm f/2.8 macro which I still use. My reasons for choosing this macro are simple – it is optically excellent and traditionally made without any aspheric or other special elements, and it uses simple focal extension for focusing, not rear or internal group movement. This means it’s a true 70mm lens even when used at 1:1 and gives the maximum lens to subject distance, for its focal length.

However, it’s going to be MUCH better than the Voigtländer 50mm f/1.4 used for the colour bokeh shift example at the top. Sony’s information makes it clear that the new more precise aspheric moulding allows new surface profiles and the elimination of chromatic aberrations which cause this magenta-green foreground to background shift in so many otherwise excellent lenses. I’ve said that to do so, the new lenses must be what would once have been called Apochromatic, though that term has only ever meant that all wavelengths focused to the same plane and at the same scale. Even past Apo lenses can show poor colour bokeh. It’s interesting that Sigma, after years of plugging the APO (capitals not actually needed, folks!) label chose not to label some new lenses this way even through their performance matched or exceeded earlier APO models. Sony seems to be taking the same view – G Master will be sufficient label to imply very high resolution, elimination of bad colour bokeh shifts, and by implication an apochromatic performance on RGB sensors.

So will I be buying these amazingly expensive, large, E-mount dedicated lenses? Probably not. My unscientific observations tell me there are smaller, lighter, far less expensive lenses which will serve me better. Mirrorless digital camera bodies with high quality EVF and high magnification focusing allow me to  do things I could never have done over 40 years ago when I took my first position as a Technical Editor (of the UK monthly Photography published by Fountain Press and edited by John Sanders). Geoffrey Crawley, editor of the British Journal of Photography, showed me how to evaluate any lens quickly with the help of a light bulb, a darkened studio, a roll of background paper and a sharp pencil. Back then you had to expose film, now you can just look through the finder. In a photo store, any LED spotlight will do for a quick check. Focus centre, magnified to max, at full aperture. Move to all corners in turn without refocusing, magnify each time. Refocus each corner in turn when magnified, examine change in rendering of point source. Buy the lens which shows symmetrical, balanced results and the best sharpness of the corners when the centre is correctly focused. Do this with a light source at least 3m/10ft away and if you can, even further. Repeat one stop down, two stops down, with zooms repeat at three or four focal lengths across the range. Never do it at close distance (hint: lens test chart results are only good for the distance you photograph the chart from, which is why Imatest, DxO and other labs have test targets the size of a wall and industrial sized space to work in).

And, if you have a single LED bulb or miniature LED torch, you can examine any of your lenses in a darkened room and produce a ‘bump map’ which will reveal its moulding defects, scratches or fungus, blemishes, and population of dust and microfauna.

– David Kilpatrick

dk-cameracraft-bokeh

To subscribe to the continued incarnation of Cameracraft, f2 Freelance Photographer incorporating Cameracraft, just visit http://www.iconpublications.com

For our PDF and App editions, go to Pocketmags where you’ll find Apple iOS, Android and all the usual choices to subscribe or buy individual editions. The next issue (below) will be delivered on February 10th.

f2marapr2016cover-web

And if you really want a trip back in time – there were huge changes between 2012 and 2015. Cameracraft documents the rise of mirrorless, the growth of hipster retro, and the discovery of older manual lenses as it happened. You can read a full set of the 12 issues via this one-off YUDU subscription:

Click to view the full digital publication online
Read Cameracraft 2012-15
Self Publishing with YUDU

NEX-7 close cousin reaches astronomical value

A crowd at a charity auction in Florida couldn’t believe their eyes as two brand new Hasselblad Lunar cameras with a joint retail value of around $14,000 suddenly rocketed in value to $54,500 (from Hasselblad press release this afternoon).

Two photo enthusiasts at the world-famous three day-long annual Amelia Island Concours d’Elegance exotic car festival began bidding against each other for the chance to own an ‘ultimate luxury’ olive wood-handled Lunar camera, crafted by the iconic camera brand.

Lunar Olive Wood 18-55 Hood_b

When the bid reached $28,000 neither party wanted to lose out on a Lunar, so a deal was struck for an extra camera to be auctioned – for a joint record-busting price that raised a total of $54,500 for a spina bifida charity.

The deal also included a unique set of classic motorsport photographs shot over decades with a Hasselblad camera by Concours Show founder and chairman, Bill Warner.

Warner said: “Hasselblad is simply the ultimate camera. It’s the Mercedes-Benz, the Porsche and the Ferrari of cameras, all in one.”

The Amelia Island classic car and automotive art festival, which is billed as ‘three days of automotive passion at the International Historic Motoring Awards, Motoring Event of the year (2013)’, draws classic car enthusiasts from across the globe each year and raises millions of dollars for charity.

Michael Hejtmanek, President of Hasselblad Bron Inc. said: “We knew our new, retro-look Lunar range was compelling – especially the rich-veined olive wood edition with its advanced technology and supreme ergonomics – but for a pair of them to raise $54,500 for Spina Bifida Jacksonville at this auction is just outstanding.”

Further information:

http://www.hasselblad-lunar.com/
http://www.spinabifidajax.org/
https://www.ameliaconcours.org/

Our comment: fortunately, charity auctions are always about the charity not about the real value of the items. These are still only worth a little compared to the actual lunar-landing Hasselblads, of which four are thought to be surviving in the wild and surfacing at auctions from time to time.

Using the 10-18mm OSS zoom on full frame

The Sony E-mount (not FE) 10-18mm f/5 OSS lens can be used effectively on full frame for creative work and within limits for technically more demanding shots. Below, an uncropped A7R shot of the concourse at Abu Dhabi Airport, taken at 13mm setting, f/6.3 with my lens profile as provided below. Check the straight lines in the floor tiling, if you doubt that this lens would be of any use for architecture.

However, you don’t get this without a lens profile, and without due care to limit the focal length to a range of 13 to 16mm – not the full 10 to 18mm. Below, you could get this if you try 12mm straight out of camera…

uncorrected12mm

This is a pretty awful case of vignetting and distortion – as you would expect. It’s from an APS-C format wide angle zoom, the 10-18mm f/4 SEL OSS lens for NEX, used on the Alpha 7R full frame mirrorless body. Early in the launch period of this camera, various far more attractive images appeared on-line using subjects like roads, rail lines, beaches and even shop counters where the lines look straight – rather like that drainpipe – because of where they fall in the shot. As you can see, anything with a horizon near the long edge of the framewould have given a very different impression.

However, Adobe offers a free utility which enables you to make lens profiles to correct vignetting and distortion.

I created a lens profile for ACR/LR using full frame and the 10-18mm on the A7R. The vignetting is such that the profile creator really can’t handle it, and overcorrects the extreme corners as a result. I’ve done f/4, f/8, f/16 at 12, 14, 16 and 18mm focal lengths using an A2 chart; for a lens like this, a much greater working distance and an A0 chart would really be desirable. The link below is to a zip file of the Adobe Lens Profiles I produced – for A7 and A7R, with .lcpp files for final use, and .lcp files for different settings of the 10 18mm I found useful.

10-18AdobeLensProfiles

corrected-customprofile12mm

At 12mm you can probably see the vignetting artefacts in the corners, the magenta corner shift and incomplete correction of the horizon line. You’ll also be quick to spot that the 12mm coverage has been reduced to something much less, lens profiles always reduce the field of view (they can not do otherwise).

The profiler simply can’t handle the degree of sudden fall-off in illumination given by the 10-18mm used on full frame. Manual distortion corrections can actually do a better job. At other focal lengths, the profile I’ve made works well enough, and if the frame is cropped slightly (still exceeding the APS-C area the lens is designed for) it’s possible to get good results and wider angles.

I have sold my Sigma 12-24mm HSM II which was used with the A99, and also sold a Voigltander 15mm f/4.5 I bought to test (zero cost fortunately, as it made a small profit between Gumtree source and eBay destination). The Sigma was not only very difficult to focus using CD, its HSM motor won’t play with Sony CD.

My .lcp full-frame file can be downloaded from:

//www.photoclubalpha.com/AdobeCameraProfiles/ILCE-7R FF (E 10-18mm F4 OSS) – RAW.lcp.zip

Just for good measure, here is an uncropped A7R 13mm focal length shot of the church of Maila Dumpara in Kerala taken to use dramatic converging verticals – which fail terribly unless the lines are properly corrected, the last thing you want in a strong upward angle is lens distortion. It’s very stiff test of any lens to do this. I have left the vignetting uncorrected. I rather like it. Click either this or the Abu Dhabi photo and you’ll get a larger image, about 1000 x 1500 pixels.

Samples produced for a dPreview forum question

There’s been a lot of discussion on dPreview forums of which lenses work on full frame E-mount, as Sony saw fit to put a Disable APS-C crop option in the menus of the A7 and A7R (almost as if they wanted owners to experiment). They have made other welcome changes of a similar kind which I’ll cover in a full review of the camera – which I can not do yet as I have no FE mount lenses for it, and with the current choice and prices, I can see I may never use FE mount lenses on this camera.

So, to answer some questions on dPreview’s E-mount forum, I posted these images and comments.

Here is a ‘native’ uncorrected shot of a local building taken on the 10-14mm on A7R at 11mm, f/10, ISO 100:

View: original size

Here is the result of using the profile, doing a crop and some straighten of slight rotated tilt, and pulling the scale down (with the profile applied, the roof apex is clipped off at the top as the lens has so much distortion its 11mm probably becomes more like 15mm when corrected):

View: original size

I’ve used some clarity and local burn adjustments on the sky to treat the image more or less as I would (except that I wouldn’t actually photograph this building at this time of day, with blinds drawn, etc).

For me, the 10-18mm on A7R with our without the profile correction offers the same options as using assorted lenses on 5 x 4 sheet film. It never mattered whether a 47mm didn’t cover the entire film, you got an image circle and could use whatever part of it you want. At 10mm the image, with the profile used, has strong corner cut-off but the overall circle of usable image greatly exceeds APS-C provided you stop down (f7.1 seems just OK, f/10 is maybe optimum, I’d certainly try f/16 despite fears of detail loss).

View: original size

The red crop mark is square – my ‘Hasselblad SWC killer’, as the classic SWC had just a 38mm wide angle lens. You needed to get an Arcbody with 35mm Rodenstock to go any wider on 56 x 56mm film (6 x 6). With the A7R and 10-18mm at 10mm, you get the equivalent of a 24mm lens. Not a 24mm fisheye on 6 x 4.5 like the widest ever offered by Mamiya… a 24mm rectilinear on 6 x 6.

The yellow crop mark represents a significantly larger area than APS-C (which is actually just a little under the 24 x 24mm square in width). It is shifted vertically, as if the lens was being used as a shift lens. If only the APS-C area is considered, its approximately 16 x 24mm area can be positioned right to the top of the frame, equalling a 4mm rise, or the equivalent of using a 6mm rise on a full-frame PC lens (most actually go to 11 or 12mm rise). There is only one lens made which can compete with this, and that’s the Canon 17mm f/4 TS. Admittedly this is a superb lens and when stopped down to f/11 and used on the 6D (Canon’s most shift-friendly sensor) will blow this result away for clean rendering of detail toward the frame edges.

And then, you can still use the 10-18mm in APS-C crop mode as a snapshot wide angle with pretty much perfect correction (Adobe’s own Sony profile for APS-C), for videos too.

– David Kilpatrick

Nikon's D600 – FX goes Prosumer

D600 with 24-85

Nikon announced the D600 at 5am today, confirming rumours which were beaten only by Apple’s iPhone 5 leaks for accuracy.

The 24Mp entrant seems to be part of ‘full-frame fever’ undoubtedly driven by Sony’s CMOS sensor development, pricing and more crucially, packaging the definitive 35mm format to appeal to mainstream consumers.

Despite a D3X matching resolution, the D600 is a very different sensor and package. Will this be the camera to push Nikon’s DSLR market share to over 50%?

The current DLSR line up at Nikon is quite striking, not only for capability but also the positioning, with a substantial gap between the highly-specified DX-crop D7000 and the 36Mp professional D800 bodies. The middle ground retains the D300s, almost identical in price to the D7000 but qualifying for Nikon Pro User status and now one of Nikon’s oldest DSLR bodies. The D600 fits at the upper end of that gap, with an SRP of £1955.99 in the UK for the body.

For that price, you get a tightly controlled feature set, a compact, lightweight body and sensor capabilities that exceed the state of the art just 2 years ago, when the D3X was in demand, in short supply, and retailing at over twice the D600’s figure. A quick launch-venue play suggests that the specified ISO range – peaking at 6400, rather than the D3X’s 1600 – is very usable. The body weighs only 760g, using a magnesium upper and rear body and offering similar weathersealing to the D800.

Advances in processing, video and OS make themselves felt instantly. FX and DX crop HD video recording with HDMI output for uncompressed streams and sophisticated audio monitoring, a base ISO range from 100 to 6400 extendable to 50 to 25,600, and in-body raw editing are all very compelling features regardless of resolution. The D600 manages 5.5-6fps in full-frame mode, and shoots to two UHS-1 SDHC cards.

The 100% viewfinder is bright and despite using the square, without blanking filter, window rather than the round type used on previous FX bodies seems very similar to the D800. The eyepoint may be a further slight reduction, but without detailed specifications that’s a hard one to call.

A true pentaprism is used – expected, perhaps, in a full-frame high-end body but fighting an increasing trend for electronic viewfinders.

A compact body presents a few ergonomic challenges, and Nikon have tackled the control interface with the experience you’d hope for after the clear new direction shown in the D4. Gentle slopes define the shutter release area, with joystick, function buttons and the standard buttons beside the 3.2″ screen (which features a clip-on protector). A mode wheel/drive wheel combination provides consumer-style selection of scene modes, with a drive wheel below including selection of the IR remote mode, which is supported by receivers on both the front and rear of the body as per the D7000.


Nevertheless the D600 is a consumer package. It’s a high-end one, but it carries a 1/4000th shutter, horizontal axis level only, consumer interface sockets (the compact remote/GPS port rather than the screw-in port of the pro bodies, and no PC-sync socket). Unlike the D800, the D600 has USB 2. At launch, it seemed that the WT4 wireless tethering solution was not supported, but some of the launch material suggests that it is supported, alongside the low cost WU-1b introduced specifically fort he D600.

The Android remote control application for the WU-1b (below) is already available; an iOS version will follow before the end of September 2012. It offers rather less control than Camera Control Pro, but does provide a live-view relay and release function.

That WU designation has been seen before, on the similar accessory for the determinedly consumer (and best-selling) D3200. It’s a wireless broadcast unit slightly more sophisticated than using an Eye-Fi card, and at £64 is almost a tenth of the SRP of the WT4. It sacrifices many of the camera control functions (though triggering is possible), and is mainly intended to transmit and share images via Android or iOS devices. It’s a shame that this split exists in Nikon’s line, as the WT4’s full-fat networking and storage solution is a lot for many studio photographers who would probably find the basic transfer/triggering of the WU-style units very useful on the pro bodies.