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Sony A7II full frame with Canon EF 50mm f/1.8ii vs Olympus OM-D with PanaLeica D 25mm f/1.4 lens – real world comparison images

Monday, May 1st, 2017

These two lenses give a similar field of view – that of the “Standard lens” or 50mm in full frame terms.

I have posted similar DOF and background blurring comparisons for full frame 85mm f/1.8 vs Olympus 45mm f/1.8 and also full frame 85mm f/1.8 vs Olympus 75mm f/1.8 taken twice as far away.

This blog post is to demonstrate the slightly shallower depth of field (DOF) and more background blurring that a full frame camera can attain over a Micro Four Thirds camera – but does it make the image more aesthetic, and is the difference really worth losing all the fantastic benefits of Micro Four Thirds – smaller, lighter, less expensive kit, easier to take traveling, to social events and hiking, better weathersealing, better image stabilisation, touch screen AF, closest eye AF, more fun and versatility, and the list goes on.

Only you can decide if you really need to go shallower DOF – and of course on both cameras you can get even more shallow DOF – the full frame allows use of 50mm f/1.4 lenses (and even a Canon EF 50mm f/1.2L), while on the Olympus OM-D, you can use the wonderful superb Olympus micro ZD 25mm f/1.2 lens, and if you want, you can go to f/0.95 lenses but currently only in manual focus.

The Canon EF 50mm f/1.8 II lens is known as the plastic fantastic – perhaps one of the worst build quality of any modern AF lens, and a cheap price to match but it has reasonable optics – although, not the sharpest tool in the shed wide open, and has lots of vignetting on the Sony a7II, plus lots of coma aberration and the bokeh is quite busy and often annoying – but this comparison is just to show DOF and degree of background blurring at f/1.8. When used with the Sigma MC-11 EF-Sony lens adapter, you do get fairly fast AF but no Eye AF, BUT it is very frustrating to use as you must re-mount the lens every time the camera is turned off or goes to sleep, and sometimes AF is a very slow stuttering experience. For some reason, the Sony a7II under-exposes this lens at f/1.8 but not at f/2.8 – very strange indeed!

On a full frame camera such as the Sony A7II mirrorless camera, the Canon EF 50mm f/1.8 ii provides the user with a further 1.3 stops of shallow depth of field options when compared to an Olympus OM-D E-M1 II with the old, now discontinued, Panasonic leica D 25mm f/1.4 Four Thirds lens but will this really matter for most people and will the many benefits of the Olympus system outweigh the DOF benefits of the full frame system?

Note that this Four Thirds lens is one of the few that is compatible with CDAF, but for some reasons, AF is stutteringly slow on the Olympus OM-D E-M1 mark I but works fine on the mark II camera. This lens was replaced with a smaller, lighter, less expensive Micro Four Thirds version. Neither are weathersealed but the new Olympus mZD 25mm f/1.2 lens is.

Real world lens tests:

Let’s have a look at some jpg images straight from camera (just resized for web viewing) with both lenses wide open as I walked around some gardens yesterday, not really looking for great shots, but shots to show difference in depth of field and image quality between the two systems when taken from the same camera position.

The Panasonic 25mm f/1.4 lens is first then the Canon 50mm f/1.8 lens, both taken from same camera position:

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Note that the severe mechanical vignetting of the Canon EF 50mm f/1.8 II lens on the Sony a7 II is causing much more annoying “cat’s eye” shaped bokeh near the edges – note the sky highlights, as well as much darker corners. In addition, the longer aspect ratio of the full frame system makes it harder to exclude distracting skies in portrait orientation than it is with the wider Micro Four Thirds 4:3 aspect ratio – another reason I prefer Micro Four Thirds for portraiture.

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The greater blurring capability of the full frame is well demonstrated here but the near out of focus leaves on the right are far more annoying with their distracting bokeh compared to the less blurred but less distracting bokeh of the Panasonic image.

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When the focus point is farther away, the difference of the degree of background blurring becomes less between the lenses – as demonstrated with my previous posts.

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For this image, the 25mm lens gives adequate subject isolation and background blurring, and I think it has much nicer bokeh, plus if you look at the highlight area of the statues’ head, the cheap and nasty 50mm lens has much more flare, softer, less contrasty imagery – that’s one of the resons why you may want to pay more for a higher quality lens!

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Again the 25mm gives adequate background blurring and it is less busy – look at the branches of the birch – but this bokeh issue is not a full frame versus MFT issue but a lens design issue.

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The larger out of focus circles of the 50mm are actually much more distracting and annoying – sometimes the more background blurring is actually worse for aesthetics!

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Again the 25mm gives adequate background blurring and it is much less busy with nicer bokeh.

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This closer image of grapes, looks nicer with the 50mm lens to my eye as the much larger out of focus bubbles make it less busy.

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The 50mm lens here is giving too much background blurring making it hard to work out what is in the background which can work against the aesthetics by making the viewer work too hard – of course, the 50mm could have been closed down to f/2.8 to address this.

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The bridge looks busier on the 50mm lens – the 25mm to my eye is giving nicer bokeh and sufficient background blurring.

Moral of the story:

Just buying into a full frame system does not guarantee you nicer looking, shallower depth of field, more aesthetic bokeh – you do need to choose your lens carefully, and lens design is always a trade off between wide open sharpness vs wide open bokeh:

The superbly sharp, big, heavy, expensive, Sigma 50mm f/1.4 Art lens has busy, distracting bokeh – sort of defeats the purpose of having a shallow DOF lens.

The Canon EF 50mm f/1.2L lens has buttery smooth bokeh but is soft (not that sharp) wide open with lots of aberrations.

The Canon EF 50mm f/1.4 lens is soft wide open with lots of aberrations and often busy bokeh but at least it is relatively small and inexpensive.

The Sony FE CZ 55mm f/1.8 ZA is sharp across the frame, relatively compact but has busy onion ring bokeh and costs $AU1150.

The Sony FE 50mm f/1.4 ZA has nice bokeh and is sharp in the centre wide open but is soft half way to edges and will set you back $AU2250!

See also my comparison table of the high end 50mm AF lenses for a Sony full frame.

And here we have the full frame conundrum – which is the lens that suits your needs best and can you afford the cost and weight?

If you are going to have stop it down to f/1.8 or more for adequate image quality or depth of field, then perhaps you are not really gaining much over an Olympus 25mm f/1.2  lens which is weathersealed, compact, relatively light, has almost zero aberrations and minimal distortion, probably better edge-to-edge sharpness wide open, can focus twice as close, has a lovely manual focus clutch, and has by far the best image stabilisation of 5EV 5 axis IS when used with Olympus OM-D cameras, which also allow fast, accurate AF almost anywhere in the frame (not just near the middle and which can be activated rapidly by using the touch screen or even the touch of the Live View screen on a wifi tethered smartphone) and with ability to accurately AF on the closest eye – just awesome! And that’s not all – on the E-M1II you get continuous AF at 18fps and silent shutter, not to mention the unique Olympus Live Composite mode for doing star trails, car headlights, etc at night, and for static scenes with tripod, the ability to shoot 50mp Hi Res shots.

ps… I didn’t do this comparison with the Olympus 25mm f/1.2  lens as I don’t own one ….. yet! :)

In the end, do you really need the extra shallow DOF that full frame affords when you are giving up so much to have it?

Sony A7II full frame with Canon EF 85mm f/1.8 vs Olympus OM-D with Olympus 75mm f/1.8 lens – real world comparison images

Monday, April 24th, 2017

In an earlier blog post, I compared the Sony A7II full frame with Canon EF 85mm f/1.8 vs Olympus OM-D with Olympus 45mm f/1.8 lens in terms of how they render the background wide open at f/1.8 at approximately the SAME subject distance and approximately the same field of view. The full frame kit allows 2 stops more shallow depth of field, but for most situations, the ability to blur the background with the 45mm lens is adequate, and it does so at a much smaller size.

In this post, I tackle the photographic problem slightly differently as I tried to maintain the same subject magnification by shooting the 75mm lens twice as far away from the subject as the Canon EF 85mm lens as the 2x crop factor of Micro Four Thirds means the Olympus 75mm lens actually has the field of view of a 150mm lens in full frame terms.

These are two of the sharpest wide aperture “consumer” lenses from each manufacturer – unfortunately, neither are weather-sealed.

Thus when shooting both lenses wide open at f/1.8 at same subject magnification as outlined, one can expect for the Olympus 75mm lens, the background field of view will be narrower and more compressed (which I prefer as most Australian forest backgrounds tend to be busy, chaotic and distracting, and one can better avoid having distracting bright skies in the frame, so less background for me is better, even though it is not as blurry).

Had I shot with the background at infinity, the DOF calculations indicate that the background would be just as blurry, but when the background is quite close to the subject as in these images, the full frame does give more blurry images – but at times too blurry (although this can be addressed by stopping the aperture down but then may need to increase ISO by 2 EV if you cannot afford to have a slower shutter speed, and then the benefits of full frame are largely lost).

One big difference between the two is the far better close up magnification obtainable with the Olympus mZD 75mm lens as both have close focus of around 0.85m but the Olympus does this with twice the telephoto effect giving twice the macro.

In addition, I feel the Olympus OM-D cameras render the greens in a more pleasing way than the Sony a7II, and of course, the Olympus camera has a 4:3 aspect ratio which I think works better for portraits, while the Sony has the old, historic, narrow 3:2 ratio.

The Canon EF 85mm f/1.8 lens is a highly regarded “portrait” lens, often regarded as one of the best Canon lenses which is not a Pro L lens. It is sharp but does have some CA issues wide open. When used with the Sigma MC-11 EF-Sony lens adapter, you do get fairly fast AF but no Eye AF.

On a full frame camera such as the Sony A7II mirrorless camera, the Canon EF 85mm f/1.8 provides the user with shallow depth of field options when compared to the slightly smaller (58mm filter vs 58mm filter), lighter (305g vs 400g) Olympus micro ZD 75mm f/1.8 lens but will this really matter for most people and will the many benefits of the Olympus system outweigh the DOF benefits of the full frame system?

The Olympus mZD 75mm f/1.8 lens is regarded as one of the best lenses ever made optically and is one of my all time favorite lenses for people photography and also shallow DOF work on Olympus cameras. Unlike the 85mm lens it is optimised for mirrorless cameras and their CDAF system and thus you can have fairly fast, accurate face detection autofocus on the subject’s closest eye (if they are not moving much), which is an awesome feature indeed – this is not possible with the Canon lens.

The Olympus lens has 5EV image stabilisation thanks to the Olympus OM-D E-M1, while the Canon lens gains around 2-3 EV IS thanks to the Sony a7II (it would have none if used on a Canon dSLR).

Real world lens tests:

Let’s have a look at some images straight from camera (just resized for web viewing) with both lenses at f/1.8 as I walked around an oak forest yesterday, not really looking for great shots, but shots to show difference in depth of field and image quality between the two systems when taken from the same camera position.

The Olympus is first then the Canon, all taken at f/1.8, base ISO, with auto WB unless specified, and none had any filters applied to the lenses – both had lens hoods attached:

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I much prefer the Olympus version of the above two, gives better context and I personally find the bokeh of the Canon one a bit annoying because we have lost the definition of the trees too much leaving distracting vertical lines.

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The above was taken with “Shady” white balance.

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The following two show that if the subject distance is substantially less than the background distance, then the degree of background blurring becomes more similar with the two lenses.

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The following two were taken not with the same imagery, but I have added them anyway.

The Olympus  was with WB set to “Shady” but came out too warm – I should have taken a custom WB with a grey target to get the best rendition here.

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The foreground bokeh of this last Canon EF 85mm lens image is very distracting and busy and in fact is so annoying I would be forced to crop it out.

Each lens renders images differently even though I have tried to control subject magnification – both have nice bokeh in most cases, but you do get quite different images – sometimes in favor of the Olympus (thanks to double the background compression), sometimes in favor of the Canon 85mm (thanks to more blurring of a nearby background).

There is no “RIGHT” camera / lens combination that will suit every image – you as the photography have the decision to make as to which tool is needed – assuming you have the tools with you.

But in the end, if you had not seen the full frame imagery, most would be very happy with the degree of background blurring of the Olympus lens – it has how you use it that will determine the success of your photography.

Here is what the Olympus 75mm lens can achieve in outdoor available light portraiture:

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Shallow depth of field in photography – a double edged sword

Friday, June 1st, 2012

Back in the old film days, many photographers were plagued by the problem of not getting enough depth of field for the light on their subject and the slow film speeds of the day and no image stabilisation to allow longer shutter speeds.

Depth of field issues is one of the reasons expensive tilt-shift lenses were designed so that landscape photographers even with their cameras mounted on tripods so they could use f/16 apertures could get their whole image acceptably sharp and detailed from foreground to background.

An out of focus foreground or background in a documentary landscape can be extremely annoying for the viewer.

On the other hand if your subject is not the scenery but a discrete subject, then shallow depth of field can be used brilliantly to separate your subject from the otherwise distracting background and make them “pop” – a favorite technique of the romanticists out there.

The excitement over the great image quality and versatility of the awesome new Olympus OM-D E-M5 Micro Four Thirds camera has yet again ignited debate that as great as it is, it can’t ever achieve the shallow DOF of a full frame dSLR even though for many other purposes most people would not be able to tell the difference between a 30″ x 40″ print from either camera.

I decided to post this blog based on some recent experiences which demonstrate the double edged sword of shallow DOF – as much as I love it as a tool, it can easily work against you.

First, let’s address the technical issue of DOF.

A full frame dSLR sensor size will always give you more control over depth of field than a smaller sensor camera
in that one can choose to go deep DOF by closing aperture down further than a small sensor camera before diffraction limitations start destroying your image resolution, and one can usually go shallower DOF by choosing a wider aperture lens for a given field of view.

The advantages of full frame dSLR for shallow DOF are particularly the case for subjects taken at a distance of more than 1-2m with a wide to standard field of view lens.

For macrophotography, close up photography and telephoto photography, Micro Four Thirds will generally be able to deliver you as shallow a DOF as you need as long as you have a reasonable aperture lens.

To get the same DOF and field of view on a Micro Four Thirds camera as a full frame dSLR you need to use a lens of focal length AND aperture half that used on a full frame dSLR.

So a 24mm f/1.4 lens of a full frame camera would require a 12mm f/0.7 lens on Micro Four Thirds and that is not going to happen any time soon although there is a 17mm f/0.95 lens.

Likewise a 50mm f/1.2 lens on a full frame would require a 25mm f/0.6 and the closest we will get is a f/0.95, while most of us will settle for the lovely Panasonic 25mm f/1.4.

The Canon 85mm f/1.2 lens on a full frame would require a 43mm f/0.6 lens and again, the closest we can expect is a f/0.95 lens around that field of view range.

The 135mm f/2.0 lens on a full frame lens would require a 67mm f/1.0 lens to match it.

The 200mm f/2.8 lens on a full frame would require a 100mm f/1.4 lens and the closest we will have is the 85mm f/1.2, 85mm f/1.4, or if you need AF, the 75mm f/1.8.

So you get the picture if you place a super expensive wide aperture lens on a full frame dSLR you will nearly always be able to get more DOF control than when using a cropped sensor camera – that’s just the way it is.

BUT, this capability has it’s downsides.

1. you now have to think about your subject very carefully and decide how much DOF you need to capture it well, and thus exactly which aperture for the given lens and subject distance.

2. if you are forced to use wide aperture such as hand held shots at night, or wide aperture sports shots at fast shutter speeds, you may be plagued with the age old problem of not enough DOF and most viewers hate a blurry subject!

Let me demonstrate each of these from my own recent experience.

1st a couple of potentially stuffed up shots.

A wedding shot with a pro dSLR (almost full frame Canon 1D Mark III 1.3x crop sensor) combined with my favorite lens for this camera, the 135mm f/2.0 L lens.

Now as I have mentioned before, using the amazingly cheap Rokinon/Samyang 85mm f/1.4 on a Micro Four Thirds camera yields almost identical imagery (field of view, DOF and bokeh) as this combination at a quarter the weight, size and price, but that is another story – see here for related posts of this lens:

I generally shoot half body shots with this lens at f/2.5-f/2.8 to get sufficient DOF for my subject, so for this couple shot, I lazily just closed the aperture down a bit more to f/3.2 to give me a touch more DOF without making the background too distracting.

Unfortunately, I failed to chimp the image after the shot was taken to carefully check my DOF (it didn’t help that the Canon did not have an EVF to do this and my reading glasses were left in the car!).

Needless to say, the bride looks beautiful and sharp, but the groom is well out of focus, and I had to salvage it a bit by turning it into a romantic looking shot – luckily I was not the official photographer!


Canon example

Ah, yes, what a crappy photographer I can be sometimes! But surely I can’t get too shallow a DOF using the new Olympus OM-D E-M5 camera with its cropped sensor…

oh yes I can…..this is the 1st shot I took using the Olympus mZD 45mm f/1.8 lens playing around with the fun touch the screen on the subject and almost instant AF and shutter release:


E-M5 example

OK, it is a lovely candid shot of my mischievous kitten but closer inspection will reveal that her eyes are incredibly sharp even with this lens at f/1.8, but her nose is well out of focus – a big mistake in portrait photography – always aim to get tip of nose to ear in focus unless you are aiming for special effects like with my tilt-shift lens where one can change the plane of focus such as in the glamour portrait below:


tilt-shift example

 In summary, a cropped sensor camera will not replace the capability of ultra shallow DOF of a full frame dSLR, but a camera such as the Olympus E-M5 when teamed up with wide aperture lenses opens up new avenues for hand held low light photography whilst still maintaining an adequate DOF for your subject.

For most of us the Micro Four Thirds system when teamed with its lovely wide aperture lenses such as the 12mm f/2.0, 25mm f/1.4, 45mm f/1.8 and 75mm f/1.8 will address our shallow DOF as much as we need and for those who want to explore more shallow DOF, then they can enjoy the manual focus f/0.95 lenses, or even use the Canon 85mm f/1.2 and have them all image stabilised.