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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?

In celebration of the wonderfully smooth bokeh of the Rokinon 85mm f/1.4 manual focus lens – another demonstration of its amazing qualities

Sunday, July 31st, 2011

 
Rokinon bokeh
 

Compare all 6 images from this series – see them on my Flickr set.

The amazingly cheap Rokinon 85mm f/1.4 manual focus lens on a Micro Four Thirds camera (The Panasonic GH-1) bokeh and CA test on an extremely challenging subject – a strongly backlit wax mannequin with a multitude of highlights on the pearls – a challenge for any lens wide open – but this lens passes it easily – even with a cheap UV filter and no lens hood!

This image is to show how good the rear bokeh is for out of focus areas at f/1.4 but at closer focus than the others in this series to give even shallower depth of field – look at the pearl highlights in the rear.

AWB in artificial light.
No cropping.
RAW file with no post-processing performed other than Lightroom export with resizing and compressing for the web and its default standard sharpening.

This len gives me similar imagery to my Canon EF 135mm f/2.0L lens at f/2.0 on my Canon 1D Mark III camera at 1/5th the price and less than half the weight (see here for my comparisons) – no wonder my Canon stays at home now!

The amazing 1920′s flapper styled wax mannequin and pearl-beaded head piece belong to Ken Gray and Alister Reid Gallery of Melbourne who created the pearl jewelry and kindly consented to me photographing it in their store, as well as creating unique, high quality, individualised jewelry which can be re-fashioned from your existing jewelry – if you are in Melbourne, check their work and gallery in Collins St.

As I love this lens so much, I bought another one from Ebay tonight – this time in a Nikon mount so I have greater versatility:

I can let my friends use it on their Nikon (it is better than my friend’s mark I Nikkor 85mm f/1.4)

I can use it with AF-confirm adapter on my Canon 1D Mark III as a 110mm field of view f/1.4 (it is way better wide open than my Canon EF 85mm f/1.8 lens)

I can use it on my Four Thirds dSLR and gain image stabilisation as well as AF confirm giving me an effective 170mm field of view f/1.4 IS lens.

I can use it on my Micro Four Thirds and have easy live view magnification, and if I want, via the LensBaby Tilt Transformer, I can convert it into a tilt lens.

Brief shootout – Canon 1DMIII + EF 135mm f/2.0L lens vs Panasonic GH-1 + Rokinon 85mm f/1.4 lens

Sunday, April 3rd, 2011

One of my favorite walk around and people photography kits is the Canon 1D Mark III pro dSLR camera matched with the lovely Canon EF 135mm f/2.0L lens.

Given the 1.3x crop factor of this camera, this combination in effect gives me telephoto reach of a 176mm lens on a full frame camera.

This focal length allows me to be more versatile in selection of backgrounds by virtue of compression of the perspective, while the f/2.0 wide aperture allows one to make the subject pop by having a shallow depth of field (in most situations, a touch too shallow hence I often use f/2.5 or f/2.8 for people photography), and it renders the background with a lovely smooth bokeh.

If you are shooting into a light source, using the lens shade is a must to minimise internal lens flare which is the main issue with this lens.

My biggest problem with this outfit is that it is so big and heavy, I usually don’t bring it with me unless I have something specific in mind.

I have been searching for a similar image drawing outfit with my Micro Four Thirds camera – the now very cheap, Panasonic GH-1 (you can buy it for about a fifth of the price of a Canon 1D Mark III).

I tried the Canon EF 85mm f/1.8 lens, which although is a very nice lens, suffers from considerable purple fringing.

Last week, I received the Rokinon (Samyang) 85mm f/1.4 manual focus lens in Canon EF mount which I bought from Amazon.com for the ridiculously cheap price of $US265.

Now this lens on the GH-1 gives a telephoto reach of 170mm and a depth of field at f/1.4 similar to what my Canon outfit above would give me, furthermore, this 85mm lens is reknown for its buttery smooth background bokeh.

So how would a GH-1 kit you can now buy for well under $US1000 compare with a $US4000 Canon pro outfit?

Of course with the GH-1 you will have to resort to magnified live view for accurate manual focus but at least this is much easier than on a dSLR with its annoying mirror, and thus you may be more limited to relatively stationery subjects, but that suits me fine, as long as I can get a similar image quality at a third of the weight and size, then I will be happy.

Here are a few shots of each camera taken from identical positions at wide open aperture, hand held as I would normally take them, and focussed on similar spots with no post processing of the in-camera jpegs other than merging and then resizing and compressing for the web. Note I did not use a lens hood for any of these shots, as forgot to bring it for the 85mm so to be fair, I left it off the 135mm lens – something I would NEVER normally do for that lens! The sun was not directly hitting the lens glass in any of these images.

Click on the images for a larger view. I will tell you which is which at the bottom of this post.

shoot out 1

shoot out 2

shoot out 3

OK, have you decided which you would prefer or are they both similar enough you would be happy to use either?

1st image, the Canon is the top one, while the other two images, the Canon is the image on the left (with the unfortunate vertical line I stuffed up in my editing of the files, and I apologise too for the jpeg compression artefacts – I am not used to Corel’s software which I have had to resort to as my laptop with PS on it just died).

In the 2nd image taken late in the afternoon, the Canon 1D Mark III rendered it a lot cooler than in reality.

The important point in these images is how the background is rendered – almost identical – and that purple fringing is not problematic in any of these.

I think I am on a winner here with this 85mm lens – and it has manual aperture control, plus I can use it on the Canon 1D Mark III if I wish.

I can’t see much difference between the two, other than the more contrasty rendition by the Panasonic (I forgot I had it set to Dynamic Film Mode), and perhaps the 85mm lens draws out of focus foregrounds less well, and it may be a touch less sharp wide open.

For those who are budget challenged, or who just want a small kit to carry around, the Rokinon 85mm f/1.4 is worth a look at that price!

For those who need 10fps, relatively fast AF, weatherproofing, TTL flash, remote TTL flash, or flash sync 1/500th sec (with Pocket Wizards) for outdoor fill in flash in the sun at wide aperture, then you will have to keep your Canon kit as the Panasonic outfit just won’t cut it on these requirements.

10x zoom lens comparison – Canon, Nikon, Tamron, Olympus and Panasonic Micro Four Thirds

Saturday, July 3rd, 2010

Many people are looking for a travel or general use / walkabout camera with higher image quality than point and shoots but with a single 10x zoom lens.

So I thought I would amalgamate the lens review results over at the excellent dpreview site as they appear to have relatively good standards for testing which should allow reasonable comparisons of their results. In doing so, I have tried to estimate values from the charts for each lens at their widest aperture, and compared them at approximately equivalent field of view focal lengths – not their native focal lengths.

I have chosen the 5 common zoom lenses likely to be considered for cropped sensor cameras (none of these lenses are applicable to full frame dSLRs):

  • Olympus M.ZD 14-150mm f/4.0-5.6 ED for M43
  • Panasonic Lumix G 14-140mm f/4.0-5.8 OIS HD for M43
  • Canon EF-S 18-200mm f/3.5-5.6 IS
  • Nikon DX 18-200mm f/3.5-5.6 VR
  • Tamron 18-270mm f/3.5-6.3 VC macro for EF-S or DX

Clearly from these tests, if you want a light, compact lens with very good image quality and the sharp macro image quality with minimal aberrations, the stand out lens is the new Olympus M.Zuiko Digital 14-150mm f/4.0-5.6 ED, although if HD video is critical to your needs, the heavier, more expensive, and even sharper, Panasonic Lumix HD G HD 14-140mm F4-5.8 OIS may be the better option, particularly if you choose a Panasonic Micro Four Thirds camera instead of an Olympus one.

Note that the Panasonic M43 cameras use in-camera optical corrections and the CA results with the Lumix lens is actually neglible after correction (the figures in the table are uncorrected and would apply if the lens is used on an Olympus camera).

Both Panasonic and Olympus cameras are correcting the barrel distortion of their lenses and the table shows the corrected values.

Compared to the Canon, Nikon and Tamron EF-S/DX lenses, the Olympus M.Zuiko Digital 14-150mm f/4.0-5.6 ED lens is:

  • half the weight
  • significantly shorter
  • uses a nice 58mm filter thread instead of more expensive 72mm filters
  • is MUCH sharper edge-to-edge at practically all focal lengths at wide open apertures
  • has much nicer macro image quality
  • nicer bokeh quality
  • no zoom creep (although the zoom is a little stiffer)
  • has comparable levels of CA
  • neglible distortion due to in-camera corrections.
  • importantly, for the rapidly increasing use of these cameras for video work, the lens has been optimised to reduce AF noise being captured by the camera microphones.

This Olympus lens shows that you can have your cake and eat it too!

Of course, it is not going to give the same results as a pro quality f/2.8 zoom lens, but these lenses are a totally different size, weight and expense category.

Perhaps now you can understand why I am loving the Micro Four Thirds camera system – you can take more lenses and cameras with you for the same size and weight, which means, more fun!

Furthermore, with the new firmware hack for the Panasonic GH-1, this camera will now give the highest quality HD video of all the dSLRs.

When you want really small and light, you have the options of the excellent Panasonic 20mm f/1.7 pancake lens or the cheaper Olympus 17mm f/2.8 pancake lens.

There are a couple of caveats however:

  • if your main aim is capturing fast moving subjects, the Micro Four Thirds system does not currently auto-focus fast enough, and thus you will have to resort to pre-focusing, or resorting to a dSLR such as a Four Thirds Olympus E-30 or E-3 (lenses will be relatively compatible with your Micro Four Thirds camera), or a higher end dSLR from Canon, Nikon, etc. However, all of these 10x zoom lenses are a bit sluggish to AF at telephoto end on moving subjects, so you would probably need a lens better designed for sports anyway.
  • if you also want to use large f/2.0 or f/2.8 zoom lenses, you need a bigger dSLR to make them easier to hold.

If you do decide to go with Canon or Nikon cropped sensor dSLRs, the Tamron lens offers 15x zoom with reasonable image quality.

NB. MTF-50 is an indicator of sharpness, the higher the figure, the better it is.

NB. 10x zoom lenses should not be expected to give nice smooth bokeh quality, and these lenses show this, however, it would appear that the Olympus lens gives the most pleasing bokeh of the five lenses.

Oly M.ZD Pan M43 Canon Nikon Tamron
focal range 14-150 14-140 18-200 18-200 18-270
aperture 4.0-5.6 4.0-5.8 3.5-5.6 3.5-5.6 3.5-6.3
Price $US600 $US790 $US699 $US680 $US629
weight (g) 280g 420g 600g 560g 560g
length (mm) 83-142 83-142 102-162 97-162 101-190
Filter (mm) 58mm 62mm 72mm 72mm 72mm
35mm eq. zoom (mm) 28-300 28-280 29-320 27-300 29-432
close focus (m) 0.46m 0.5m 0.35m 0.5m 0.42m
macro mag. 0.25x 0.2x 0.31x 0.26x 0.32x
MTF-50 at max. apertures
28mm centre 1550 1900 1200 1300 1200
28mm corner 700 760 400 725 650
100mm centre 1450 1450 1450 1100 1500
100mm corner 850 1000 750 450 750
200mm centre 1400 1200 1000 750 1125
200mm corner 700 750 400 460 650
300mm centre 1125 1250 1125 1000 1100
300mm corner 650 700 700 650 600
max. CA at corners
28mm 0.13% 0.12% 0.11% 0.14% 0.08%
200mm 0.14% 0.08% 0.09% 0.10% 0.02%
300mm 0.11% 0.16% 0.22% 0.16% 0.16%
distortion 28mm +1.2%# +1.6%# +3.4% +2.8% +3.5%
max pincushion nil# nil# -1.9% -2.3% -2%
best native focal lenth 25mm 25mm 50mm 24mm 50mm
bokeh the most pleasing
ok? ok bokeh harsh bokeh ok bokeh
macro IQ nice macro IQ nice soft macro soft macro soft macro
zoom creep nil nil ? yes yes
notes HD video silent AF

IS via camera

HD video silent AF

IS

Stepless aperture

IS IS IS

Other 10x zoom lenses:

  • Ricoh GXR P10 lens kit 28-300mm f/3.5-5.6 VC – but only a tiny sensor in this lens
  • Samsung 18-200mm OIS / F3.5-6.3 for its NX mirror-less cameras – not yet available ? 2011
  • Sony NEX 18-200mm f/3.5-6.3 OIS for the NEX mirror-less cameras – not yet available
  • Olympus ZD 18-180mm f/3.5-6.3 ED - consumer grade Four Thirds lens gives 36-360mm coverage and weighs only 440g and costs $US499
  • Sigma 18-200mm f/3.5-6.3 DC OS HSM – cropped sensor lens; less distortion and CA than the Canon, Nikon and Tamron lenses displayed in the table above, but not as sharp as them, and with less effective IS.
  • Sigma 18-250mm f/3.5-6.3 DC OS HSM – cropped sensor lens; not as sharp as the Tamron but faster AF and better build.
  • Canon EF 28-300mm f/3.5-5.6 L IS USM – pro grade full frame introduced in 2004 but weighs 1.7kg and costs $US2420
  • Sigma 50-500mm f/4.5-6.3 OS HSM full frame - introduced in 2010, available in Canon, Nikon, Pentax and Sony versions but uses a 95mm filter, weighs 2kg and costs $US2400! There is an older non-IS version of this lens. Personally, I would go for a smaller, lighter 4x telephoto zoom with better image quality, but some people may need such a lens.

Another alternative – wide aperture 3-5x zoom lens with 2x teleconverter:

  • Olympus ZD 50-200mm f/2.8-3.5 with EC-20 2x teleconverter
    • provides 100-400mm range at f/2.8-3.5 and 200-800mm range at f/5.6-7.0 image stabilised with Olympus camera bodies, pro grade and weighs only 1kg excl. tripod mount and EC-20
    • ie. equates to 100-800mm f/2.8-7.0
  • Olympus ZD 90-250mm f/2.8 with 2x teleconverter
    • provides 180-500mm range at f/2.8 and 360-1000mm range at f/5.6, super pro grade and weighs over 3kg but that is much less than anything in the Canon or Nikon line up for similar telephoto reach.
    • ie. equates to 180-1000mm f/2.8-5.6
  • Canon or Nikon 70-200mm f/2.8 IS/VR with 2x teleconverter
    • provides 70-200mm range at f/2.8 and 140-400mm range at f/5.6 image stabilised but weighs 1.7kg
    • ie. equates to 70-400mm f/2.8-5.6 or 112-640mm on a 1.6x cropped sensor Canon

Since writing this post, Nikon released their full frame Nikkor AF-S 28-300mm f/3.5-5.36 ED VR II G lens for €899 or currently about $US999 which gives a great option for Nikon D700 users in particular:

  • made in Thailand, it obviously provides 28-300mm coverage in 35mm full frame terms but also 42-450mm when used on a DX crop camera.
  • close focus to 50cm
  • zoom lock switch to prevent zoom creep, and 9 rounded aperture blades
  • it is too noisy for recording video while it focuses, but then you probably wouldn’t use a current Nikon dSLR to do high quality video anyway.
  • 2 ED and 3 aspherical elements but no optical performance reports to date
  • it is said to be sharp and certainly seems much sharper than the Nikkor 70-300mm and the DX 18-200mm but less sharp than the pro lenses or the primes as would be expected
  • it has lots of distortion at focal lengths other than 35mm – “Distortion is strong barrel at 28mm, none around 32mm to 35mm, strong pincushion midrange and mid-tele, and moderate pincushion at 300mm”.
  • bokeh seems reasonable
  • the lens hood looks a bit dysfunctional and I suspect many will leave it at home
  • 77mm and weighs 800g – less than half the weight of the Canon 28-300mm L lens, but still not a light lens to carry all day – it is still twice as heavy as a Micro Four Thirds Panasonic option and almost 3x heavier than the Olympus option!
  • Ken Rockwell loves this lens but does state: “If you don’t mind the hefty size, this 28-300mm is perfect. I wouldn’t enjoy traveling with it, and it is perfect for use on a dedicated photo trip”
  • for a full frame user who can’t afford the faster aperture pro lenses, it will give a lot of versatility with somewhat faster AF and better high ISO performance than a Panasonic GH2 with 14-140mm lens, but at significantly more weight, bulk and without the superb HD video capabilities or automatic distortion correction capabilities of the GH2.
  • at the end of the day though, a substantial point of having a full frame dSLR is not only for high ISO performance but shallow depth of field work, and full frame users are still likely to want their heavy, large 70-200mm f/2.8, 24mm f/1.4, 50mm f/1.4 and 85mm f/1.4 lenses with them as well so perhaps the 28-300mm may in fact be redundant for most, and they would be better suited to having a GH2 with 14-140mm lens instead as a 2nd camera for travel and video work.
  • I suspect this lens is a wonderful marketing ploy by Nikon which entices new users to a full frame dSLR at a reasonable price point with the delusion that this lens will be all they will need or want, only to find it does not have the aperture they need, nor the AF speed, and so they end up having this lens becoming redundant – too big for carry around or travel and not good enough for their needs. But by then they are committed to the Nikon system and spending more money – a very nice marketing ploy indeed!

Micro Four Thirds and ability to blur the background

Monday, December 28th, 2009

One of the common misconceptions is that you need a large sensor to blur the background, and the 2x crop factor of the Four Thirds and Micro Four Thirds cameras makes it harder to blur the background.

It is true that the 2x crop sensor means depth of field for the same subject magnification will be deeper for the same aperture, thus the depth of field at the same subject magnification using a 25mm f/1.4 lens will be similar to using a 50mm f/2.8 lens on a 35mm full frame camera.

HOWEVER, the mathematics of background blurring is DIFFERENT to the mathematics of depth of field.

Let’s have a look at this visually.

I have set up a little Christmas themed scene and aimed to keep the subject the same size in each image (the large one is ~8″ tall, while the middle one on which focus is set is ~5″ tall) and see what happens to the blurring of the background Christmas tree ornaments.

The Panasonic GH-1 makes this a little easier as you can use a native 3:2 image aspect ratio, the same as on my Canon 1D Mark III which has a larger sensor (1.3x crop factor compared with 2x for the GH-1).

Let’s have a look at what the Canon 1D Mark III can do with an Olympus OM 35mm f/2.8 lens at f/2.8 giving an effective focal length of 46mm and similar DOF to 46mm f/3.6 on a 35mm camera:

1DMIII 35mm f/2.8

Now for the same effective focal length on a Panasonic GH-1, firstly, an Olympus OM 24mm f/2.8 lens at f/2.8:

GH1 24mm f/2.8

Not bad, the background blurring is almost as good as in the Canon image (note also the different colour rendering even though using AWB and default picture modes).

But let’s see what we can achieve on the GH-1 with a Leica-D 25mm f/1.4 lens which in DOF terms should be similar to a 50mm f/2.8 lens on a 35mm full frame camera:

GH1 leicaD 25mm f/1.4

Wow, beautifully smooth bokeh, and much smoother than one would expect from the DOF equivalences alone.

And for comparison, the GH-1 with OM 35mm lens at f/2.8 (equiv. to 70mm focal length in 35mm film terms), with camera moved further away to maintain same subject magnification:

GH1 OM 35mm f/2.8

Other than the change in perspective (ie. less background visible) compared with the Canon image at the top of this post, the background blurring is very similar.

This is why so many people are loving the Panasonic 20mm f/1.7 lens – it is sharp, very compact, much cheaper than the Leica 25mm, perfect for social events and candid photography, gives a fast aperture for low light work and to top it off, allows nice background blurring at f/1.7 – better than a Canon 24-105mm f/4L lens and similar to, if not better than the Canon 24-70mm f/2.8L lens and the f/1.7 aperture nullifies any high ISO advantage of the larger format cameras when they are using f/2.8 or f/4 lenses.

Of course, Canon 1D users can resort to 35mm f/1.4 lenses, and Canon / Nikon full frame users can resort to a 50mm f/1.2 or f/1.4 lens to give even more background blurring at this effective focal length, but the result is a much bigger, heavier, more intimidating, less discrete and more expensive system.

Canon, Olympus and Panasonic Lens Tests on the Panasonic GH-1

Tuesday, September 22nd, 2009

A few posts ago, I discussed results of my simplistic lens tests (photographing a lens resolution chart at variable distances according to effective lens focal length to keep chart size almost constant with careful live view magnified manual focus on tripod with self-timer).

I have now placed double-sized crops (ie. cropped the centre of the images and uploaded using PS to double the size of the image which equates to viewing these images at “200x” in PS and then compressed them to 29% jpeg compression) of these images on my website here so that you can get a better idea.

Most people do not like looking at photos of lens resolution charts, so if you fall into this category, then don’t look, just check out the photos I take with the lenses here instead.

The main conclusions of the tests were posted in these blogs:

In the previous post of the EF 85mm lens in action, Jeff commented on the purple fringing and whether it is sensor blooming rather than chromatic aberration given the absence of green fringing as well.

From the lens tests, the new ED glass lenses such as Canon L lenses and Olympus ZD 50-200mm lens had minimal if any purple fringing even wide open.

In comparison, older legacy lenses (even the EF 85mm f/1.8) with no ED glass showed much purple fringing but no green fringing wide open which tended to improve substantially as one stopped down.

Thus I suspect it is not sensor blooming per se that causes this but perhaps an interaction between the sensor microlenses and chromatic aberration or perhaps lack of telecentricity of the lenses which tends to be worse wide open.

I have older lens tests using the same technique here (but chart magnifications may not be identical to that above so may not be directly comparable):

Lens tests II – 85mm and 100mm focal lengths

Friday, September 4th, 2009

Following on from my last post where I tested lenses at 135mm focal length on the Panasonic GH-1, I have performed the same tests using lenses at 85mm focal length but with camera moved closer to the target to maintain the target magnification at a constant.

All performed on tripod with self-timer.

In order of resolution (best to worst):

  • Olympus ZD 50-200mm f/2.8-3.5 SWD at 85mm at f/3.1, f/4, f/5.6 (little difference between them) – almost no purple fringing even wide open
  • Canon EF 24-105mm f/4L IS at 100mm at f/4 – almost no purple fringing
  • Canon EF 85mm f/1.8 at f/1.8, f/2.8, f/4 – all very sharp, but severe purple fringing at f/1.8, moderate at f/2.8 and almost gone by f/4.0
  • Olympus ZD 50mm f/2.0 macro + ZD EC-20 2x teleconverter – some CA though
  • Panasonic Lumix 14-140mm f/4-5.8 HD at f/5.8 – not far behind the others, but definitely a touch softer
  • Olympus OM 100mm f/2.8 – but very compact, and a great option at f/4 or f/5.6 when it becomes as good as the Lumix albeit without optical image stabiliser but the extra aperture will partly compensate

Interestingly, although not surprisingly, the Canon EF 135mm f/2.0L on a tripod even wide open gave more image detail than any of these lenses (but only just), even when placed further away to ensure the same subject magnification. And, it achieved this with almost no purple fringing – just remember, this lens really needs to have the lens hood on as internal flare tends to be a problem which lowers image contrast.

For its size and versatility, the Panasonic Lumix does at good as most people need, and I would expect the differences in resolution to disappear once you hand hold them.

The Olympus ZD 50-200mm is just a great lens and has the advantage over the Panasonic of not only being sharper with less CA but wider aperture (f/3.1 vs f/5.8 at 85mm) however, is best suited to an image stabilised Olympus Four Thirds dSLR given its size and weight, and lack of AF on the MFT.

The Canon EF 85mm f/1.8 lens is a very well regarded Canon lens – said to be the best of the non-L lenses, and this test showed it was very sharp even wide open. Unfortunately, as is the case with most legacy film lenses, it shows very severe purple fringing at f/1.8 which is still a bit annoying at f/2.8.

I had hoped the Canon 85mm would have made a nice portable wide aperture lens for the Panasonic GH-1 or, better still the Olympus E-P1 with its image stabiliser, but unless you want to post-process all that purple fringing, I think other options may need to be sought.

For comparison, I also tested the beautifully compact Olympus OM 100mm f/2.8 lens a little further away to maintain subject magnification. It was not quite as sharp as the Lumix lens at f/2.8 and f/4 but very close by f/5.6 – in the field, hand held, the differences would not be an issue. Purple fringing was problematic at f/2.8 but acceptable at f/4.

Thus the OM 100mm f/2.8 would be more suited to the Micro Four Thirds than the EF 85mm f/1.8 given its compact size, ability to change apertures and is best used at f/4 or f/5.6, but at least it offers a very compact 200mm f/4 lens in 35mm focal length reach with the option of opening it up to f/2.8 if you had to.

If you were going to take the EF 85mm f/1.8 lens for a little more sharpness than the Lumix or OM 100mm, I would set it at f/2.8 (some purple fringing but better than the OM 100mm at f/2.8) or f/4 (minimal purple fringing).

See some of my photos taken with the GH-1 and OM 100mm f/2.8 lens combo here.

Lastly, I thought I would compare the superb Olympus ZD 50mm f/2.0 macro lens mated with the ZD EC-20 2x teleconverter to make 100mm actual focal length as with the Olympus OM 100mm f/2.8 lens.

This combo even wide open at f/2.0 (f/4.0 for exposure measurement when taking into account the 2x TC), was as sharp as the EF 85mm f./1.8 but showed some CA at f/2.0, f/2.8 and even at f/4 – again, hand held, I would opt for the more compact OM 100mm f/2.8 for use on the MFT cameras.

See photos taken with the 50mm f/2.0 macro plus EC-20 2x TC here, taken with the Olympus E510 dSLR.

Some lens resolution tests on the GH-1 at 135mm focal length

Friday, September 4th, 2009

With the Canon 7D coming out with almost the same sensor photo-site density as the Micro Four Thirds and the Four Thirds sensors (which equate to ~48 megapixels on a 35mm full frame sensor), I thought the 7D may be pushing the Canon lenses given they are not specifically designed for this density as are the Olympus ZD lenses.

Now that I can test my Canon lenses on the same sensor (the Panasonic GH-1) as my Olympus and Panasonic lenses, I thought it is time for a quick test.

So I thought, let’s start at one of their best prime lenses – the Canon 135mm f/2.0 L- if this can’t cut it, then Canon users can forget about getting any resolution benefits from the 7D and their zoom lenses!

I won’t bore you with the charts, but I tested it by setting the GH-1 at ISO 200, IS off, default settings in manual exposure (with same metering for each exposure), on a tripod with magnified live preview manual focus and 10 sec self timer. Photos were taken at the same distance and focal length of a lens resolution chart at 10 meters. No lens filter in place.

I only looked at resolution, not other aberrations.

In order of resolution (best to worst):

  • Canon EF 135mm f/2.0 L lens at f/2.8 and f/4.0
  • Canon EF 135mm f/2.0 L lens at f/2.0 and f/5.6
  • Olympus ZD 50-200mm f/2.8-3.5 SWD at f/5.6
  • Olympus ZD 50-200mm f/2.8-3.5 SWD at f/3.3
  • Canon EF 135mm f/2.0 L lens or Olympus ZD 50-200mm at f/8
  • Canon EF 135mm f/2.0 L lens at f/2.8 but HAND-HELD at 1/500th sec
  • Lumix 14-140mm HD f/4-5.8 at f/8
  • Lumix 14-140mm HD f/4-5.8 at f/5.8, f/6.3

There was not a lot of difference between them all, but there was a definite difference, and the results are much as you would expect, with the top of the range Canon L prime lens just edging out the beautiful, versatile Olympus ZD 50-200mm lens.

As was suggested by dpreview.com’s lens test of the Lumix 14-140mm lens, whilst this lens gives really excellent results at 18-50mm, it is a little soft at the long end, and this was born out in my tests.

Certainly it suggests that diffraction limitations cause resolution to be impaired at f/8 compared with wider apertures, although the Lumix actually was best at f/8 as it was a touch softer wide open at f/5.8.

NOW, to put the cat amongst the pigeons.

I took the camera off the tripod and did some hand held tests as ISO 800 (in order to keep some sort of shutter speed for what is really 270mm focal length reach in 35mm terms). Checked that using ISO 800 in itself didn’t impair detail – and it didn’t.

First, I tested the Canon 135mm L lens hand held at 1/500th sec – surely that should be sufficiently fast with my reasonable ability to hand hold a camera.

WOW, 1/500th sec, f/2.8 and sharpness of the Canon lens dropped off to the level of the Lumix lens at f/8!!

So, then I put my Lumix lens back on and tested it hand held at ISO 800, f/5.8 but now, I had to drop shutter speed to 1/100th sec in the same lighting – result with image stabiliser – AWFUL – converted the 12mp image into a 1-2mp one in terms of detail.

Turned the image stabiliser on in the Lumix lens, re-took the photo, and as expected, MUCH better, but still not quite as good as the results on the tripod!

MORAL of the story, the Canon 135mm f/2.0L lens is really sharp even wide open, but even better at f/2.8 and f/4, BUT if you hand hold it at shutter speeds 1/500th or slower, you may as well be using it on a 5-10mp camera because you lose detail, and unfortunately, Canon and Nikon still refuse to put an image stabiliser into their bodies.

I would suggest that if you are going to hand hold the Canon 135mm f/2.0L lens at less than 1/500th sec, and you are happy to use it at a fixed aperture and in manual focus, then the sharpest images will not be from a 18mp Canon 7D but from a 12mp Olympus E-P1 with it’s in-built image stabiliser!

If you want more than 12 mpixels of details out of your camera, then unless you use a very fast shutter speed, you need to put it on a tripod – perhaps the Sony full frame dSLRs with their in-built IS will give much more detail hand held than a Canon or Nikon full frame?

Camera shake effectively converts your expensive lens to a cheap lens and in the process could convert your high megapixel sensor into a low megapixel sensor but with big file sizes.

See some of my hand held photos taken with the GH-1 and EF 135mm f/2.0L combo here.