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Amazing multicoloured bioluminescent Ghost Fungi mushrooms at night under an auroral glow

Saturday, May 27th, 2017

I went for a bush walk in a rather remote Victorian forest today and, unexpectedly, stumbled across an isolated patch of Omphalotus Nidiformis mushrooms – the “Ghost Fungi” which give off a very dim eerie glow in the forest at night (to our naked eyes without colour vision, using only rods in the dim light, they appear white).

He they are just after sunset taken hand held with the Olympus OM-D E-M1 II Micro Four Thirds camera with Olympus mZD 25mm f/1.2 lens (jpegs straight from camera just re-sized for web):

Ghost fungi

The above was hand held resting on my thigh at 1/4sec, f/3.5, ISO 1250.

Ghost fungi

The above was hand held resting on my boot at 1/4sec, f/2.5, ISO 640.

Ghost fungi

The above was hand held resting on my thigh at 0.6sec, f/4.5, ISO 1250.

So, hoping I was correct, I headed back into the closest town, had a quick bite, then headed back well after twilight had finished, and there they were, once my eyes had adjusted to night vision, the patch of fungi giving off their strange light.

Here are a few I shot with the Olympus OM-D E-M1 mark II with Olympus mZD 25mm f/1.2 lens sitting on a towel as a support (jpegs straight from camera just re-sized for web – no light painting or artificial lights, and white balance for these was set to sunny day):

Ghost fungi

The above was at f/2.8 (trying to get some more DOF), ISO 1600, noise filter = LOW, long exposure NR on with an 8 minute exposure using the very handy Live Timed function (I didn’t bring a remote to activate a BULB mode – thankfully the OM-D’s don’t need one!) and shows some lovely orange as well as green, with the top left corner being the brighter night sky (perhaps 2 stops brighter) illuminated by an Aurora Australis or Southern Lights.

The still night air without a breeze to be felt allowed me to use these nice long exposures, rather than having to open the aperture up to f/1.2 and loose depth of field even more than I was losing.

I could just imagine all the local insects coming out to dance and sing under the soft light – but it was too cold for most of them tonight – which saved me getting a few bites at least!

Ghost fungi

The above was as for the previous one but f/2.0 at 4 minutes exposure.

And, finally, just for a little fun at 10pm on a winter’s night, all alone in a remote forest, a fisheye view – taken with the unique Olympus mZD 8mm f/1.8 fisheye lens sitting on a towel at f/1.8, ISO 1600, 2 minutes to avoid the bright auroral sky washing out – and yes, you can tell it is looking south from the out of focus star trails making an arc around the South Celestial Pole somewhere near the centre of the image.

Ghost fungi

Camera settings for shooting these ghost fungi at night:

  • I used a 25mm lens (50mm in full frame terms) but one could go wider than this
  • getting adequate depth of field while keeping ISO low and exposure duration a minimum is a challenge without resorting to complicated post-processing focus stacking techniques – for the 25mm Olympus lens I prefer the f/2.8 setting but this required 8 minutes exposure at ISO 1600, if using an equivalent 50mm lens on full frame this would require using f/5.6, 8 minutes at ISO 6400 – so any high ISO benefit of full frame is lost.
    • if it is windy, then you will not be able to achieve nice imagery, even if you chose to shoot at f/1.2 and ISO 12800 to gain a shorter shutter speed, it may still be too long if the fungi are moving – go on a still night without wind, and suffer the pea soup fog on your drive home.
    • if you can’t shoot BULB (you didn’t buy an Olympus and you forgot your remote control), then you may need settle with f/1.8, ISO 6400 and 30secs
  • manual focus and a torch is a must – and it helps if your lens has a nice MF clutch, and your camera can do magnified view to allow you to accurately manual focus using a torch to assist
  • I chose to shoot sunny day white balance as I wanted to see what the colours were like compared to our normal visual experience of a sunny day
  • Noise filter should be set to LOW or OFF as ideally you should be removing noise in post-processing (I haven’t done this in these images – I will wait til I get a chance to process the RAW files)
  • Long exposure noise reduction should be set to Auto or ON – this does double the length of waiting for exposure to finish but it removes the thermal noise and you don’t need that!
  • I decided not to use my tripod as I wanted to be at ground level so i rested the camera on a towel
  • turn IS OFF
  • If you don’t have an Olympus camera then you will need to bring a remote trigger for your BULB mode to get past 30secs

The Olympus OM-D E-M1 Mark II with 25mm f/1.2 is great for this type of photography as:

  • the image stabiliser is fantastic when using it hand held for the dusk shots
  • ISO 1600 or 3200 is usable, and that is all you really need for the night shots
  • the flip out LCD screen means you don’t have to get down level with the camera on your stomach and get real dirty or have crawlies all over you
  • the 25mm f/1.2 not only is an amazing lens which focuses twice as close as similar full frame lenses, but it has a wonderful manual focus clutch
  • accurate manual focus is easy using magnified view mode
  • noise reduction phase displays a count down so you know how long you have left
  • if your torch is getting dim, you can have the Live Timed mode automatically activate Live Boost so you can see in the dark better
  • normal timed exposures go to 60 secs not like most other cameras where you need a remote control to activate BULB mode to get past 30secs
  • Live Timed mode allows you to visualise how the image is developing (eg. every 30 secs):
    • if you stuffed something up like composition, just terminate the exposure rather than wait until your planned exposure finishes
    • you can see how the histogram and image exposure is devloping, and then terminate when desired – this is how I chose to terminate the fisheye shot – when I saw the sky was starting to blow out
    • unlike BULB mode, you can set a duration for it to last and it will self-terminate the exposure without you having to be there with a remote control – this allows you to use another camera to do something else such as take Milky Way astroscapes while you wait 16 minutes for an 8 minute exposure and 8minute dark frame.
    • you don’t need a remote control – just wait for it to time out or press the shutter button to terminate exposure.
    • you can see from 5m away what the status is – is exposure still occurring or is it in noise reduction phase when its OK to turn torches on, or is exposure complete

For more mushrooms, see my previous post

Is this the biggest documented Amanita farinacea (Australian Flour Lepidella) mushroom – cap of 30cm diameter?

Sunday, May 21st, 2017

It’s Autumn in Australia and mushroom time.

I stumbled upon an amazing white mushroom in a Eucalypt forest at altitude around 800m on Mt Macedon in Victoria after the rains which was so big and white with a veil of delicate frills all around blowing in the wind and white drops on the ground nearby (hence the Flour in its name)  that it looked like it was artificial and someone had just dropped a can of white paint on to it!

As I understand it, all species of Amanita mushrooms have white gills underneath, and most are poisonous – these ones are not likely to be fatal, unlike the Death Cap (Amanita phalloides) with its amanitin toxins which destroy the liver in a few days.

Amanita Farinacea

The gigantic Amanita farinacea mushroom was adjacent a massive Eucalypt tree – I placed my iPhone 6s for reference and although I did not have a ruler, the cap of it measured at least 30cm in diameter – this species is usually said to grow to 10cm diameter.

A few days later, I found a more juvenile specimen some 10 meters away which stood some 6″ tall and perhaps 4-5″ in diameter:

Amanita Farinacea

Both of the above were taken in low light at dusk, hand held with the Olympus OM-D E-M1 II Micro Four Thirds camera and Panasonic Leica-D 25mm f/1.4 lens for Four Thirds, the first image shot at f/2.8, ISO 800 and 1/20th sec while the second image was shot at f/5.6, ISO 800 and 1/30th sec.

Some more common poisonous Amanita mushrooms:

Everyone’s favorite fairy tale fantasy mushroom – the colorful, warty, Fly Agaric (Amanita muscaria) from an oak forest:

Amanita

Olympus OM–D E-M1 II with Olympus mZD 75mm f/1.8 lens at f/1.8, ISO 200 and 1/100th sec.

The Fly Agaric is likely to cause delirium, hallucinations and possibly coma and seizures within 2hrs of ingestion – if someone was stupid enough to try eating one.

and presumably a related couple in a pine forest:

Amanita

The above was taken in very low light under dense pine forest canopy hiding adjacent to a fallen tree trunk, taken hand held with the Olympus OM-D E-M1 II Micro Four Thirds camera and Panasonic Leica-D 25mm f/1.4 lens for Four Thirds – f/2.5, ISO 500, 1/10th sec – thanks to the awesome image stabilizer in the E-M1 II.

And, who can resist some fall foliage?

foliage

The above was taken in very low light at dusk under a canopy of trees, taken hand held with the Olympus OM-D E-M1 II Micro Four Thirds camera and Panasonic Leica-D 25mm f/1.4 lens for Four Thirds – f/1.4, ISO 200, 1/15th sec – again, thanks to the awesome image stabilizer in the E-M1 II.

 

 

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:

lenses

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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?

The intricacies and complexity of lens design – interview with designer of the Olympus 25mm f/1.2 lens

Thursday, April 27th, 2017

If you can get past the Google translate issues, it is worth having a read of this interview with Olympus lens designer published on DC.Watch.

Olympus is embarking on a series of high performance “PRO” level metal, weathersealed, f/1.2 prime Micro Zuiko Digital (micro ZD) lenses with MF clutches, capable of withstanding professional “abuse” for Micro Four Thirds, now that the system has matured and many of the cameras have 1/8000th sec shutter speeds to allow f/1.2 in bright conditions without having to resort to use of ND filters or polarisers.

The following is my summary adopted from this interview.

Lens design is always a compromise!

F/1.2 was chosen instead of a wider aperture in order to keep the lens size down, AF speed fast and cost down – all of which are important for users.

The larger the lens elements, the slower the AF response as it takes more effort from the AF motors to move them.

The current f/1.8 “PREMIUM” range of lenses (17mm, 25mm, 45mm, and 75mm) were optimised for Olympus PEN camera users, but these lenses are not weathersealed.

The Olympus mZD 25mm f/1.2 lens has a an amazing lens design of 19 elements in 14 groups including 1 Super ED lens, 2 ED lenses, 3 HR Lenses, 1 E-HR lens and 1 Aspherical lens with 1 small lens element (the 5th group lens) being used for fast AF that can be moved with high frequency and precision, yet be silent. It uses a retrofocus design in which the front 3 groups produce a negative power which reduce achromatism while the rear groups produce a positive power with the master lens being in front of the AF lens. As aberration fluctuates as the AF lens moves, these variations in aberrations are reduced by increasing the number of lens elements and then controlled by multiple correction lens in the rear groups which also add back in some spherical aberration to improve bokeh and also form a sound barrier to the moving lens helping to create a silent AF system

Design principles included:

  • fast, silent AF optimised for CDAF and PDAF and satisfy the Olympus MSC standard (Movie and Still Compatible)
  • weathersealed
  • robust
  • MF clutch mechanism
  • optimising MTF at low frequency and edge-to-edge high frequency detail to provide contrast and aesthetics, particularly with portraits
  • aim for twice the MTF accuracy of a 35mm full frame lens
  • maintain the shape of Newton rings (An interference fringe of light which is generated when a lens having the opposite curve is superimposed on a certain lens) as constant as possible
  • optimising the quality of blur (bokeh) with aim for blur to “bleed slowly” but maintain resolution
    • use of a front aspherical lens to reduce incoming light to zero spherical aberration
    • adding a lens element to restore some spherical aberration at the expense of some high frequency MTF resolution
  • eliminate coma aberration – avoid use of lenses which sharply bend light as these introduce too much coma aberration – hence the need to use many lens elements to gradually modify the light rays
  • minimise all other aberrations such as distortion to reduce the extent of jpeg in-camera corrections needed but where needed, optical characteristic data corresponding to the aperture value, focus position, and zoom position is sent from the lens to the camera body and corrected by image processing.

 

In search of shallow depth of field normal “50mm” lens performance – the new Olympus 25mm f/1.2 lens

Sunday, October 30th, 2016

Once upon a time, in a different photography universe, before digital cameras, and before there were computers to design good zoom lenses, in the 1970s, nearly every camera user with a reasonably good 35mm camera bought, as a base kit, the full frame 35mm film SLR with a “standard” 50mm lens – if one was on a budget, it would be f/1.8, if one had a significant more cash flow, it would be f/1.4 and if one was rich, then a f/1.2 lens.

They then added to this kit with a wide angle lens (usually a 28mm f/2.8 or f/3.5, or if they had the money, a 24mm f/2.8) and a prime telephoto lens (usually 135mm f/3.5 or if they had the extra money, f/2.8).

All of these were manual focus only lenses, and some of the SLRs such as the Olympus OM-1 actually worked without batteries (although the meter would not work).

So common was the 50mm f/1.8 lens that experienced photographers often shunned using it because everyone had that look and so they migrated to other focal lengths such as 21mm, 35mm, 40mm, and 85mm.

But what these entry level cameras gave their owners was shallow depth of field at 50mm (albeit with rather soft images wide open) which Micro Four Thirds users find impossible to achieve with AF lenses even with the new expensive and awesome Olympus mZD 25mm f/1.2 lens – as this lens gives depth of field similar to a 50mm f/2.4 lens on a 35mm film camera, but it does so far better than any legacy lens could ever do, it is so well engineered optically.

Should you buy the new Olympus mZD 25mm f/1.2 lens?

In short, if you use Micro Four Thirds, have the money and the use for it then by all means BUY it – it is such a brilliant weathersealed fast, silent, fast and accurate AF lens and will give beautiful portraits especially of kids and environmental portraits, scenery, strong backlit performance, great low light performance and seems great for some astrophotography with its f/1.2 aperture and almost zero aberrations!

Note for some reason, Olympus Australia, is selling it at $A1899 which is substantially higher than the $US1199 RRP even taking into account the exchange rate.

BUT, if you are just searching for shallow depth of field at around this field of view and image quality is not a high priority – are there better less expensive options?

Option 1: buy a film SLR and 50mm f/1.4 lens

  • this will be cheap – get a second hand kit for around $200-$300 camera and lens
  • it will give you 1.5 stops shallower depth of field
  • BUT you will have to deal with film, you will get far less image quality – optically as well as the sensor vs film issues, you will not get image stabilisation, nor the many features of digital such as face detection AF, incredibly fast and accurate AF, etc.

Option 2: buy a 2012 model full frame digital camera preferably under $A2000 to use specifically for this purpose

Examples:

  • Sony RX1 fixed lens camera
    • the original version released in 2012 now sells at $A2700 and doesn’t have IS or an EVF, and you can’t change lenses and its fixed lens is a 35mm f/2 lens BUT it does have a leaf shutter with flash sync to 1/2000th sec so this may make outdoor fill in flash or flash to overpower the sun so much easier, but it won’t give shallower DOF as it is a substantially wider field of view lens.
  • Sony a7 Mark II mirrorless with 50mm lens
    • 2014 model 24mp full frame mirrorless with image stabilisation and hybrid AF, 1/8000th sec shutter, flash sync 1/250th sec will cost you $A2000 then you need to add in a 50mm lens such as entry level budget Sony FE 50mm f/1.8 for $A440 or the superb Sony FE Carl Zeiss 55mm f/1.8 lens at $A1200
  • Canon 6D with a 50mm lens
    • the 2012 entry level Canon 20mp full frame dSLR can be bought now at $A1800 then you just need to choose which 50mm lens to buy of which there are many and you can even pay around $A1900 for the Canon EF 50mm f/1.2 but it is not a great lens optically wide open
    • this will give you around 1 stop better high ISO than the Olympus, radio TTL remote flash and shallower DOF BUT you lose out on image stabilisation, edge-to-edge sharpness, the wonderful optical capabilities of the Olympus lens, the fast, accurate AF and the eye detection AF, far better weathersealing,  faster flash sync, far greater spread of AF points, faster burst rate, etc which comes with the Olympus cameras, and even with the Canon lenses used at f/2.4 for same DOF, the Olympus will still give better edge-to-edge image quality at ISO 200 which you are most likely be shooting at unless it is very low light such as astrophotography, so the noise difference is inconsequential.

Option 3: Buy an AF 25mm f/1.4 lens instead:

  • OK you are not going to get quite as shallow a DOF as the Olympus 25mm f/1.2 lens and it won’t be as good optically, and certainly won’t be as fast to focus, but if you can live with these, the money saved may be worth it, or it could be false economy
  • The original Panasonic Leica-D 25mm f/1.4 in Four Thirds mount initially cost as much as the Olympus lens, but second hand the price should be lower – a great lens, but heavy, AF is much noisier and slower, even though it is CDAF compatible, AF is often a stuttering experience
  • The Micro Four Thirds version – the Panasonic Leica-DG 25mm f/1.4 lens but optically not as good and operation is noiser and AF not as fast.

Option 4: Buy a really fast 25mm f/0.95 manual focus lens:

  • this will give you full frame level of shallow depth of field, but also full frame level of soft, ghostly imagery wide open and you will need to shoot in manual focus

In the end, you will have to decide which compromise you prefer.

As you can see, every option is a compromise – and that should not surprise any photographer as usually every camera-lens combination does have a compromise – you have to decide which compromise you will accept.

In this case, forego a touch of shallow depth of field and money for an awesome lens, or go for more shallow depth of field but worse overall image quality, or decide against shooting shallow depth of field at the focal length and stick with your f/2.8 zoom lens or perhaps the Panasonic 20mm f/1.7 pancake lens or, perhaps resort to the 45mm f/1.8 and 75mm f/1.8 which make more shallow DOF shots with less busy, more compressed backgrounds.