Thursday 7 July 2016

Comparing Formats, Full Frame, APSC and M4/3 Part 1 of 4


The full frame format is ideal for portraits and weddings.


It's the perennial question of the digital photography age, what format is best.  Wars on DP Review have been waged upon the question, it has fed hordes of internet trolls and probably resulted in more than a few unwise purchases and wrong turns. 

I thought that it might be helpful to put together a little summary of the the ins and outs of the various formats as it would be a great resource for my classes, but it may well prove helpful to some questioning souls in interweb land as well, hence the posts.

I have attempted to be as thorough as possible, no doubt I will miss a few aspects/benefits/issues along the way, don’t hesitate to let me know if you think something needs to be added.

Rest assured I'm not pushing any barrow in particular and I have no vested interest in getting folk to choose one option over another, for my own part I have cameras and lenses in all three formats, they all make sense to me commercially and creatively.

In this first instalment we will examine the full frame format, next time it'll be APSC and then M4/3.  Finally just for fun I will be putting forward my idea on what the ideal format could be if camera makers decided to start with a clean slate. Yes, the astute amongst you may note I have not included the 1'' format, I probably should do so but sadly it appears the mirrorless 1" format is doomed to obscurity and will in future only be populated by advanced fixed lens compacts (which are great) that lie outside the brief of this series of documents.  I have not dealt with medium format either, the market is too small and highly targeted and expensive to be of interest to the average photographer.

I want to make one thing very clear up front, in this format expose’ I am not referring to DSLRs, only Mirrorless cameras, there are three core reasons for that decision. 

One Mirrorless is the only camera type with representation across all three formats, (now 5) subsequently we are comparing apples to apples.

Two, as far as I am concerned DSLRs are a dead end technology and since this series of articles is meant to be of help to future purchasers I would rather look to the future technologically. 

Three, DSLRs lack EVFs and frankly I cannot see the sense in 2016 of even contemplating a camera without an EVF, an OVF just cripples the cameras potential, except for a small section of the photographers who mainly shoot action/sport. (you can read my article on EVFs vas OVFs here)


Basic Spec.   The image area of full frame is 36mm x 24mm, approximately 860mm square.

For the purposes of the exercise we will only compare the high resolution version of mirrorless full frame, currently that would be the Sony 42mp A7R mk 2.  I feel strongly that unless you are prepared to go with the higher resolution options most of the benefits of full frame become null and void, only a high res sensor will provide all the benefits and flexibility the format has to offer.


Cost

No getting around this, the most basic full frame camera is vastly more expensive than the cheapest APSC or Mirrorless versions but importantly as said, if your going full frame then you really should be going for the "hi res" version and that is going to drag $3000.00 plus from your credit card before you get started on lenses. A top drawer 24mp APSC or 16mp M4/3 will be less than half that amount.  Sure money isn’t everything to every photographer but its not irrelevant either!


Performance

Image quality is truly superb, no question, but some smaller sensor models offer results which under most normal circumstances are just as useful and look just as good but in ultimate terms full frame takes the trophy.

Dynamic range of the latest full frame models is clearly superior to the best M4/3 cameras but the best APSC sensors are now very close if not as good, which is not surprising as the individual pixels are pretty similar in size between APSC and hi res Full Frame.

Tonality can and often does have a nicer quality than smaller sensor cameras, this is however probably due more to the higher resolution than any special advantage at the pixel level as again the pixels in all 3 formats are very similar in size.

Highlight rendition can and often is better with Full Frame as the overall exposures can be better held back without incurring a significant shadow noise penalty. However much of this is due to the current high end FF sensors simply being the current state of the art, again the very best APSC sensors are now tantalisingly close.

Full Frame camera models are currently more likely to offer 14 bit, many smaller formats are still working in 12 bit RAW, this can offer benefits when the file needs to be heavily pushed in the RAW processor, making banding a shadow degradation less of an issue.

For long distance landscape work the Full Frame sensor reigns supreme as adequate DOF is rarely an issue and in the main the images are more likely to be shot on a tripod, but of course there is a significant weight penalty involved in transporting the gear to the shooting location if one has to hike it.

Depth of field is potentially very shallow, this is blessing for portraits and many other shooting styles where one requires differential focus but it's also a curse for many types of images such as landscapes and macro where extended DOF is generally needed.


Flexible format options:  

A 42 mp full frame sensor can be cropped to provide the equivalents options from the other formats:

APSC @ 18.6 mp (approximately, could be a little less or more depending on what version of ASPSC you are referring to)

M 4/3  10.9 mp

Additionally 42mp full frame can be cropped to a very nice 24mp square

It’s fair to say that Full Frame is the ultimate format for flexibility in cropping to smaller format sizes.

However it's not all positive for the full frame user, the extra megapixels are often not needed at all for many shots and the RAW file sizes are always larger, which is a waste if you intend to crop most of the frame away or simply use the files for Facebook and online sharing. Having the option to save smaller RAW files would be helpful but currently that option has not migrated to the FF mirrorless world.


Aspect Ratio

Full Frame is easy to crop to any aspect ratio you may desire, however it’s also true that a good many photographers feel that a 4:3 aspect ratio would be a better starting point, there is nothing sacrosanct about the 3:2 ratio, it is a legacy of the first Leica which was actually designed to shoot stills on movie film for the purposes of checking setups/lighting etc.

A 4:3 aspect ratio would actually be a closer match to the print sizes that most people tend to produce when making enlargements, for example 10 by 8s, 5 by 7s, 11 by 14s etc.


Weight

Full frame mirrorless cameras are not that much heavier than APSC and M 4/3 versions for example:

Sony A7R mk 2  640g

Fuji X- T1   440g

Olympus EM 5 mk 2  463g

Of course there are some much lighter M4/3 bodies on offer but I am trying to keep things on an even keel by comparing cameras of similar quality, functionality and target audience.

Sony’s A7 series is probably about as small as can be done for the full frame format, M4/3 and APSC models can be far smaller if people willing to sacrifice knobs/buttons and grips, e.g. NEX 5n, Panasonic GM1 etc.


Practicalities

IBIS (in body image stabilisation) works well but not as well as it does on M4/3  bodies due to physical constraints of moving a much larger sensor.

Macro photography can be far more challenging and complex due to depth of field limitations, but you can always step back a bit and shoot in a smaller format version if you wish.

Generally apertures need to be stopped down more to get adequate DOF or optimal lens performance so practical shutter speeds tend to be slower, in some instances such as shooting sport this is circumvented by high quality wide aperture lenses that offer peak performance very close to maximum aperture, the lens cost is vastly higher course and they are far heavier than most photographers would like.

Much shallow DOF stuff done on full frame cameras lacks adequate sharpness for medium to large prints, it looks OK on the web but doesn’t translate well to print. In truth few working professionals would risk the lottery of shooting a paying job at f1.4, generally f2.8 is a wide as they go! This to some degree negates some of the assumed advantage of FF when it comes to shallow DOF options.

The EVFs and LCDs used on FF cameras are no bigger or better specced (one Leica model being an exception) than the options on smaller formats so there are no gains in terms of  shooting convenience.

If you want to shoot Panoramas it requires a bigger more cumbersome rig and a heavier tripod.

Focus absolutely needs to be spot on, it will not be fudged by DOF masking effects, it is very easy to see with a 42 megapixel file if the focus is just a little off once you zoom in!

FF lenses are often not very fast to focus as many are old designs that have simply been warmed over to bring them up to date but the newer versions are often excellent.  On the issue of focus a great many of the best FF fixed focal length lenses are not even auto focus.

Shutter shock is potentially greater making it more likely you will need to use the electronic shutter option more often.  Generally the mechanical shutter is louder as well. It should be noted however that some M4/3 models have shutter shock issues in certain speed ranges and need to by used in the electronic shutter mode to ensure good results consistently.

Heavier gear does make using full frame more physically taxing on a long handheld shoot. (especially with pro grade cameras and lenses)

You are far more likely to need a tripod to support your camera using telephoto or over standard focal length lenses or under low light, especially compared to M4/3 setups that having very effective 5 axis stabilisation.

Shooting 4K video means there is a greater danger of the sensor running hot, at least in the current compact mirrorless bodies, this can limit the run time, no doubt future models will address this problem, but currently only M4/3 models seem to have eradicated the overheating issue for 4K shooting.

For the photographer wanting one tool than can do almost everything a compact mirrorless FF camera, with high res sensor is probably the ultimate option…but at present that means there is only one choice the Sony A7R mk 2, the lower res versions do not offer the same downsizing flexibility and offer little if any real advantage in dynamic range or high ISO performance.  The A7S is somewhat better at very high ISOs but really needs to be shot only as a full frame camera as the resolution is only 12mp to start with.

Automated image stacking is not currently an option with full frame and will likely prove hard to implement due to the larger sensor size and the difficulty of very rapidly moving (refocusing) much larger and heavier lens elements.


Lens Size and Weight

No getting around the physics, full frame lenses are considerably heavier and larger, assuming you want to maintain a high level of performance, with the exception of Leica lenses there are no high performance full frame lenses that could be described as anything like petite, the only option available to make them smaller/lighter is to reduce the maximum aperture, which is fine but not the path most high end lenses have taken.

Long focal length lenses, i.e. those over 200mm become very heavy and large if you wish to maintain a reasonably wide aperture, this makes them much more onerous to cart around and far harder to use hand held.

Despite the bragging one see on the internet in relation to fast full frame lenses, really fast lenses with apertures such as f1, 1.4 and 1.2 are hideously expensive and don’t perform close to well at wide open, (with a few very notable but expensive exceptions such as the Ziess Otus) therefor for most practical purposes lenses end up being used at f2.8 or smaller anyway, unless of course you really are going for that soft bokeh monster look.


Lens Performance

It is far harder to achieve high and even cross frame quality with full frame sensors without adding extra complexity and ultimately extra cost, and even allowing for that many expensive full frame lenses still exhibit poor corner performance and vignetting unless well stopped down to f5.6 or sometimes smaller.

Long fast telephotos give a very unique look where the image rapidly transitions from in focus to out of focus, this is not easily replicated in smaller formats.


Lens Options

There is a wealth of cheap film era lenses to use, many of which are still very good, but most film era zooms don’t perform at all well on full frame digital cameras, the fixed focal length options can be excellent however.

Many people crave to use Leica lenses of FF mirrorless, sadly though some work very well indeed many of the wider angle options are not so great and give a very poor cost to performance ratio.

Very wide angle lens options are plentiful, including shift lenses which do not offer any where near the same flexibility on smaller formats.

There are no pancake zoom options if you want to cover the full frame, the only truly pancake lens options are fixed focal length and generally these are very average performers.

So there you go, as I said I am sure I have missed a few things but hopefully the info is food for thought, stay tuned for the APSC analysis.






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