2013-03-05

The Full-Frame Advantage


Once the preserve of the professional or deep-pocketed amateur, full-frame DSLRs are becoming far more affordable. The EOS 6D is an enthusiast level full-frame camera with a far lower price-point than we've seen previously from Canon, whilst the D600 is Nikon’s first consumer level full-frame model. With price tags around the £1500 mark neither could be regarded as inexpensive, but when you consider that prior to their arrival, you needed to spend in excess of £2000 to gain entry to the exclusive full-frame club, they represent exceptional value. In this blog, we’ll take a look at the benefits of full-frame cameras and how they compare to the smaller sensors used in consumer DSLRs.



What is Full-Frame?
Most consumer grade models, and a small number of pro bodies, use APS-C sized image sensors. They’re so called because they measure around 25 x 17mm, close to the size of the Classic frame size of Advanced Photographic System film.

A full-frame sensor is larger. Measuring 36 x 24mm, it’s the same size a frame of 35mm film, and offers double the surface area of an APS-C sensor. Historically, this larger size yielded a number of significant benefits. The larger sensor could incorporate a larger number of pixels, ideal for delivering high-resolution images, and the cameras were quickly adopted by portrait, fashion and studio photographers, who appreciated the extra detail. In addition, manufacturers realised that as well as increasing the pixel count, the individual photosites on the sensor could be made larger, offering better light gathering capability and capturing images with lower noise levels than their APS-C counterparts.

Depth of Field
Probably the biggest advantage of full-frame cameras is that they allow a shallower depth of field than APS-C cameras. It’s a key requirement for portrait and wedding photographers who look to control depth of field to blur backgrounds and isolate subjects from their surroundings. Whilst the smaller sensors can produce similar results, the effect is far more pronounced on a full-frame sensor. Naturally, it will take a while for new full-frame camera owners to familiarise themselves with the difference, but in a very short time will allow them far more creative freedom than they will have experienced previously.

Bigger, Brighter View
In addition, there’s nothing quite like the view of the world that’s offered by a full-frame camera. Looking through the viewfinder is amazing, the image is typically far bigger and brighter, offering you a clearer view of your subject and enables more precise manual focusing.

Wide Angle Advantage
Full-frame and APS-C size comparison
The final advantage of a full-frame camera is that lenses behave exactly as intended, with wide angle lenses retaining their wide angle perspective, ideal for dramatic landscapes. Since APS-C sensors are smaller, they give a telephoto effect to any lens that is mounted, extending the focal length by 1.5x for Nikon or 1.6x for Canon. This is great news for wildlife and sports enthusiasts, as their 200mm lens will give the same angle of view as a more expensive 300mm lens, but sadly their 24mm wide-angle lens will act like a 36mm, which eliminates any wide-angle effect.

The image above right was shot with a full-frame camera. The yellow outline shows the 1.5x crop for a Nikon DX body, the red line shows the 1.6x crop for a Canon APS-C body. Nikon uses the terms FX and DX to distinguish between their full-frame and APS-C models.

These shots were taken with the same lens on
both an APS-C body (left) and a full-frame camera (right)
The images on the left show the same shot taken with the same lens using a full-frame and an APC-S size sensor. We've made both images the same size for clarity, you can clearly see the telephoto effect of the APS-C sensor and the wider-angle image afforded by the full-frame sensor.

The Importance of Lenses
Whilst we've spoken at length of the benefits of full-frame, you could be forgiven for thinking there were no disadvantages to full-frame ownership. For the most part, that’s true, but there are a couple of considerations to make before you switch.

Firstly, the full frame sensor's ability to capture incredible detail is one of the key reasons to buy one in the first place, but at the same time it will also highlight any flaws in your lenses. The best sensors are deserving of the very best lenses, and you should consider investing in a professional level lens to bring the best out of your camera.

Besides wanting to improve the quality of your lenses, you may find that some of your existing collection simply will not fit onto your new full-frame body. Canon’s EF-S lenses, for example, have a short-back design, which enables them to sit closer to the APC-S sensor. If they were mounted on a full-frame body, the larger sensor means that the mirror would strike the back of the lens as at flipped up, so Canon utilise a dedicated EF-S mount so that the lenses can’t physically be mounted on a full-frame body.

The sensor size and image circle of both an
APS-C and full-frame camera
Even if they could, you’d still face the challenge that their smaller image circle won’t cover the larger full-frame sensor. Nikon’s full-frame bodies, on the other hand, will allow DX lenses - designed for their APS-C DX bodies, to be mounted, but automatically switch to crop mode, which restricts the sensor to a DX-sized rectangle in the middle, which means you don’t get the benefit of the sensor’s full resolution. For example, the 36 megapixel D800 produces images of 15.3 megapixels and the 16 megapixel D600 drops to 6.8 megapixels, so using your DX lenses is not a long-term solution.

The illustration on the right shows a comparison of both APS-C and Full-frame sensor sizes, together with their respective image circles - the diameter the lens needs to be in order to fill the frame of each sensor.

The distinctive red stripe of a
Canon L Series lens
One recommendation would be that if you’re considering a move to a full-frame camera in the future, you could start investing in full-frame lenses now because they’ll work with your APS-C body in the meantime. Apart from sacrificing any wide-angle capability that we mentioned earlier, you can only benefit. In the case of Canon, you’ll get access to their very best lenses too. Their flagship L series lenses that bear the tell-tale red stripe use only the very best components and construction, and Canon has never made an L series lens for APS-C bodies.

Go Large
We've talked at length about the advantages of full-frame cameras, but there’s no substitute for seeing for yourself. With a growing range of full-frame models, including Canon and Nikon’s flagship models, the EOS-1D X and the D4 (with its brilliant trade-in offer still running), there’s never been a better choice or at such accessible pricepoints. Why not pop in to our showroom in West Sussex to experience full-frame for yourself?
Nikon's flagship model - the full-frame D4













Jon Penney
Park Cameras

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