Wednesday, February 20, 2013

Wednesday Commentary: Should I Move To Full Frame? Part 2

In the first part of this series features and accessories associated with entry level full frame cameras, namely the Nikon D600 and Canon EOS 6D, were discussed. This second part will cover one of the, potentially, expensive aspects of moving from a crop sensor body to a full frame body, lenses. Generally speaking most of the user base that this series is covering will have a number of full frame compatible lenses already, but some shifts might be needed anyway. Like the first part of the series, the comments here are based upon the decisions I faced when switching my primary camera from a crop sensor DSLR to a full frame DSLR.

If you cannot cover all your bases with full frame lenses right away that may or may not be an problem during the transition period. Nikon users wont have an issue, since the D600 has a crop mode that supports DX lenses. The Canon EOS 6D on the other hand will only support EF lenses, which cover the full image circle. There is no crop mode on the 6D, and the mount does not accept EF-S lenses. In any case you need to ask yourself if the move to a full frame body makes sense based on the lenses that you have, and what you will need to maintain your style of photography. If you have a large set higher end crop sensor lenses (3+) then the move to full frame could be very expensive, beyond the cost of the body and accessories, discussed last week.

The largest group of people that will need to shift the lenses in their bags will be those with super wide angle lenses for crop bodies (Canon EF-S 10-20mm, Tokina 11-16mm, Nikon 10-24mm etc). Those lenses might be great wide angle lenses on crop bodies, but they do not cover the entire full frame image circle, and in some cases cannot even mount on full frame bodies. The other group of users that may need to upgrade are those with mid-range fast zooms for crop bodies (17-55mm F2.8G, 17-55mm F2.8 IS or Tamron/Sigma 17-50mm F2.8). Those lenses will no longer be useful on full frame, so purchasing a replacement mid-range zoom might be required (24-70mm F2.8).

Some users who have purchased crop sensor macro/micro lenses (Nikon 40mm F2.8G, Nikon 85mm F3.5G VR or Tamron 60mm F2.8), may also find themselves in a position to need a full frame macro. In this group, you'll want to consider a longer macro lens, or you will notice a big difference in terms of framing your subjects. On a full frame body the 60mm macro gives similar framing to the 40mm on a crop body, and a 150mm macro would give similar framing to the 85mm. This isn't about equivalent focal lengths, but rather framing at similar focusing distances. This is particular noticeable with macros, due to the distance from the subject required to achieve 1:1 detail. Full frame bodies also have some differences, like having narrower of depth of field, so for macro shooters a crop sensor body is easier to work with.

People with super telephoto lenses are the least likely group of users with the need to upgrade lenses, since almost all of them cover the full frame image circle. The only Canon and Nikon telephoto lenses that do not cover the full frame are the AF-S 55-200mm F4.5-5.6G (VR and non-VR), AF-S 55-300mm VR, and EF-S 55-250mm IS. My suspicion is that most users looking at this post wont be using such lenses though. The only downside is that you will need to be closer to your subject to achieve the same framing on a full frame body. You might find yourself wanting to trade that 300mm lens for a 400mm lens, or adding a teleconverter/extender. Due to this loss, of apparent reach, many birders or sports shooter still like to use crop sensor bodies.

Lenses are one of the greatest strengths and weaknesses of the full frame system. The vast majority of DSLR lenses available today cover the full frame frame image circle (unless they are marked DX or EF-S). The downside is the full frame lenses may weigh more than equivalent crop sensor lenses, although that is not always the case. Just as there are budget user crop sensor lenses, there are budget full frame lenses. The largest pool of lower cost full frame lenses are older models, on the used market, but some of them may struggle to take full advantage of the resolution of modern cameras.  

When you are deciding whether or not to move to a full frame camera, you need to make that choice based on more than the cost of the camera alone. One of the largest costs associated with switching to full frame from a crop sensor body is the need to get new lenses. If you have a number of higher end crop sensor (DX or EF-S) lenses, the cost of upgrading might be higher than originally anticipated. Users of all types of lenses will also have to face the reality that you need to be closer to the subject matter to achieve similar framing, with the same focal length, on a full frame body. This will be noticeable to macro and super telephoto lens users primarily. Users of wide angle lenses will need to get full frame equivalents to their super wide crop lenses, generally at twice the cost, to get one with the same maximum aperture.

Part 3: Cameras