Canon RF 600mm f11. A super-tele lens for the rest of us

Interesting  compositions with compressed perspective are possible with the long lens

Canon introduced their new RF mount EOS R camera in September 2018  together with some exotic glass like the 28-70mm f2 L and the 50mm F1.2 L. But Canon’s marketing people know very well that many of their customers want more budget oriented optics which still offer high optical and mechanical capability.

Two of the more interesting examples of this style of lens are the RF 600mm f11 and RF 800mm f11 super-telephoto lenses, introduced last year.

Until now, super-tele lenses have been big, heavy and veryexpensive.

* Prices as listed by a Sydney photo equipment retailer, GST included.

Static and perched birds in good light are easily captured with the RF 600mm f11

The smallest aperture at which most Canon DSLRs can autofocus is f5.6 (with the mirror down).

But the new mirrorless RF mount models use Canon’s dual pixel AF (DPAF) which can autofocus down to f22.

This has allowed Canon to produce compact, low cost super tele  lenses which would not function on a  DSLR.

Which brings us to the RF 600mm f11 IS STM.  I bought one of these and have been exploring its capabilities over the last few weeks.

The experience of using the lens has been mostly very positive and the results mostly very good to excellent.

Zoo photo in low light at ISO 20000 on the R5

In practice there are a few negatives. These are

* The small (fixed) aperture limits the lens’ usability in low light such as in a rainforest or dawn/dusk scenarios. In these situations it is necessary to use either very slow shutter speeds or very high ISO sensitivity settings or both. This impacts negatively on image quality.

There are two offsets however which improve the situation:

The stabiliser on the RF600mm is very good. I have been able to get sharp pictures with a static subject down to 1/15 second hand held.

The R5 and R6 bodies can deliver good image quality even at high ISO settings with judicious management in Photoshop.

* The minimum focus distance is 4.5 meters. I have found quite often that birds will come closer than this, which is frustrating.

* The autofocus is very good but not up to the level of consistency seen with wider aperture RF lenses. The RF 600mm does miss focus sometimes with still and moving subjects even in bright light.

* Autofocus is available only over a part of the frame indicates by a square overlaid on the viewfinder image.  

So those are the negatives.

I include a bird in flight to show that BIF is possible  but the keeper rate in my hands is very low due to the difficulty of finding the bird and keeping it in the frame with such a long lens.

The rest is all positive.

The lens is light, compact (for a super-tele) it mostly does focus quickly and accurately on still and moving subjects and it is very sharp with good contrast. It is a pleasure to use and the results are very good to excellent.

Another  composition with compressed perspective

Surfing photos are easily obtained from the beach with the 600mm lens