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(September 2024)
Introduction While the R5 is still an excellent camera for most purposes, over the four years that I have had it, I became aware of the R5's limitations for fast action photos of wildlife (mainly birds and dragonflies). My niggles were mainly the following:
So for the last year or two, I eagerly followed the rumours on the R5's successor and its likely specs. When these rumours turned to something more concrete I resolved to purchase the R5 Mk II as it seemed to address all the above limitations of the R5. So I ordered it as fast as I could when the pre-order link became available in July 2024! Even so I wasn't fast enough to get one of the very first batch to arrive. But unlike in 2020, I didn't have to wait long (only a few days) before I was informed mine was in stock and would be delivered the next day! There are now stacks of YouTube videos and the like on the R5 Mk II, which go into all aspects of this new camera. I generally agree with them, and see no point in covering the same ground here. Instead I'll give a few brief comments about how I am finding the new features available and some examples of images I've been able to obtain in the few weeks since it arrived. Initial impressions When it came to setting up the buttons and dials, I generally followed the excellent YouTube videos by Jan Wegener and Wild Alaska. As per all the YouTube reviews and the camera specifications, the R5 Mk II addresses all three of my R5 limitations given above.The main benefits I have seen so far include:
Of all the new features of the R5 Mk II, I think pre-capture probably has the greatest potential for getting photos that simply weren't possible previously with the R5. The R7 also has pre-capture but its implementation is poor in two main respects. Firstly all the images in a burst go into a single CR3 file. The individual frames need then to be extracted either on-camera or using Canon's DPP4 software. Secondly, after taking the sequence, the R7 locks-up and won't take any more shots until the buffer has cleared completely. Also of course with the R7's pronounced rolling shutter effects (far worse than with the R5), any action shots in the pre-capture sequence are likely to have wings or other fast moving parts noticeably distorted. Happily with the R5 Mk II, neither of these issues are a problem. All the pre-capture images are written simply as normal CR3 files, like any other. Also there is no need to clear the buffer so that another sequence can be started while the previous one is still being written to the memory card. This is so easy to use that some photographers seem to leave pre-capture on the whole time. The only penalty is that a very large of files are collected, as every pre-capture sequence includes up to 15 images prior to the shutter press. Large, fast memory cards are needed! Some have complained that the time data collection starts, prior to the shutter press is fixed at 0.5 seconds (i.e. 15 frames at the max 30 fps). This maybe a little nitpicking and will hopefully be addressed in a future firmware update (or knowing Canon, maybe not!). I have been playing with this new feature for diving/flight photos of a Kingfisher, and once I got the hang of it, I am pleased to say it is working very well. This flight shot below was taken well before I reacted to fully press the shutter button, and hence I wouldn't have got it without pre-capture.
Reduced Rolling Shutter effects At the heart of the R5 Mk II is a 45Mp sensor which is stacked and back-side illuminated (BSI). The read-out time is said to be 6.3ms, which is much shorter than the R5 (c. 16 ms) but appreciably longer than the Sony A1 and the Nikon Z8/Z9 (very similar sensors in all 3 of these cameras) which is said to be < 4ms. However, all the reviews I have seen so far have said that rolling shutter effects are virtually absent from the R5 Mk II. In my more limited experience to date, I haven't noticed them either except for dragonflies in flight which are very challenging due to the high speeds of their wings. For more on this, see below. I am very pleased to find that the image warping and wobbling on the hand-held R5 has vanished. This has made capturing the images needed for focus stacking much easier, with fewer corrections needed in post-processing. The focus stacked image below definitely benefitted from the hugely improved image stability when the camera is hand held.
Another possible benefit of reduced rolling shutter effects would be to use the electronic shutter for dragonfly in flight shots (previously with the R5, I always used the mechanical shutter as I was sure the rolling shutter would cause distortion of their rapidly moving wings). This is clearly a challenging task for a stacked sensor and the electronic shutter, as dragonfly wings move so fast - probably faster than hummingbird wings? The Southern Hawker flight shot below came from a very brief burst of R5 Mk II shots with the electronic shutter and the 30 fps greatly increased the chances of getting a sharp image with the wings in a favourable position. The improved AF almost certainly helped as well, as this individual wasn't being very co-operative and this image was one of the only burst I managed to get before the sun sank into cloud and all dragonfly activity came to a grinding halt! Although the wings on this shot look OK, on close examination, further images taken in another more recent session are still showing some strange effects in the wings, which I think are most likely to be due to residual rolling shutter effects. Hence my current conclusion is that dragonflies in flight are too challenging for the electronic shutter on the R5 Mk II, and that it would be better to revert to the 12 fps mechanical shutter. However even mechanical shutters do not act instantaneously and presumably can show rolling shutter effects for very fast movements. A typical time for a mechanical shutter to cover the whole sensor is said to be c. 4 ms, which is not that much less than the 6.3 ms for the R5 Mk II. Yet with a mechanical shutter I have never noticed anything that looks like rolling shutter effects on dragonfly wings when in flight. So a bit of a mystery in my mind at present. Perhaps things will become clearer in the 2025 dragonfly season!
Image Noise compared with other cameras Following my previous work, over many years, on this topic (see here), I was very interested to see how the noise performance of the R5 Mk II compared with the original R5. A beta version of RAWDIGGER iquickly became available to support the R5 Mk II, so I was able to repeat my analysis procedure to measure quantitatively the image sensor noise prior to de-mosaicing and any raw conversion (i.e. before Photoshop, DPP or any other raw converter gets to work on the image). For more info on this method, go to this page. In the plot below, taken from this page, I show the 18% signal-to-noise ratio (SNR) values (which correspond to the noise levels in the mid-grey image areas) for the R5 Mk II when using the mechanical and electronic shutters, compared with the R3, the original R5, the R7 and various older Canon DSLR cameras. Also shown are the corresponding DXOMARK "screen" 18% SNR values, adjusted by a constant value (about + 5dB) to remove the systematic difference from my values. For more on this, see here.
The simple conclusion from the results above at ISO 1600 is that with the R5 Mk II, both the mechanical and electronic shutters give very similar values to that obtained with the original R5 (for which the mechanical and electronic shutters give very similar results). Hence the new stacked and backside illuminated (BSI) sensor in the Canon R5 Mk II gives a noise performance indistinguishable from the original R5. Also of note is that use of the electronic shutter does not increase the noise compared with the mechanical shutter for the R5 Mk II at ISO 1600. High ISO Noise compared with R5 It seems that there has been much discussion online about the high ISO noise performance of the R5 Mk II, with claims that the R5 Mk II is significantly worse than the original R5 at ISO values around 12,800 and 25,600. However these suggestions appear mainly to be based on subjective assessments of various different images obtained at different times with the two cameras. The chart above, based on quantitative measurements of a standarised test chart. shows no evidence for poorer SNR in the R5 Mk II compared with the R5, but is based on measurements at the relatively low ISO of 1600. Hence I have made quantitative measurements of signal-to-noise ratio (SNR) for higher ISO values up to 25,600 to try to find this reported large reduction in the R5 Mk II's performance. My high ISO measurements are shown in the chart below which gives two sets of SNR values. The first is for the SNR of the images for mid-grey (18%). I also show values for 5% SNR which correspond to the dark grey/black areas in the images.
The chart above shows no evidence for a major reduction in noise performance for the R5 Mk II at high ISO. There is however a small effect for the electronic shutter images from the R5 Mk II which are slightly noisier than those for the R5. This effect is larger in the darker areas of the image but even then the 5% SNR value for the R5 Mk II is only about 0.8 db (or a quarter of one stop) lower than for the R5. Hence these quantitative measurements of the raw sensor data from the R5 Mk II and the R5 show very similar noise levels all the way up to ISO 25,600. So the reason for the reports of noisier high ISO images from the R5 Mk II are unclear. It is however possible that the raw converters (e.g. ACR, DPP etc) which are inevitably needed to view the images are in some way responsible for these reported differences between the R5 Mk II and the R5. |
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