A Beginner’s Dilemma – Canon SL1 vs. Sony RX 100

by Bill Van Antwerp, President LACUPS
A couple of weeks ago someone suggested that the Sony RX100 generated far nicer photos than the Canon SL1. Having shot both of them on land, I was not convinced. However underwater it might be a different story. So thanks to Andy Sallmon our local Sea and Sea representative, I got the chance to take both diving near Catalina Island. The Canon SL1 is a digital SLR and the Sony RX100-II is a point and shoot with a similarly-sized sensor.

A comparison of the two cameras is shown below:

	Sony RX100-II	Canon SL1
Sensor	5472 x 3648 (20 MP)	5184 x 3456 (18 MP)
Format Still	JPEG, Raw	JPEG, Raw
Movie	MP4, MPEG, H.264	MOV, MPEG-4, H.264
Memory Card	SD, Sony Memory Stick Duo	SD
Image Stabilization	Optical	Lens Dependent
Dimensions	4.0 x 2.3 x 1.5	4.6 x 3.6 x 2.7
Weight	281 g	370 grams
Lens (as shot)	Zeiss 28-100 (35 mm equivalent)	Canon 60 macro
Sync speed	1/1000	1/250
Shutter Lag	372 ms (with flash)	102 ms (with flash)
Viewfinder	Electronic	Optical
Smallest Picture Size	76 x 51 mm	23 x 15 mm
Price	$648.99	$649 (with 18-55)

The Canon SL-1 was set up with the Canon 60 mm macro lens and the RX100II of course had only its beautiful Zeiss lens with no wet diopters. I know this is an unfair comparison of the two systems, but that is what I had and that is what I shot.

Sea & Sea housings were used for both; the MDX-RX100/II and the RDX-100D. These were paired with twin Sea & Sea YS-D1 strobes, shot in TTL mode with RAW photo capture mode.

Now, I am a dedicated macro guy, I love to shoot little stuff, particularly nudibranchs, but on this day at least, there were no nudis to be found on the front side of Catalina. There were however a bunch of garibaldi around including some juveniles and for little stuff comparison, there were a bunch of blue-banded gobies. 

For comparison purposes all files were opened in Lightroom (5.6) with the punch preset of Clarity +30 and Vibrance of +25.

The first photo is a close up of a garibaldi from the SL1.

Photo 1: Garabaldi from Canon SL1

Figure 2 is a garibaldi from the RX100. The conditions were not quite as nice but you can see that the color balance from the RX 100 is quite good.

Photo 2 from Sony RX-100II

Figure 3 is a ubiquitous blue banded goby shot with the Canon

Photo 3 from Canon SL1

Figure 4 is the same blue banded goby with the Sony. 

Photo 4 from Sony RX-100II

Figure 4 shows a lot of green algae next to the goby; this is not a flaw of the camera but rather is the color of the reef where this was shot. The differences in the magnification are significant but that is more due to the fact that I used the Canon with the 60 macro lens.

Figure 5 is a juvenile garibaldi with the SL1

Photo 5 from Canon SL1

and figure 6 is a slightly older garibaldi shot with the RX-100II.

Photo 6 from Sony RX-100II

In the RX-100 shot, the green tint can not be easily removed and still keep the garibaldi, more or less perfectly exposed.

I also got to shoot the RX-100 in the Sea and Sea housing with the D1 strobe at an indoor pool function with beginning discover students.

Sony RX-100II

Sony RX-100II

Sony RX-100II

Conclusions: If you are starting out underwater and are looking for a first system, either of these cameras will help you get great underwater shots. The Sony is a great little camera, but occasionally in our quite green Southern California waters there was a little color-cast that was impossible to remove. Shooting the same types of scenes with the Canon (and the exact same strobes), led to more neutral colors.

The advantages of the Sony are it's small size and the ability to shoot both wide and macro on the same dive, if you have the appropriate add-on lenses.

The advantages of the Canon are that you can shoot much smaller subjects without an add-on lens in a really small, compact package.

For me as a macro/super macro photographer, the Canon is by far the preferable package. You can of course add on a wet diopter to the Sony, or even stack them, but the starting point for magnification is about 11 times less area.

At the end of the day, both cameras performed very well underwater, both housings were a joy to use, and both cameras took very nice pictures; you won’t go wrong with either choice.