Canon Powershot SX70 How to get the best pictures 27 March 2019

The SX70 is the latest and best  model in Canon’s Powershot  SX(2 digit) series of compact bridge style superzoom cameras.

Canon has a long history of making this type of digital camera for the consumer market starting with the S1 of 2004. Since then  Canon has changed their naming scheme somewhat but in recent years the SX(3 digit) models have lacked an EVF while the SX(2 digit) models have a built in EVF and fully articulated rear screen.

My first acquaintance with the SX(2 digit) series was the SX20 in 2009.   It was a decently good camera for its time with a good level of specification compared to its peers. I remember that it had a very smooth, slippery handle and produced large amounts of chromatic aberration which, by the way is still a weakness of Canon’s compacts.

The SX50 of 2012 became a firm favourite among SX aficionados for its good quality lens and overall good picture quality.

Then in 2014 came the SX60. Great was the disappointment on Canon user forums from the many faithful who found the SX60 a backwards step in image quality and user experience.

For some reason which I now forget I bought an SX60 and was disappointed along with all the others. I just could not get decently sharp pictures out of that camera no matter what strategy I tried at the point of capture or in post processing. It had a nice handle though…………..

In September 2018 Canon announced the SX70 with the same body and lens as the SX60 and even more pixels jammed onto the tiny 7.7mm diagonal sensor.

This did not look promising. 

The major review sites such as Digital Photography Review, Imaging Resource and Camera Labs did not post full reviews. This is usually a sign that there is, or is perceived to be a problem with the camera. Rather than post a bad review these sites simply pass onto the next big thing which at the time the SX70 was released was a bunch of all-new  mirrorless full frame bodies and lenses.

The usual suspects including Photography Blog, Tech Radar and e-Photozine posted their quick so-called “reviews” soon after the camera was released. Unfortunately I have learned that these sites provide little more than a re-wording of the published specs together with a few snippets of often incorrect commentary.

So no help there.

But here is the thing. I find this camera type very appealing. In one compact relatively inexpensive package you get just about everything. Wide angle, super telephoto, nice handling, EVF, flippy screen, close-ups, video ….and so on.

If some manufacturer could get the performance and output right I would be a happy camera user.

So I bought an SX70 to test it myself.

And….it’s not bad. Not bad at all. Verging on quite good in fact although with some important caveats which are the reason for this post and which I will discuss below.

Although Canon made no statement that I ever saw about improvements to the lens, AF or IS I found in fact that all three of these key ingredients are in fact considerably improved in the SX70.

In addition they changed the D-Pad from the old flat-with-5-buttons type to the much more usable rocking saucer type.

There also appear to be numerous improvements to speed and efficiency of operation.

All this adds up to a camera which looks the same and has most of the headline specs as the SX60 but which is in fact a much better camera. It routinely makes better pictures and is nicer to use.

Now let’s get to those caveats.

There are in essence two.

1. The minor one is a somewhat less than wonderful user experience, particularly for the enthusiast who wants to get the camera off  Auto Mode and take control of proceedings.  The point of my discourse is that in order to get the best from this camera the user must get off that Auto setting.  

Why ?

2.  The reason is the second and major caveat which is luminance noise which is present in objectionable levels in the SX70 even at base ISO.

How bad is the noise ?

While testing the SX70 I had available a Lumix FZ80, an 18Mpx  budget consumer superzoom with components mostly carried over from the 2013  FZ70. The FZ80 is certainly no star in the image noise department.

On my tests at matched output size, the  SX70 has about one EV step more noise at ISO 400 than the FZ80.

I also tested the SX70 against my Lumix G85 M43 camera and found that ISO 200 on the SX70 has about as much luminance noise as ISO 3200 on the G85.

This is a very poor noise performance the like of which I have not seen since the Powershot G10 of 2008.  I owned one of these for a while. It had a nice sharp lens but image quality fell apart at ISO 400 with excessive luminance noise.

So the main consideration in getting best results from the SX70 is to develop strategies for managing that noise.

These strategies involve every aspect of the imaging process from subject selection and lighting through camera handling and exposure management to post processing RAW files and final output size.

So with those considerations in mind here are my suggestions for getting the best possible photo output from the SX70.

Only you can decide whether the effort is worthwhile.

You might think that with a 20Mpx sensor the SX70 would handle detailed subjects well. In practice however the camera is better suited to subjects which are not dominated by fine detail.  There are two reasons for this

1. In the image processing pipeline you have to deal with the noise which appears as strong grain. This involves noise reduction strategies which always reduce the amount of detail available.

2. The lens does a pretty good job for a budget 65x zoom but let’s be realistic. Outside broadcast TV lenses with this kind of zoom range cost hundreds of thousands of dollars.

I paid AUD729 for the entire SX70 including the lens. You don’t gots ultimate resolution here.

The only way to fit a 65x zoom lens into such a compact package is to

a) use the very small smart phone size (7.7mm diagonal) sensor and

b) restrict the lens to small apertures (relatively high f-stop numbers)  throughout the zoom range. 

So we have a small sensor with a low signal-to-noise ratio which means the sensor needs plenty of light,

but a lens which is not letting much light through to the sensor.

Solution ?  Take pictures where and when there is plenty of light. For this camera brighter is better.

This does not mean the camera is impossible to use indoors or in low light but doing so does require careful techniques for exposure management and post processing. See below.

1. Always use RAW output. JPGs apply massive amounts of noise reduction which is not adjustable. This gets rid of the noise and most of the detail as well even in bright light outdoors.

2. Use P Mode. This will ensure your aperture is the widest possible at every focal length. The best aperture is the widest available (smallest f-stop).

Alternatively set Av and f3.4 at the widest end of the zoom. The f-stop will increase as the lens zooms out and decrease as you zoom back, always staying at the lowest available for each focal length.

3. Set Auto ISO upper limit at 200. Yes, 200. That will give you luminance noise levels equivalent to ISO 6400 on Micro Four Thirds or 25,600 on full Frame.

4. Use the flash indoors. Set flash to -1 stop.

5. View through the EVF when possible. It is easier to hold the camera steady this way.

6. Monitor your shutter speed. Practice shooting at very slow shutter speeds. The IS helps a lot with this.

This is a fairly arcane topic with each PP enthusiast having their own special combination of magic moves.

I use Bridge, Adobe Camera Raw and Photoshop.  People wax lyrical about other image editing programs but I notice the one being praised changes quite often. Many experienced photographers find they get best results when they stick to Photoshop and learn how to use it properly.

With the SX70 I find I have to apply a lot of sharpening and a lot of noise reduction, both at the same time. Experience and experiment are required for the best results.

Overall a much higher level of intervention is required than would be appropriate for output from larger sensors.

In the Lens Corrections Tab of Camera Raw, I go to the Profile and Manual tabs to remove purple fringing.

In the Detail Tab:

Sharpening varies from around 60 in the middle of the zoom range to 100 at the long end.

Radius varies from about 1.5 at the wide end and middle of the zoom range to 3 at the long end.

Noise reduction is required even at ISO 100 and varies from 30 to around 60.

Sharpening amount and noise reduction have to be balanced against each other while viewing the image on screen to find the most appealing result.

Tip:  Periodically view at 50% on screen. You will find that noise which seemed objectionable at 100% is no longer apparent at 50%.

Tip:  Never try to remove all the noise. If you do you will just end up with the melted-plastic-smashed-avocado look of the JPGs.

Tip:  Think about how you want to share or display each image. If the final output size is small then files which looked extremely grainy at 100% can look just fine.

The paradox of the SX70 and most other small sensor superzoom cameras is that the people most likely to use them (casual snapshooters who set the Mode Dial on Auto and leave it there) are least likely to get best possible results from the cameras.

On the other hand the enthusiast/expert types who could get the best results from these small sensor models are more likely to choose something with a larger sensor.

Such is life.