ISO Test

Andrew Williams

By Andrew Williams



  • Recommended by TR
Canon PowerShot SX40 HS


Our Score:


ISO scene

The full ISO test scene. The cropped images below are reproduced at 100%.

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Detail starts to fall apart at ISO 800

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3200 is a smudge-fest, with little of the original detail or cuddly octopus's... fur visible.


October 31, 2011, 7:22 pm

I own a Panasonic TZ-5 and am interested as to the comparative performance of this camera against it / a DSLR.

You keep mentioning that a DSLR would offer far superior pictures, but really how superior ? I mean would anyone really notice on pictures taken in normal conditions, or would you need to zoom in to the max on the photo and know what you were looking for ?

Also would this offer better results than the my TX-5 ? And again, buy a real margin ?

Whilst I love the idea of the DSLR the sheer bulk is very prohibitive to carrying one around, especially when you then add the need to carry lenses too.

Finally how good is the 1080p video ? I know some of the DSLR's are now taking practically broadcast quality; is this on a similar level ? Is the optical stabilisation still working whilst taking video ?

Thanks for any help.

Mike B

October 31, 2011, 8:19 pm


A DSLR has a larger image sensor which enables you to get those nice background out of focus images. The downside is having to carry a larger and much heavier device. The only other option is to go for the halfway house of the mirror-less cameras such as the Panasonic micro four thirds models. But to get a reasonable zoom and video will set you back £1050 (GH2 + 14-140mm lens).

The Canon SX40 or Panasonic FZ150 will be a step up from your current camera and for most family users give the results they want in a relatively simple way. The FZ150 is a little cheaper than the canon at the moment and also a little lighter.

Look at the sample images and video clips available on many sites to see if you feel it matches your expectations.

Martin Daler

October 31, 2011, 9:37 pm

A DSLR certainly won't produce superior images unless you have it with you. And since you say that the bulk would be prohibitive, that likely means that you won't.

Even if you have a DSLR, I'm betting there is a big empty space in your camera bag where the 840mm lens isn't.

So if you need what this camera can do, and you wouldn't carry a DSLR and a rucksack full of lenses, then you have answered your own questions.


October 31, 2011, 9:46 pm

Yep, what Mike said.

Whilst a large DSLR sensor will offer better image quality, the benefits aren't solely in that area. The larger sensor on a DSLR allows for a narrower depth of field, so it's easier to attain that professional-looking defocused background, while the focus on your subject remains pin sharp.

Also, light sensitivity from a large sensor can be excellent, so images taken in low light conditions are often so detailed, you find yourself using a flash far less than you might with a compact.

Improved light sensitivity also has the effect of allowing faster shutter speeds, so it's easier to capture a fast moving subject with a larger sensor.

All of these benefits (as well as others I haven't mentioned) dramatically widen the scope for creative, artistic photography.

The downsides are bulk, expense and focal length. Bulk can be mitigated by purchasing a mirrorless camera like Sony's NEX-5N, which retains the large DSLR-like sensor in a relatively compact body. Unfortunately, large sensors also require large lenses, as dictated by the laws of physics. As such, you have to sacrifice a lot of zoom when you increase the sensor size, which is why those do-it-all travels zooms like your TZ-5 are a good compromise for many people.


October 31, 2011, 10:15 pm

Thanks Mike.

I'd be very interested to see if I could tell the difference though between shots taken on a normal DSLR and this Canon. I'm not sure I could easily. Comparing camera output is often tough as only rarely are comparison shots taken in the same light, of the same subjects.

Unfortunately reading the review and comments on the web it seems that this camera is limited by key features being disabled in manual mode, this means that things I'd want to do (like long exposure shots) are potentially not possible at all. Seems a big shame on a device this close to an SLR.

Will certainly take a look over the FZ150 too.


November 1, 2011, 2:30 pm

Hi AJ,
Sorry for the late reply - I was out of the office yesterday. It sounds like the as-ever well informed TR audience has pretty much done my job for me though :)

The IS works very well with video too - I didn't notice much jerkiness even with fast movement. The quality won't compare well with those DSLRs you mention though. It's good, but is still reliant on the quality of the sensor. For home movies it's fine, but if you want to go a bit Be Kind Rewind, you probably want something a little higher-end.


Mike B

November 13, 2011, 3:37 pm

One other point in the Panasonic FZ150 favor is the flash hot shoe. This enables you to use a bounce flash which always gives far better indoor results than a forward firing inbuilt flash. OK you need to fork out about £150 for a decent flash but it is worth the money if you take a lot of indoor shots. If you decide on a G3 or GH2 then you can se the flash on these.


December 9, 2011, 7:00 pm

Well I bought the camera and I love it.. You CANT tell the difference unless you are some PRO that is just the best.. lol.. Also you can do the long image shots with lights. Here is a video I found on Youtube that talks about it and It is a great camera.. Let me know what you think.. Patrick

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