A570is vs S410 Low light

[a570is]

Hi all,

I just got an A570 IS as an "upgrade" to my trusty S410. My S410 has been an awesome camera it is still going strong taking beautiful pictures. I got the A570 because it has controls over the aperture and the shutter speed.

I've been doing some test shots with both cameras and I must say I am disappointed with the A570's low light performance. A side by side comparison of the same shot shows that the S410's picture is sharper and less noisy. I put both A570 in Program mode ISO80 and S410 on M with ISO50. Shot the same scene from the same location under the same light (both camera rested on the same stable surface and shots taken with 2-sec timer). S410's picture is clearly superior...

I haven't a comparison test under regular and bright light but I'm heart broken because I love taking low light pictures...

If someone owns both cameras and/or can comment on what I'm seeing that would be great.

[eccles]

I can't help you, only explain what is going on.
Unfortunately, Canon has followed other manufacturers in the largely pointless megapixels war, cramming more and more pixels into tiny sensors. The result is almost always going to be either noise, or detail masking noise reduction. The 4 mp S410 has a 1/1.8" sensor, whereas the A570 has 7 mp crammed into a smaller 1/2.5" sensor, barely half the surface area of the S410.
To be fair, because of the more versatile shooting options and image stabilisation, the A570 will probably take pictures in good light that are maybe better than your S410. For noisy pictures, some form of post processing software such as 'Neat Image' will help.

[Jon]

Can you post the examples, with EXIF info? The A570 is using a higher ISO setting, which settings tend to be noisier. Another factor is that if your particular A570 underexposes relative to your S410, you'll see more noise. Given the three years difference in the technology between the two, I wouldn't be so quick to label it "smaller sensor" without seeing the examples, and the actual exposure settings used.

[a570is]

Thank you both for the reply. I've posted a couple pictures on Putfile:

http://www.putfile.com/nivek-photo/images/133524

but they're not the full resolution photos. The noise is evident when you look at them at 100% on the computer screen. Also, the white balancing is off a bit between them, I don't know if that will affect the resolution. If anyone know of a good place where I can upload the full size pictures, please let me know.

Lastly, I noticed that sometimes the IS introduces more noise into the picture.... That is, with the A570 sitting still, no IS shot is cleaner and sometimes sharper than one with IS turned on...

When I have time, I will try to do a more careful and systematic comparison.

Thanks.

[Jon]

Well, those are all, at 1 sec., long exposures. Most digital sensors will show noise at 1 sec. or longer exposure; this is caused in part at least by the sensor heating up with prolonged activity. I see the composition varying among the shots, which will affect the white balance (since on AWB it'll try to "average" things to a medium grey, just like it does an exposure). In additon, the A570 shots look somewhat underexposed relative to the S410 shots. The metering algorithms have changed over time, and been refined to give more "correct" results; unfortunately, for your example shots, this means lots of nice dark areas, which show noise much more than light areas.

If you're using the A570 on a tripod it's not unlikely that it, like early generation IS EF lenses, needs to have the IS turned off so it doesn't get caught in a "feedback loop", where it's looking so hard for motion that it starts creating its own motion when it doesn't find any real motion.

[a570is]

Thank you Jon, you have been very helpful. I don't remember my S410 having that much noise in low light situations. Are the ISO settings dictated by camera hardware (ie. the CCD)?

Why is it that the lowest ISO for S410 is 50 and for the A570 is 80?

[Jon]

Hardware, yes, but not just the CCD. As for the speed change, probably because Canon engineers considered ISO 80 on the circuitry used in the A570 was good enough to make it the baseline. Not everyone will agree with this.