A57 or A65 for lowlight wildlife?

Started Oct 28, 2012 | Questions thread
philbot Contributing Member • Posts: 846
Re: A57 or A65 and the "look of the noise"

Robsphoto wrote:

Thanks Sensibill for a sensible reply!

"Zackiedawg" recently made this interesting observation about the "look of noise":

"Whether JPG or RAW, I find judging the look of the noise to be much more important than the amount of it, and how the NR deals with it. I always strongly favored the fine-grained, uniform, luminance noise profile that the 16MP APS-C sensor produces, and did have a bit of a problem with the chunkier, more chroma, blotchier type noise that the 24MP APS-C sensor produces. When it came to noise reduction in camera, the blotchier and more chroma noise is harder to remove cleanly, which I think is why there are often so many complaints about the A77's high ISO look in JPG."


So, this is another aspect to think of, it's not just the "amount" of noise that's important, but also the "look" of the noise, as you also referred to in your post.




I can see where your source is coming from, I've been through that mill myself..

Firstly JPEGs,

When the 24MP first came out, that sentiment was quite rightly dscussed on the forums, the blotchiness of the 24MP was worse, and it looked more plasticky.

However, that was always comparing A33/A55 to A65/A77, which have a different generation Bionz processor and therefore JPEG engine which had more NR at higher ISOs by default.

The A57 has the same bionz processor as the A65/77, and shares the unfortunate same default JPEG behavior,

e.g. look at DPReviews ISO6400, the newer Bionz has a much more NR'd and plasticky look then the previous generation A55.

A65/57/55 ISO6400 JPEG NR comparison


The RAWs are another story, most RAW converters don't seem to deal with the 24MP RAW files that well, I always assumed it was as you'd expect at face value, just a side effect of the 24MP pixel size, and that blotchiness after even moderate NR was always still present.

But, ACR seems to have come on leaps and bounds, they've either improved their NR techniques overall, or they've revisited and improved the default processing for the 24MP sensor. Whatever the reason, it's ability to eliminate the Chroma issues and maintain fine detail with a much more pleasing fine grained luminance look is second to none.

As part of this and other discussions on 24/16 MPs, you can see many examples of how well ACR cleans things up..

Take this A57/A65 comparison, the A65 is using a tiny amount of Chroma NR only, and the grain can be made even finer using a smaller sharpening radius, and a hint of luminance NR will reduce the contrast of the noise whilst being able to retain the nice grain..

It's shown against the no NR'd A57 for comparison. The A57 can clean up from that of course, but the maximum detail/grain is about the same for each..

Here's a side by side No NR/Tiny amount of Chroma NR on the A65, just to show the different in noise grain.

Again, you can improve these further by adding a hint of sharpening with a much smaller radius and a touch of luminance NR to reduce the grain contrast in ACR..

Using Aftershot Pro or Capture One, they seem to not remove the Chroma noise effectively, and can't get anywhere near ACR at the moment.. I don't know exactly where in the chain of processing they differ, but they could do with looking at Adobe for at least this sensor..

Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow