Photoclubalpha

I have had my A700 for a while now, and I find that the "best" looking images for my computer and forum post seemed to be at the 6meg Medium setting.
I usually shoot cRaw & jpeg, so I always have a full 12 meg image if I want to use it.

I guess I just wonder HOW the 6 meg images is produced from the 12 meg sensor. I haven't found an explanation of the process
and I wonder why the 6 meg images might look better to me.

I figured if anyone knew the working of the Sony 12meg sensor, it would be here.

Thanks for any explanation you can provide.

Regards,

Rick

The 6 meg image is calculated from the RAW file, which always exists even if you do not save raw. It is not a result of 'binning' at the sensor, and there is no evidence that an intermediate 12 megapixel conversion is created then downsampled - this seems unlikely as the sequence shooting rate is better when selecting Medium or Small JPEG.

As with the Alpha 350, selecting the Medium size makes a big difference with higher ISO shots, on the Alpha 700 it is beneficial at 3200 ISO. The JPEG seems to be extracted from the raw file using a larger convolution, more Bayer pixels going to make up each JPEG pixel, and that smooths out noise really well.

David

David,
Thanks for the reply and explanation.

So is there any downside to shooting with the medium image setting other than printing large size prints?

You say the high ISO is somewhat better, but is there some trade off to getting the better high ISO?

I find with the cRaw & jpeg(medium) I get a close to KM5D jpeg image, with the AF speed of the A700.
It works well for me, but others might disagree. If I shoot just jpeg, then I bump up to large image size, to have more pixels to use.

I believe I had read on your site sometime ago, that you had done some work using the 6meg medium setting on the A700,
and found it to be useful. Did you find any distinct problems with that?

Thanks again,

Rick

There is no trade-off except loss of detail as expected by sizing down from 12 to 6 megapixels. The 6 megapixel JPEG can be expected to be better than a typical 6 megapixel DSLR JPEG because the source image is oversampled (in effect).

David