[rtpguy]

With Falks images with the A77 at camera set ISO 1600 vs K5 and A580 @3200 - how much does Pentax's 'unable to disable in reality' NR come into play?
The image sizing for the watch and some other shots isn't exactly looking like the same focal length and/or cropping factor/percentage, which seems like it would bias a fair amount.. ?

[ManuH]

In their own words: "we lose between 1/3 and 2/3 stop, which -unless a more translucent material is found- is the best Sony could come up with"

I don't understand that one. If more light is transmitted to the sensor, some will be lost for the AF if I'm not mistaken. Not necessarily wanted to gain 1/3 stop and lose AF performance.

[Sperdynamite]

The ISO definitely doesn't change. The meter is just calibrated to adjust for it... And honestly it's less than 1/3rd stop not a big deal.

However...that noise performance is AWEFUL. I DO NOT WANT THAT SENSOR. NEX-7 and A77 are steps in the wrong direction if you ask me.

So glad I have a K-5 and an X100.

[Winder]

The ISO definitely doesn't change. The meter is just calibrated to adjust for it... And honestly it's less than 1/3rd stop not a big deal.

However...that noise performance is AWEFUL. I DO NOT WANT THAT SENSOR. NEX-7 and A77 are steps in the wrong direction if you ask me.

So glad I have a K-5 and an X100.

There is a lot more that goes into IQ that just the sensor. Each company will use their own AA/color filter. Each company will use a different image processor. Until Adobe/C1/DxO release support for the A77 and the NEX-7 we wont have a good RAW processor to compare the images with.

We know Sony is losing 1/3 stop of light to the mirror.
We know Sony has a poor JPEG engine compared to Nikon or Pentax.
We know all of the companies are using different image processors.
We Know the Sony RAW converter is below average.

I realize most people don't print anymore and 100% crops taken at 12,000 ISO are the only way to judge images these days, but it is still a little early to consider the 24MP sensor a high ISO dog. Until I get to print some images processed in LR and printed at 13"x19" I'll hold judgement. I think Pentax (no mirror in the way) can at least match the K-5 performance. Remember that Pentax is applying NR at high ISO and Sony is not.

[falconeye]

I don't understand that one. If more light is transmitted to the sensor, some will be lost for the AF if I'm not mistaken. Not necessarily wanted to gain 1/3 stop and lose AF performance.

Even if AF would work well with less light, we don't know if a semitransparent mirror reflecting only this little light and not creating too much ghost images exists.

And honestly it's less than 1/3rd stop not a big deal.

We know Sony is losing 1/3 stop of light to the mirror.

It is 1/2 stop.

50% light loss would be a full stop. 30% light loss which is what the SLT mirror does, is 1/2 stop.

And it may be right that 1/2 stop isn't a big deal. But then, please stop to care about the difference of a DxO low iso score of 800 vs. 1200 ...

I doubt it can be better "dynamic range" wise : -0,9 EV as measured by DxO.

Ok, I'll try one more time ...

Currently, there is only ONE comparison in the DxO database which is meaningful:

Sony A-77 vs. Sony A-35.

It is meaningful because both cameras are similiar enough (e.g., both are 12 Bit, are Sony and have the SLT mirror). And it is meaningful because the A-35 has the K-5 sensor. Ignore all other comparisons. And no, we don't have to wait for the NEX-7 test.

And then you'll find:
A-77 sensor vs. sensor used in the K-5:
- Identical SNR18% noise performance (aka low iso noise)
- DR improved by 0.1 EV (I'll ignore the even better ISO 50 value because the K-5 already applies the extended ISO 80 setting and 80->50 is what the SLT mirror provides.).
- Tonal and Color sensitivity are identical.

According to current best available wisdom, the Sony 24MP and 16MP sensors perform exactly the same. Only the 24MP sensor has more pixels of course.

100% crop image to image comparisons don't say otherwise as they all compare apples to oranges. As I tried to illustrate in an earlier posting.

So, please everybody, stop jumping to conclusions here. Shoot, resize for the web (or the printer does it for you) and you'll see...

[Class A]

So, please everybody, stop jumping to conclusions here. Shoot, resize for the web (or the printer does it for you) and you'll see...

Amen.

[ogl]

Originally posted by falconeye* So, please everybody, stop jumping to conclusions here. Shoot, resize for the web (or the printer does it for you) and you'll see... Amen.

Let it be

[ogl]

Even if AF would work well with less light, we don't know if a semitransparent mirror reflecting only this little light and not creating too much ghost images exists.


So, please everybody, stop jumping to conclusions here. Shoot, resize for the web (or the printer does it for you) and you'll see...

It's very interesting, of course...But, studio shots from Dpreview says that A77 is noise generator in RAW at all ISO.

[rawr]

Half a stop of light loss doesn't sound much, but it looks like this:


(screencap from Digitalrev review of the A77):
Sony Alpha SLT-A77 Hands-on Review - DigitalRev.com

It also means your expensive fast glass will meter half a stop slower, so won't be fast glass anymore

[RonHendriks1966]

It is meaningful because both cameras are similiar enough (e.g., both are 12 Bit, are Sony and have the SLT mirror). And it is meaningful because the A-35 has the K-5 sensor. Ignore all other comparisons. And no, we don't have to wait for the NEX-7 test.

And then you'll find:
A-77 sensor vs. sensor used in the K-5:
- Identical SNR18% noise performance (aka low iso noise)
- DR improved by 0.1 EV (I'll ignore the even better ISO 50 value because the K-5 already applies the extended ISO 80 setting and 80->50 is what the SLT mirror provides.).
- Tonal and Color sensitivity are identical.

According to current best available wisdom, the Sony 24MP and 16MP sensors perform exactly the same. Only the 24MP sensor has more pixels of course.

100% crop image to image comparisons don't say otherwise as they all compare apples to oranges. As I tried to illustrate in an earlier posting.

So, please everybody, stop jumping to conclusions here. Shoot, resize for the web (or the printer does it for you) and you'll see...

My idea to wen I looked at A77 versus A55 versus K-5. When A77 is better then A55 and K-5 is better then A55 then in K-3 that sensor should perform very good.

I only hoped for a jump in performance, and not for a jump in pixels at the same performance.

What is the gain in goin 14-bit instead of 12-bit?

[Zygonyx]

Why can we see performance differences btw A55 and A35 though ? Don't they use same sensor ?

[Tord]

I'd prefer a full format Pentax with 16MP over a APS-C with 24!

[Winder]

My idea to wen I looked at A77 versus A55 versus K-5. When A77 is better then A55 and K-5 is better then A55 then in K-3 that sensor should perform very good.

I only hoped for a jump in performance, and not for a jump in pixels at the same performance.

What is the gain in goin 14-bit instead of 12-bit?

If you are printing you will see an improvement in performance. My Canon 5D has almost the same S/N of the Sony A900 but 2x the MPs. The result is that the noise appears as a much finer grain and is more pleasing. If the K-3 (or what ever it is called) does use the 24MP sensor then I think you will see a noticeable improvement in in the final output over the K-5. You have to equalize output to be able to judge the results. That is the problem with DPR and some other review sites is that they don't equalize and compare final output. You can not compare a 100% crop from a 24MP and a 100% from a 16MP on a monitor and get an accurate view of performance.

As far as the K-3 goes. I would hope that Pentax has other improvements that will be implemented.
Faster AF with more AF points. (smaller and more accurate) The golf ball sized center AF point is not cutting it.
Faster SR. Sony uses Eye detection for the SR. As long as you hold the camera to your eye it is active. Pentax's SR needs improvement.
2 SD card slots
Larger OVF with better magnification to keep stay ahead of the improving EVFs that are coming to market.

The biggest improvements in IQ have been in RAW processors. The more "megapixels" (to use the term loosely) the camera has the more information the RAW converter has to work with. This makes it easier for the RAW converters to determine what is noise and what is texture. This means that even if two cameras have the same S/N ratio the one with more MPs will process out better and produce a better image.

[jsherman999]

...
100% crop image to image comparisons don't say otherwise as they all compare apples to oranges. As I tried to illustrate in an earlier posting.

+1. Can't do 100% crops with different sensor resolutions to see 'noise' performance. That should be a given in folk's minds by now.

Basically, if the K-3 has that sensor, it looks like it will be just as good as the K-5 in DR and SNR - maybe a bit better - and have more MP, more cropability. Prints will look incredible.

.

[jsherman999]

I'd prefer a full format Pentax with 16MP over a APS-C with 24!

Me too

Over everything right now though I'd prefer a 24MP FF sensor at this performance level in a FF K-1.

.