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09-23-2011, 09:51 AM   #241
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Comparing the Sony A77 to the Nikon D7000, the D7000 has a Sports low light ISO available of 1167 vice the A77 iso available of 801, which is 1/2 ev better performance from the D7000.

Its probably more relevant to see what this sensor can do inside the NEX 7 than consider the score as a result of the translucent mirror.

The Definition of this numerical criteria for Sports low light iso:

QuoteQuote:
Sports & action photography: Low-Light ISO
Unlike the two previous scenarios in which light is either generous (studio)
or stability is assured (landscape), photojournalists and action photographers
often struggle with low available light and high motion. Achieving usable image
quality is often difficult when pushing ISO.

When shooting a moving scene such as a sports event, action photographers’
primary objective is to freeze the motion, giving priority to short exposure
time. To compensate for the lack of exposure, they have to increase the ISO
setting, which means the SNR will decrease. How far can they go while keeping
decent quality? Our low-light ISO metric will tell them.

The SNR indicates how much noise is present in an image compared to the
actual information (signal). The higher the SNR value, the better the image
looks, because details aren't drowned by noise. SNR strength is given in dB,
which is a logarithmic scale: an increase of 6 dB corresponds to doubling the
SNR, which equates to half the noise for the same signal.

An SNR value of 30dB means excellent image quality. Thus low-light ISO is the
highest ISO setting for a camera that allows it to achieve an SNR of 30dB while
keeping a good dynamic range of 9 EVs and a color depth of 18bits.

A difference in low-light ISO of 25% represents 1/3 EV and is only slightly
noticeable
.


I suppose that when Pentax eventually puts this sensor in the follow-on to the K5, you won't be able to get the 16 megapixel in a Pentax model with all of the current "embellishment factors", i.e. extremely quiet shutter, etc.

My advice is get your K5 now, before its "improved"


Last edited by philbaum; 09-23-2011 at 09:57 AM.
09-23-2011, 10:11 AM   #242
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Good to see the K-x is still doing well @ 811 Low-light ISO vs the A77's 803.
09-23-2011, 10:16 AM   #243
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So the test is there from DxO:

DxOMark - Compare cameras side by side

When this a77 is better then a55, does it mean that it is even better on our K-3?
09-23-2011, 10:21 AM   #244
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Thanks for link, people were waiting for this with anticipation.

So, if Pentax (K-5) manages to score 2 points above Sony when using the same chip (A580) which in turn scores about 6 points over the same chip when paired with a translucent mirror (A35), we would conclude that the sensor alone has improved by 4 points despite the smaller pixels (DxO doesn't give points for resolution which is considered an independent dimension to score a sensor).

The major improvement seems to come from a slightly better image at very low iso. Low light noise (read, quantum efficiency) seems to remain the same.

All in all, it seems that upgrading to 24MP had no negative impact on IQ.


Disclaimer,
I should add that I don't understand why Sony has a lower DR than Pentax with the same sensor in their cameras. The translucent sensor should NOT reduce DR, only reduce the ISO where DR maxes out. Maybe, part of the progress made in the A77 is to copy what Pentax did. DR in the 24MP sensor then would not have improved, only Sony's ability to use the sensor.

09-23-2011, 05:04 PM   #245
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If Pentax only adds the new sensor there wont be many people who elect to upgrade. Pentax is going to need to improve other functions of the camera like AF, SR and add things like a second SD card slot, support for tethering, improve the VF (larger with better magnification).

If the 16MP and 24MP sensors are really that close then there real world advantage is small. I like the 24MP sensor for several reasons, but it is not a huge improvement over the 16MP, and for those with older computers the 24MP is not as attractive.
09-23-2011, 05:17 PM   #246
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To me, the biggest improvements in the A77 sensor are with regard to faster read out speeds. Seems more useful from a video standpoint, although certainly if you need 9 or 10 fps I guess it could be nice.

Otherwise, the K5 is perfect from a sensor standpoint. Still, I think the 16 megapixel sensor will end up in the kr sequel and this 24 megapixel will end up in the K3 or whatever it will be called.
09-23-2011, 05:50 PM   #247
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Pentax may elect to use the Samsung 20MP in the next K-# body. We will have to see how it stacks up. It is going to be interesting to see what the market does. What is Nikon going to do?

I hope that the strong push by Sony with the EVF will push Pentax (and others) to improve the quality of their OVF to keep and advantage. I would love to see Pentax release the K-3 with a larger OVF with a higher level of magnification. It would make all of the MF lenses that much better.
09-23-2011, 11:01 PM   #248
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QuoteOriginally posted by Winder Quote
Pentax may elect to use the Samsung 20MP in the next K-# body. We will have to see how it stacks up. It is going to be interesting to see what the market does. What is Nikon going to do?

I hope that the strong push by Sony with the EVF will push Pentax (and others) to improve the quality of their OVF to keep and advantage. I would love to see Pentax release the K-3 with a larger OVF with a higher level of magnification. It would make all of the MF lenses that much better.

The samples I've seen from the Samsung NX200 actually seem better than what I've seen from the Sony 24MP sensor so maybe it would be better?

09-24-2011, 02:49 AM   #249
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QuoteOriginally posted by Rondec Quote
To me, the biggest improvements in the A77 sensor are with regard to faster read out speeds. Seems more useful from a video standpoint, although certainly if you need 9 or 10 fps I guess it could be nice.

Otherwise, the K5 is perfect from a sensor standpoint. Still, I think the 16 megapixel sensor will end up in the kr sequel and this 24 megapixel will end up in the K3 or whatever it will be called.
+1 on that, but K-3 needs a big improvement on electronics and processing to handle all those new and faster coming data.
09-24-2011, 11:07 AM   #250
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QuoteOriginally posted by markac Quote
The samples I've seen from the Samsung NX200 actually seem better than what I've seen from the Sony 24MP sensor so maybe it would be better?
Pentax has been using Fujitsu Milbeaut image processors and the 6th generation of the Milbeaut processor was released this year. It handles 20MP at 5.5 frames per second. 14MP at 8 frames per second. Maybe Pentax will be using a different image processor, but Fujitsu was used in the K-20, K-7, & K-5. The Milbeaut has been a very good image processor for Pentax.

If Pentax is going to run 2 processors and redesign the body then I could see them going with the Sony 24MP. Running 24MP at 14-bit is going to take some serious processing power. Time for a new body with room for 2 image processors, 2 SD cards, and a larger VF to stay ahead of the EVF technology.
09-24-2011, 11:57 AM   #251
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QuoteOriginally posted by Winder Quote
Pentax has been using Fujitsu Milbeaut image processors and the 6th generation of the Milbeaut processor was released this year. It handles 20MP at 5.5 frames per second. 14MP at 8 frames per second. Maybe Pentax will be using a different image processor, but Fujitsu was used in the K-20, K-7, & K-5. The Milbeaut has been a very good image processor for Pentax.

If Pentax is going to run 2 processors and redesign the body then I could see them going with the Sony 24MP. Running 24MP at 14-bit is going to take some serious processing power. Time for a new body with room for 2 image processors, 2 SD cards, and a larger VF to stay ahead of the EVF technology.
So this is much faster then the current PRIME II or is just the writetime the thing holding us back at the time? In future even UHS-I can't catch up with the amount of data that is processed.
09-24-2011, 05:50 PM   #252
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QuoteOriginally posted by RonHendriks1966 Quote
So this is much faster then the current PRIME II or is just the writetime the thing holding us back at the time? In future even UHS-I can't catch up with the amount of data that is processed.
From a speed stand point it is not much different that the current image processor. It is faster, but not significantly. If Pentax is going to use the Fujitsu processor and the 24MP Sony sensor we might see a drop in FPS, unless they are going with 2 processors. Of course the Samsung 20MP would mean 5.5 FPS.

The advantage is in HD video and true 1080. Fujitsu makes good processors. They are used by Leica in the S2 and probably the M series.
09-27-2011, 12:40 AM   #253
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https://www.pentaxforums.com/forums/non-pentax-cameras-canon-nikon-etc/160369...noise-raw.html

A77 has HUGE amount of noise in RAW from ISO200 and above.
K-5, 5D Mk II and D7000 are much better.

have a look - A77 at ISO200 is worse than K-r at ISO800....
K-7 is better too. He-he...
09-27-2011, 02:00 AM   #254
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QuoteOriginally posted by Winder Quote
From a speed stand point it is not much different that the current image processor. It is faster, but not significantly. If Pentax is going to use the Fujitsu processor and the 24MP Sony sensor we might see a drop in FPS, unless they are going with 2 processors. Of course the Samsung 20MP would mean 5.5 FPS.

The advantage is in HD video and true 1080. Fujitsu makes good processors. They are used by Leica in the S2 and probably the M series.
well then I'm not yet a big fan for going to 24 megapixel.
09-27-2011, 02:01 AM   #255
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QuoteOriginally posted by ogl Quote
https://www.pentaxforums.com/forums/non-pentax-cameras-canon-nikon-etc/160369...noise-raw.html

A77 has HUGE amount of noise in RAW from ISO200 and above.
K-5, 5D Mk II and D7000 are much better.

have a look - A77 at ISO200 is worse than K-r at ISO800....
K-7 is better too. He-he...
O my, I don't want to go back that road!
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