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A77 mk2 ISO weirdness??

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VirtualMirage said:
migue65 said:
You also used same focal length on the zoom for both right? Sorry for such a trivial question but I had to ask. Your test shows the numbers going in the wrong way for the m2. If this is the case, it is a deal breaker for me. I respectfully hope you missed something on your test.
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How are they going the wrong way?

Secondly, why would it be a deal breaker? ISO is just a film standard being converted to a digital world to give photographers a way to better interpret gain.

If ISO 200 on the A77II looks as good or better than ISO 100 on the A77, same goes for ISO 3200 versus the A77's ISO 1600, when using the same values elsewhere, why does it matter?
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Because it means there is no improvement in noise performance which is what migue65 is looking for.

If the ISO is set to 3200 on the MkII and looks as good as 1600 on the Mk I but in actual fact the ISO on the II is really 1600 there is no difference in noise performance.
VirtualMirage said:
The only impact, at worst, that will do is you will have to mentally remember that the A77II can and may need to go one ISO stop higher than the A77 but that doesn't mean it will be up to one stop noisier than the A77. While not exact, it's similar to the mentality for some of those that go from APS-C to Full Frame: they used to think they could go no higher than ISO 1600 and that thought carries over to their full frame, when in actuality they can go much higher in ISO and not degrade in image quality as much as they thought.
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Which does't apply at all here. With FF you get a genuine improvement in noise performance that (depending on the camera) my give you say 2 stops better noise performance.

So you could possibly set the ISO to 3200 and get an image as good as ISO 800 on aps-c.

What the O/P is saying that on the A77MkII is that ISO 3200 is really ISO1600. You are not getting MkI ISO 1600 performance at ISO 3200 on the MkII because its not a genuine ISO3200 if the O/P is correct.
 
Dave Oddie said:
VirtualMirage said:
From everything I have seen so far, whether it is a fraction of a stop or a full stop, the A77II is no noisier than the A77 and, if anything, is actually less noise, even at higher ISOs.

So what I was trying to say earlier, even if you have to go up to ISO 200 versus the A77's ISO 100, the noise so far reported and observed shows the A77II at ISO 200 being no noisier (if not less noisy) than the A77 is at ISO 100.
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It does? Where?
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My personal observations from owning both cameras. Do you own both cameras to tell me otherwise?
Dave Oddie said:
Sony only claim a 20% improvement. If what the O/P observed is true Sony are cheating.
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Quick to the accusations of cheating without having any foundation for such nor none of your words of experience to prove otherwise. What do 20% improvement in sensor sensitivity mean to you.
Dave Oddie said:
Dave Oddie said:
Substitute those ISO numbers for higher values and get the same conclusion (ie, ISO 1600 for A77 versus ISO 3200 for A77II).

So again, not a loss in image quality nor a gain in noise, just a different thought process needs to be used to remember the A77II can go to a higher ISO setting than the A77 can.
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But if its a stop out it is meaningless. Set the A77II to 3200 when in reality it is 1600 means its 1600 not 3200 despite what the camera says it is.
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ISO is just a number from the analog days that is being converted to a digital world with much leeway. The A77's ISO 1600 isn't a true ISO 1600 either. So you are comparing two cameras with inaccurate ISO measurements that also have what appears to be a difference in exposure weighing but insist on comparing the two to identical ISO numbers despite the discrepancies.

Read my earlier post in this thread that explains what I observed between the two when shooting the same target with the same lens.

At ISO 1600, F/4, 1/60s (the automated exposure the camera chose), the A77 overexposed middle grey by around .15-.2 stops. At IS3200, F/4, 1/60s (camera chose ISO for automated exposure), the A77II overexposed middle grey closer to .6 stops. If we were to add some form of exposure compensation to get them at middle grey, the ISO on the A77 would be around an unachievable 1450-1500 (since cameras can't adjust ISO in .15-.2 stop increments). The A77II would be around 2000-2100 by my guess. This would put the actual exposure difference between the two at only around .5 stops.

Time permitting, I want to do a more controlled test to determine the consistency of my initial 5 minute test results.
 
Dave Oddie said:
VirtualMirage said:
migue65 said:
You also used same focal length on the zoom for both right? Sorry for such a trivial question but I had to ask. Your test shows the numbers going in the wrong way for the m2. If this is the case, it is a deal breaker for me. I respectfully hope you missed something on your test.
Click to expand...
How are they going the wrong way?

Secondly, why would it be a deal breaker? ISO is just a film standard being converted to a digital world to give photographers a way to better interpret gain.

If ISO 200 on the A77II looks as good or better than ISO 100 on the A77, same goes for ISO 3200 versus the A77's ISO 1600, when using the same values elsewhere, why does it matter?
Click to expand...
Because it means there is no improvement in noise performance which is what migue65 is looking for.

If the ISO is set to 3200 on the MkII and looks as good as 1600 on the Mk I but in actual fact the ISO on the II is really 1600 there is no difference in noise performance.
Dave Oddie said:
The only impact, at worst, that will do is you will have to mentally remember that the A77II can and may need to go one ISO stop higher than the A77 but that doesn't mean it will be up to one stop noisier than the A77. While not exact, it's similar to the mentality for some of those that go from APS-C to Full Frame: they used to think they could go no higher than ISO 1600 and that thought carries over to their full frame, when in actuality they can go much higher in ISO and not degrade in image quality as much as they thought.
Click to expand...
Which does't apply at all here. With FF you get a genuine improvement in noise performance that (depending on the camera) my give you say 2 stops better noise performance.

So you could possibly set the ISO to 3200 and get an image as good as ISO 800 on aps-c.

What the O/P is saying that on the A77MkII is that ISO 3200 is really ISO1600. You are not getting MkI ISO 1600 performance at ISO 3200 on the MkII because its not a genuine ISO3200 if the O/P is correct.
Click to expand...
It might be wise to read the whole thread before responding to posts that have follow ups that go into further detail which either answers or refutes the response you are making.
 
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