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Old Mar 3, 2010, 12:55 AM   #21
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Shoturtle:

Again you keep talking about the G1, which has nothing to do with this, and technically isn't really even the same size sensor, since the variable aspect sensor has to be slightly larger.
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Old Mar 3, 2010, 1:05 AM   #22
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Both the G1 and GH1 has the same issue with iso above 800. If they perform better at high iso, why do you not see 12800 or at least 6400 iso on m4/3
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Old Mar 3, 2010, 2:21 AM   #23
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Originally Posted by shoturtle View Post
Ken,

You are fighting the laws of physic and it is a losing battle. Sorry to say. I say it again, I think the panny line up is a great setup. But again it is base on what you shoot. And low light is something that it is not suited for without a tripod and long exposures.
Shoturtle,

You are the one ignoring the physics, when you claim that one sensor size must be limited by physics to 800 ISO, while in the next sentence recommending people to use ISO 12,800 on a sensor size that is only fractionally larger.

I'm aware that there is an inherent advantage in the slightly larger sensor, and I thought I made clear in my very first post that more typically a four-thirds sensor would be expected to be a half stop worse than the largest APS-C sensor (Nikon). That statement was based on the physics. I'll add that it should be about 1/3 a stop behind the smaller Canon APS-C.

The plain physics is, you need to double the area to double the light, which is how you add 1 stop. So since the Canon sensor is only 1.37 times the area of the standard four-thirds sensor, that would be just over a third of a stop. So if you really think ISO 12,800 is acceptable on a Canon APS-C, your initial expectation based on the sensor size ought to be for ISO 9,343 to be of the same quality on four-thirds. And for ISO 4,672 to be equivalent to ISO 6,400. And ISO 2336 to be about the same quality as ISO 3200. And ISO 1168 similar to ISO 1600.

Another way of looking at it is you would expect to have about the same low light capability with the 20mm f1.7 on four-thirds as you would with an f1.9 lens on Canon APS-C. All else equal in sensor design and technology of course. But, not all Canon APS-C perform exactly the same, nor do all Nikon APS-C, nor do all four-thirds. In this case, the original poster asked about a specific model which happens to outperform expectations somewhat.

I think you are making way too much of the sensor size, you are ignoring multiple reviews from professional reviewers who find little difference in image quality for this specific model, and you haven't really stressed the far more significant limitations for things like low light and sports action, which would be the lack of an optical viewfinder, the difficulties of an electronic viewfinder in some of these situations, and the fact that contrast detect auto focus is still behind phase detect (though much better on the Panasonic lens than on the Olympus offerings so far).

But, the original poster didn't specifically ask about low light, either. He seemed more concerned about whether there would be an impact on overall image quality. Not only should there be no major concerns there, but in the tests at DPReview it also outresolved both the 500D and D5000. Perhaps one criticism might be that the JPEG processing isn't as good as Olympus.

I suppose the big question with this camera is how important is HD video? If that's a major attraction, this is one of the best implementations you will see in a hybrid. The contrast detect focus here is faster than what is available (in contrast detect) on a DSLR in this price range. If video isn't important, there might be cheaper ways to get the same still image quality.

Last edited by kenbalbari; Mar 3, 2010 at 7:51 AM.
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Old Mar 3, 2010, 7:43 AM   #24
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Both the G1 and GH1 has the same issue with iso above 800. If they perform better at high iso, why do you not see 12800 or at least 6400 iso on m4/3
Because it would look like this?

The point is there is little difference at the same ISO, between this, this, and this.
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Old Mar 3, 2010, 8:03 AM   #25
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BTW, what's the difference between 4/3 and micro 4/3 ?
The difference is the micro 4/3 is designed for the mirrorless cameras. Removing the mirror allows a shorter distance from lens to imager, and thus even smaller lenses.

The regular 4/3 lenses are used on the DSLR models, and will work only with an adaptor on the newer micro 4/3 (mirrorless) cameras, and most of them without autofocus (or at least with only very slow autofocus, which Olympus calls focus assist), because the phase detect autofocus used in DSLRs requires the mirror. Though some of the newer 4/3 lenses designed for contrast detect focus will work better.
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Old Mar 3, 2010, 9:02 AM   #26
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You just prove my point. Even with m4/3 iso eq to apsc at roughly 9000 iso, you can not even get past 1600 let alone 9000 on M4/3. The panny are great cameras, but the are not low light camera, no matter how good the sensor quality is. The Panny G series is not a low light performer. For all shooting upto 800iso the panny G1 and GH1 are great in IQ. There is no doubt about that with all the photos posted here and else where.

Quote:
Originally Posted by kenbalbari View Post
Shoturtle,

You are the one ignoring the physics, when you claim that one sensor size must be limited by physics to 800 ISO, while in the next sentence recommending people to use ISO 12,800 on a sensor size that is only fractionally larger.

I'm aware that there is an inherent advantage in the slightly larger sensor, and I thought I made clear in my very first post that more typically a four-thirds sensor would be expected to be a half stop worse than the largest APS-C sensor (Nikon). That statement was based on the physics. I'll add that it should be about 1/3 a stop behind the smaller Canon APS-C.

The plain physics is, you need to double the area to double the light, which is how you add 1 stop. So since the Canon sensor is only 1.37 times the area of the standard four-thirds sensor, that would be just over a third of a stop. So if you really think ISO 12,800 is acceptable on a Canon APS-C, your initial expectation based on the sensor size ought to be for ISO 9,343 to be of the same quality on four-thirds. And for ISO 4,672 to be equivalent to ISO 6,400. And ISO 2336 to be about the same quality as ISO 3200. And ISO 1168 similar to ISO 1600.

Another way of looking at it is you would expect to have about the same low light capability with the 20mm f1.7 on four-thirds as you would with an f1.9 lens on Canon APS-C. All else equal in sensor design and technology of course. But, not all Canon APS-C perform exactly the same, nor do all Nikon APS-C, nor do all four-thirds. In this case, the original poster asked about a specific model which happens to outperform expectations somewhat.

I think you are making way too much of the sensor size, you are ignoring multiple reviews from professional reviewers who find little difference in image quality for this specific model, and you haven't really stressed the far more significant limitations for things like low light and sports action, which would be the lack of an optical viewfinder, the difficulties of an electronic viewfinder in some of these situations, and the fact that contrast detect auto focus is still behind phase detect (though much better on the Panasonic lens than on the Olympus offerings so far).

But, the original poster didn't specifically ask about low light, either. He seemed more concerned about whether there would be an impact on overall image quality. Not only should there be no major concerns there, but in the tests at DPReview it also outresolved both the 500D and D5000. Perhaps one criticism might be that the JPEG processing isn't as good as Olympus.

I suppose the big question with this camera is how important is HD video? If that's a major attraction, this is one of the best implementations you will see in a hybrid. The contrast detect focus here is faster than what is available (in contrast detect) on a DSLR in this price range. If video isn't important, there might be cheaper ways to get the same still image quality.
.
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Old Mar 3, 2010, 9:27 AM   #27
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You just prove my point. Even with m4/3 iso eq to apsc at roughly 9000 iso, you can not even get past 1600 let alone 9000 on M4/3. The panny are great cameras, but the are not low light camera, no matter how good the sensor quality is. The Panny G series is not a low light performer. For all shooting upto 800iso the panny G1 and GH1 are great in IQ. There is no doubt about that with all the photos posted here and else where.
Huh?

You are obviously in denial, or not paying attention.

The GH1 does ISO 3200 as well as the Canon 7D.

The G1 doesn't, and is more comparable to your EPL-1.

That and fast glass, with stabilization, is as much as I would ever need in low light.
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Old Mar 3, 2010, 11:17 AM   #28
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3200iso, the EPL-1 does that too. But that is where these sensor do not perform, it is very very noise at any past 1250iso. At 1600iso from the sample picture I took with identical settings, the aps-c out performs m4/3. The proof is right there. If you like I can post 3200 from a m4/3 vs apsc tonight.
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Old Mar 3, 2010, 12:04 PM   #29
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3200iso, the EPL-1 does that too. But that is where these sensor do not perform, it is very very noise at any past 1250iso. At 1600iso from the sample picture I took with identical settings, the aps-c out performs m4/3. The proof is right there. If you like I can post 3200 from a m4/3 vs apsc tonight.
I agree, and the EPL-1 is clearly not as good as the GH-1. I think pretty much every review would agree with that. The DXOMark tests certainly make that clear. Sample photos are available from sites like this one, DPReview, imaging-resource, etc., demonstate it well enough.

But again, this thread wasn't asking about the EPL-1, it was asking about the GH1.

You keep insisting the GH1 is the same as the G1, again, it's clearly not. Compare samples from any source:

G1
GH1
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Old Mar 3, 2010, 12:54 PM   #30
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No, it was not but it is a m4/3 sensor, and they are limited in their low light ability by the laws of physics. That is all. I do not want to miss lead Marcelo in the performance of the m4/3 camera in low light. This is not what they excel in.
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