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DxOmark data for the Pen EP-1 available

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simpy

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Just up on the DxOmark site is the data for the Pen EP-1: http://www.dxomark.com/index.php/eng/Image-Quality-Database/Olympus/PEN-EP1

[please, don't flame me if you disagree with the way they compute their single-number DxOmark result; just look at the data]

Looking at the charts, it seems pretty much identical to the Olympus E-30: not unexpected. In real life, it could translate into slightly better noise performance due to the weaker AA filter, requiring less sharpening.

Also interesting is that if you shoot raw, there doesn't seem to be much to be gained by shooting at ISO values higher than 800. The drop in dynamic range from there onwards is approx. 1 stop for every ISO step. That means you may just as well drag the exposure slider in the raw converter in post processing. This has the additional advantage that it retains more information in the highlights.

Simon
 
simpy said:
Just up on the DxOmark site is the data for the Pen EP-1: http://www.dxomark.com/index.php/eng/Image-Quality-Database/Olympus/PEN-EP1

[please, don't flame me if you disagree with the way they compute their single-number DxOmark result; just look at the data]
Click to expand...
EP-1 measured ISO is about a stop behind that of the G1; otherwise they are almost identical. Slight glitch in DR where GI DR at indicated 800ISO is rather better than EP-1 at 1600. Just remember when making comparisons that the G1 is running a stop faster than the EP-1 at indicated ISOs.

Of course, I don't know how good DxOmark is.

Mike
--
Mike Davis
Photographing the public for over 50 years
http://www.flickr.com/photos/watchman
G1 FZ50
 
nick_webster said:
Apart from measurebators that is ?
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Do you have anything to add except for insulting me by implication?

As you may have noticed, in my OP I have mentioned that these numbers tell you that it's not much use to use ISO1600 and higher if you shoot raw. Just one of the things these numbers can tell you if you take the time to think about them.

Simon
 
So, for example, the D700 at iso1600 has more dynamic range than the EP1 at iso200. ... also, Oly is severely overstating their iso values, perhaps to appear to be good at high iso.. eg. iso1600 is measured at 1k.
 
Jogger said:
also, Oly is severely overstating their iso values, perhaps to appear to be good at high iso.. eg. iso1600 is measured at 1k.
Click to expand...
There is also a alternative, 'good', explanation for this. The definition of the ISO values is not very strict. What Olympus has done in its latest models is to supply the highlight headroom that users were asking for and were familiar with in Nikon and Canon models (they do the same).

Simon
 
simpy said:
Jogger said:
also, Oly is severely overstating their iso values, perhaps to appear to be good at high iso.. eg. iso1600 is measured at 1k.
Click to expand...
There is also a alternative, 'good', explanation for this. The definition of the ISO values is not very strict. What Olympus has done in its latest models is to supply the highlight headroom that users were asking for and were familiar with in Nikon and Canon models (they do the same).
Click to expand...
Oh for sure, others do it as well and i know its not a perfect science. But, that iso1600 value for example, is a 60% mark-up from the measured 1000... which, i dunno, since there isnt a strict def't of iso,.. i guess that is ok. Others do it too.
simpy said:
Simon
Click to expand...
 
Jogger said:
Oh for sure, others do it as well and i know its not a perfect science. But, that iso1600 value for example, is a 60% mark-up from the measured 1000... which, i dunno, since there isnt a strict def't of iso,.. i guess that is ok. Others do it too.
Click to expand...
If you disregard the 'actual' value, which is pretty arbitrary anyway, this only means that Olympus has decided to increase the highlight headroom by 2/3 of a stop at the cost of a little shadow noise.
 
hmm, according to this test G1 iso3200 should be more sensitive than EP1 iso6400.

from my own tests i have noticed a slightly higher sensitivity of G1 compared to EP1, but it was maybe 1/3 stop not a full stop...
 
oluv said:
hmm, according to this test G1 iso3200 should be more sensitive than EP1 iso6400.

from my own tests i have noticed a slightly higher sensitivity of G1 compared to EP1, but it was maybe 1/3 stop not a full stop...
Click to expand...
Are you comparing the raw files relative to the clipping point? Because that is what they do...

Simon
 
...thanks for posting. But I have to admit, just my personal opinion, DxO has never impressed me. There has been to many times that the "numbers" did not coincide with my real world experience. Cheers. -Norm
 
...as long as you keep in mind that the data indicate the RAW performance of the sensor, and as long as you don't make too much of small numerical differences, e.g., assuming that a sensor with a DxOMark rating of 55.8 is significantly better than one with a rating of 55.6. The ratings do tell us just what the actual differences in sensor performance are, and provide a guideline for deciding at what ISO the performance becomes unacceptable.

Bob
 
nboyer said:
...thanks for posting. But I have to admit, just my personal opinion, DxO has never impressed me.
Click to expand...
but their raw-converter is quite good. what a pity that it doesn't support G1 yet...
 
oluv said:
but their raw-converter is quite good. what a pity that it doesn't support G1 yet...
Click to expand...
Agree. It beat anything I saw when converting raw on the Canon G10. It's amazing. I wish they had one for the E-P1. I have asked for that on their suggestions page:

http://dxo (dot)com/us/photo/support/modules/availability/pb_availability

Please change (dot) to .

If more people fill that out, for the E-P1, G1, GH1, maybe they will consider Oly and Pan.

Michael
 
Jogger said:
So, for example, the D700 at iso1600 has more dynamic range than the EP1 at iso200.
Click to expand...
A meaningless comparison, since the S/N ratio comparison shows that the noise floor is equalized with a two stop ISO speed difference, as one would expect with a factor of four in sensor and photosite area. So the third stop of difference is apparently in headroom, not shadow depth. If one were concerned about highlight headroom at high ISO, that is an A/D clipping issue, not a sensor issue, so the EP-1 user can use ISO 200 one stop underexposed vs ISO 1600 on the D700 to get back to comparable shadow and highlight handling at about the expected two stop speed difference, assuming equal f-stop . And of course, the D700 needs a far bigger, heaver lens to get equal minimum f-stop at twice the focal length.

In summary: if you uses lenses that are twice as long and offering twice the maximum aperture diameter (same minimum f-stop) and thus with eight times the volume of glass, you get two stops more speed from the sensor of four times the area: the usual "big, heavy glass" advantage, which some people misinterpret as coming from the larger sensor alone.
 
They test cameras with their lenses on (as they have to with some of them where the lens can't be removed). When measuring ISO, they rely on 1) the reported aperture being absolutely correct 2) there being comparable light loss between 2 different lens systems. Since some of the more complex lenses can have up to 30% light loss, and since manufactures sometimes fudge their aperture ratings a bit, I don't see how they can compare sensor ISO this way. They ARE measuring some kind of overall light sensitivity assuming that the reported apertures are correct, but they are not measuring ISO which is an international standard for sensor/film sensitivity.
 
Bryan Biggers said:
They test cameras with their lenses on (as they have to with some of them where the lens can't be removed). When measuring ISO, they rely on 1) the reported aperture being absolutely correct 2) there being comparable light loss between 2 different lens systems. Since some of the more complex lenses can have up to 30% light loss, and since manufactures sometimes fudge their aperture ratings a bit, I don't see how they can compare sensor ISO this way. They ARE measuring some kind of overall light sensitivity assuming that the reported apertures are correct, but they are not measuring ISO which is an international standard for sensor/film sensitivity.
Click to expand...
Andy Westlake goes into more detail here about their testing
http://forums.dpreview.com/forums/read.asp?forum=1018&message=32965502

--
http://illy.smugmug.com
 
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