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OMG!

kwalsh

New member
Just to go to the OMD, which if it uses the same sensor as the GX1, doesn't have as much DR as the GH2.

- Raist
The difference between the DR of the GX1 and GH2 is pretty small at base ISO. Don't be fooled by the flawed SNR measurement point at DxO that over-emphasizes the difference. Try actually pushing the shadows of the two sensors to a "useful" level and there is little difference between them. At 4 stops below middle gray the SNR is the same.

Which is not to say the GH2 isn't a little better, and I'd prefer to see GH2 sensors in future cameras.

Really, what is holding these sensors back for best base ISO performance is the saturation capacity. And that's identical between all the m43 sensors.

Ken
 

Godfrey

Well-known member
new leaked photo ...

http://i1266.photobucket.com/albums/jj524/picrumors/om-dlenses.jpg

I may be off into another world of equipment now, but I'm still excited.

Olympus has always made fine lenses, and fine cameras at the top end of their range, and this one looks like it has a lot of promise. It's good to see them moving forwards with the unique products that were always their hallmark.

Much nicer to see this than to read about one bit after another of corporate stupidity and greed.
 
M

Markus

Guest
Re: new leaked photo ...

http://i1266.photobucket.com/albums/jj524/picrumors/om-dlenses.jpg

I may be off into another world of equipment now, but I'm still excited.

Olympus has always made fine lenses, and fine cameras at the top end of their range, and this one looks like it has a lot of promise. It's good to see them moving forwards with the unique products that were always their hallmark.

Much nicer to see this than to read about one bit after another of corporate stupidity and greed.
I agree, Olympus are finally getting into the swing of things. They should have released something like this about a year ago and would have been pretty much ahead of the competition.

The 75/1,8 is promising - finally a AF version of the Pen F 70mm.

Maybe it's a good thing I haven't sold off my MFT lenses yet.
 

Jorgen Udvang

Subscriber Member
This reminds me a lot of the good, old OM days, and think about it; it's less than three years since Olympus launched the E-P1 and three years and a half since Panasonic started selling the G1. And now this:



In addition, all the Panasonic bodies and lenses, third party gear etc. Very impressive and this makes the choice for the way forward very easy for me.
 

raist3d

Well-known member
The difference between the DR of the GX1 and GH2 is pretty small at base ISO. Don't be fooled by the flawed SNR measurement point at DxO that over-emphasizes the difference.
Why exactly is it flawed?

Try actually pushing the shadows of the two sensors to a "useful" level and there is little difference between them. At 4 stops below middle gray the SNR is the same.
But total DR is shadow and also highlight DR. But I am all about seeing for myself. If you know of a good place with RAWS (photography blog I guess) Ill check it out. It's tough without having the same exposures but if the difference in the DR is as big as it seems, maybe at least a small inclination can be had towards believing what Dxo marked.

Which is not to say the GH2 isn't a little better, and I'd prefer to see GH2 sensors in future cameras.

Really, what is holding these sensors back for best base ISO performance is the saturation capacity. And that's identical between all the m43 sensors.
Ken
Hmm why is it identical between all m43rd sensors? I don't think all the designs have the same efficiency(?)

- Raist
 

kwalsh

New member
Why exactly is it flawed?
Maybe flawed is a strong word on my part. How about, "not photographically relevant". They measure DR where the signal-to-noise is 0dB - noise and scene detail are equal magnitude. This is a totally unusable shadow for a photographer - you'd never even try to use such a thing. 0dB is a nice arbitrary engineering measure, and one I understand is even used in many sensor datasheets. So it isn't like they are doing anything wrong using it.

The rub is that if the SNR curves were linear it wouldn't matter where they chose. 0dB, 10dB, -10dB - whatever - we are only comparing cameras and all that matters is the comparison, not the absolute value. The problem is that the curves are not linear at all. And at least at the moment with the technology right at base ISO many cameras have a bend in their SNR curve near this 0dB point. So what happens by choosing a "really noisy shadow" as their reference point they give more benefit to a camera with really low read noise than is really useful to a photographer. If they chose a higher SNR as their reference point (6dB, 10 dB?) the GX1/G3 and GH2 sensors would have closer DR. You can see this if you look at their "Full SNR" curve tab (not available in the compare feature, must go to the individual camera reviews). Imatest provides "DR" measurements for a few different SNRs with some different number crunching to try to be a bit more "photographically relevant".


But total DR is shadow and also highlight DR.
That's right. DxO just measures between a saturated sensor and an SNR of 0dB, so they get both shadow and highlight in one measurement - the choice of the grey point is arbitrary. The only problem is 0dB is just a bit too low to measure if our goal is to compare "usable" DR, as described above. When they started doing their measurements it was probably a non-issue, but now that we've got some incredibly low read noise sensors out there it is skewing the results in a way not practical to photographers.

But I am all about seeing for myself. If you know of a good place with RAWS (photography blog I guess) Ill check it out. It's tough without having the same exposures but if the difference in the DR is as big as it seems, maybe at least a small inclination can be had towards believing what Dxo marked.
DPReview has their studio shots, and they include a shadow box that is good for pushing to see how the shadow noise looks. The RAW files are downloadable. The problem is they really don't have a good highlight feature anywhere in the scene to make sure the camera hasn't just traded shadow range for highlight range. You can kind of get around this by verifying that the exposure was the same and then go look at DxO's ISO measurements for the cameras. Their ISO measurement is in fact just a measurement of the saturation level of the RAW file. By noting the exposures used in the DPR test and checking the DxO ISO measurement you can adjust how much you push the shadows for each camera for a "fair" comparison.


Hmm why is it identical between all m43rd sensors? I don't think all the designs have the same efficiency(?)
They don't, but they do have nearly the same saturation level (adjusted for sensor resolution differences) - by which I mean the maximum number of photons that can be collected before clipping. The measured ISO of the sensor relates to efficiency of course. However, if what we really want is nice clean mid-tones and the freedom to push and pull an exposure without noise showing up everywhere (not just the shadows) then we want to gather as many photons as possible so we will have the lowest photon shot noise. And this is set by the saturation level, which is just about the same for all the cameras (the GH1 is the odd man out here, slightly higher than the others but only by 1/3 of a stop).

Efficiency measures how fast "the well" fills up. Saturation measures how deep "the well" is. For best low ISO noise performance we want the deepest "well" possible but don't particularly care how fast it fills. For best high ISO performance our concerns are exactly the opposite - it could be a shallow well (we won't ever get to collect many photons anyway at high ISO) but we want it to fill efficiently.

Ken
 

kwalsh

New member
Will the tilting OLED be reversible (flipped 180º), to protect the surface when it is not in use?
No, not if it is like any of the others on Olympus or Sony cameras. The only ones that flip to face the camera back are the tilt and swivels like on the Panasonic G/GH series.

Ken
 

ggibson

Well-known member
Will the tilting OLED be reversible (flipped 180º), to protect the surface when it is not in use?
Doesn't look like it. It appears to be similar to the E-PL3 screen.

Also, did anyone else notice the double shutter buttons on the battery grip for both orientations?

I must say, this camera is incredibly tempting...
 

RichA

New member
NEX-7, GH2, G3, OM-D, Fuji X-Pro1????????????????

Likely, I will get the OM-D, provided there are no issues with it.
 

raist3d

Well-known member
Maybe flawed is a strong word on my part. How about, "not photographically relevant". They measure DR where the signal-to-noise is 0dB - noise and scene detail are equal magnitude. This is a totally unusable shadow for a photographer - you'd never even try to use such a thing. 0dB is a nice arbitrary engineering measure, and one I understand is even used in many sensor datasheets. So it isn't like they are doing anything wrong using it.
But I don't see this as an issue because the measurements are all equal for all cameras. So if a camera is ranked at 12 stops, and another at 10, I certainly would expect a comparative difference here.

The rub is that if the SNR curves were linear it wouldn't matter where they chose. 0dB, 10dB, -10dB - whatever - we are only comparing cameras and all that matters is the comparison, not the absolute value. The problem is that the curves are not linear at all. And at least at the moment with the technology right at base ISO many cameras have a bend in their SNR curve near this 0dB point. So what happens by choosing a "really noisy shadow" as their reference point they give more benefit to a camera with really low read noise than is really useful to a photographer.
But again, a camera with a sensor with a really low read noise can certainly have a lot of DR. If you expose to the right you are using it. Or by under exposing and developing up. This would move the DR to the highlights and cut in the shadows but if the shadows are that good you can afford to without much impact to image quality (specific case: K-5 sensor for example)

If they chose a higher SNR as their reference point (6dB, 10 dB?) the GX1/G3 and GH2 sensors would have closer DR. You can see this if you look at their "Full SNR" curve tab (not available in the compare feature, must go to the individual camera reviews). Imatest provides "DR" measurements for a few different SNRs with some different number crunching to try to be a bit more "photographically relevant".
But that would mean then that they are ignoring the DR in the shadows. Again, low shadow noise is equal to DR you can use- either when you expose to the right or under expose and develop back up. And when you do the last you move the whole DR scale to capture more highlight range. This is what the Pentax/Canon call "highlight priority" (er.. highlight correction in Pentax). Sony allows the same.

With Olympus coming the E-30, they are doing this but other than setting the camera to ISO 100 (when available) you are stuck with very noisy shadows as the whole DR scale was prioritized for highlights at all times.

So I still don't understand how DXo doing it that way still fails to account for real world photographic DR we can use.

That's right. DxO just measures between a saturated sensor and an SNR of 0dB, so they get both shadow and highlight in one measurement - the choice of the grey point is arbitrary. The only problem is 0dB is just a bit too low to measure if our goal is to compare "usable" DR, as described above. When they started doing their measurements it was probably a non-issue, but now that we've got some incredibly low read noise sensors out there it is skewing the results in a way not practical to photographers.
Once again, that is indeed part of DR. I can tell you right now the K-5 has bags of shadow DR and I can shift it at will to get highlights, making it quite real world usable indeed.

DPReview has their studio shots, and they include a shadow box that is good for pushing to see how the shadow noise looks. The RAW files are downloadable. The problem is they really don't have a good highlight feature anywhere in the scene to make sure the camera hasn't just traded shadow range for highlight range. You can kind of get around this by verifying that the exposure was the same and then go look at DxO's ISO measurements for the cameras. Their ISO measurement is in fact just a measurement of the saturation level of the RAW file. By noting the exposures used in the DPR test and checking the DxO ISO measurement you can adjust how much you push the shadows for each camera for a "fair" comparison.
Well in general I have measured DR relative to other cameras my own way with several Olympus cameras (e-300, e-330, e-410, e-420, E-3, e-620) and other brands (LX3, LX5, K-5, Pentax Q) and the numbers that DXo has have pretty much always corresponded to a certain level of "where do these cameras stand" relative to each other's DR.

They don't, but they do have nearly the same saturation level (adjusted for sensor resolution differences) - by which I mean the maximum number of photons that can be collected before clipping. The measured ISO of the sensor relates to efficiency of course. However, if what we really want is nice clean mid-tones and the freedom to push and pull an exposure without noise showing up everywhere (not just the shadows) then we want to gather as many photons as possible so we will have the lowest photon shot noise. And this is set by the saturation level, which is just about the same for all the cameras (the GH1 is the odd man out here, slightly higher than the others but only by 1/3 of a stop).

Efficiency measures how fast "the well" fills up. Saturation measures how deep "the well" is. For best low ISO noise performance we want the deepest "well" possible but don't particularly care how fast it fills. For best high ISO performance our concerns are exactly the opposite - it could be a shallow well (we won't ever get to collect many photons anyway at high ISO) but we want it to fill efficiently.
Ken
Hmm ok.

- Raist
 

paparazzi666

New member
The expression of this thread OMG is very APT.
I grew up with an extensive line of Olympus OM cameras, as a student, the OM10. Then I got the OM2n, OM4, OM4Ti, OM3 and OM1n for nostalgia. I had all their famous lenses and motor-drives and their amazing flash system... loved it.
Now Oly have come out with this same LOOK and all of a sudden the Canikony LUMPS of dslr look dated... what a paradigm shift. Dont get me wrong cos I used the Canons and Nikons extensively too, both Film and Digital. But betting that an OM look is relevant today...WOW what a good bet. It's going to sell really well. The old pentaprism instead of darth vader's helmet for example... shouts MAN TOY. Getting this camera just for the LOOKS is a no-brainer. The fact it has 16mp, shoots high ISO 3 times better than an Ep2 and is going to be superbly competent is icing on the cake...hehe. Now my Olympus Ep2 with a small 25mm cmount f1.4 lens can be used as a travel/stealth outfit whilst the OM-D is for some serious shooting. My Ep2 is so battered its probably not worth selling it, plus it still works perfectly. Samples here.
Flickr: Please wait...
 

jonoslack

Active member
Thanks for that Amin
It Looks great doesn't it
definitely drool (I must not bite, I must not bite, I must not bite!)
all the best
 
V

Vivek

Guest
Finally, it appears that the "new sensor" in EM-5 is only 40% less noisy than the dated EP-3' s 12MP sensor.

=> GH-2 still rules.
 

kwalsh

New member
Finally, it appears that the "new sensor" in EM-5 is only 40% less noisy than the dated EP-3' s 12MP sensor.

=> GH-2 still rules.
Yeah, as somewhat useless as that quote was in my mind it confirms G3/GX1 sensor (which is fine by me, a whole lot better than the old 12MP sensor).

Ken
 

woodmancy

Subscriber Member
I'm a little surprised at the positive reaction to the looks of it, when so much criticism was dumped on the Panosonic G1 for the "faux" bump on the top. Can't get anymore "faux" than the OM bump - no prism in that prism housing!
It would be nice to get a real motor in that bolt-on battery grip, so it would remind us of film moving through this thing.
I admire Pentax's sentiments with the fresh modern K-01 design rather than this Oly OM rehash.

Keith
 

jonoslack

Active member
I admire Pentax's sentiments with the fresh modern K-01 design rather than this Oly OM rehash.

Keith
HI Keith
I reckon there's room for both . . . but I'm inclined to agree that the K-01 design is more innovative . . . . . . except that it doesn't have any kind of viewfinder option :eek: I just spent a week shooting in snowy mountains - the EVF of the NEX7 was bad enough (and no better than the Olympus VF2 in this case) - but the LCD was completely unseeable on any camera . . . which would mean pointing and hoping with the K-01!

I'm also not sure that 'rehash' is quite fair - it's got the references on the outside, but, like the modern mini, there's not much else in common. I think the back is rather stunning on the OMD as well (and of course, has nothing to do with an OM).
 
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