During the days of film, we use to go crazy over new high ISO film speeds. We would talk about pushing the film by a stop or two to see if the grains would hold up. Needless to say the question of High ISO has been long in the tooth but people seem to misunderstand the relevancy of such things in the Micro Four Thirds system.

When you go out to buy a camera, shooting at a high ISO is often the most important consideration. This should not be the case for more casual users who often shoot in daylight. Product segmentation has always been adopted by camera manufacturers to tell the difference between low end models and high end models. For the Micro Four Thirds system, the High end model is the Panasonic GH-1, and this is determined by the larger sensor used in this particular model.

Why sensor consideration is important is that manufacturers have a tendency to package each camera differently with optional or more features without really raising the bar of the sensor performance.

Price difference is small too, but final street price will depend on country

For example, let’s look at the two models in the entry level range, the GF1 and the EPL1. Both perform similarly as you can tell from the DXO lab report, there is a slight difference in low light handling and Dynamic Range. So if you are choosing a camera based on high ISO capability, you could of course take the Lumix over the Pen but the difference is negligible. This clearly points out that high ISO capability isn’t really going to differ that much if you are choosing one manufacturer over the other. So what manufacturers do is to package them with the sort of features you may wish to use. Another factor that is often overlooked is the use of in-camera stabilization. This will greatly affect the price of upgrades if you are thinking of owning more than one lens. Lenses which have built in motion stabilizers will cost more and this is a fact. Of course you can freely use Olympus and Panasonic lenses on both these systems but there are also slight differences. For example Panasonic has added CA (Chromatic Aberration) correction into its camera firmware (the software contained within the camera which gives it the functionality) to correct color fringing. This color fringing can be seen when you have subjects with very sharp color contrast. So this will be manifested if you use a Lumix lens on a Olympus Pen camera. But before you jump to any conclusions, let me assure you that it is not that bad. Often, these fringing will only appear when you start to blow up images to poster sized prints. Generally it is not noticeable in smaller prints or in web use.

Likewise, Lumix lenses with built-in stabilizers will not work on the Pen camera as such stabilizers will have to be triggered by camera firmware. Since all camera companies keep their firmware proprietary, there will not be a chance of gaining an extra two stops should you use a Lumix lens on a Pen body.

The use of such in-camera and in-lens stabilizers is another way to deal with the question of High ISO as shooting in low light situations such as building interiors or night scenes. For such scenes, the lowest allowable shutter speed will be sufficient to capture the ambience and character of a place without blurring the image when hand holding the camera However this type of stabilizing option is not a solution if you wish to freeze moving subjects in low light.

The right sensor will get things done in High ISO. This can only be the GH-1

A subject in motion needs a high shutter speed to capture or freeze motion, this cannot be done with a low shutter speed in low light. So if you are going to be shooting moving objects in low light, High ISO becomes very important. Compared here are the two cameras, the GH1 and the EP2, as you can see the EP2 is a notch below the GH-1 in terms of Dynamic range and Low Light handling. The Pen EP2 is still marginally better than the GF1 by comparison.

The fact is that sensors do matter and the GH1’s sensor says it all. All the rest, be it the EPL1, GF-1 and Pen EP2 are using the same sensor and the marginal difference among them is attributed to the firmware that pushes the camera a bit more. In recognizing this, any consideration for a High ISO must be compared with similar sensors for the best judge of performance. There is no point in judging the marginal difference between one camera to the other if they are using the same sensors. Furthermore from the indicative price, the EP2 is more expensive to own whereas the GH1, which is about a year old now, has come down significantly in price and is a great buy for the performance it offers. There are rumors of a GH-2 coming out but that said, the sensor will be the same as the GH-1. Personally I do not see much image performance enhancements in such cases but there will be a significant change in the amount of ease of use features like touch screen and navigation. That said, it may be an attractive consideration for casual users but serious amateurs will not fall for these as there is really no significant improvement in image quality.

What the hell is Dynamic Range (DR)? First, there is a French site, DXO Mark, which puts out DR readings using RAW files. Then you have the guys from DPreview.com who do this on their own measuring both RAW and JPEG output. If you are shooting only JPEGs, of course you should take note of the DPreview.com values. Professionals will always use RAW files as the benchmark for measurement.

Now Dynamic Range measured by the sensor’s ability to perceive and register light. Imagine this for a moment. Light is registered from bright white right right into the shadow areas and until it is completely black. The shades of grey in between Black and White is what you perceive as detail and this is specified in light values of EV. Clipping occurs when the sensor can no longer register any details as can be seen in area as pure white or pure black.

There are also differences in JPEG and RAW output in regard to Dynamic Range. For example, the Dynamic Range JPEG output for the Nikon D700 is really poor and rated below 8 EV but the RAW Dynamic Range is rated much higher with close to 4 EV improvement over the JPEG output.

In terms of Micro Four Thirds sensors, they are playing catch up to the APS-C sized sensors. Of course the new Sony E-system and Samsung NX will be in direct competition as well. The GH-1’s sensor will be on level ground with the APS-C (in the new Sony and Samsung models) as it is a different animal. Panasonic has a much bigger sensor installed on the GH-1 so one way to know where your model stands is to read in between the lines. Of course there is the “pricing” concern as the GH-1 is probably over rated for its asking price.

Comparing the Dynamic Range Performance on the GH-1 and GF-1

Dynamic range has always been a consideration even from the days of film. Those of you who have used slide will prefer this to say negative film as the former has more dynamic range than the latter.

In the Micro Four Thirds world, the issue now is which model should I choose to get better dynamic range. Well, this is a no brainer as the GH-1 will win hands down however if you wish to wait for this to be more affordable, then you probably will have to wait much longer. You see, developing a sensor cost millions of dollars and in order to recoup the R&D cost, the technology will have to be paid for in terms of units sold. This means that more products will have to carry this sensor before a new one makes its way into newer products.

Lastly, many of your would be asking what good is Dynamic Range good for. There is a simple answer for this, you get richer photos with more depth. This has to be seen to be believed as the visual details will be very rewarding. Sensors also register different dynamic ranges at different ISO settings, thus a picture shot on ISO200 will have different DR values to one shot at ISO1600.

All these details may complicate the image capture process but you only need to know which ISO setting is best for a particular camera for maximum Dynamic Range. For example, the Olympus Pen is most effectively used at ISO 200 if you are looking for the best image quality.

DR RAW files compared, souce: dpreview.com

The diagram shown here is a good example of what you are able to read from sources like DXO and DPreview.com. By looking at the highlight and shadow range, you will know how much detail you are able to capture in RAW. If you refer to the Olympus Pen, you’d see that it has better dynamic range in shadow areas than in the highlight areas. The Lumix G1 is compared here but these values can be applied to the G2 and GF-1 as they are all using the same sensor technology. The only difference between them is the features they have inbuilt into the camera package.