However, I discovered that we do have some sort for 'raw' file capability. That is to take picture at set at ISO100 (the lowest possible), choose Shutter priority, get the focus right, choose the right shutter speed for the object (inverse of focal length i.e. 1/30 at wide, 1/60 or 1/100 at zoom end of F30 for hand motion blur), and let the metering choose the aperture (usually max F2.8 in indoor shot). If there are bright light, then the metering will choose smaller apeture like F5 or even F8 - but you are ok for you are shooting with ISO 100 already.
notes: True Raw file is the data captured in the CCD before any processing by the camera. It contains 12 bit (some high end camera may have more bits) information for each pixel. The file in F30 has been converted into Jpeg format. In jpeg, there is only 8bit for each color pixel (or 255 levels).
Under in-door and low light condition, at ISO100, you will get quite a dark picture. But that is ok because you can use software to get the picture you want. That is what raw processing do ... software vs in-camera hardware processing built into the camera. Please note that due to under-exposure, the dynamic range is reduced and so you are loosing information and details. After post-processing, you get a more plastic looking nevertheless less noise photo... you loose textures.
Below is a series of different ISO photos taken - fixed at 1/30, F2.8. The correct exposure is 1/30 at ISO 1600. You will see at ISO 3200, the camera choice of F3.2 is over-exposed a little. At ISO 100, you could hardly see the photo.
However, by using software like PhotoBrush I can process the ISO100 photo with exposure +6EV, and then use Neat Image to remove the noise. The resulting photos vs the correctly exposed ISO 1600 is in fact slightly better! Slightly more details and with Neat Image more smooth.
However, expert in Fujifilm Forum pointed out the ISO1600 photo is a better picture with more details - look closer at the area surrounding the white spot of the bottle. You can see the reflections of the surrounding areas better. I was looking at the wording on the CDs which appeared clearer to me (that is because the dynamic shades have been lost with under-exposure resulting in flatter look and contrasting look and appear better when just looking at letters). Saying it another way, loss of colors range due to under-exposure will give a flatter and more plastic looking photo after processing (there is lost of textures).
Similar result is obtained by using Picasa2 choose "I'm feeling Lucky" button or in FinePix Viewer choosing Auto Adjust. The procoessed ISO photos are shown below. Even with just Piscasa one-step processing, the photo turned up to quite nice. ... rich in color and low noise!
I have tried this same thing on my Panasonic FZ3 (3Mp) camera. Under expose at 1/30 ISO400 and 1/8 correct exposure (FZ3 has image stabilisation) and obtain similar result ... software correct an under-exposed picture is good!
I took the above shots was for comparison with F30 for noise processing - image stabilization vs high ISO capability. Forgetting about the difference in size 6M vs 3M and just look at noise. F30 wins.( Comparing F30 ISO1600 vs FZ3 1/8 more light exposed ISO400).
Comparing ISO 3200, 1600, 100+6EV after Neat Image default is shown below. Please not it is not fair to ISO3200 as the metering overexposed the image. The ISO100+6EV could even be brightened a little to compare with the ISO 1600 shot.
This series of test was conducted to see if we could do better than the camera use of ISO3200 under low-light conditions. The answer seemed to be yes but need your own software post-processing. With software like Picasa, the post-processing is not that much time consuming or difficult. So, we could use ISO400(Auto) for a good balance between ready-made and post-processing effort and get better than ISO3200 photos. Will be trying this for real world low light photos to see if this works out well. ... try to use the highest possible ISO to minimize loss of colors details due to under-exposure.
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