Hi,
I love that FCamera can give me access to RAW, but to be honest when compared to the output the default camera is still better. Please allow me to clarify, the FCamera DNGs have better resolution, but the default N900 camera gives better color output, more even and realistic.

Here's the deal. Yesterday I profiled my N900 using my Colorchecker passport and I loaded the N900 color profile into Lightroom and no matter what, I am unable to get the same even color across the frame color just seems to be off.

a) Vignette - FCamera images are darker around the edges but this can be resolved in LR
b) Blue / Green noise in shadows - I know part of the shadow issue has to do with color balance in the shadows, but not all dark areas should look green/blu-ish. Some shadows have uneven tones. I've tried split toning, adjusting shadow color in the camera calibration, white balance and I am not able to get even color. What is interesting is that the vignetting isn't just dark but also creates the same unnatural color variation in the vignette so even though I can compensate for the vignette I am unable to get even color throughout the image.
c) Exposure - FCamera slightly underexposes. IT's great because there is less likelihood of channels clipping but it if I wanted to expose just a bit bright, it is impossible to do unless I go to Manual and when outdoors in daylight, it is impossible for me to tell from the LCD if I have proper exposure. If there was a way to set +1/3 or +1 ev, that'd be great. As is, guessing when you're outdoors is not the best way to go.

So I guess here's my question. Is it possible for FCamera to output the image AFTER Nokia has processed the image (dark frame subtraction, color adjustment, tone curve) but before it gets written to JPEG? If you can do that that would make a huge difference to image quality

For those that say then that's not real RAW, I beg to differ, all DSLR's today do some of these same adjustments before writing to RAW.

khrm, are you comparing an api to an app?!? (you are referring to fcamera aren't you?!?)

obivously you don't know much about philosophy for working with raw images too.

so yes. for an average user camera-ui (stock app) is much better.

You're right. I've adjusted the original post to reflect that.

No, I do understand it's just an API and I do understand the philosophy behind RAW. If you can get edit FCamera output to match the stock camera, in terms of color, I would love to know the trick.

Having said that, read the last part of my question. All cameras, whether it be Nokia, Canon, Nikon, Olympus and etc all do processing on their image to get the most out of noisy sensors. Most will have some level of noise reduction via dark frame subtraction and etc.

My question was if it would be possible to output after Nokia has accounted for lens and sensor characteristics. It would still be considered RAW because you're outputting before converting to JPEG, before you apply a tone curve and map to particular colors. Folks that do HDR / Lowlight and etc can still do what they do on top of this type of RAW.

Same here, anyone got any pointers?

you are climbing into a tree with your butt first. (and you don't really understand raws that well).

only thing missing from you are the right parameters for the raw file. workflow is following:

1. raw file is captured
2. parameters are set
3. conversion
4. image file you can see with your raw viewer, image viewer, you name it.

the raw file is just a bunch of bytes with values from 0 to 254 from each sensing instance. it isn't a image file but with appropriate viewer that creates the parameters by itself you can look at it. those viewers preferably read the camera settings from raw data and use those as default settings. there are no camera settings for n900's module available I'd quess...


so only thing you would need is number 2. from nokia (or from sensor module manufacturer?).

e: the raw file is exactly the same that default camera app gets and converts it to image you can see.

I'm also very interested in things geohsia had noted, especially this damn bluish vignetting I couldn't beat with photoshop no matter how hard I tried (only desaturating aquas, blues and green did the job, but this way there's no point in it 'cause vignetted area looks b&w-ish).

jaimex2, you seem to understand pretty well the cause of this problem so can you explain a bit about this "2. parameters are set" point? Has it something to do with "Embedded camera profile" thing that protoshop displays in ACR's camera calibration tab? So can it be just tweaked through some DNG Profile Editor or am I not getting something right?

From my experience: the problem lies only in red channel which IS vignetted much more than blue or green channel. Not only frame borders are darker, but they in some places have "zero values" which means that those pixels cannot be tweaked anyway - they are already just black. But - default camera app's red channel looks pretty equal all around the frame. How could this be if it came out from the same source? And investigating carefully default camera's jpeg - I don't see any problem with colors on edges

IMO, i think there is an issue caused by the metallic frame around the camera.... i remember last year some guy here reported that he got better results when removing the back cover, he also tried painted the metallic frame but did not made a difference... the other thing is in my old n95, i got better quality pictures then i do with the n900 and camera is exactly the same... could the outside frame around the camera be causing the poor quality pictures?

What does this have to do with development? Can someone move this thread please. Thanks.

Does anyone know if it's possible for the N900 to create RAW files with greater than 8 bits per channel?

That would go a very long way toward making the images produced by FCamera more useful from a post-processing standpoint.. as they are now, they really don't offer the same editability as 'conventional' RAW files.

errrrr.... raw file is raw file. it is all you can get. it has everything the sensor has outputted when read.