There were three issues that concerned me… under-exposure, loss of detail/resolution, and an inaccurate colour-cast.
There’s also the matter of the large file sizes. Though that’s not really an issue… more of an inconvenience that’ll no longer be a problem once I’ve increased the RAM on my computer.

Taking them in order then:

Under-exposure

This could well be a lens issue and as such I’m not letting myself get too concerned by it until after I’ve tried some shots with a different lens. Its also conceivable that in part its a side-effect of the colour-balance issue, though I doubt it. In any event its fairly easily remedied, either pre- or post- shot, so can hardly be called an “issue” so much as a “quirk”.

Loss of Detail

This was of much greater concern, and the source of much of my initial disappointment.
Of course, this too could have been a lens issue, but equally as well may not have been. And if not, then not so easily remedied. In fact, if a sensor- or processor-related problem then I doubt if it could be remedied at all short of a firmware upgrade maybe. Hence my concern.

However, that impression was formed on the basis of the dozen or so pics I shot with the camera virtually straight out the box (just couldn’t wait, could I?) and conceivably I hadn’t paid quite as much attention either to the settings or in actually taking the shots as I should have done.
And when I inspected the track and river shots I’d done, aside from the persistent colour issue I was much more satisfied.

I subsequently sent one of the RAW files from the river set to a mate for closer scrutiny by a much more experienced eye than mine, and his opinion was, to quote “the GX20 has sort of a clarity that is intriguing, its the detail in the images that is clear and the file looks neat in appearance, think if the white balance is sussed it will be bloody good too”, which really does sum it up quite nicely.
And that’s with the bog-standard lens that came with the camera!

So I think the “loss of detail issue” isn’t an issue after all and can be confidently forgotten.

But there still remains…

Colour Cast

This is clearly a white balance problem and, after looking closely at all the shots, plus taking on board the various comments made about the pics I’d posted to Flickr (which drew attention to either a pink or a purple tone in the shots) I began to suspect (and eventually confirmed to my satisfaction) a problem with the magenta.

With a lot of tinkering in post-processing its possible that the colour can be corrected, but that would inevitably entail a helluva lot of work on each individual image just in getting them to look as they should look. And I’m not at all convinced that configuring a camera-specific preset in Lightroom (my RAW editing app of choice) to do all this work on image import would necessarily be effective for every image taken under a wide range of circumstances.
Now I’m not totally opposed to enhancing a particular colour or manipulating the colour balance at post-processing stage, providing I’m starting out with an image that provides a fairly accurate colour balance! Absent that and one is no longer looking at an artistic interpretation (hmm… please forget I just used the word “artistic”. Don’t know what came over me for a moment there!) but at a flawed image. Not good!

Curiously, this matter of colour balance also seems to be exhibited by the other cameras (blue with the GX10, yellow with the 400D), but nowhere near to the same extent and not with every shot. In other words, the anomalies are at a reasonably acceptable level, and not every pic merits tweaking.

However, it was suggested to me that maybe the problem’s not with the camera itself but with the way its writing RAW files, especially if the version of firmware its using to do this is different to that of the GX10 (which it is).
So two ideas came out of this… either use the RAW conversion software that comes with the camera (which I don’t), or make sure I’ve got the latest stable version of Lightroom (which I hadn’t).

Now, I’ve got the RAW converter app that came with the GX10 installed though I never use it, preferring instead to use Lightroom. So I’d not bothered to install the later version with the GX20, not even having considered using it.
However, I uninstalled the GX10 version then installed the later version… and whaddya know? The shots look fine! (Curiously, they also load a damn sight quicker than with Lightroom.) Not even a hint of colour imbalance.

Feeling a tad more optimistic, I set to thinking… So if its the way the data’s being read as opposed to a flaw in the camera itself (or indeed in its settings), then maybe upgrading to the latest version of Lightroom might render a similar result.
And that’s what I did.

Hmm. Well, Lightroom continued to render the files with a magenta tone bias in the white balance (confirming my original diagnosis at least)… but this time showing that in the control panel as a +10 increase. Which it hadn’t been doing before… or at least, not that I’d noticed.
Knocking that +10 off (to effective 0) I exported some test JPEGs. They were definitely an improvement but, alas, not quite enough. However, this does suggest that if I want to persist in using Lightroom for processing the GX20 files (which is my preferred option) then at least I can overcome the problem relatively easily simply by setting the tone slider for that colour spectrum in the opposite direction.

Whoopee!

But another couple of possibilities emerge from this.

It looks as though, if I use the Samsung-supplied RAW converter I may well be able to see the files rendered as they should without any additional tweaking on my part. And if that’s the case, that further suggests that processing done in-camera will probably be okay, meaning that JPEGs should come straight off-camera fine.

Which of course needs testing. And if that’s the case, then maybe I could use the GX20 principally for shooting JPEGs, reverting to RAW only on really critical shots or where I anticipate a lot of post-processing. (In other words, use it as my main “events” camera.)

Now this may seem a bit of a bizarre approach for using a dSLR, but it does actually have certain merits.
For example, when I did the Carnival Against the Arms Trade shoot in Brighton earlier this year the folk down there were eager to grab some pics urgently (practically straight off-camera) in order to send out to various media (who were squawking for photos) in virtual real-time.
Yet that presented horrendous problems as they simply weren’t geared up to handle RAWs, and neither did they, or I, have the right connector to simply process in-camera and then plug the GX10 into their computer. Nor, weirdly, did they have a card-reader on hand (neither, stupidly, did I!). We came up with a work-around eventually but by that time they’d grabbed initial shots from someone else so I missed out on what could have been a really super opportunity.

Shooting in JPEG (plus carrying a card-reader of course!) would have sorted that problem. In fact, the problem would never have arisen.

(Memo to self… in future be sure to carry a card reader and PC connection cables for both cameras whenever attending an event. I don’t call myself an idiot for nothing y’know!)

Then there’s the matter of the file sizes. Were I to shoot principally in JPEG I wouldn’t have to invest in a lot of new high-capacity cards, nor would I be stretching computer resources to their limits if/when importing the files into Lightroom.

At best this is only a partial solution for it’d only really be relevant to my “events stuff”. Where my “scenic” shots are concerned I think I’d still want to shoot RAW, preferring the much greater flexibility in processing, and quality-retention, that such allows.

Nevertheless, things are looking a lot more hopeful now.

In conclusion then, I have to ask myself how I feel about the camera now.
I won’t claim to be ecstatic. And I’m still mildly disappointed by not having experienced that joy of playing with a new toy that I feel I should have experienced. In that sense, I feel somewhat cheated.

But at least now I don’t have the inclination to chuck the bloody thing straight back to the place from whence it came. In fact, if my mate’s assessment bears out, then the thing will prove to have been a worthwhile acquisition.
And you can be assured, now I’ve started this particular topic I’ll be posting news of later developments.

Well, that’ll be something to look forward to, now won’t it? (Heh heh)