[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] mms6:
Definitely not an limitation of the manufacturing process.. My first-gen Samsung Captivate's screen blacks are actually deeper than the my Galaxy S3 with maximum brightness, displaying the same completely black #000000 screen in a completely dark bedroom at night...

Also what I have realized is that on my Captivate's screen, it do not has any of the stains or the dots on it when viewed in a dark room.. It has a little bit of "banding" problem on the top portion of the screen, but it is less noticeable than the stains and especially the "black dots" effect...

I have the EXACTLY same problem with my PS Vita similar to my Galaxy S3, but the PS Vita has much more stains than dots than the GS3 (more imperfection) although the PS Vita is lower resolution, and slightly bigger screen. The PS Vita uses the Samsung Super AMOLED Advanced (pentile matrix)...

Also, the screen production is not consistent on the GS3. My first GS3 has Wi-Fi random disconnection issues, so I exchanged it under the 15 days policy from Rogers, for another GS3.. The original GS3 has a lot of "black dots" (approx around 15 or so) and slightly stained on the top right corner.. The exchanged GS3 was slightly better and had no stain marks and only a few black dots and a slight pink spot (when viewed on white #FFFFFF).. Also I had to exchange my second one back to the store because my battery cover had some hairline cracks within a week of usage or so..

The THIRD AND FINAL GS3 I received did not have any stains, but suffered a more severe "black dot" effect (approx. 15-20 dots).. But my Wi-Fi issue was fine, and there are no pink spots, so I have been using it until now and did not really bother an exchange....

If you are extremely lucky, you might get a "perfect" or "near perfect" AMOLED in the current generation... But still the QA is going down the toilet when compared to my First Phone with Super AMOLED, my Samsung Wave S8500 (the screen was PERFECT on this one, NO stains/dots/smudges etc...)

Samsung is cutting costs and lowering QA because it is fulfilling more AMOLEDs for other manufacturers such as themselves (its is not just the top of the line Galaxy S# series using AMOLED, mid-end and some lower ends Galaxy series are using AMOLED as well) Also Samsung has to supply for Motorola, HTC (fewer models though), Sony (only for PS Vita), Fujitsu (for the Japanese Keitai smartphone from KDDI and Docomo) and so on.....

Now all this happened in quite short period of time, Japanese keitais with OLEDs came on the market last year... Samsung Wave came onto the market in 2010, there is only a 1 - 1.5 years in between here... The demand exponentially increased as smartphone sales went up, and more manufacturers are contracting Samsung to build OLEDs..

Personally, I do not think the process of making OLEDs have improved....

THE ONLY area it might have improved is probably the PRINTING... Printing higher resolutions has allowed Samsung to increase the pixel density and decreasing the subpixels (and this is probably why the Super AMOLED HD screens are dimmer than the original Super AMOLEDs at the same maximum brightness)

That is all I can say for now...

Live with the miniscule defects such as stains, dots, smudges etc on your OLEDs.... These problems are minor issues anyways since you have to be in a very dark environment with almost complete black #000000 image to be able to pick up the "defects".... Wait for a few more generations and allow the manufacturing process to improve more and still be able to fulfill Samsung's own demands and contracted demands for other manufacturers..... (Or other companies might finally bring more and more of their own technologies in OLED to the consumer masses)...

END OF RANTS...

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