Sounds very much like Samsung's "micro dimming".

Similar to local dimming but Samsung don't actually dim the LED'S but artificially tries to create a similar effect by controlling the contrast in different areas of the screen.

As far as I know it can only be switched off via the service menu.

Sets with micro dimming also have CE Dimming, this does dim the LED's, apparently this can not be switched off in the service menu, but I have come across some sites that say it can.

Movie mode gives you the fewest picture enhancing options, it is the mode that makes the picture closest to what the director intended. 'Standard' mode has lots of picture enhancing turned on. Also make sure 'Cinema black' (if your model has that) is either off or low.

Sounds like CE Dimming to me - my samsung plasma used to have it's own version of this where the Auto Brightness Limiter kicked in with dark scenes and the brightness would adjust up then back down. Some see it and some don't it seems ...

This post on avforums may help you:
http://www.avforums.com/threads/sams...mming.1700774/

i'll try movie mode, but i'm not convinced.
the image looks a little washed out in that mode.

movie mode totally unacceptable.
colours are so washed out and dull.
nowhere near being close to what the "director intended".
blues were almost grey.

As did mine at first (i use movie mode for my SD channels), but after setting it up, it looks fine now.

by that i assume you don't use movie mode for HD channels?
and what do you mean by "setting it up"? i assume you don't simply mean turning on movie mode, unless you like all your colours washed out.

No i don't use it for the HD channels, i just use the Standard Mode for those, as looks better for the HD for me.

I don't mean just turning on Movie Mode, no, as the default settings are rubbish tbh, looked like i was watching a bad pirate film, i went through a big thread of different picture settings over on the AV forums, found a one that wasnt to bad, and just slightly tweaked it to my preference.

You may find the following of interest.....

http://www.hdtvtest.co.uk/news/samsu...1107121282.htm

Majority of reviews generally find movie/cinema mode the closest to a fully calibrated TV - and it is often said that viewers often remark on the colours looking a little dull after calibration, one reason for this is because they have been used to the colour being set far too high.

If you are wanting reference picture quality you can have it calibrated professionally or do it yourself with Spyder4tv if you are confident with the service menu of your TV.

If you don't want to spend this kind of money there are dvd/bluray calibration discs which do a pretty good job.

http://www.amazon.co.uk/Digital-Vide.../dp/B00009WW03
http://www.ebay.co.uk/itm/like/16135...13=80&ff14=108

surely these calibration tools are only usefull if you can fully disable all the functions that the TV does to make the picture "picture". and if i could do that i wouldn't need the tool as i could disable them in the first place.

problem is there appears to be no way to disable this dimming "feature".

There usually is a way of turning off CE Dimming with samsung's via the engineers menu which can only be accessed via a specific code. The only problem being is that if you change the wrong thing you can knacker up the TV.

Having a look around I came accross this which claims to improve things which you could give a try.

Reviewers carry out full calibrations on various TV's, many with features similar to this dimming feature that can not be disabled, they still get near perfect settings for greyscale/colour temperatures, RGB settings, white balance etc etc.

In the case of the Samsung they will have disabled all digital enhancements, of course they could not disable the auto dimming but that didn't have a direct impact on the calibration, just on playback, but was regarded as a minor shortcoming. You should be able to get reference picture quality out of this TV, especially with a full calibration, even HD basics will get you close enough.

Re dimming - does your TV have a "shadow detail" feature, if it does try +2, some say it helps.

i've tried many codes to get into the service menu, but none worked for this model of samsung

the default is -2 i believe, i have since changed that to 0.

what are you starting from though?
as there are many other settings that you haven't mentioned.

I've edited it as it wasn't the full thing, have another look

This is what's required to access my service menu, have you tried this one?

yeah that works, but pressing 0000 when on advanced does nothing.

As far as I can work out this is not CE dimming where the TV dims the LED's, it sounds like micro dimming where the TV adjusts the contrast, but all accounts it can be disabled on certain models, unfortunately not on this model according to the review by hdtvtest, they say it's undefeatable.

Movie mode is the only way to disable it, well it is on my Samsung Tv, or you could also try upping the brightness, as i did read somewhere, that when you put it to a certain number (think it was in the 50s) in the other modes, that can also disable it.

except it doesn't disable it on mine.

These are my Movie Settings, which i use for SD :-

Picture Mode: Movie
Backlight: 8
Contrast: 85
Brightness: 44
Sharpness: 18
Color: 50
Tint: 50/50

ADVANCED SETTINGS
Dynamic Contrast: Off
Black Tone: Off
Flesh Tone: 0

Color Space: Custom
Red: 47, 0, 0
Green: 5, 47. 5
Blue: 0, 8, 45
Yellow: 51, 48, 3
Cyan: 3, 49, 54
Magenta: 43, 6, 44

White Balance: 27 25 21 41 50 30

10p White Balance (interval, r, g, b)
1 0 1 2
2 0 0 0
3 1 0 0
4 1 0 0
5 1 0 -1
6 1 0 -1
7 1, 1, 0
8 0 0 0
9 2 1 2
10 0 0 3

Gamma: +0
Black Enhancer: Off

PICTURE OPTIONS
Color Tone: Warm2
Noise Filters: Auto
HDMI Black Level: Normal
Film Mode: Off
Auto Motion Plus: Clear
LED Motion Plus: Off

i'm not going to use different modes for SD and HD though.
that would just be silly.

Buy a better TV!

Works fine for me