Hello all, between myself and some others on this forum, namely @Built To Chill @Mattjax05 , we have pieced together what the different settings do and how different combinations affect different content.*Note that these results were obtained from tests on the XF90 & A1 Oled models. Both of these use the X1 Extreme chipset. It it reasonable to assume that other TV's which also contain the X1 Extreme chip will behave the same, except for the cases where TVs do NOT include X-motion clarity - these sets should just have clearness 0 the whole time. There is a possibility that these settings work differently on different chipsets other then the X1 Extreme.24p source -->Motionflow Off, True Cinema or Custom w/ Smoothness 0; with Film mode Off = Correct 5:5 pulldown cadence.Motionflow Off, True Cinema or Custom w/ Smoothness 0; with Film mode High = Correct 5:5 pulldown cadence.Motionflow Off, True Cinema or Custom w/ Smoothness 0; with Film mode Low or Medium as yet untested, however I believe they would also result in the correct cadence.24p over 60hz source -->Motionflow Off, True Cinema or Custom w/ Smoothness 0; with Film mode Off = 2:3 pulldown cadence.Motionflow Off, True Cinema or Custom w/ Smoothness 0; with Film mode Low = 2:3 pulldown cadence.Motionflow Off; with Film mode Medium = 2:3 pulldown cadence.Motionflow Off; with Film mode High = 2:3 pulldown cadence.Motionflow True Cinema or Custom w/ Smoothness 0; with Film mode Medium = Correct 5:5 pulldown cadence.Motionflow True Cinema or Custom w/ Smoothness 0; with Film mode High = Correct 5:5 pulldown cadence.24p content delivered by UK broadcasters -->In the UK SD and HD tv is delivered at 25fps over a 50hz signal. For some content this is a 50 fields per second interlaced source (where 1 interlaced field is half of a full frame), and other content a 25 frames per second progressive source where each frame is shown twice in the 50hz broadcast signal.24p content is sped up by approx. 4% to 25p and the pitch of the sound corrected. Therefore when broadcast there is no frame rate mismatch.Motion Smoothing and the Soap Opera Effect (soe) -->Motionflow Custom, Smoothness above 0; Film mode Off = Smoothing but NOT interpolation - possibly frame blending.Motionflow Custom, Smoothness above 0; Film mode Low = Smoothing via interpolation for 24hz source signal - causes noticeable SOE if Smoothness is 2 or higher.Motionflow Custom, Smoothness above 0; Film mode Medium = Smoothing via interpolation for all progressive source content - causes noticeable SOE if Smoothness is 2 or higher..Motionflow Custom, Smoothness above 0; Film mode High = Smoothing via interpolation for all interlaced AND progressive source content - causes noticeable SOE if Smoothness is set to 2 or higher.A word on the Clearness setting -->This is Sony's implementation of Black Frame Insertion (bfi). On the X900F & XG9505 models (or any subsequent model which is released which includes X-motion Clarity), setting Clearness to 1 will engage the X-motion clarity technology. This works really well and I actually have this set for all of my content. All this does is reduce motion blur, which is itself caused as a result of the sample and hold method that lcd displays use. There is no smoothing or interpolation applied by this setting.A word on Film mode Low -->Film mode Low appears to engage smoothing via interpolation only for a 24hz source signal, therefore obviously for 24p content.I hope that I have explained clearly what the different settings and combinations do. I hope that people find this useful and it helps them to achieve an image that they are happy with. If people who have different chipsets notice that their tvs behave differently, please comment below so we can get it documented.*Latest update on final conclusions - 19th April 2020*There have been several firmware updates to the XF90 since release and the update to Android 8 change subtly how some of the motion processing was working. Based over several months of tweaking and testing with different content, I have arrived at the follow optimum settings and why I think so.When Motionflow & Film mode are NOT Off, Film mode appears to be trying to constantly track the frame rate of the source content that is being displayed (so that it can decide if it needs to do anything with it or not). I have noticed that when the source is 25 or 50 fps (which tend to always come in a 50hz refresh rate wrapper), that every now and then Film mode can 'lose lock' (for lack of a better phrase) which can result in a random frame stutter every now and again. My theory is that sometimes it slips up and thinks the 25 fps source is actually 24 fps, so then it tries to perform reverse pulldown causing the glitch. Obviously for people that notice this it can be quite annoying. However this links with what I am going to say next.Many people actually want to view their content with a little bit of smoothing in order to remove the natural STUTTER that comes with low frame rate content. Everyone wants to view their content without JUDDER. The tricky part is balancing the correct level of smoothness to reduce stutter but not cause SOE. Due to this I would advocate using an external streaming device where possible which has the features to be able to match content based on source frame rate and dynamic range. In my personal case I have an Apple TV 4K. I have it set to 4K SDR 50 hz by default with match content enabled for both frame rate and dynamic range. What this means is that if I start watching something that is 24p Dolby Vision, the Apple TV 4K will change its output refresh rate to 24hz to exactly match the source frame rate.The two different settings I mainly use on the XF90 are as follows:When the source frame rate exactly matches the refresh rate, set Film mode to Off, Motionflow to Custom and use Smoothness 3, Clearness 1.When the source frame rate is 24p but the refresh rate of the device is 60hz e.g. Native TV apps Netflix, Prime Video, Disney+, Youtube etc, set Film mode to High, Motionflow to Custom and use Smoothness 1, Clearness 1.Of course please be aware that this is what I think looks best on balance to my eyes on my TV set. To others they may prefer other options. However you should now be armed with the information to be able to achieve what looks best to each of you individually.People with a TV containing the X1 Ultimate processor should be aware it has taken away the option for Film mode Low/Medium/High. It is simply Off or Auto. Therefore like on the XF90, if you can get content frame rate to match refresh rate then leave Film mode Off. Otherwise if using Native apps, or if you explicitly want to achieve a strong SOE effect, should always leave Film mode on Auto on TV models with this chip.Thanks for reading