I have just followed from your edit exchange on the article Blu Ray Disc to find the exchange above Sadly you appear to know little about the subject and to be fair it has become confusing because much of the terminology has become abused First European Blu Ray discs are not produced in 24p format That is almost exclusively the preserve of the American regions Secondly the Blu Ray format does not support the proper 1080 progressive high definition formats 1080 50p and 1080 60p and I include the 59 95p in that This is because the data rate is not fast enough for these formats The European sourced discs that state 1080p on the packaging are discs produced from film originated material and is one of the abuses of the term progressive The term progressive strictly defines a video format where the lines of video information are recorded in strict numerical order 1 2 3 4 5 1078 1079 1080 Alternatively there is the interlaced format which displays the odd lines ony first odd field and then follows them by the even lines even field You probably know this already 1 3 5 7 1077 1079 2 4 6 1078 1080 They are actually stored in the digital video frame the other way around due to the digital video format s origins in the NTSC world In true video source material the even field displays a time slice that is 20 milliseconds later than the odd field and the two together give a comlete video frame This is also largely true in the Americas except the even field precedes the odd field by 16 6 miliiseconds There is a largish group of enthusiasts if that s the right word who have become somewhat anally retentive over the progressive video formats and who have convinced themselves that progressive is the only way to go The reality is that any improvement in the visual perception of the video is marginal at best and certainly not worth the doubling of the required digital data to support it But for them everything has to be progressive I shall coin the word progressivists for this discussion When film originated material is transferred to video in Europe the film is run slightly fast by 4 which allows one film frame to occupy both the the odd and even fields of the video frame known as 2 2 pulldown Thus the even field displays a time slice that is 0 milliseconds later than the odd field In order to satisfy the progressivists the Blu Ray producers state that such material is in 1080p format but using something called a Progressive Segmented Frame technique though they don t mention that last bit on the box That is that it is progressive video but the odd lines have been recorded together and then they are followed by the even lines It is really interlaced video but by the time the display device or the Blu ray player has de interlaced the video it doesn t matter one jot where it actually happens the result is perceptually indistinguishable from true 1080 25p video assuming the deinterlacing algorithm works properly If watched on a CRT display then of course the video will be interlaced as there is no deinterlacing prior to display but with that number of lines no one is likely to notice unless they sit inches away from the screen The description 1080p on the box is technically at least wrong but percetually the same as 1080 25p video The 4 speed up goes completely un noticed especially these days when the sound is adjusted back to the original pitch and obviously you hadn t noticed it yourself if you had convinced yourself that you were watching films at the original speed Once we cross to the Americas different problems occur Obviously running the film at 30 frames per second is not an option so instead film is converted to video by storing the same film frame on 3 half video frames followed by storing the next frame on 2 half video frames and then repeating 3 2 3 2 Thus 4 film frames occupy 5 video frames the technique is 3 2 pulldown often wrongly called 2 3 pulldown Properly deinterlaced such material is perfectly watchable and the viewer unlikely to feel anything is wrong But the progressivists have decided that it is not the way to watch film material and have even invented faults to justify a move to a progressive format I have even seen claims obviously failing to understand the technique that movement in the resultant video is uneven in that it jumps 50 further every other jump due to the 3 half fields The result was the 24p format The only problem with the 24p format is that if you try to watch it on a CRT display and A CRT is still unbeatable for contrast and colour reproduction the result will be unviewable to bad flicker something that was known as long ag