this is bbc news. we'll have the headlines and all of them main news stories for you at the top of the hour — straight after this programme. this week, we're going low and slooow. although what is it that has given spencer such a shock? ow! tittering. an absolute pleasure and privilege to meet you, sir. how are you doing?

life beyond the grave, jim, but not as we know it. william shatner�*s got plans to keep talking after he's boldly on. this interview is the best thing i've ever done! - oh, for goodness' sake! laughs. and how can your foot flaunt the perfect fit? get ready for the science of stilettos. here's something that's hard to get your head around. more and more tourist attractions are clocking how important social media is in getting their name out there. yeah, we're at the new twist museum in central london, which is filled with a multitude of mirrors and instagrammable illusions that will play with your perceptions. oh, this makes a change — look at you down there! i know — and for reference, this is our true social standing that you're looking at right now. and what's weird is this isn't even the strangest thing i've filmed recently.

it is a fundamental law of the universe that nearly everything looks better in slow—mo — something that the the slow mo guys have been proving since 2010. three, two, one, go! their 1a million youtube subscribers regularly watch gav and dan slow things down as they blow things up. no—one stand in front of the cannon for obvious reasons. dan is ex—military and weapons trained, which means he can do this sort of thing. you, on the other hand, can't. and today, i've come to gav�*s studio in texas to add to the list of silly things that he's filmed in speaks slowly slow motion. yeah, this is either stuff that we're about to film with or just leftover stuff that we've already done. like, that's what's left of a newton's cradle

after dan shot it. i like the one that stayed on — it's quite nice. spencer chuckles. this is probably 500 mousetraps. this is when you threw dan into these mousetraps? yes. they way they all just sort of triggered from the outside inwards, just amazing — and that was all within, you know, a few milliseconds when that happened. right, here comes the science bit. now, whereas normal video cameras record something like 25 still images orframes per second, gav uses cameras that capture thousands per second. if you play these back at 25 frames per second, that's where you get your slow—mo. they have filmed at over! million frames per second and at that speed, they only have enough storage space to capture two seconds. so, how do you make sure it's the right two seconds? that's actually one of the incredible difficulties when high—speed was on film because you have like 1000 feet of film and if you press go, it's gone in, like, seven seconds. so, if something's going

to happen and you don't quite know when, very difficult to get that. hence, slow—mo has only really been accessible to the industry on digital cameras. now, these continually record over their own footage and instead of a start button, you get a stop button. instead of trying to predict when the things gonna happen and hitting startjust before, when the thing happens, you hit stop and you get to keep the last few seconds. that's actually the most stressful part of it, is, "i hope i don't miss the beginning by waiting too long and i hope i don't trigger too early". so, for example, if there's an explosion, you want have everything land but you don't want to wait too long that you miss the beginning of the explosion. yeah, yeah. these days, even phones can shoot at 1000 frames a second for only a fraction of a second. yes. so, what would your tips be for what works well in slow—mo and what you need to think about when you're trying to set up a slow—mo shot? if you can shoot 1000 frames per second on your phone, just point at everything. spencer laughs. i love anything with liquid.

like, a water balloon is the classic subject — it's what everyone does first — but i still find it fascinating that you pop a water balloon, the rubber whips out of there almost immediately, even in slow—mo, and then, you're just left with the shape — you're left with a big glob of water. i think the most important thing for shooting slow—mo, especially when you're getting towards 1000, is you need the right light and you need lots of it. so, for example, under a regular incandescent light bulb orjust like a lamp that you might find at home, chances are you're gonna see the flicker rate of the electrical grid and it looks really unattractive in slow—mo, it's really distracting to see all the lights doing this. yeah. so, shoot outdoors under the sun — the sun doesn't flicker — or get massive lights like i've got, which is the more expensive option. laughs. right then. time to make my own slow—mo. and in order to get some precision moves at high speed, we're attaching the 2000 frames per second phantom camera to one another high—speed

device that gav has recently got hold of. 0k! laughs. this is bolt. it's a high—speed robotic arm that's popular with movie—makers — firstly because you can mount any camera that you like onto the end of it, secondly because it's really fast. it's also motion—controlled, which means that you can repeat the same move precisely over and over again for multiple different takes. and finally, you can design of the move of the camera in your 3d previsualisation software and then import it straight into this and it'll execute it for you. and it says when the red light comes on, get out of the way. beep! gav sets up the robot by plotting some key frames in virtual 3d space. the robot control software can even be made to trigger physical devices at different times, which means things can be dropped partway through the camera move. today, though, we are using luck — sorry, judgement — and practice to try to follow

an out—of—date egg as it falls all the way down onto the floor. which it doesn't hit because i'm in the way. go. 0w. tittering. egg on face — no, the metaphor is not lost on me, thank you. but after spending a day being a guest slow—mo guy, i have learned this — you don't always need elaborate stunts to make great slow—mo. sometimes, your best prop is right under your nose. blows air through closed lips. laughs. pretty good from what i saw. thank you! laughter. it almost looks as though, like... laughter continues. i've filmed this a few times on a few different people

and this one is just really good for some reason. i am going to remember that image for the rest of my life. and interestingly, that's not the last we've seen of gav, either — he's gonna be back in a couple of weeks' time to help us film something very cool in slow—mo. cooler than that? surely not? even cooler than that. anything to forget that. our next story, though, is about preserving memories — those of our loved ones, particularly our elderly relatives. yeah, and someone who has his fair share of stories to tell and wants to make sure they live on forever is hollywood legend william shatner, and nick kwek went to meet him ahead of his 92nd birthday. los angeles — the city of angels, where everyone wants to get in front of the camera. camera shutter clicks. welcome to the storyfile studio. 0h, check this out! this start—up in the heart of hollywood will give you that opportunity. it'll record your entire life story. get in the hot seat. ok, here we go. here, customers are asked

hundreds, sometimes thousands, of questions over several hours and even several days. hairand make—up, of course. we're in hollywood. we have to have that. nick laughs. heaven forbid you're going to be documented for the next 100 years and not have your hair correct, right? and the idea is that once you've passed away, anyone with access can ask you anything and you'll answer them. tell me about your eyebrows. chuckles. these eyebrows are quite extraordinary. the concept has attracted someone with more than their fair share of stories. an absolute pleasure and privilege to meet you, sir. how are you doing? hi, nick. how are you? you know this place quite well. you've been here before, right? every nook and cranny, every crease and crack i know. just think of what the possibilities are of what you and i are doing right now. why did you record yourself? i ask myself that question day in and day out. i mean, artificial intelligence is fascinating for everybody.

the discourse now is is it coming alive? will it be the equivalent of our human creativity and devilishness? or is it stilljust mechanical, so 0k, why don't we just pull the plug? that's why i'm here. do you think that other people using storyfile�*s technology even come close to, like, what you can do in the way that you can tell stories? like, who cares about people that are not william shatner? everybody�*s got a story. i mean, if you and i were to talk — if i were to interview you, i would discover your story. you know what i would do with you? put the camera on him. no, don't put it on me! is the cameraman gonna listen...? you're listening to him? i'm going to stop talking. laughs. nick. yeah. when did you start combing your hair that way? this is actually a really good question. well, of course! no, stop — come back on me. ok, so that's what i would ask you, that sort of thing.

everybody has a story. were there any questions you were asked where you thought, i'm not going to answer that, i don't want to go there. i don't recall ever saying "i'm not going to answer that", because... although this is for publication, it's i'm dead, so... laughs would you reveal secrets? what's a secret? give me an idea of what is a secret. say when you were alive, say you had a dark secret... what's a dark secret? i've got loads of dark... like what? i can't tell you! give me one dark secret. make up a dark secret. i don't know, i could have stolen something. 0k, i've got a dark secret, i stole something, i've never talked about it, but i did, as a kid. i stole candy from a drug...grocery store. and as i am leaving the grocery

store, i am like... ten, and i go, i hear, and a hand is clapping. "0h, gee, what is that!" "what have you got in your bag?" "i got nothing! got nothing!" "let me see what you got under your jacket". a bag of candy. why wouldn't you want that dark secret? because that dark secret is going to die with you. it's gone forever. as well as playing back answers straight, for some clients storyfile is putting artificial words into virtual mouths. we don't call them deepfakes because they are not a hack of somebody�*s identity, they are done in an authorised way often with that person's estate, where we will recreate the character using their archives, their videos, their voice and create an absolutely lifelike version of that individual. say for a museum or a family trust. is there a danger there that you might misrepresent them or perhaps convey a different side of their personality

they never actually had ? are we capable of being able to misrepresent somebody? yes — in the same way that any, you know, film—maker could do that when making a movie or whatever. we created an a ai ethics policy and an ai ethics committee and advisers, external advisers. it doesn't always get it right. sometimes it struggles to understand what question you are asking. but on the flipside, the ai often groups recorded answers together to form fuller responses, revealing surprising details. i've got too many horses. i love horses. some people will be watching this thinking, oh, i'm not sure about communicating with a loved one after they have moved on — and is that a healthy thing to do? we as a technology company can't determine how people are going to live their lives when their loved ones have gone, any more than we can with a book or an album or anything else. that's not to say we are not responsible, what we're saying is that each of us has

different ways of thinking about our loved ones when we are gone, and dealing with grief in different ways. whilst the notion of chatting with the dead is certainly bewitching, arguably as ai advances, an ethical tightrope lies ahead. but for bill, this technology could enable him to boldly go where no—one has gone before. time for a look at this week's tech news. the white house has backed a bill which would give them the power to ban foreign technologies like tiktok if they pose a national security threat. the bill has been introduced by a group of bipartisan senators, and marks an escalation in us efforts to restrict tiktok over fears it could be used by the chinese government to access users' data. that is something tiktok denies would happen. alphabet�*s owned drone delivery company wing is scaling up its operations with an autonomous network of drones. participating retailers will also be able to use wing's new autoloaders to preload

packages for automatic pickup. during this, we break that time link between the package readiness and the aircraft readiness, and this provides a lot more flexibility in their operations. a bbc investigation has found hundreds of accounts recently allowed back on twitter have been spreading abuse or misinformation. the bbc analysed over 1,000 previously banned twitter accounts reinstated under new owner elon musk and found evidence of problematic content posted on twitter in over a third of them. and finally, tesla has cut prices for its electric cars again as it tries to boost sales and compete with rivals. the latest round of reductions, which vary across locations and models, are the fifth change tesla has made to prices since the start of the year. let's talk about shoes — all shoes, and the challenge

of them being comfortable. i love a pair of heels. they make me feel kind of more powerful, ready to perform. why are you so much shorter all of a sudden? and almost the same height as spencer. but they are not without issue. if you are put in a position on high heels, you are pushed into a forward position, you have to extend your back. if you look, all the nerves and all the joints are put under stress when you extend the back to compensate. 0uch, not good. aside from the potential back or hip pain, they can really hurt your feet. but maybe there is a solution. foot scanning for custom—made insoles is nothing new, but these alia carbon—fibre titanium and nano—material ones go in at the point of manufacture

as a base to the shoe. and they aim to make even the glitziest of heels feel as comfortable to wear as the comfiest trainers. in a normal high heel, only about 20% of your foot is in contact with your shoe, because all of the pressure is built in and focused on the metatarsal heads, which is the ball of the foot. so, with our technology, by re—engineering the structure where you get less pressure on the balls of your feet, and by loading more on your heels, we are able to decrease the lower back pain that people feel, as well as the knee stress because they are not trying to overcompensate and regain their centre of balance. whilst taryn brings her orthopaedic surgery skills to the mix, her co—founder enrico knows a thing or two about shoes fit for the red carpet. brilliant. well, designer enrico already has 2a different fits per size available, but he tells me that is not enough.

no, you're perfectly right. size really doesn't exist because ourfeet speak a language that is unique. 0k, well, last week i sent you some photos of my feet next to a tape measure, so you have got an idea of my size, and you have picked out of the ones that are already made, which ones are likely to fit the best. but you don't think they are quite right yet. what is wrong with this fit? it's not enough tight because you have a 35.5, 36 in this area of the foot. so different parts of our tootsies are different sizes. but as most people don't have enrico and his tape measure at theirfeet, the idea here is that a 3d scanning machine will be available in shops to do the analysis. initially, this will be for enrico's designs, but it's something that other shoe companies could embrace. the device's detailed scans will be used to make custom—made shoes that should fit perfectly all over, including the insoles, to balance out the pressure. i think it's very important

that shoe manufacturers are looking at this, for a start. i think if you talk about reducing pressure on the foot, that will definitely improve some of the biomechanics in the foot, so will definitely improve foot pain. other companies are coming up with their solutions to the problem too. these look like a regular pair of heels, right? gait:tech also combines biomaterials and orthopaedic knowledge to develop insoles that can be put in at the point of manufacture. although they are not personalised, they too aim to redistribute pressure and better biomechanics. so the test is, how do they feel? the real benefits should be felt when you are wearing them for several hours, but i am going to give them a try now to see how they are when you first put them on. ok, the first thing that i'm very conscious of is there is a little bit more support at the back of my toes than i would normally feel.

i thought they were going to support the arches more. that still feels normal. i still think that the comfort of shoes is largely dependent on how soft the leather is around them. but perhaps what i have noticed now as that i am only walking up and down in this small space. i'd need to do this for a couple of hours to really get a proper idea. i'm still not sure that i am convinced that even though they feel better, heels will ever be as comfortable as flats. but i haven't put the custom—made ones to the test yet, so let's see. and now, we have the grand unveiling of the shoes, because they've arrived and they're going on right now. yeah, the most noticeable thing is that they feel quite tight to get on, but that is i guess that's how you find a shoe actually fitting once you're wearing it maybe. they do fit well and they feel like they have got gel underneath them. the only issue is that at the moment they are available in just this brand of shoes, so they start at $795 — not exactly a solution for everyone. yeah. i tell you who could

afford them, though, is the stars of our next story, because it is the oscars this weekend, and 13 years after the original avatar movie cleaned up at the awards, the sequel is finally here. avatar: the way of water is up for four 0scars, including best visual effects. so it is time for us to meet the team behind the scenes. to me, the film was all about the characters. i hear her heartbeat. we are able to bring the performance of these great actors onto cg characters and have audiences still react — that's the amazing part for me. what does her - heartbeat sound like? and so for that, we wrote a whole new neural network— based facial system to understand a little better what the actors are doing and to give the animators a finer level of control

over the faces. a lot of times you think effects and you think big scale, and that is all part of it as well, but we also like to make sure that the small, intimate moments work, because those are really where the audience gets to understand and know the character. you are very hard on them. i'm theirfather, it's myjob. we like to do a film like this that has a wide range, like, where you are exploring the world in new ways. every day is a school day, studying what water looks like at different depths, you know, if you are one metre under or if you are 50 metres under, what happens to the light depending on how clear the water is, we looked at water from all around the world to see which types would

play best for the film. obviously we knew we were going to go with something tropical, but you still study everything anyway just so you kind of know where you are. of real whales, of dolphins, of otters, of different types of animals under the water, how they swim, how they interact, the way bubbles work around them. the sea is your home. you have that expansive canvas to work with. but then you also have the big dramatic things that happen, the hunt. strong heart. the battle scenes. you have all of that on one side and then you have families understanding how to live together, and sometimes working and sometimes not. like, it's all very familiar. i see you. i think the great thing about science fiction is it lets you see what is kind of normal to us

but in a new light. so maybe you think about it a little bit more than you would otherwise. this family...is our fortress. i remember the thing about the first avatar was it was all about the 3d, which in the end, didn't seem to catch on like it was supposed to. but the thing i love aboutjames cameron as a director is he is really hands—on and always willing to push the boundaries. yes, and good luck to all of this weekend's 0scar nominees. that's all we have got time for. yeah, thanks for watching. we'll see you soon. bye— bye.

hello there. let's take a look at the weather for the week ahead. we're into some much milderfeeling air now. so thursday's temperatures a lot higher than they were on wednesday. some rain around at times, particularly for western parts of the uk. this is lancashire, some rather soggy footpaths here. no big changes as we head through the rest of the week. so it stays mild — temperatures above the seasonal average and it will be really rather unsettled. so more wet and windy weather to come particularly out towards western spots. low pressure remains a dominant. it's just sending these atlantic fronts our way, so wet and windy and also really very mild. that mild airfeeding through on the brisk south—westerly winds. you can see that marked in yellow. the cold air hangs on in blue towards the far north of mainland scotland and across the northern isles and that's true for the rest of the week. now, on friday morning, a cold frontjust reinvigorates across the channel islands, the far south east of england, east anglia. so some heavy downpours here potentially through the morning, but it will clears off into the afternoon. elsewhere for the rest

of the uk, there will be more sunshine than on thursday. the winds are a little lighter, but the daytime heating could help to spark off a few heavy, even thundery downpours, but they will be fairly localised temperatures again on a par with thursday, so 13 to 15 degrees celsius. a local 16 always possible in all of that mild air. and of course, the air stays mild on friday night into saturday. another weather front approaches western scotland here. but elsewhere, a lot of dry weather, a few clearer spells, but temperatures frost—free between six and nine degrees celsius, maybe just a touch of frost where we see prolonged clear spells in sheltered glens of scotland. now a weather front approach is scotland, west of scotland as we head through saturday morning, some showers, some longer spells of rain here or so moving through northern ireland and approaching north—west england by the end of the day. elsewhere for much of england and wales, a lot of dry weather, but some more showers popping up as we head through the afternoon. it's certainly more showery than on friday. temperatures between 11 and 1a degrees celsius for most of us. the south—westerly wind becomes a bit more north—westerly, though, as we head into the second half

of the weekend, as our area of low pressure just continues to push its way eastwards. and that, of course, is going to bring us some slightly cooler feeling air by the time we get to sunday with that north—westerly wind. the temperatures are still a little above the average for this time of year, but the air will feel cooler than on saturday in that north—westerly. it's quite a cloudy start to the day, a cooler start as well. there will be some brighter skies developing, i think, as the day wears on. another weather front approaching from the west as we head into sunday evening, but it should stay dry for most of the daylight hours. temperatures a little lower, peaking between nine and 13 degrees celsius for most with a little bit of added wind chill towards exposed coastal areas, of course. now into the start of next week, we're back to the south—westerly winds, we're back to that very mild air. again, it's going to be unsettled for the start of the week. wet and windy again at times, possibly turning a little colder by the weekend. but it's still quite a long way, meteorologically speaking. so the south—westerly wind returns — you can see that in yellow here.

we've still got the easterly across the northern rsa, still staying very cold here. and as you can see, it's very mobile. all of these atlantic fronts just working their way in from the south—west. it will be wet, it will be windy, particularly towards western facing coast. low pressure is dominant. and here is the outlook for some of our towns across the uk as we head through the rest of the week. so on tuesday, temperatures already lower than they are at the moment. those temperatures will dip as the week wears on, but it does stay unsettled. so more wet and windy weather to come in the forecast.

i'm david willis in washington and this is bbc world news america. a debate over the retirement age, rages in france. police clash with protesters after the french president emmanuel macron pushes through controversial pension reforms, without a vote in parliament. coming to the financial rescue — a number of big us banks team up to provde billions in funding to troubled lender first national. the us military releases footage that it says shows the moment a russian jet took down an american drone. and, authentically african. senegal celebrates the rich

traditions of the continent's fabrics and textiles — with some of africa's leading