Is there any footage of the Chernobyl explosion?

I heavily doubt it because all the footage of Chernobyl is aerial so for it to be a video if it there would have to have been a helicopter flying over it before, and if there were footage of it we would know and probably have seen it.

This is so unlikely, I think its fair to even discount the possibility unless you hear otherwise.

Even in the USA in 1986 consumer video recording devices were a new luxury, and recording media had little capacity and was relatively expensive. As a result, very few people even in the richest country on Earth would just walk around randomly recording things. In the USSR consumer luxuries like this were pretty much unheard of.

Also, the Soviets were paranoid about attacks from the outside. As a result, they were super fussy about allowing any kind of pictures or recording devices of any kind around likely infrastructure targets like power plants. These weren't people amenable to innocent explanations. All the incentives set up in their system were to lock people up now, and ask questions never. So no person with a Wisdom score over about 6 would ever think to even bring a video recording device to that city.

There's pretty much no way someone would have had a video camera pointed in the right direction and recording at the exact moment the explosion happened.

I'm also aware that back in 1986 not everyone was walking around with a camera in their pocket.

Are you really?

It goes a bit further than that, my friend. Of course lots of people did carry cameras but usually for a reason. One didn't walk around with a camera 'just in case' or 'for the fun of it'. You don't do that with 'wet' cameras. Almost nobody had a mobile phone back then, and the few mobiles that existed didn't have cameras. A mobile in those days was huge. You needed a backpack to carry one. Literally.

However, the above is about the Western world, where people had the money and the freedom to walk around with cameras. Do mind that walking around with a camera near a nuclear facility in the west was and still is severely restricted.

Now we have a look at the USSR. A lot less people carrying cameras there. For two good reasons: USSR citizens had much less spendable income and the state wasn't particularly keen on people taking photo's without a good reason.

Next, we're talking about a nuclear facility in the USSR. That's a strategic asset of national importance. Photography there was absolutely forbidden. Merely walking around with a camera would get you arrested on the spot. Immediately. Even if you worked there, you had to have a bloody good reason to bring a camera to work. "Igor has his birthday party" was not a good reason.

Technical video camera's did exist, but they were both large and very expensive compared with modern equipment. So it is extremely unlikely the actual event has been or could have been taped.

IIRC the station operators weren't sure what happened initially because they had no cameras looking at the reactor. The first sign of how bad the explosion had been, was someone opening a door and staring into a crater.

From this timeline:

01:21 – Caps to fuel channels on charge face seen jumping in their sockets.

Valeriy Ivanovich Perevozchenko, the reactor section foreman, was present on the open platform at Level +50 shortly before the explosion. He witnessed the 350 kg blocks atop the fuel channels of the Upper Biological Shield jumping up and down and felt the shock waves through the building structure; the rupture of the pressure channels was in progress. He started to run down the spiral staircase to Level +10, through the deaerator gallery and the corridor heading to the control room, to report his observations.

At 01:23, the reactor blew up.

at 01:26, it was unclear to the operators that the reactor had blown up:

Dyatlov ordered reactor cooling with emergency speed, assuming the reactor was intact and the explosion had been caused by hydrogen accumulating in the emergency tank of the safety control system. Other employees went to the control room, reporting damage. Dyatlov went to the backup control room, pressing the AZ-5 button there and disconnecting power to the control rod servo drives; despite seeing the graphite blocks scattered on the ground outside the plant, he still believed the reactor was intact.

...They went through a narrow corridor towards the central hall, entered the reactor hall, and found it blocked with rubble and fragments; dangling fire hoses were pouring water into the remains of the reactor core, the firemen not there anymore.

This timeline suggests the reactor crew relied on eyewitnesses in the reactor room, which means they had no camera view. That makes it unlikely the explosion itself was recorded.