17/08/2017 4:57 AM AEST

Don't Worry, No One Got Seriously Hurt Filming That Fiery 'Game Of Thrones' Battle

The stakes have never been higher on “Game of Thrones” ― for the characters on screen, but perhaps even for the real people behind the scenes, too.

Season 7 gave us the most violent battle since the bastards’ brawl with its fourth episode, “The Spoils of War,” bringing Daenerys’ (Emilia Clarke) dragons and Dothraki screamers to face off against the Lannisters’ traditional Westerosi army. With fire and blood, she terrorized her opposition (and gave her councilors more to worry about). Impressively, the loot train attack was shot with real horses and flames in a timespan of more than two weeks. Crew set a record 73 stuntmen on fire ― 20 at the same time ― to capture the proper scale of the battle.

But as a testament to the professionalism of everyone involved with “Game of Thrones,” no one got seriously hurt, the episode’s director of photography, Robert McLachlan, told HuffPost.

“I think one stuntman took an unexpected tumble off a horse, but he handled it really well and got right back on. But apart from that, no, as far as I know,” he said, adding, “even though it was a potentially really dangerous scene to film.”

McLachlan has filmed eight episodes of the hit series to date, including “Spoils of War” and Sunday’s “Eastwatch” in Season 7. We spoke to him this week about the challenges of shooting the series now that it’s moving along faster than ever ― and just how closely fans should look for hidden Easter eggs:

"Game of Thrones" director of photography Robert McLachlan.

In Season 7, as so many storylines are converging and we’re finally getting to the endgame, it seems the mood of the show has become darker and more urgent. How do you try to reflect that?

A good cinematographer, I think, will let a location speak to them first and foremost, because if we try to fight the natural light [...] usually you lose. So you try to embrace those things. But also, if you have to, if the story really demands it ― like the loot train attack ― obviously we wouldn’t want it to be too pretty or backlit the whole time. Luckily, I had the advantage of, and the excuse to, add a lot of smoke and flames into those frames. What the smoke really did, and I was counting on it from the time I read the script, was to help hide the fact that the weather was continually changing in September when we filmed that scene in Spain. A lot of it really helped me get over some technical things. In a scene that’s shot over, I think in this case it was 18 days, and [the finished product] takes just a few minutes, you don’t want a shot that’s dark and overcast bumping up against a beautifully sunlit shot. So, I knew going in that the smoke was really going to be my friend in a lot of ways. In one sense, it would help hide the fact that it was cloudy as opposed to sunny, like it was at the beginning of the battle. But more importantly, it would filter it and create a haze and literally a “fog of war,” where a lot of the background could be suggested as opposed to stated, and make it that much more textural. And really, I wanted to make it look not like any of the other battles that have been done on “Game of Thrones.”

Yeah, “Spoils of War” definitely felt different. What were some of the other difficulties there, aside from making sure nobody got hurt?

If there’s one thing the producers put first and foremost on that show, it’s everybody’s safety. A good example of that was: I really wanted as much nasty black smoke billowing through that scene as I could. The special effects smoke that we usually use is white, and it’s very innocuous and it’s safe to breathe, [but] in order to get nasty black smoke, you have to burn diesel oil. The crew could wear masks and goggles, but the cast could not, and after two days we were all coughing and wheezing and the HBO safety officer said, “OK, that’s enough. No more black smoke.” So I had to sort of roll with it, and then light it in such a way that it looked like it was through smoke, and then have our friends in the visual effects department help us out.

Season 7 is moving so much more quickly than the series has in the past, and “Eastwatch” particularly so. Does that make your job more challenging?

That is a big challenge, because it means you’re in a lot of different locations. In this case, we were in several parts of Spain and all over Northern Ireland as well as at our stages in Belfast, where we have our big sets. And you never really settle into one place, because a lot of those dialogues scenes ― you only have a short day to film them, and that meant a lot of bouncing around and really having limited time. But luckily, on that show, we have enough preparatory time where we can plan very, very meticulously so we know what we’re going to do when we get there. I would say of the eight episodes that I’ve photographed, both these ones were by far the most challenging. 

When everything needs to be so planned out on “Game of Thrones,” because you’ve got so many moving parts, how do you still allow yourself to be creative?

The creativity comes in in different ways. The nice thing is, when you’re sitting in front of a dark stage, that’s like an artist sitting in front of a blank canvas. You can start painting with light, if you will, and using your camera as another part of your palette. In that sense, there’s a lot more on-the-spot creativity, for me. In other cases, the creativity really has to come in far in advance, because it has to be planned so specifically when you know you only have so many days when you have several hundred extras, and a week later you’re only going to have a couple of hundred extras, but you always want it to look like you’ve got thousands. You’re planning almost to the minute what time you’re going to do each of the many shots you need to do for a sequence like that. 

That level of planning is amazing. But you mentioned painting with light, and one thing we know about the show’s composer is that he’s tried to use music to describe each character individually. Do you ever try to use light in the same way, differently for different characters?

For me, the light really has to be determined by the location that you’re in and where it would feel the most natural coming from. And how contrasty you make it or what have you, how moody and stuff, that’ll be determined by the script itself much more than the characters themselves ― other than when we’re filming Cersei or Daenerys. In which case, you always want them to look terrific.

Were there any subtle moments in Episodes 4 and 5 you hoped viewers would notice that maybe we missed?

Just from what reviews I saw, I think people were pretty astute. They picked up on some of the more subtle things, like Gilly practicing her reading to Sam, and him not noticing what she’s saying ― which would have been a major “a-ha” moment. But no, apart from what people have noticed, there’s not really any major Easter eggs in there, I would say.

Good to know what you see is what you get sometimes.

I’ll be honest, when I watch other people’s episodes, I’ll catch stuff I didn’t see in the script, or in their dailies. And sometimes I’ll catch something in a performance that really meant something that I missed on the day because I was so busy trying to deal with galloping horses or lighting problems or what have you. A lot of that stuff comes out in the editing.

“Game of Thrones” airs Sundays at 9 p.m. ET on HBO. This interview has been edited and condensed.