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Inspired by the latest video by @EckhartsLadder, here is my thread about the size of the Arquitens. Is Gideon's Arquitens the same size as the previous Arquitens? Well... yes and no. (Dedicated to @ScoutTheTrooper and @maredfield who have also done measurements)
The Arquitens Light Cruiser first appeared in The Clone Wars episode "Grievous Intrigue", it appeared a few more times during the show and (while it was never official) if you calculate its size, the ship should be about 200m long.
A slight different version of this ship, the Arquitens Command Cruiser appeared in Rebels, while there are some changes the ship appears to be the same size, about 200m long.
The bridge of the ship, in both Clone Wars and Rebels, by measuring the size of a human and the exterior, you can tell that it fits the 200m long size.
(Just to note that not every ship in The Clone Wars has been cosistent about its size, but in this case, everything seems to indicate 200m long).
Now, here is where it gets messy.
Between 2014 and 2016 there was a magazine by De Agostini called "Build your Millennium Falcon", this magazine featured instruction to build a Millennium Falcon model and a mini-article.
Which, by the way, if you get your hands on those magazines, those little articles are very neat, they have some images I haven't seen in other informational books.
I don't know if this was born here, but in the issue 60 it was officially stated that the Arquitens was 325m long. Which seems to contradict what we had seen up to this point, but now it was official. Every Arquitens we had ever seen was now 325m long.
Later, when the ship appeared in Battlefront II the model was 325m long. The ship was slightly more detailed, but it was, in essence, an upscale version of the ship we had seen at this point, with no big changes.
So, when the ship appeared in the Mandalorian, they used the official size of 325m, but this time they made the ship fit that size. Now it can hold a TIE (and a hangar) between it's prongs, the bridge is bigger... They added more engines and more detail everywhere.
If you scale the ship using the TIE hangar and the bridge, it fits with the 325m size, even if the bridge and prongs are larger than the one seen in Rebels and Clone Wars, but that's because it was smaller back then.
So canonically, they ARE the same size. They are supposedly 325m long all of them. At least on paper. Visually they are different.
But. This is not over yet. There are in the Mandalorian. The shot of the Dark Troopers launching from the Arquitens hints at a larger ship. This was probably done because it looked better in the shot.
The second and bigger inconsistency is the Lambda Shuttle. In a span of 1 minute you see a Lambda Shuttle going through a hangar where a TIE Fighter could barely fit. You can see it clearly in this animation by @sethlunchquest : https://twitter.com/SethLunchquest/status/1340532708494123008
This inconsistency is obviously there for plot reasons, you can even see the shots of the hangar where the size of the cockpit doesn't fit with the rest of the body, and the wings are so bent inwards that they would cross each other.
So this is it. There are other inconsistencies around Gideon's Arquitens but they are not size related. For example, the "bridge" hangar that they pass through doesn't appear anywhere from the exterior.
But in any case, Gideon's Arquitens is 325m long, that seems to be pretty clear while at the same time it is larger than the Clone Wars/Rebels Version, even if officially they are the same size.
