The correct dome positioning for ESB Vader is one that I have followed for a looong time now.
Although some members here have the TM dome the display still needs attention. The main thing I was trying to find out a while ago was why did the dome look wonky etc.. and why couldn't I get my SPFX etc..to look right after modification? Well although I improved the look of the fanmade I relised it was just indifferent anyway and after receiving the TM dome all became clear. The dome is very different to the other offering from fanmade ESB domes. Although the TM dome is the same as the screen ESB it needs to be sat on the fixing mech so these things below line up.
This brief guide may help reduce time and effort for those who seek that accuracy that has made me gain a few extra grey hairs and a whole lot of stress. This research is being documented as breif but the in-depth version has taken many many months and hours. I hope this is beneficial to some?
As you can see, the TM dome is correctly sat on the faceplate (give or take a fraction) from this picture from Tom a while back, however..the dome always looks different on the ground, a true test is on a mannequin where the dome should lift.
All explained breif
As you look at the picture the left and right are obviously reversed regarding Vader. Not to confuse I will go with Vader, for example. When I say left dome, that's VADER's left, our right as we look at it.
*Although the dome position and angles do change throughout the movie according to how they put the dome on and Vader's (Prowse's) movement this guide is consistant and features the same exact set up in the majority of TESB. The pics I have posted do vary very slightly but are more or less the same. Keep in mind Vader is looking up in one pic and more central in the other*
1) Vader's bottom right of the dome is angled so it appears longer than the other side.
2) The dome is not symmetrical at all. Vader's right hand side is positioned to give far less flare when compared to the otherside. Notice the angles are straighter in appearance than the other.
3) Above Vader's right eye the dome arch is slightly different to the other side. The arch and positioning that meet above the right eye shows a definate smaller gap between that and the other side. This is consitant throughout the movie.
4) The beginning of the peak or strip for a better word is mainly consistant with the first 1/4 of Vader's eye arch if you line this up width ways. The gap between the last nose slot and the beginning of the centre strip is under 1/2 inch apart.
5) See bigger ref pic. The centre strip is not dead central. I know this should be in the mould of the helmet etc.. but the right of the beginning of the strip is not in line with the faceplate frown lines nor should it be. It should be fractionally off centre. This is what helps to create the difference in brow and arch size.
6) Throughout Vader's right eye brow and arch combo is considerably bigger.
7) A bigger gap all around the arch is obvious throughout, If you do not catch the angle dead central this will be more pronounced anyway. The bit highlighted is actually showing the same arch section on this side looks like it is marginally positioned higher. It is quite noticeable.
Again as the dome flares to Vader's left more this creates a bigger gap.
9) Once more the dome flares far more to Vader's left. A bigger gap is not only visually noticable on measurements taken there is a difference naturally.
10) Beginning of bottom edge of dome is higher than the other side.
11) Very noticeable difference on how the dome sits and the position it meets when compared to the other side.
12) Th greatest indifference IMO comes from the gap beginning with where the arch meets Vader's right eye brow etc..
I can go on and on but this is a quick summary
Very Brief summary on ESB dome irregularity's
*As before, when I mention left, that is Vader's left, right as we see it*
The helmet always looks different off than on. The dome pulls into the faceplate and gives an inaccurate representation
1) Vader's right hand side brow arch is lower.
2) Again the arch nearer the centre srip where the eye nearly meets is closer than the other side.
3) The left front of the centre strip peak beginning is angled/trimmed fractionally upwards.
4) The centre strip is not central. It angles more to Vader's right fractionally.
*Note* This picture contains a strip that looks thinner than the actual screen used prop. I believe this may be lighting. If you compare the thickness to the ANH strip from a screen cap etc, ESB is fractionally wider. Same strip as ANH but they tried to straighten out the curve and made it wider in the process.
5) Vader's left arch brow is higher.
6) Again the arch is not symmetrical or in line to the other side.