Not only the photography process was more complex; add that for episodes 5 & 6 it was already costly in comparison to the previous ones due to using 35mm, and episode 6 of
Aim for the Top! Gunbuster in particular was shot on a non-anamorphic widescreen 16:9 ratio which is an inefficient use of that film format, plus other one of the reasons was the little planning behind
Hideaki Anno's decision (that stubbornly didn't want to decolourise it during post-production). As
type-r (
@hitasuraeiga) fact-checked, for the colour coordination on the project it was deemed necessary to reformulate the colour sample for the painters
due to the insufficient "10-tone grey charts" used for the previous episodes. No planners were experts on designing monochrome charts that took advantage of the innate contrast accentuation,
simplicity and novelty Mr. Anno wanted from this, which made it the most difficult, time-consuming and subsequently expensive part of the production.
Also, the main photography was shot on colour film because the B&W film would have been even more of a money-sink, due to the (already at the time) unusual of the process and because of it the scarcity on specific film developer chemicals used.