What is John Wall (inventor)?
{{Infobox engineer |image = JohnWall.jpg |image_size = <!-- if image is smaller than 250px. Use bare number; do not add a px afterward --> |alt = |caption = John Wall |name = |birth_date = {{birth date|1932|06|26|df=y}} |birth_place = [[Crayford]], [[Kent]]<!-- Do not change to London, Crayford was in Kent in 1932 -->, [[England]] |death_date = {{death date and age|2018|01|27|1932|06|26|df=y}} |death_place = [[Coventry]], [[Warwickshire]], England |education = |spouse = |parents = |children = |discipline = |institutions = |practice_name = |employer = |significant_projects = |significant_design = [[Crayford focuser]] |significant_advance = [[Dialyte lens#Dialyte telescopes|dialyte]] based [[refracting telescope]]s |significant_awards = |signature = }} '''John Wall''' (26 June 1932 – 27 January 2018)<ref>{{cite web|url=http://crayfordjohn.webs.com/index.htm|title=John Wall|date=6 March 2012|website=web.archive.org|access-date=30 January 2018|archive-date=6 March 2012|archive-url=https://web.archive.org/web/20120306233913/http://crayfordjohn.webs.com/index.htm|url-status=bot: unknown}}</ref><ref>{{cite web|url=https://cmhas.wikispaces.com/|title=Wikispaces|website=cmhas.wikispaces.com|access-date=2019-02-15|archive-date=2018-09-20|archive-url=https://web.archive.org/web/20180920054645/http://cmhas.wikispaces.com/|url-status=dead}}</ref> was an [[English people|English]] design engineer, [[amateur astronomer]], and [[amateur telescope making|amateur telescope maker]]. He was a member of the [[British Astronomical Association]] until his death in 2018. He was known for designing [[Dialyte lens#Dialyte telescopes|dialyte]] based [[refracting telescope]]s, coming up with the ''Zerochromat''.<ref>{{cite web|url=http://www.hanwellobservatory.org.uk/telescopes/john-wall|title=John Wall refractor - Hanwe