Hi,

If one reads some of the specifications for Horseman cameras
listed in the following link:

http://www.kenko-pi.co.jp/horseman/e/faq_tc.html

one will find that some lenses longer than 210mm. may not
be used with the regular lens boards because 'flange focal distance
is too long', or 'length of monorail is short', or some other
reasons.

http://www.kenko-pi.co.jp/horseman/e/lens_list.html

Are extended boards, like this one, an accesory that may help
use lenses longer than 210mm.?

https://www.ebay.com/itm/Horseman-Ex...a/273441254590

Thank you in advance, kind regards!