Piero del Pollaillo's lancers and horses

Salve,
a short trip to the XV century world of chivalry and religious art of the Italian Peninsula, where in the north, in Lombardy, Tuscany and Veneto many talented and prolific artists flourished working for the Catholic Church and various wealthy patrons. 
ad rem,  a lesser known Florentine artist Piero del Pollaillo painted a huge canvass showing the martyrdom of Saint Sebastian, a fairly common religious theme among the period (XV-XVI century) painters.
This painting contains some interesting information about the period in the background, namely, apart form the foreground scene of rather gruesome martyrdom, the very background of this masterpiece shows horsemen - lancers or knight and men-at arms - in various posses and angles.
They appear to be wearing a Milanese type of armor, popular in the XV century throughout the Christian world of Europe, along with the Gothic one.
Horses are not too tall, but powerful and stallions, bay, black, and various gray.
These are members of the chivalry and military, these armor being awfully expensive while their war mounts were almost equally costly, and more prone to injury and loss.

 the above lancer holds a very long lance, I played around with the proportions and it seems to me that it might be a weapon over 4-4,5 meters long (the horse is a warhorse or dextrarius opertus, about 1,5m tall at the withers, the man is rather tall so perhaps 1,7-1,8m, together they stood about 2,2-2,4m tall, and the lance is more than twice as long as the height of the mounted knight). Perhaps it is a fluted lance, or a hollowed one like the winged hussars, for the grip on this lance is rather close to its butt?

 this figure on a black horse (a raven one - :) ) and his companion appear to be some sort of commanders, with their fine armor, and the maces they wield around. Their horses have particularly fine saddles, perhaps painted or covered in red leather as well as the tack is red leather, with tassels. Serious long shanked curb-bits are used and only a single set of reins. There is no crouper, but the tail is tied, German fashion? Perhaps these are Hungarian knights, as the long haired figure bears some resemblance to Mathias Corvinus, who knows?

very little here is seen, but the partial view of a dextrarius, bay with fine but not flashy breastplate, curb-bitted and collected.

more fine powerful warhorses and riders, at least two riders are with lances, one appears to be wearing an arming doublet.
enjoy