Minolta SLR MD Macro-Rokkor 50/3.5 on Canon EOS

Though my Canon 7D DSLR camera has not been used so much for 10 years, it works whimsically sometimes, under exposure value result with too high shutter speed, today 2 ill-shots per 12. I think it is not used so often, something must be wrong internally, ROM bag or something? But, I don't mind at all, the result is up to Heaven entirely.
This Blue Lily Africanus was recorded utilizing Minolta SLR MD Macro 50/3.5 with fully opened iris.
As we know, Minolta SLR standard flange back is 43.5 mm, on the other hand, Canon EF mount has that of 44.0 mm, resulting infinity focusing is undesirable, 0.5 mm discrepancy causes critical problem if Minolta SLR lens is put on the Canon EOS body if the flange surfaces might be met together precisely.
I have succeeded in utilizing it without any optical additive converter.
If expose I a spacial way to do that here, all the Minolta SLR lens lover must regret to have thrown away it.
The scheme is like that, all the lens have the infinity helicoid position adjusting mechanism and the lack of flange back value could be compensated by adjusting the construction, the lens unit is moved 0.5    mm back word relatively easily, this principle is applied even on zoom lenses, so over 10 Minolta lenses were modified like that with very low price. 43.5 mm flange back value meant no way to modify to adapt on another DSLR bodies at all. This is why old Minolta SLR lenses were prevailing in the market at the lowest prices, but the price has been up recently because of smaller flange back mirror-less DSL body is thrown in to the market.