I am attending a still life course next week and we are encouraged to bring our cameras, and as it happens I have access to a new one. The office has just bought a Canon EOS 5D MKIV – someone passing through Dubai – which is a bit of an upgrade from our 350D ‘Rebel’ that was getting a bit tired. While I am loving using my 35mm primes again – and full frame – they are not the fanciest: Canon EF 28mm f2.8 Canon EF 50mm f1.8 (two of these, one of which comes apart on occasions) Canon EF 85mm f/1.8 USM Canon EF 135mm f/2.8 And that’s it. But … I have loads of Pentax lenses and Canon adapters and could take along a manual Pentax SMS 50mm f1.4. I need to do a bit of cruel surgery to it, to stop the Pentax protrusions blocking the 5D’s mirror. I am not sure I mind doing this, as I never had a real liking for the lens (I much preferred the cheaper SMC 50mm 1.7). It was always too heavy and bulky on lovely old MXs (which – temporarily – now don’t work as the mirrors are gummed up). I think the 1.4 would be fine on the Canon, which is big enough for it, and it could have many uses if adapted. Which lens should I take for this evening? (I think 2 is enough). Is it blasphemous to chop up a blameless `Pentax SMC 1.4 lens to adapt to Canon?