From day one of owning my e-m1 I have been adapting my Canon FD lenses to it. I hadn't shot with my A-1 for almost 2 years and I was excited to retry my vintage glass on the MFT format. I have a 24mm, 35mm, 50mm 1.8, 50mm 1.4 and. 100mm. Most are the S.S.C versions so they really make some fabulous renderings. The 100mm is mind boggling sharp IMHO. But then the problem. The 50 1.4 was showing some serious CA and blooming wide open. I didn't notice it until post and was disappointed at first that my lens may have a problem I never noticed before. I shot only b&w film with it so it could have gone unnoticed. Here is a shot with the Canon 50mm 1.4 FD wide open. I processed it in b&w because the CA was too distracting. You can see the 'blooming' as a glow around the highlights of my daughter. I searched around online (not extensively) and saw lots of adapted 50mm lens shots that looked sharp and wonderful so I was almost sure it was my lens. Last week there was a camera show in my area. Basically a swap meet for old film camera gear and I went hunting. I found a sweet deal on a minolta rokkor-pg 50mm 1.4 for $50 and snatched it up. Grabbed an adaptor and went to work again. Low and behold. Deep CA and blooming again. Here is a test shot in the worst conditions. Hot light on a reflective soda can. Panic set in. I thought maybe my sensor was shot. I thought to myself "did I point the camera directly at the sun the other day in a zealous effort for a sunset shot?!!" So after some more digging I found that apparently blooming and CA can be a problem with fast vintage lenses. I never had the issue, as far as I can recall, when I adapted the lenses to my 7D but the experience was so poor with that camera I only did it once or twice. The blooming happens in high contrast areas and has to do with how the light is being interpreted by the sensor. The intense light at f 1.2 or 1.4 from a un-categorized lens can cause the contrast area to bleed over into other pixels on the sensor. I wonder if this is only a problem for high Megapixel MFT cameras because of the size of the sensor and tightly packed diodes? So the way to fix it? Stop down. After some more photos I found f2 to be sufficient to clean up the rendering and limit any CA and blooming. Here is a fav stopped down to f2.8 The funny thing is now that I know when it happens I plan on using the bloom in situations where it might make for a beautiful effect. For instance this shot is pretty neat with the glow around the face. Forgive all the kid photos. I haven't had the camera long enough to take out the vintage glass somewhere other than home. They also happen to be my favorite subjects So if anyone has anything to share and discuss please do. I love 'slowing down' again with the old lenses and didn't realize how much I missed shooting 35 film until now. I plan on picking up more as I feel that these old lenses have characteristics you don't get in modern lenses. I happen to like flaws as long as I understand why they are happening (to some degree). What's been your experience?