I just bought the ZOMEI 0.45x Wide Angle Adapter to put on my Tamron 17-50mm/2.8 VC when on 17mm to try to have more angle of view on my pictures.
I noticed something strange but positive enough to mention : The photos are far sharper with the adapter then without, at least in 17mm !!! The quality is fantastic.
My question for you all, is how to evaluate at what angle am I now by using this adapter on 17mm ? It's said 0.45x but I noticed that I gained only few more in my pictures but not sure it's 0.45x17=8mm (rounded), how much should I have now with this adapter depending on your experiences? 10mm ? 12mm? 15mm?