We all have favourites that may change over time, but what is the lens that will have to be 'prised from your cold dead hands'?
Doesn't have to be the most exotic or expensive lens, but one that you can't bear to part with.
My own choice defo would have been the Loxia 21 a number of years ago, but have been shooting with wide angle zooms for the flexibility in framing.
For me it's a difficult choice, my most exotic is probably the 135GM, but I'm going to have to say the Sigma 40 Art and be dammed with the weight, it's just too good. Great for landscape, people, car shows, not done astro with it yet but it's on the to do list.
Without a doubt my number one keeper is the Noct-Nikkor 58/1.2 AiS. After that my two Voigtländer APO-Lanthars: 125/2.5 & 180/4. All of these are irreplaceably useful and now priced beyond my pain-threshold.
The 50GM 1.2 but I really like the Loxia 25 and 85 and would be unhappy without the 35GM. Those 4 can make a nice outing. The Batis 135 and 18 are things I would miss too. Sigma 45 and 24 3.5. There I pretty much named 8 out of my 10 lenses.
Currently the 135GM, been barely off the camera body unless I have the 16mm Viltrox on, which I also like. Weird, long or wide, I haven't really liked 'in between' since I was on Canon - then it would have been the Sigma 85 Art.
CV15, 28-60. Odd choices to some, but I use them for travel often. The CV15 was one of the "choppy" lenses tested by Guy and centered, and the 28-60 was Fred's that tested & performed really well. Wouldn't want to take a chance of different copies, and both are responsible for wall hangers.
These 2 are due to constant usage.
70-200 2.8II- does sports and all the other things 70-200's can do.
50 1.2- portraits, group shots, low light. Results I've gotten, even at 1.2, make it a must-keep for me.