The first optics I used to image deep sky astronomical targets were fast Nikon telephotos at 200mm (f/4 and f/2.8). To image the milky way I used and I am still using the excellent and fast Samyang wide lens at 14mm (f2/.8). I was shooting with a stock un-modified Nikon D750 and the tracker was a Star Adventurer with a Manfrotto/Gitzo tripod. My very first tripod, the one I used to shoot my very first milky way images in Kefalonia island was a small Gorrilapod!
What my Nikon DSLR recorded in one of my favourites dark sky places in Greece, Iria
Now, I am using two setups. The dark sky setup and my home setup. Both of them are using the iOptron CEM25EC that has a high precision optical encoder system and advanced control technology and the Japanese refractor, Takahashi FC-60CB with its dedicated reducer that lowers its focal ratio considerably to allow me to capture more photons faster.
My dark sky setup is using a special 36.3-megapixel Japanese astronomical camera from Nikon (D810A) that transmits light from the hydrogen-alpha spectral line at a rate that is four times higher than normal cameras, allowing me to capture faint details of nebulae that emit on that wavelength when I have access of a dark sky.
My home sky setup (aka 'The Light Pollution Fighter') is using a special Chinese astronomical CMOS monochrome camera from ZWO, the ASI 1600MM Pro USB3.0. With special astronomical 1.25' filters from Astrodon (USA) attached to a ZWO 8-position filter wheel, I can now capture specific light wavelengths (Ha, OIII, SII, LRGB, NII etc.) and combine them later on my computer. That gives me the flexibility of imaging from light polluted places, as most the imaging filters I am using cannot be affected by the light pollution.
My light-pollution fighting setup
My astronomical software of choice is PixInsight. I am often using Photoshop as well for final touches. The capturing software I am using are SharpCap and SGP Pro.