ive been shooting the night sky for ages now and over the years ive realized that while 20mm is great, sometimes you just need that ultra-wide perspective to really capture the scale of the galactic core. if your budget allows, the Sony FE 14mm f/1.8 GM is the holy grail. in my experience, the sharpness even at the very edges is just insane and it barely has any coma to speak of. if you want a zoom instead, the Sigma 14-24mm f/2.8 DG DN Art is a solid alternative that stays incredibly sharp across the range. quick tip for the a7IV: dont trust the old 500 rule for shutter speed anymore since the sensor resolution is so high. look up the NPF rule instead to avoid those tiny star trails that ruin a clean look. also, always use focus magnification on a bright star to nail your focus manually... hitting that sweet spot makes or breaks the shot. let me know if you need help with the specific internal settings!

Honestly, for the a7IV, you really want to prioritize lenses that handle sagittal coma flare well, as that is what turns stars into birds in the corners of your frame. From a technical standpoint, the Sony FE 20mm f/1.8 G is basically the gold standard for price-to-performance right now. It is incredibly sharp across the frame and the f/1.8 aperture lets in a ton of light while keeping the ISO at a manageable level to preserve dynamic range. If you need a wider field of view for the core of the Milky Way, the Sony FE 14mm f/1.8 GM is the professional choice. It features specialized XA elements that practically eliminate chromatic aberration. I always suggest checking for robust weather sealing too because dew buildup is a real reliability risk during long night sessions. A few technical tips to consider:

• Use the NPF rule instead of the old Rule of 500 for the a7IV because of the 33MP sensor density.
• Always use manual focus and magnify a bright star to 10x to ensure pin-sharp results.
• Turn off Long Exposure Noise Reduction if you plan on stacking images in post-processing.
• Invest in a reliable lens heater to prevent condensation on the front element. The Sony FE 24mm f/1.4 GM is also excellent if you prefer a tighter composition, tho it can be a bit narrow for some foreground landscapes. Just be sure to test your copy for centering issues before the return window closes, as quality control can vary even on high-end glass. It works well tho.