I just joined UHH recently also. I’m using my dad’s old Canon T2i from 2010, the two kit lenses it came with, a Tokina telephoto up to 400mm, and an Olympus 50mm 1.8 lens. That’s enough for me to work with as I continue to learn the art, and I’ve been surprised with the results as I continue to improve with the older technology. One of these days I’ll invest in something more advanced for low light and Milky Way pics but for now I’m enjoying the journey. Thanks to the UHH community for supportive and Honest feedback that can only come from photographers.

When I was just getting into digital from film many years ago, I thought the same thing - after shooting 400 ASA film, why would anyone need fast lenses with DSLRs now good to ISO 3200 or higher? I said as much to a pro at the camera store who knew better, but was kind enough (or smart enough) not to argue. Now I know better. Since then I’ve learned how much subject isolation matters and how much difference there is in IQ when you can shoot that indoor wedding or sports or candids with no flash at ISO 3200 instead of 12,800 (2 stops). I also noticed how that pro was often shooting fast primes instead of zooms. Now I understand that as well. Let me provide an example. Available light, 50 mm f2 wide open at ISO 6400 on a crop Fuji SOOC. Can’t do this at f4 (or even f2.8)

The main reason from the beginning was during the film era you had a fixed ASA or speed of the film now ISO. Most of the best films were very low like ASA 25 and 64 these being the Famous Kodachrome . To shoot these films you needed a fast aperture just to avoid using a tripod . This style of shooting for early morning light and evening capture require high F stops for depth of field in landscapes and shutter speeds of 1/4 a second or 1 sec in some cases . In most cameras the lens remains wide open till till moment of capture when the lens shuts down to the predetermined aperture . Most lenses in medium format cameras and Large format cameras used leaf shutters today focal plane and electronic shutters make things much easier . So now lenses with fast apertures still make it easier to focus in low light situations because the more you shoot at base ISO the higher the dynamic range any camera can aquire . My Camera a Nikon D810 has 14.8 stops of dynamic range at base ISO 64 allowing Me to no longer shoot 3 frames to capture a HDR style image by just using one image and recovering the shadows without a penalty of noise . Same with the D850... So we will always covet fast lenses . For BIF shooting Fast apertures allow low light fast lens focus acquisitions of the target and tracking ability of even the eyes without it the lens hunts for focus lock .P.S. On Many Cameras today You lose auto focus points when the lens is a f5.6 verses a f4 or faster limiting to the central region of your view finder.