Is Canon RF 15-35mm F2.8 unavoidable for interior/architecture photography?

atolk wrote:

I get calls from an architecture design studio to shoot interiors and exteriors of their buildings. So far, I have been getting by with the EF 24-105mm F4 on a Canon 6D and now R6. I get good results, but was thinking about making my job easier and results more impressive.

For "architecture photography" everyone recommends tilt-shift lenses, which are expensive and prime. For "interior photography", the top recommendation is the RF 15-35mm F2.8 at $2,399. The zoom range is not that great, but I feel the 15mm wide end of the zoom is necessary as I am struggling to get tight spaces like bathrooms and meeting rooms in at 24mm.

F2.8 for interiors? Probably an overkill, lets more light in, but we are not looking for any artistic shallow DoF effects.

You should never be using f2.8 for these kinds of shots.  There's no point.  You are on a tripod and you want the best quality and deepest DOF.  f2.8 is very good on modern glass, but f8 is always still a little better.

Of course at 15mm, the scene should be mostly in focus at any aperture.

Don't be so sure.   Say you are in a room that is 20 feet across and you focus on the back wall.   Your DOF won't start until 6 feet away from the camera.  That could make for plenty of near details that are blurry.  Even if you carefully pick out the hyperfocal distance, you still don't have DOF starting until 4.4ft.

But if you just went with f11, regular focus is at 2ft and hyperfocal is 1ft to infinity.   So everything really will be in focus.

Is there a lens with a better zoom range, or cheaper, or in any way a better interior/architecture lens than the subject?

Cheaper, yes.   Look to EF.  16-35mm F4L,  Tamron 17-35mm f2.8-4.   Stopped down and on a tripod, the image quality is close enough that nobody will ever tell the difference.  16-35mm is honestly probably a hair better than the 14-35 anyway.

Wide is nice, but remember the wider you go, the more stretched the edges get.  I wouldn't sweat the difference between 14 and 17mm, as I think you can make any of those work and they are all so much wider than the 24-105.

Would I go for a manual focus lens? Maybe. The scene is not going anywhere. But the touch AF on R6 is a godsend when the camera is tripod mounted.

Thanks!

If this is a new highly paid business opportunity for you, T/S lenses may be a good idea, especially for multi-story buildings and interiors.   It helps control that look where the building looks like it is leaning back as it gets taller.