Architecture w/o People - reciprocity/development corrections

[Fermat]

Hi all
I have a project in mind re taking pictures of some buildings in the village where I grew up but I do not want people in.
I think I can use a ND filter to use a long exposure.
I use the film Ilford Delta100 or Kodak TmY 4x5".
Is there any practical guide to correct the time exposure and time development?
Thanks

Inviato dal mio RMX3241 utilizzando Tapatalk

[PatrickMarq]

You have the reciprocity timer app/website
But people still needs to move a bit around, or you have ‘ghosts’

[Joe O'Hara]

Have you thought about working in first light, just after sunrise? Few people are up and about them. Your project
makes me think of Eugene Atget (1857-1927), one of my very favorite photographers. People rarely figure in his
pictures.

[Mark Sampson]

I was thinking the same thing. Too few of us want to get up that early (I know I don't).
Both Ilford and Kodak have published reciprocity-failure charts for their films; they should get you close.
And remember Daguerre's street scene, where the only person visible is a man getting his boots shined.

[Vaughn]

Ten minutes and still had a couple people 'ghost' on me (sitting while waiting for a bus)...

A few buses showed up...and a few headlights.

Not correcting for reciprocity failure can help pump up contrast if needed. If you have some small areas that will drop to pure black if uncorrected in a low contrast scene, let them -- then decide to develop normally, or to boost contrast even more by extra development.
Or give the scene the extra exposure to keep that shadow detail, and decide where you want to take the highlights, rather than the rote "reduce development" advice.

This allows reciprocity failure become a tool for lowering low-end shadow exposure relative to the rest of the scene.

[Fermat]

Thanks to everyone for the valuable comments.

Inviato dal mio RMX3241 utilizzando Tapatalk

[Vaughan]

How To Photograph Crowds Like Alexey Titarenko

[Doremus Scudder]

I've done a bit of this. I like about 20-30 minutes of total exposure time; that's after figuring in reciprocity failure corrections.

A 10-stop ND filter is what I use. If people stand too long in one place or something bright or with a light source comes by (think headlights, even from a bicycle) then they could show up in the image. I avoid this by covering the lens when people aren't moving around, etc. All that matters is the total exposure; you can achieve that with multiple exposure of one to several minutes.

Here's a reciprocity failure adjustment table for Delta and TMax films that I have from a photo-astronomy website. I haven't tested the longer times, but they should get you in the ballpark. Keep in mind that the overexposing a 20-minute exposure by 10 minutes, when you figure in everything, is only about 1/3-stop more. Err on the side of overexposure when in doubt.

Indicated Exposure ----- Actual Exposure
2 sec ---------------------- 2.5 sec
5 sec ---------------------- 7 sec
10 sec -------------------- 15 sec
15 sec -------------------- 25 sec
20 sec -------------------- 35 sec
30 sec -------------------- 50 sec
1 min --------------------- 2 min
2 min --------------------- 4.5 min
4 min -------------------- 10 min
10 min ------------------- 30 min
20 min ------------------- 1 hr. 10 min
1 hr. --------------------- 3 hr.

Have fun!

Doremus