Hello

I've spent an inordinate amount of time reading posts and researching and am still not sure what to do.
My primary intention is to use the camera for portraits and I like selective focus which is what I like to do with the smaller formats I shoot. The look is different with an 8x10 in regard to the fall off. (Selective focus with a 300/5.6 with no distortion). So that is what drew me to the format. Than I looked at cost to purchase, shoot, weight, etc. My back is not the strongest so I am proceeding with caution

I'm wondering if I can replicate the look of an 8x10 shot wide open with a 300 5.6? What lens would I need to use in 4x5? It prob would not be the same as the tonality will differ, etc., but can I get close enough? My favorite focal length in 6x7 is 80mm for head and shoulders/ 80 in 2 1/4 and 50mm in 35mm). I would get a 210 in 4x5 as my only lens. In 8x10 I would get a 300 or slightly longer lens. I also like the idea of being able to use older vintage glass, that would be an option with the 8x10 mostly I think? Or at least for a better selection...I like to shoot head & shoulders. I like P. Roversi, Timothy Greenfield Sanders among many. I'm not looking for a clinical look or to be like them, but they do interesting work and inspire me.

In 8x10 I am considering a Sinar F2, Deardorff as I get find them used at a reasonable price point.
In 4x5... at field cameras: Wista DX, Wisner, Toyo 45A, Deardorff 4x5 Special

The trade offs for me. Is that I think the look of 8x10 is what I want, but at the expense of weight & mobility, film & processing expense. I like the idea of being able to do contacts (alternative processes) as well as scanning. I'm thinking a lot, and basically wonder if in the end maybe I'll get both formats...but I want to start with one and not go overboard either. I think I can handle the costs of the larger format as I would shoot less, but I would also learn less?

One last question, do you need more working distance form your model with 8x10 format vs with a 300mm vs a 150 in 4x5?

I'm in the predicament that there are a lot of paths possible. I've learned a lot from reading the board, but without actually shooting I'm in the dark, as ultimately it's a personal choice.

Thanks in advance,

Serge