Film density correction

[marameo]

Hi,

when you expose neg color color film say 3-4 stops over and ask the lab to color- and density correct the scan, what do they actually do?

Thanks

 

[mfogiel]

Nothing. They develop normally and scan normally. The scanner adjusts to higher density by itself.

 

[ray*j*gun]

Well yes if its with-in the range of the equipment. There are parameters to the adjustments and unless its a small shop (read custom) it will scan up to the limits and that will be what you get.

 

[ChrisLivsey]

If they are a decent lab they reflect what the film records

http://ukfilmlab.com/2014/04/24/film-stock-and-exposure-comparisons-kodak-portra-and-fuji/

If you tell them to "correct" to something else they will, within the parameters of what is possible.

 

[marameo]

Is that basically the auto option for levels and curves or something more precise like set the white and black point thru the eyedropper tools in lab mode?

 

[marameo]

BTW: have you ever tried this method to remove the colour casts in the neutrals (especially true with slide films where almost always too much color is put in the neutrals and blacks)? Create a curve as an adjustment layer in l*a*b mode and set the following points in the A and B channel(0,0)(4,0)(8,0)(12,12)(16,16)(20,20)(24,24) and their negatives. I also set the white and black points in l*a*b mode and the overall image quality improved.

 

[marameo]

Is that basically the auto option for levels and curves or something more precise like set the white and black point thru the eyedropper tools in lab mode?

I think I understand how to density correct an overexposed color negative; the following is Portra 800 at 50 ISO. I used lab mode to boost the color and set b/w points.