Scanning negs, tweaking and printing

[Richard Littlewood]

Later this year I'm planning on getting some 40" colour prints made, starting from 5x4" NPS colour negs. Maybe up to 6 images in total. Conventional printing seems to be slipping away round these parts for big prints, so I thought give that digital stuff a go - it seems labs consider nothing to be a problem where digital is concerned.
What I plan doing is having the lab scan the negs (about 120mb) then I'll slip the images in to photoshop to do the required tweaking. The alterations will probably only consist of altering density, colour balance, darkening of skies and other bits, spotting out, and possibly a few other 'balancing' effects.
The only images I have worked on so far in Photoshop (6) have all been in B+W (I've done quite a lot) so the colour aspect is all new. Given that the monitor is calibrated OK, and the computer can handle the file size, has any one had any experience tweaking digitized images in this way? The scans are going to be quite expensive, and I don't want to make a hash of it!

[Doug Dolde]

Some good tips here

http://www.pixelgenius.com/tipsandtechniques.html

[Ralph Barker]

I'd suggest discussing the scanning and tweaking effort with the lab that you're going to have do the prints. First, make sure that the scans you're planning are sufficient for their process, and discuss how their system is profiled/calibrated. You may need to coordinate the color profile and do test prints (smaller ones?) to zero in on the color balance, etc. you want in the final prints.

[Graeme Hird]

120mb files seem a little small for 40" prints, though I haven't done the maths to work that out. I would expect the files to be around 300mb minimum.

[Bruce Watson]

Just about everyone who uses Photoshop for images has experience tweaking digitized images in this way, yes. Search for Photoshop workflows. You should find a lot of information and a lot of conflicting advice. This just means that there are many paths.

Like Graeme, I think that 120 MB is probably a rather small file for this. If you are getting an 8 bit scan, that's still only 141 dpi for your 40x50 inch print. I recommend for best results that you scan at the resolution of the output device. An Epson 9x00 printer would want 360 dpi, for example. Most Lightjets want 305dpi IIRC. Of course, it depends on the image, your lab, your expectations... so YMMV.

[John Berry ( Roadkill )]

I scan my negs all in 16 bit. Epson 2450. 4x5 at 2400 ppi. I always archive at this res. It may seem like a lot, but it's easier to down res than up res. I prefer to have the working image 4 times the size of the final image. Lotsa room to mangle pixels. My histogram can beat up your histogram. LOL I agree 120 meg is too small. Mine are 180 mono and 550 color. At 360 dpi that is 6.6x enlargement. You might print at lower dpi but I don't. Remember ALL printers print at 8 bit resolution. 256 shades. That is why I am now filling trays again after 4 yrs doing nothing but digital.

[Richard Littlewood]

OOPS! Yes I should have put a higher mb number in there not 120 (thinking of my B+W process) LF photographers always err on the big side, but commercial labs do tend to view anything digital as the right way. Not long ago I photographed some still life stuff on NPS in available light on 5x4. Exposure in camera was anything up to 50 seconds. I had some 40" prints made by the lab using a proper darkroom. These prints were beautiful, soft gradation, full of tones, silky contrast etc. I did these over an 8 month period. During that time the lab went digital and (without telling me) they made Lambda prints instead. I dont know how they processed the negs, but the prints were different. They looked cruder and somehow false with all the previous qualities gone. That was about a year ago, I'll give it another shot though with some landscape stuff. Fingers crossed.

[Bruce Watson]

Richard,

Scanning at too low a resolution will do that to a print. The labs will normally err on low resolution side for scanning for two reasons - first, they don't want to discourage their customers with outrageous scan charges, and second because they don't want to deal with really large files.

I've got my own drum scanner (I finished repairs yesterday - yea!) and do my own drum scanning and printing. I've made a few large prints (1.0 x 1.25 m) from 4x5 Tri-X originals, so I have a feeling for what you are trying to do maybe. I've been scanning for maximum print quality, and I've gotten prints that are the beautiful soft gradation, silky smooth, highly detailed prints you seem to want. I did it by scanning at full printer resolution. For me, that's an 11x enlargement at 360dpi, in 16 bit grayscale. A file that's around 500MB. The one color one I did this way was 1.5GB (yes, I'm pining away for 64bit Photoshop).

Is this overkill? Maybe. But I do love the look on people's faces when they see a print done like this - nose sharp and silky smooth. All I'm saying is, it's possible to get there from here. It may not be easy or cheap, but it is really good.

[Bill Brady]

Richard,

Did you send a neg to the printer (lab) or a file?

If a file, did you send in CMYK or RGB?

Thanks guys, a great thread!

[Richard Littlewood]

I sent a neg. I'm sure Bruce is right. That was then, this is now!. I'ts only when you have a good look at digitally produced stuff do you realise it is so easy to take a backward step with the end results, and how much potential there is in a negative - well some of them - about 10% for me. Could do with one of those 1.8 inch LCD screens to 'edit' on - no more 10% (only joking!)