Sharpening Drum Scans in Lightroom

[gcoates]

I've recently had a couple of 6x7 Velvia images drum scanned by a lab. The resulting files are roughly 11200x9200 pixels. I'm editing those images in Lightroom 6, and the sharpening options have me a bit baffled. The goal is to end up with good inkjet prints of these images. (I don't have a printer yet, so the lab will be handling the prints as well.) Would any of you be willing to share sharpening settings you use in similar situations?

 

[Adrian Gabor]

Sharpening is dependent on the size and resolution of the final print. There is no single setting or answer.

For scans I recommend the Smart Sharpening in Photoshop set to reduce Gaussian Blur as that is intended for scans. Start with something like radius set to 4 and ammount to 150% at that resolution.

 

[spijker]

Sharpening of film scans usually emphasizes the grain. So use the noise reduction in Lightroom to reduce the grain a bit first and then sharpen. Use the Option/ALT key to see where the sharpening is happening.

 

[jeffreyg]

As I understand sharpening you can't really sharpen an out of focus element if that is what you are after. Sharpening is a contrast function and makes an apparent sharpening appearance. If you over do it you get a halo look. Take your scans and experiment to see what happens. Try some of your Lightroom tools (I don't have Lightroom, I use PhotoShop). There are various plugins and stand-alones that have so called sharpening features. IMOP it's best to have what you want in the negative and tweak with software. It sounds like you are using very large files so check with the lab that is making the prints as they may be downsizing to print.
(note) I'm not a computer maven and mostly print analog but I do scan medium and large format negatives with my ancient Epson 4780 and print with an Epson 3880 and get excellent results up to my limit of 16x20.

http://www.jeffreyglasser.com/

 

[sepiareverb]

I find that fading the sharpening 25-50% after it is applied (Edit > Fade Sharpen in PS) can often give a very good result.

 

[Prof_Pixel]

I wrote an article for a magazine back in 2004 explaining unsharp masking which can be found at: http://www.frontiernet.net/~fshippey/articles/article4.pdf - yes, it's about digital USM, but I explain it in terms of the analog steps that must be taken. Note that it references the original article on the subject by J. Yule (PHOT. J., 84, 321 (1944))

 

[Saganich]

I wrote an article for a magazine back in 2004 explaining unsharp masking which can be found at: http://www.frontiernet.net/~fshippey/articles/article4.pdf - yes, it's about digital USM, but I explain it in terms of the analog steps that must be taken. Note that it references the original article on the subject by J. Yule (PHOT. J., 84, 321 (1944))

Enjoyed the article and learned a thing or two.

 

[Poisson Du Jour]

Velvia transparencies of 6x7 and 6x6 are my stock in trade so I am familiar with the subject, but I am baffled as to why there is a need for sharpening...
There should be no loss of sharpness through drum scanning, whether it is wet or dry. It is an inherently precise method of scanning and when carried out professionally there is no need to perform additional actions on the image other than profiling.

If a professional service level lab is handling your printing, get them to do the drum scan also so they can match the entire work flow to their printer without any hold ups from supplied scans. This is recommended particularly where giclee (inkjet) printing is carried out due to the nature of profiling for those printers as opposed to a different profiling process for traditional wet-LED process RA-4 printers (which will take just about any profile).

Desktop scanners usually lose considerable inherent image sharpness and USM replacement of 15% top 20% is common.

 

[ced]

My guess is that the scanner already applied USM, try looking at the image at 50% of final print size and if it looks sharp enough leave alone.