Using Lightroom with scanned negatives...

[dreed]

For those that have scanned negatives to a digital file and decided to process them in LR, are there any do's and dont's?

Or is it better to just avoid LR and do everything in PS?

Whilst some of the controls seem to work "normally", others (such as "Luminance") have radically different behavior. And by radical, see what I mean with the two attachments below. They're roughly the same section of sky (that had some cloud in it.) The "after" image is -100 Blue Luminance.

[Slobodan Blagojevic]

What exactly is the issue with the before/after example? Looks like what one is supposed to get when drastically darkening one color.

[AFairley]

Unless I am stitching I do everything in LR.

[George Marinos]

It seems normal to me.If you decrease the luminance in the blues then the blue particles in the film emulsion get darker and you get more granularity. You can work very well with Lr ,but you need to choose carefully the right tools.I use always Lr to edit my Imacon 949 scans...

[razrblck]

When you don't have raw files (basically working with jpg or tiff files), Lightroom defaults to no color noise correction, while the default for raw is 25 in color noise correction (on top of the camera profile corrections). What I can clearly see in the first picture is a lot of color noise with all the magenta and green dots, this is why decreasing the luminance of only one color will not affect the others and make noise stand out even more.

[JoachimStrobel]

I believe the effect that you see results from overly sharp scanned negatives. Once you go above 3000 horizontal pixels, then you scan grains and also the void between grains. Then it is easy to over sharpen them in one way or the other. Some people say, DXO does a good job with its simple noise algorithm.  I try this out at the moment: I processed 400 negatives in LR for a photo book. Exported them as JPEG and send them away. The photos in the book looked ugly. I got in an argument with the print company. They said that LR over sharpens the JPEG (true, I had LR on the lowest sharpen level while exporting) and that their own algorithm does "the rest". It was my fifth photo book project with the same company, previously I did not process the scans or had processed raws. They allowed me to send the photo book back and will print a new one with reprocessed photots. I am busy now developing the same scans in DXO. I hope that it gets better.

[AFairley]

And then there is grain aliasing....  http://www.photoscientia.co.uk/Grain.htm  (I don't know how accurate this article is.)

[JoachimStrobel]

.... thanks, that was interesting to read. Lowering the micorcontrast a bit while smoohing a bit helps. And keeping the fingers off the de-haze slider.