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The more sharpening I use the stronget it gets.
By @Nicholas26902923jzk0
This kind of thing always boils down to some kind of moiré (interference patterns) between two sets of pixels - either image pixels : screen pixels, or original pixels : resampled pixels.
I see this is an extremely grainy image, which will exaggerate the effect, and obviously sharpening will exaggerate it further.
But please do as Per suggests and share the original if possible.
Thanks for sharing. I was curious so loaded your DNG in LrC 13.2. I use a calibrated Asus Pro Art monitor and can't see any moire/cross hatching in either LrC or in the exported TIFF when viewed in Windows Photo Viewer. I'm not sure if Photo Viewer is showing the TIFF file or embedded JPG preview. I mention this because depending on the viewer, you may be viewing the embedded JPG preview in the TIFF.
In case it makes a difference, here are the EXPORT settings I used
Here's a screen grab of approximately the same as you posted. This was taken on a cheap ACER secondary monitor but again, no moire.
I downloaded the dng and I do see it, same "grid" pattern - but the explanation is pretty obvious when you view it at 100%:
This isn't even a grayscale image, but essentially a binary bitmap with black and white pixels, but nothing in between.
So this is a display artifact caused by on-screen resampling. You need to view this at 100%, which represents one image pixel by exactly one physical screen pixel. That's the only way to get a correct view of the actual pixel structure.
If you need to scale/resample this, you are going to get into trouble no matter what. Any sharpening will make it a lot worse. This is just like halftone screen dots.
I can see a grid pattern when viewing the image at 100%, but it disappears when I turn sharpening off. 112 is an extremely high value, and masking is set to 0, which means that every little detail is sharpened.
Masking prevents flat areas (like the sky) from sharpening. Press the Option key while dragging the slider to see the effect. Black areas are protected, white areas are sharpened.
Always view the image at 100% when working with sharpening, noise, and other image detail.
This is the only view that shows you a true representation of the image – one image pixel is displayed using one screen pixel. Any other view will be inaccurate and misleading because the image has been scaled.
The image is very grainy, which is to be expected with a high resolution scan from a 35mm negative. But the grain is also extremely sharp, even when setting sharpening to 0.
I suspect that you are scanning with sharpening enabled in the Flex Color scanning software, which I don't recommend. I have an Imacon Flextight Precision II, and I always scan without sharpening.
For 35mm scans, I hardly use any sharpening at all at any stage, it usually makes the image look worse.
If I do decide to sharpen, I do it in LrC, or possibly Topaz Sharpen AI.
How large are you printing this image?
I would rescan the image with no sharpening, and then downsize (a copy of) the image to the required dimensions in Photoshop. The noise/grain will now be much easier to handle (try Luminance noise reduction), and you might even be able to apply some careful sharpening (use the Masking slider).
As a starting point, try Sharpening 40, Radius 0.5, Detail 25, Masking 50.
Thanks for all the information. Rescanning will be difficult, and I am not sure necessary. If I take the image that was corrected in LR with the 10 masks and export a tiff (or print) I see lines. If I make a virtual copy of the file and do a reset so that there are no masks and export a tiff, there are no lines even if I add sharpening. If I click off all the mass and export from the corrected version I still see lines. Very Odd. I guess I wilhave to go back to the original scan and try again.
By @Nicholas26902923jzk0
Your biggest problem is massive oversharpening, and rescanning without sharpening will make a huge difference. Don't just set sharpening to zero, turn it off completely by clicking the On/Off switch in the bottom right corner of the sharpening panel in Flex Color. If you just leave it at zero, some sharpening will still be applied.
(I know it's a drag if you have a SCSI scanner, the scan will take 15 minutes or more)
To illustrate some of the concerns here: On the right side of the picture below is a detail from my own scan from typical black-and-white negative film. If you compare the two, you can see that in the scan on the left, somehow many of the intermediate gray tones are missing, and there is a prominent stipple type of pattern. I also looked at a scan of a portrait on high contrast black-and-white slide film and even that isn’t as posterized as the image on the left.
When you re-scan the image, specifically check the bit depth setting, because scanning software terminology can be confusing and misunderstood. What you are looking for is to save a grayscale image, and you want to verify that whatever the setting is called, it’s saving at 8 bits per channel or 16 bits per channel. Some scanning software has an option labeled “black and white” which literally means black, white, and nothing in between (one bit per channel, or on/off). That 1 bit/channel setting is intended for text/line art documents, not photos, and if used on photos, the scanning software may translate gray shades into literal black and white by applying a dither pattern. The “cross hatching” you see does suggest a moiré pattern caused by pattern interference. I am able to see the moiré pattern in your original file on my display. (How visible a moiré pattern is depends on the difference between the frequencies of the pattern in the pixel grid of the image and the pattern in the pixel grid of the display or printer, so the pattern may be more visible or less visible depending on the display and printer.)
By the way, do you know what the film stock is? Is this the same type of film you’ve scanned before, or is this a special graphic arts type of black and white film?
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