Epson v850 scanning artefacts?

[:: Mark]

I have been pixel-peeping my scans again, and am seeing some unwanted artefacts that show up along horizontal edges in an image.

The crop below shows an area of 35mm HP5+ negative. The left image was scanned with an aging Plustek 7600i (Vuescan), and the right with an Epson V850 (Epson Scan). Both scans were at 3200dpi.

Any ideas what could be causing the zig-zag effect or how to reduce it? It seems to be always present to some degree, but some scans/negatives are worse than others...

 

[Scapevision]

Looks like you used DigitalICE on a b&w negative

 

[xvvvz]

I too was wondering about your settings for ICE, sharpening, moire removal, "dust and scratches" plugin, etc. Please tell us your exact software settings.

Doug

 

[:: Mark]

In Epson Scan, ICE was disabled, as was sharpening and and all other corrections. I used 16 bit grayscale mode, with TIFF output and default settings for the curves etc. The image was sharpened slightly in C1, which makes the effect more obvious.

This was from a batch of 18 frames. All of them have the effect, but on most it is much more difficult to see.

Is it possible that the Epson software sometimes tries to do multiple passes and something in alignment fails? I might retry with vuescan - I tend to avoid it with the flatbed as aligning the frames is a pain.

 

[Scapevision]

Epson Software doesn't do multipass as far as I know. There is no multipass setting.

 

[Greyscale]

Grain aliasing? Try scanning at a different resolution or turning grain reduction on.

 

[BernardL]

Grain aliasing, ICE artifacts, etc. None would give that characteristic look of improperly de-interlaced video. The sensor of the V700 (I assume the V800 is similar) has staggered rows of pixels, a diamond pattern if you prefer. Looks to me like Epson Scan or the scanner's firmware, for some reason, do not handle properly the pixel pattern to generate a square array.

Since you have Vuescan, I suggest you try using it with your V850 (already suggested by ::Mark)

 

[williaty]

I've an V850 as well and I've seen that same sort of artifact when scanning with SilverFast Ai Studio 8.

 

[:: Mark]

I tried Vuescan, and it gives the same effect. However, if you use Vuescan with the multipass option, then the resulting slight blurring masks the effect.

The following are crops for (left to right):

- V850 with Epson Scan
- V850 with Vuescan (single pass)
- V850 with Vuescan (three passes)
- Plustek 7600i with Vuescan (single pass)

So unfortuantely, it is not an Epson Scan software problem...

It looks as if adjacent rows appear to be offset by ~3 to 4 pixels by the V850. Furthermore, the effect is much worse for film frames near the front of the scanner than it is for frames near the back, and the shift is large enough to significantly degrade the scan quality in one direction (probably giving about 1000dpi effective vertically and 2500 dpi horizontally for the worst affected frames).

Using multi-pass scanning in Vuescan helps reduce the problem, but probably only because it is slightly blurring the image due to alignment errors between the passes.

The more that I use it, the less happy I am with my v850. Aside from these problems, there are the useless perspex backed film holders that act as dust magnets and which have height adjusters that never stay in place. I might look at another semi-automatic scanner specifically for 35mm film (Plustek 120 or Reflecta RPS 10M?).

More positively (and surprisingly), the Vuescan RAW TIFF output looks sharper than that from Epson Scan - even though all corrections were supposedly disabled.

 

[BernardL]

Too bad! Out of warranty? That would be a clear case for a warranty claim.
A (very) long shot: try changing the USB cable. I know.. but that advice from Ed Hamrick solved for me another issue that I would have bet was unrelated.

 

[p.giannakis]

What operating system are you using on your computer?
I had a similar problem with my Canon 8600F which was creating vertical lines and it was the driver. Once i uninstalled the driver and installed an older version of it for windows 7, it worked well.

 

[DNG]

If you are scanning a B&W negative in color mode, try 16bit B&W mode....
Digital Ice is not available in that mode with Epson Scan.

I have scanned plenty of Color Slides and Negatives with my V700... never saw this when I edited in Lr.

As suggested, maybe Epson has a updated driver.

 

[:: Mark]

Well, it is not the driver. It turns out that I did have an older version installed, but updating did not change anything (I am on macOS 10.11.5).

I ran some scan tests at 6400dpi and they show the same pattern, again with alternating rows that are one pixel wide. You can load the images in to Photoshop as two layers with interlace masks, and if you slightly shift one of the images about 2 pixels it brings everything in to alignment. Unfortunately this is very tedious to do, not least because the amount of shift varies from image to image.

But fortunately, simple bicubic downsampling from 6400dpi to 3200dpi appears to do a good job of masking the problem without much loss of resolution:

The left image is the native 3200dpi crop, and the right the downsampled version, which is way way better to my eyes and similar to scans that for whatever reason are not affected by the interlacing problem.

Fortunately, I already pass the scans through PS to convert the TIFF format in to something that Capture One is happy with, and so scanning at higher resolution and adding downsampling to the batch processing is not a major problem.

I have had to learn more about Photoshop since I started shooting film again than I ever needed with digital :bang:

 

[xvvvz]

I would contact Epson support and show them your test results, especially if you are still under warranty. You should not have to do that workaround. First tier support will be worthless but ride it out so they will pass you on to second tier.

Doug

 

[Skannaaja]

I have this same problem with my Epson V850 Pro scanner, when I try scan films to TIFF format with 3600 or 4800 dpi. I have tested Windows 7 and Windows 10 operating systems and various scan softwares (Vuescan, Epson Scan 1, Epson Scan 2 and Silverfast) and still same zig-zag effect.

But if I scan to JPEG format or 2400 dpi TIFF then scanner works fine.

I have contacted to Epson Support (Customer Service) and they said that scanner is working properly and they refuse to warrantly repair the scanner. They said that problem may be the film or image viewing progam, I think that their claims cannot be true.

 

[JeffS7444]

I occasionally see artifacts like that with my Epson V700 scans if there is any vibration or disturbance while the scan is in progress.

 

[Pál_K]

With my V800, scanning either B&W or color to .jpg format, mostly at 2400 dpi but occasionally 3200 and 4800, I have never seen this artifact.

On some occasions dust removal or Digital ICE has produced a weird object. Once there were some distant poles with light fixtures atop them (i.e. such as a street light) and these were transformed into odd gray pixilated parallelograms.

 

[Doug]

I occasionally see artifacts like that with my Epson V700 scans if there is any vibration or disturbance while the scan is in progress.

Vibration seems a useful possibility to investigate...

 

[Skannaaja]

Vibration seems a useful possibility to investigate...

When scanning with high resolutien the zig-zag effect lines may be created by stepping motor of the scanner.
If I use unsharp mask then the effect will be more terrible/visible.

So I can't recommend to use Epson scanners if you want scan your photos to TIFF-format with high resolution.

 

[albireo]

Was your V800 moved around or transported without engaging the transport lock button on the back at any point during its lifetime?

I've seen similar artefacts on poorly handled second hand units which were bumped around by the courier during delivery.