Monday, January 06, 2014

Testing a semi-pro transparency scanner

kw: product testing, product reviews, scanners, film scanners, slide scanners

I had promised myself a good film scanner once I got other year-end projects out of the way. I have the negatives from a couple hundred rolls of film plus a few hundred slides, from my pre-digital days. One of my brothers also has several thousand slides our father took. I ordered the scanner a few days after Christmas.

The first shipping day of the year, it arrived, an Epson Perfection V700. I have been reading and comparing reviews and tests and user articles for months, because a $600 investment is no small potatoes for me.

This is a product test, not a total review, so I'll forego a few things and get right to test results.

First, the negative I chose for these tests is a friend playing the banjo, about thirty years ago. I scanned in Professional Mode at 4800x4800 dpi. This first scan establishes a baseline. All options were turned off.

The color is too blue, but I am most interested in the film grain and dust that appear in closeups. You can see a large dust speck on the forehead and above the pegboard of the banjo. There is also a bit of lint on the collar, and others that we'll see in crops shown next:

Here, another piece of lint shows up at lower right, and two scratches, running nearly vertically, one at upper left and another to its right next to the bright curl of lint on the collar. There is also a large speck of dust near bottom center on the shirt pocket, left of the lint.

All of these images can be seen in a larger size (about twice) by clicking on them. At this size the film grain pretty well averages out.

First I turned on Unsharp Masking, a cool mathematical way to sharpen an image:


The primary effect is seen by looking at the banjo strings, which appear more distinct. However, the lint, dust and scratches are even more visible here. I think it better to concentrate on cleaning up the image. Sharpening can be done later.

To that end, for the next scan I turned on Grain Reduction. While I was at it, I also turned on Color Restore; it should not interfere with other functions:

Now the color is much better. A full size image also shows that the film grain has been reduced. But now it is time to test two methods of dealing with dust.

First, the software-only method, titled Dust Removal:

Clearly, Dust Removal doesn't touch lint or scratches. The speck of dust at lower center is still visible also, though perhaps a little less evident. We'll return to this. Note that I turned Color Restore off for this scan.

The second method is called Digital ICE, and uses two scans. One is infrared, and detects the dust, lint and scratches. Then they can be subtracted from the visible-light image by pasting nearby pixel patterns in. Here is the result:

This is marvelous! The dust and scratches are entirely gone, and I can see just slight hints of the lint. The drawback is that scanning takes more than twice as long.

Guess what I did next? I took the film holder out and used an optical brush to clean the negatives. Upon re-scan, the lint and dust are gone, though the scratches are still there.

Let's have a closer look at another area of the image before wrapping up. First, here is the other area of the scan with all options off. This is near the pegboard of the banjo:

In this area the film grain is more visible. This is a tighter crop also. One big dust speck and several smaller ones are evident.

Here is the effect of Grain Reduction:

To my eye, the graininess is reduced by half or better. The smaller dust grains are also less evident. This is simply a blur function.

Now for Dust Removal:

Now, that is nearly prefect. The algorithm finds dust specks in large smoothly colored areas and covers them over quite well. Too bad about the lint and scratches, though.

Here is the result of Digital ICE processing instead:

It is incredibly good. I can just see a tiny light spot where the largest dust mote had been. Digital ICE is clearly the best method for cleaning up images from imperfect film or slides. Of course, it is best to get them as clean as possible first, but that can't remove scratches.

The time spent to scan a roll of film is about an hour. Loading the film holders is somewhat finicky. People who use this scanner for production work (the ones that charge you about half a dollar per neg or slide) buy a second set of film and slide holders, for about $40. Once loaded and placed, scanning takes about a minute or so for a preview. Then you choose options, if you are in Professional Mode (and none other is worth using), and Scan.

To choose options, when the preview is showing you your thumbnails, be sure to hit the Select All button, unless you want to use different options for each image. You can choose them one by one by clicking in the image area of the thumbnail.

I was surprised that scanning is done image by image. I'd have thought the scanner could make a single pass and use software to pick it apart, but it scans each one, taking about a minute each, or a little less. With Digital ICE turned off, scanning a roll of 24 takes just over 20 minutes.

If you have turned on Digital Ice for any images, it scans each one a second time with the backlight turned off, using an IR source in its place. With the extra motion and resetting it does, it takes about 2½ minutes per image. That is a full hour just to scan a roll of 24 frames, or half an hour to scan 12 slides. That compares to over 20 minutes for the film and 11-12 minutes for slides, with Digital ICE turned off. In my estimation, the extra time is worth it.

Scanning film is a task I'll do while I have other stuff I can also do. I can get it going, do other stuff, and take a break from the other stuff to put the film away and load the next batch. I am really glad I got this scanner.

1 comment:

Polymath77 said...

See the post of Jan 9. Digital ICE takes longer than reported here.