Thoughts Upon Scanning

It generally starts with an e-mail that goes "I have been shooting pictures for many years, and now I would like to scan them into digital form. I have a mix of slides, negatives of various sizes and family prints - maybe 30,000 in all. What is the most efficient way I can do this?"

First get organized.

This will save months of work, even though it means a bit of drudgery at the beginning.

Film is an excellent storage medium for photographs as long as the film is filed in easily accessible archival sleeve pages. Buy a bunch of three ring binders for organizing your film, along with the necessary pages.

Two additional items will make life a whole lot easier. Buy a light box large enough to be able to easily see a full page of film strips. Second, select a space with enough horizontal surfaces and buy an air cleaner that will keep it reasonably dust free. Anyone involved with darkroom work wages an unremitting battle against dust.

Now spend some time thinking about how you want to have your images filed - both in the binders and on your drive. Then sleeve your film in the way you have chosen.

As you are doing this, have a pad of tiny Post-It Notes at hand and use them to flag your best and most significant exposures. Be selective. These are the images you plan to access frequently. If you are looking at a series of related exposures, only flag the most meaningful. If there are two that are almost the same, pick the best one. At this point, avoid flagging so many that you are overwhelmed.

While you are going through the sorting and filing process, be thinking of exactly why you are doing this. If you just got a scanner and want something to do with it, you will quickly become bored and abandon the project. Learning to produce good scans takes time and work. Is the goal a web site? Slide shows? A DVD for the family to play on TVs? How many prints will you actually make?

Scan not for the resolution of the input device - the scanner - but rather for the needs of the output device, be it the screen, projector or printer.

If you are aiming mostly at screen presentations, there is no need to scan at high resolution. Most web pictures are a maximum of 640 x 480. People still use dial-ups and I have a topic with 800 x 600 pictures and I get complaints. Digital projectors with a resolution of over 1280 x 1024 are still quite rare and expensive, so for a slide show, that is about all the resolution you need. Even with HDTV coming on, the highest resolution it can show is 1920 x 1080. Anything beyond is thrown away.

What about those intended for prints?

A while back I did some tests of print resolutions, I took a top quality medium format negative and scanned it to 5x7 print size, first at 240 dpi and second at 360 dpi. I printed these side by side on a single sheet of premium glossy paper. They were shown to a lot of people under widely varying light conditions. Perhaps 20% said they could see some difference on very close inspection, but not one person would venture which print was better.

I also did a pair at 300 dpi and at 150 dpi. At reading distance, the 300 dpi print was clearly superior. At arm's length, they became somewhat ambiguous, and it took a bit of concentration to identify which was which. A short distance farther and they looked identical.

Just because your scanner claims to have an optical resolution of 6400 dpi, does not mean that you must use it. It is simply pointless to scan to some exaggerated resolution and then throw away most of it, since it is not usable.

OK, your film is sleeved and filed, your best photographs are flagged. You clearly know your goals of how the images will be used.

Time to begin scanning.

If you are just entering the digital darkroom for the first time, expect to spend considerable time acquiring skills to do this. Realize as well, that the learning process never ends. You may well be pleased with your initial results, only to find a year later, that you want to redo everything.

That is natural. As your skill level rises, so will your expectations. If you want a job done quickly, hire a beginner. If you want it done well, hire a master - and expect it to take a lot longer.

Start with the images you have flagged - only. You might want to move the pages with flags to the front of the binder for easy access or designate a separate binder for these - the cream of the crop.

Working with these images is like visiting with long lost friends. Such pleasure seeing them come up on the screen. They are the incentive to learn, and these may be the only ones you really need to scan. Film, well filed and stored, is an excellent medium for preserving pictures - as I said above. There is no reason to scan images you will never access.

If there is a family celebration in the offing, it is a good time to go through the files again and put together a presentation. By waiting until there is a reason, you can fine tune the scans to that presentation. You waste neither time, nor drive space and produce the very finest product.

You now have reasonable sized files on your drive, organized for easy access. You have no clutter of nearly identical images, blurred images, badly exposed images and all the other things that detract from a photograph. You have cut the 30,000 images down to perhaps a thousand, and that is doable. Since you have the scanner and the skills, you want to revisit the film at leisure any time.



How I scan

My film is stored in binders as above, and I have a separate binder that holds all my favorite images. If that works for you, do it.

Much of my photography was done with medium-format cameras, so that was the prime consideration in buying a scanner. I could not justify the price of a dedicated medium-format film scanner, and at the time the Epson 4870 was getting good reviews. My expectations were low, but I bought it anyway. My first print made me a true believer. It was the equal to any I have ever done in the fume-room and as good as any I have ever received from a professional custom photo lab.

I expect that there is not much difference between high-end flatbeds, and there are happy users for all of them. If I were to replace my scanner, I would go with another Epson, since I am familiar with the software and overall operation of the scanner. Had I started with a Canon, HP, Microtek or whatever else, I would go with a newer model of that one. If a device works satisfactorily, I see no need to learn a new one just to be different.

I scan directly into Photoshop CS2, using EpsonScan. Of all the scanning programs I have looked at, it gets in the way the least. What I demand in a scanning program, is to deliver a good scan that I can fine tune in Photoshop with a minimum of fussing with it.

In the past,when scanners were just 24-bit, low resolution and computers were slow, the wisdom was to do most of the processing in the scanning software. Now the tools in Photoshop are far more comfortable to use and provide excellent results with the scanning software being used for capture. I click on auto to get a decent starting colour balance, and manually set my black and white points for more detail than I may need. The final image is created from this in Photoshop.

I scan for the purpose the image is intended to do. While I don't buy that interpolating will ruin the image, I scan to the exact size I need. EpsonScan has a dropdown menu with all common sizes of paper and web images. It also will let you select the exact dimensions in metric, inches or pixels. If I am going to make an 8x10 print at 240 dpi, those are the selections I make. It will only let me crop the image to fit. When I tell Photoshop to "Print", the image will perfectly fit the paper with no resizing at all.

EpsonScan supports batch scanning, with individual settings for each image, so I could theoretically load in 24 negatives, and set it scan them while I sleep. It also supports DigitalICE which is a combination of hardware and software built into my scanner that does a very nice job of removing the images of dust particles and scratches at a great penalty in time. If there is little dust and no scratches, it is probably faster to use the clone tool and healing brush.

For overnight batch scanning, DigitalICE is wonderful. If you have an old computer, consider hauling it out of the attic and making it a dedicated acquisition machine for batch scanning. Set up the film with the settings and just walk away and do something else while it scans. A network card makes access to the scans from your main machine easy. I have a somewhat elderly machine that serves as my video, audio and image acquisition platform. It spends most of its time working - unattended.

If your time has no value and you really like dealing with obscure icons and hidden menus, Epson also bundles Silverfast software. Some people adore it, and if you love to fiddle within a Byzantine and counterintuitive interface, by all means try it. Both will give excellent results.


So what about scanning all my images at maximum resolution?

The initial question was aimed at transforming a huge number of analogue images into their best digital equivalents. What about scanning everything with the maximum amount of information that one can extract from an image?

Scanning is work. If you are skilled, you may be able to do a scan, process it and save it to your hard drive on average of one every 15 minutes. Do the math. Four scans an hour is 160 in a 40-hour workweek. This means 187.5 weeks to finish the job. That is over three and a half years, without vacations. Are you still enthusiastic?

To get usable scans, requires skill in scanning and skill in processing. Neither scanner nor image processing software has an automatic "Create Masterpiece" button. Most have auto-features, but often they produce such an awful image, that you spend much more time having to manually fix it. With some images they may save a bit of effort, but will never be able to read your mind and produce the image you visualize.

What kind of a scanner do I need?

Viewed at 100% on a computer screen, the output of a scanner costing six to 20 times as much is evident. With a bit of simple image processing, most of the difference vanishes. When concentrated to 240 to 360 dpi in a print, it would take a very keen eye to discern any difference.

There will be those who will say that for film, you should by a drum scanner only. Well fine, if you are shooting for big budget corporate advertising posters. The learning curve is formidable and the device is not easy to use. Film is mounted on the drum using highly volatile scanning fluids.

Others will tell you that flatbeds simply will not do the job. This was true five years ago, but today, dedicated scanners may still have an edge, but not enough to justify the price if you are doing a personal collection of images for your own and your family's use. Flatbeds have the advantage of being able to scan anything including the cat. Just don't close the cover tightly!

There is now a follow-up question "Epson just announced that the new V700 series of scanners is capable of 6400 dpi. I was planning on a 4800 dpi scanner. How much better is 6400?"

Even Epson claims the figure is a mix of optical, mechanical and software factors. Simply, there is no standard for measuring and comparing scanners. Within Epson's line or Canon's line or HP's line, consider resolution to be more of a model number than an absolute value. If the company has a 2400 dpi model and a 4800 dpi model, you can be pretty sure that the 4800 dpi model has considerably more resolution than its little brother.

"Then what resolution do I need? I want to get everything out of my film."

The reply is "What are you going to do with the scans?"

Reply, "I want to archive them and don't want to throw anything away. I guess I will make prints of some of them."

If you have a letter sized printer, chances are you will see no improvement printing with a resolution above 300 dpi. At 300 dpi, a letter-sized borderless print needs exactly a 3300 x 2550 pixel image - no more.

If you were to scan a 35mm frame at 6400 dpi, you would get a file that is about 6400 x 9600 pixels. You would be throwing away 53,190,000 pixels every time you make a letter-size print. There is simply no way for the printer to use all those pixels.

Worse, you would be dealing with nearly a 350MB image if you scanned at a depth of 48-bits.

Big images are painfully slow to process, even on a high-end machine. Why scan at 48-bit? Substantial corrections can be done to the image without noticeable harm. With 24-bit you have only 256 steps between black and white in each of the three (red, green and blue) channels. With 48-bit this increases to 65536 steps. Even with heavy processing, gradients remain smooth in 48-bit.

If you own stock in a hard-drive maker, then I suppose that 350MB images seem rather nice. Three of them overflow a gigabyte of storage, and with 30,000 we begin to talk in terabytes.

How about DVDs? Well you can get at least a dozen on a DVD, so 30,000 images would only require something between 2000 and 2500 discs. Burning four an hour would take you an additional 500 hours not counting some means of identifying what scan is on what disc and how to find it. Are you still enthusiastic?

Consider how many of the images you will actually access, and consider the amount of space the others are hogging. Is it not better to just scan the ones you will be using on a daily basis, and scan the others as needed? Even though it means taking a break to find the film and do the scan, selective scanning and scanning on demand will save years of work and terabytes of storage.

©2006 Larry N.Bolch