Tuesday, January 26, 2016

Scanning Film

Scanning Film

This is my "getting started" article on scanning film to digital files.  It looks at major factors, methods and trade-offs.

Why Scan Film?

A purist would suggest that the best way to use film is creating a print with an enlarger.  In certain respects, they are correct.  In skilled hands, gelatin silver prints are incomparable in their quality and beauty.

That said, there are practical considerations that benefit scanning to digital:
  • Sharing.  In digital form, it's easy to share your film photos with many people
  • Security.  Your original negatives are one-of-a-kind.  If they get damaged, the option of making more prints is lost.  In digital form, a "digital negative" can be perfectly copied to many devices.
  • Processing.  You get access to tools like Photoshop which can allow for techniques not available in the darkroom.  It's also fast and inexpensive to experiment here.
  • Logistics.  You may not have room for a enlarger in your home - either in your opinion or your significant other's :)
  • Skillset.  Your Photoshop/Lightroom skills may be more developed vs. printing and some might find more "return on investment" in developing additional skills here.


Here I briefly mention different factors that you should consider when it comes to scanning.

Ease of Use

How turn-key is the operation?  Do you have to learn quite a bit and apply advanced techniques or is the operation easy?


Quality is a spectrum that starts at your immediate needs for a scan (e.g. post to social media) and extends up to inherit details captured by the film.  

One aspect of quality is resolution and there are a big range of possibilities.   Around 1 MP (1024x768 or so) is a good size for a social media post.  Somewhere around 24 MP (6000x4000) is what you can get from a 35mm sized frame with a "fine grain" film (like Fuji Acros 100) and "checking the boxes" through the processing pipeline (good technique, appropriate exposure, competent development, good scan).

Note that "resolution" is hard to pin down with film because it's higher in ideally-exposed areas with good texture.  The same is actually true of digital too, but we just take the manufacturer's word for what the resolution is, even if the actually pixels render a bit "mushy" in some places...

Larger film sizes offer even more potential detail, of course.

Quality has other factors as well, such as the dynamic range (DMAX range) that was captured and the accuracy of the color capture.

File format also influences quality.  If the file format is JPEG, then modifying the image without creating artifacts is more challenging than if the image is a 16-bit TIFF.

Those going for the ultimate archival quality will want high resolution scans (at least 3500 DPI), a large dynamic range, and accurate colors.  They will also want to store their negatives unprocessed (e.g. no inversion or manipulation) in a lossless 16-bit format, with TIFF being a safe choice.

A strategy I employ is to vary scanning and file format choices by image.  If the image is not technically impressive (such as having soft focus) but otherwise a keeper (e.g. family memory), I'll often store a lower-resolution copy (2 MP instead of 16, for example). I might also only store the final JPEG and skip the unprocessed negative TIFF.

Caution: The "spec" wars are out-of-control in the scanner space.  It's common practice to greatly inflate all the quality numbers.  For example, the popular Espon V700 scanner lists 6400 DPI as a resolution but achieves only 2500 DPI in testing (40% of their claim).  Sometime companies/models specifications match results much more closely, sometimes even less.

I found http://www.filmscanner.info/en/FilmscannerTestberichte.html to be a useful site for getting test data and reviews, although I've yet to personally discover the reason behind their enthusiasm for the Silverfast software.  Scanning software is is own topic, however.


If you have a large batch of photos to scan, throughput becomes a factor.  There are two ways to achieve this.

One is simply a scanning solution that can do more images / hour.

The other is a scanner that is slow, but automated (and can work through a roll of film while you are away).


How much do you have to spend to get that first scan?  Can you dual-purpose some of the equipment for other things (like general scanning, or photography)?

Also, if you are e-bay savy and are willing to buy used, you can often get out for the same cost you got in.


Do you only need to scan the popular 35mm size or do you have to handle medium format (120, 200 film) or even large format?

Automated Dust and Scratch Removal 

If your film is older and not well-stored, this can quickly escalate to the top of the priority chart.  We are basically taking about a combination of hardware and software that cleans up dust for you.  For example, some scanners also scan in infrared which allows for identification of a dust particles in color film.  If scanning with a DSLR, you can also naturally avoid dust by using a slightly wider aperture and a diffuse light source, pushing dust outside the depth-of-field. 


Let's look at typical solutions in terms of each factor.

Solution 1: Pay Someone


Under this strategy you pay someone else to do the work.  The main benefit is you get results without investing much personal time.  All other factors can in theory be done better if you DIY.

I personally have a local place that can do scans that I will sometimes use for quick things.  I've also had it done online.


Think around $0.20 - $0.50 per frame 35mm and a bit more for medium format.  You might find a local place that will do basic service for less.


The best part about paying someone is that you get pretty good results right away without having to spend upfront money on equipment or learn how to use it.  If you are just getting back into film or have limited scanning work to do, this can be a great way to start.


Critical quality is rarely as good as someone can accomplish at home.  The reason are are many fold:
  • Throughput: The person doing scan for you is likely motivated to get the job done quickly, thus picking"good enough" scan settings that get the job done faster.
  • Fully Baked images: You'll almost always get processed JPEG.  You'll also generally get white skies, even though the original film has detail there.  If you want something that is more editable, like TIFF, you need to shop carefully and it often costs significantly more.
The maximum resolution offered is also commonly much lower than you can achieve at home.  Often 6 megapixels or so, even for medium format!  Also this resolution is quite sufficient for most purposes, it's still quite a bit less than the film can deliver - it's a frame of mind thing.

The final con worth mentioning is that the costs build up over time and will overtake at-home solutions in a dozen rolls or so.

Here is an example of a paid scan verses at-home:

Solution 2: Cheap Dedicated Film Scanner


Anything under $150 or so new is a "cheap" dedicated film scanner.  Most scanner review sites don't even consider these devices as the quality is inferior to what is possible at ~ $150 and higher.

That said, if you are just looking to preserve some old film in digital form, maybe the quality is good enough and the ease-of-use factor makes it a good fit.


Under $150.  Some need a computer, others are fully stand-alone.


You don't need to spend a lot.  For non-critical work, like archiving old negatives, the quality is probably sufficient.


The quality is much lower than what is possible beyond the $150 price point.  Note that these devices are cutting every corner possible to offer such a low cost.

Solution 3: Mid-priced Dedicated Film Scanner


Around $170 seems to be the price point where companies can manufacture a device that really delivers on quality.  I'll defer to http://www.filmscanner.info/en/FilmscannerTestberichte.html for individual model reviews, but the general trade-off here is high quality scans but low throughput.  There is also a bit of a software maze to navigate, particularly if you want the very best color.  I personally recommend at least trying Vuescan, a paid program, but one that lets you freely produce "watermarked" images to personally see if the software is working out before purchasing.


Prices start around $170 and can go quite high for really high-end models.


Excellent quality is possible.  You generally have a full range of options, including TIFF and very high resolution scans.  This solution is the best I know of for critical color work.


The learning curve is a bit higher, especially if you want to extract maximum image quality.  If going for really good color, the learning curve is higher still.

High quality scans are slow, taking minutes per frame.  These scanners often advertise/accept higher resolution settings then they are capable of (applying post upscaling to fake it).  This requires extra experimentation time to learn the best scan settings.

Solution 4: Flat Bed Scanner (some with extra film scanning features)


Quality is a bit lower than dedicated scanner but perhaps good enough?  On the plus side, throughput is much improved and large scan sizes are not a problem.

Overall, the general trend seems to be about 1500 DPI for cheaper models (like the V600) up to 2500 DPI for top end ones (like the V700).  This corresponds to "high quality" print sizes of 5x7 vs 8x12 or so for a 35mm frame.  In contrast a good film scanner at 3500 DPI could give you a 11x17 print.


These start cheap, around $150 up to the $800 Epson V800.


These scanners can handle large-sized film.  Usually dedicated scanners stop at 35mm (unless you want to spend $1,300 or more for a medium format one).  Flat beds can often go to 4x5 and even 8x10 film sizes.

For smaller films, you can do more frames per pass with a flat bed.  The V700, for example, can do up to 24 35mm frames in a scan - convenient!

Another possible pro is that these double as nice document scanners.


All of the cons of film scanners, such as learning curve, more learning for color and slow scan speeds  apply here too.  Flat beds come with a few additional issues as well.  For starters, focus is generally fixed and, due to the large dimensions of the device, a bit more of an issue than with dedicated scanners.  When focus is slightly off, image quality suffers greatly and you might be stuck with creative measures on some scanner models (such as shims and third-party holders) to try and fix things..

Solution 5: Use a Digital Camera


This approach requires a higher degree of technical skill than the others.  Image quality can be excellent for black and white.  Getting good color requires additional skill and much time experimenting.  This is most ideal to try if you have most of the equipment already, or if you are looking for excuses to buy some, haha :)

I go through this approach step-by-step in my next post.


For black and white film, quality is actually very good, a match for anything else available. 

Throughput is better than any other method with only seconds needed per frame.

The most expensive parts of the setup, the camera and macro lens, can also be used for general digital photography. 

Companies are still pouring R&D into digital camera with tech that is currently 5-10 years more advanced than scanners have.  The gap will likely widen into the future.

There's no limit to the negative size you can capture.

There is quite a bit of flexibility in how you can set things up.

If you already own a digital camera and macro lens, you can try it for almost no cost at all.


It requires a much higher level of technical skill than the other methods.  This is especially true if doing color negatives with the expectation of good color results.

Digital cameras are specifically designed to capture positive images with most using a bayer filter.  In summary, it turns out that human vision is the most sensitive to the green part of the spectrum.  The bayer filter that digital camera use thus captures twice the green detail as the red and blue detail.

So what?  Well, when inverting an image, all the colors all change, in terms of the digital sensor:

  • The green signal becomes magenta
  • Red becomes cyan
  • Blue becomes yellow
Thus all green captured detail actually becomes magenta detail in the final inverted result.  Note that magenta is a mix of red and blue... the opposite of what the bayer array was optimized for!

All of this said, we still have options for regaining ground on the detail front (including the use of a blue capture filter and image stacking).  There is also the fact that digital cameras these days are so good that even when not at their best, they still produce some amazing output.

How to Choose

The above covered a lot of possibilities with many pros and cons.  If you've never done any scanning at all, it's likely not easy to weigh these, especially in terms of what image quality might be "good enough".

That said, none of the choices above have to be final, you can always try a few and build your own opinion.

I'd recommend first looking at how many photos you need to scan and if it's a one-shot deal or something that will continue.  Some basic thoughts:

  • Lots of old family photos?  Maybe their quality is not the best (e.g. not ideally stored, taken by non-photographer relatives).  If this sounds like you, then I'd lean toward paying someone or, if that gets expensive, just getting a cheap scanner for ~$100, then selling it afterwords.
  • Then again, if you have the equipment, you might approach the same problem with your digital camera.  Once you get a workflow going, each image will only take a few seconds to shoot.  If quality expectations are modest, you can use batch features of programs like Lightroom to get a full set of photos "decent looking" in seconds.  I explain how to do this in a future post.
  • If you currently shoot 35mm, then a dedicated film scanner is worth a look.  This is doubly-true if you shoot color film.
  • For medium format, options are a mix:
    • You can do digital camera captures: one image at the digital cameras resolution or many images stitched together.  Stiching requires more time and skill but is efficient in terms of getting 30-50 megapixel results.
    • I currently use a Pentax K3 ii with pixel shift.  This solution gives 24 megapixels, but avoids bayer filter artifacts, making the result superior to just about every single-shot digital camera currently available (but still not as good as stitching)
    • You can buy a dedicated film scanner for a good deal of money ($1300 and higher).  The main drawback here is that most can't do 4x5 or larger.  They are also slow.
    • You can buy a flatbed, like the V700.  This is a good choice for economical color work with a moderate resolution penalty.
  • Large format?  The options here are similar to medium format, but even more restricted.  By this point a flatbed starts to make a lot of sense, as the film carries excess detail for most use cases anyway.  Digital cameras can also be a nice option, due to their capture efficiency.
In my next article, I explore film scanning with a digital camera in detail.  The plan is to post this tomorrow so stay tuned!

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