Open Forum

Hello all,

Phone cameras and scanning apps have improved by leaps and bounds. Do they suffice for document and photo scanning? We've pretty successfully used integrated OCR to transcribe text through a telephone based app.

I guess I'm asking for pros and cons of built in scanning features with Google, Microsoft, Adobe and shareware apps. Convenience is great, especially for uploading to a shared drive while doing research. However, a flatbed scanner can give you more reliable perspective versus a human held device. Wondering where the tradeoff point is and if anyone has insight on what future tech can do for digitization projects.

Many thanks,


------------------------------
René Ballesteros
Community Engagement Officer
Museum of South Texas History
Edinburg, TX
------------------------------

There are very significant differences between photo "scanning" and true line scanning. Photo scanning is convenient and sufficient for practical conversion to digital form, but not appropriate for archival work. This assumes we are comparing handheld phones versus a reasonable quality line scanner, and that we are using both with care and practice. The major differences are resolution and distortion. A high quality phone captures a letter-size original at roughly 350ppi. Most line scanners can capture at over 1200ppi. And that is technical resolution, not "effective" resolution. My minimum recommendation for my video work is 600dpi and I don't consider that archival. Phone camera lenses, while extraordinary for their size are vastly inferior to a flatbed scanner, with a wide variety of distortions and resolution deficits across their effective capture area. In simple terms, the center of your photo is much higher quality than the outer edges, and the resulting image is geometrically distorted. With processing and at "photo" sizes, much of this is hidden, but it's there. A flatbed captures a consistent image across its entire surface without any distortion (assuming the object is flat). As an original gets smaller, the difference becomes more significant, not less. While the effective resolution of the camera increases, the distortion introduced by the lens increases as you get closer. And then there's the focus problem. It is very difficult to properly focus a hand-held phone camera with precision. Scanners do not have this problem.

As you push outside flat-bed scanning boundries, this equation can change. Clearly flatbed scanners are not ideal for non-flat objects or items of significant size. In some cases a high-quality photographic image would be preferred. ideally you would use a "large format" camera with high quality lensing, not a phone. I would never recommend a phone camera for anything archival. The idea that a phone can capture a "high quality" image is a subjective fiction perpetrated by phone manufacturers. Sure, "high-quality" in a social media context, but there are very good reasons professionals spend many thousands of dollars on their cameras and lenses.

Of course, if you are simply creating a digital record that is not intended for "archival" preservation, then convenience may trump quality. And that's when phones shine. I am not anti-phone. I use mine constantly for a wide variety of purposes, including professional work, but not because it is equivalent to the proper tools.

Cheers,
                 tod

------------------------------
Tod Hopkins
Technical Director
Hillmann & Carr Inc.
Washington DC
------------------------------

Hello! Three years have passed, but I'm hoping to dip briefly into your expertise, if you're still around (naturally, I'd be happy to hear from others, as well). My question regards flatbed scanning, and in particular flatbed scanning of pencil writing on paper. I've found that the flatbed scanner built into my sheet-feeding copier can do a very poor job with pencil writing; I'm guessing that the way graphite interacts with the scanning beam is somehow problematic. A mobile phone camera, on the other hand, does a much better job. I'm wondering whether this is a known problem? Of course, the answer might be that my sheet-feeding flatbed scanner is terrible, I should replace it, but I'm wondering if this is a known problem, possibly with effective workarounds?

------------------------------
John Clements PhD
Professor
San Luis Obispo CA
------------------------------

Original Message:
Sent: 10-07-2022 10:05 AM
From: Tod Hopkins
Subject: Phone Scanning Apps vs Flatbed Scanner

There are very significant differences between photo "scanning" and true line scanning. Photo scanning is convenient and sufficient for practical conversion to digital form, but not appropriate for archival work. This assumes we are comparing handheld phones versus a reasonable quality line scanner, and that we are using both with care and practice. The major differences are resolution and distortion. A high quality phone captures a letter-size original at roughly 350ppi. Most line scanners can capture at over 1200ppi. And that is technical resolution, not "effective" resolution. My minimum recommendation for my video work is 600dpi and I don't consider that archival. Phone camera lenses, while extraordinary for their size are vastly inferior to a flatbed scanner, with a wide variety of distortions and resolution deficits across their effective capture area. In simple terms, the center of your photo is much higher quality than the outer edges, and the resulting image is geometrically distorted. With processing and at "photo" sizes, much of this is hidden, but it's there. A flatbed captures a consistent image across its entire surface without any distortion (assuming the object is flat). As an original gets smaller, the difference becomes more significant, not less. While the effective resolution of the camera increases, the distortion introduced by the lens increases as you get closer. And then there's the focus problem. It is very difficult to properly focus a hand-held phone camera with precision. Scanners do not have this problem.

As you push outside flat-bed scanning boundries, this equation can change. Clearly flatbed scanners are not ideal for non-flat objects or items of significant size. In some cases a high-quality photographic image would be preferred. ideally you would use a "large format" camera with high quality lensing, not a phone. I would never recommend a phone camera for anything archival. The idea that a phone can capture a "high quality" image is a subjective fiction perpetrated by phone manufacturers. Sure, "high-quality" in a social media context, but there are very good reasons professionals spend many thousands of dollars on their cameras and lenses.

Of course, if you are simply creating a digital record that is not intended for "archival" preservation, then convenience may trump quality. And that's when phones shine. I am not anti-phone. I use mine constantly for a wide variety of purposes, including professional work, but not because it is equivalent to the proper tools.

Cheers,
                 tod

------------------------------
Tod Hopkins
Technical Director
Hillmann & Carr Inc.
Washington DC
------------------------------

John,

This is not a comment on phone scanning apps vs. a flatbed scanner but rather to let you and others in this forum know about VueScan Scanner Software that can help you keep the scanner you already have and, in many cases, improve its capabilities, especially for the all-in-one printer-scanners.

I first learned about it from a former colleague at the museum I worked at for many years, because Canon no longer supported my 2005 flatbed CanoScanner model. The VueScan platform had software that now makes it work, and it also worked on my (now-deceased) HP 3-in-1 beautifully, and current Epson. There are lots of adjustments you can make to the VueScan software so that light images, like pencil, can be better imaged.

There is a yearly subscription fee for it, but intermediate updates are free. This might be a solution to upgrading the scanner in your copier as well. More information at https://www.hamrick.com/.

------------------------------
Martha Katz-Hyman
Independent Curator
Newport News, VA
------------------------------

Original Message:
Sent: 09-11-2026 01:19 PM
From: John Clements
Subject: Phone Scanning Apps vs Flatbed Scanner

Hello! Three years have passed, but I'm hoping to dip briefly into your expertise, if you're still around (naturally, I'd be happy to hear from others, as well). My question regards flatbed scanning, and in particular flatbed scanning of pencil writing on paper. I've found that the flatbed scanner built into my sheet-feeding copier can do a very poor job with pencil writing; I'm guessing that the way graphite interacts with the scanning beam is somehow problematic. A mobile phone camera, on the other hand, does a much better job. I'm wondering whether this is a known problem? Of course, the answer might be that my sheet-feeding flatbed scanner is terrible, I should replace it, but I'm wondering if this is a known problem, possibly with effective workarounds?

------------------------------
John Clements PhD
Professor
San Luis Obispo CA
------------------------------


Original Message:
Sent: 10-07-2022 10:05 AM
From: Tod Hopkins
Subject: Phone Scanning Apps vs Flatbed Scanner

There are very significant differences between photo "scanning" and true line scanning. Photo scanning is convenient and sufficient for practical conversion to digital form, but not appropriate for archival work. This assumes we are comparing handheld phones versus a reasonable quality line scanner, and that we are using both with care and practice. The major differences are resolution and distortion. A high quality phone captures a letter-size original at roughly 350ppi. Most line scanners can capture at over 1200ppi. And that is technical resolution, not "effective" resolution. My minimum recommendation for my video work is 600dpi and I don't consider that archival. Phone camera lenses, while extraordinary for their size are vastly inferior to a flatbed scanner, with a wide variety of distortions and resolution deficits across their effective capture area. In simple terms, the center of your photo is much higher quality than the outer edges, and the resulting image is geometrically distorted. With processing and at "photo" sizes, much of this is hidden, but it's there. A flatbed captures a consistent image across its entire surface without any distortion (assuming the object is flat). As an original gets smaller, the difference becomes more significant, not less. While the effective resolution of the camera increases, the distortion introduced by the lens increases as you get closer. And then there's the focus problem. It is very difficult to properly focus a hand-held phone camera with precision. Scanners do not have this problem.

As you push outside flat-bed scanning boundries, this equation can change. Clearly flatbed scanners are not ideal for non-flat objects or items of significant size. In some cases a high-quality photographic image would be preferred. ideally you would use a "large format" camera with high quality lensing, not a phone. I would never recommend a phone camera for anything archival. The idea that a phone can capture a "high quality" image is a subjective fiction perpetrated by phone manufacturers. Sure, "high-quality" in a social media context, but there are very good reasons professionals spend many thousands of dollars on their cameras and lenses.

Of course, if you are simply creating a digital record that is not intended for "archival" preservation, then convenience may trump quality. And that's when phones shine. I am not anti-phone. I use mine constantly for a wide variety of purposes, including professional work, but not because it is equivalent to the proper tools.

Cheers,
                 tod

------------------------------
Tod Hopkins
Technical Director
Hillmann & Carr Inc.
Washington DC
------------------------------

Yes, pencil can be problematic. It's not particularly dark and it's also uneven and some graphites are reflective. Anything reflective is a problem for scanners. Some scanners may handle pencil better than others, but adjustments prior to scanning should help. Scan 8-bit grayscale, not color, or even "black and white" if your only concern is the pencil readability. Brightness and contrast adjustments prior to scanning can help a lot, especially for B&W scans. 

In general, flatbeds are better than sheet-fed, and there are definitely qualitative differences from one model to another. I suspect that your phone's superior results are because photographic processing is more like our visual systems. Cameras smooth out the world and fill in gaps like our eyes do. Scanners are very literal. 

In the world of image capture, accuracy and precision are not always your friends. 

------------------------------
Tod Hopkins
Museum Media Specialist
443-472-5978
tod@hoptod.com
------------------------------

Original Message:
Sent: 09-11-2026 01:19 PM
From: John Clements
Subject: Phone Scanning Apps vs Flatbed Scanner

Hello! Three years have passed, but I'm hoping to dip briefly into your expertise, if you're still around (naturally, I'd be happy to hear from others, as well). My question regards flatbed scanning, and in particular flatbed scanning of pencil writing on paper. I've found that the flatbed scanner built into my sheet-feeding copier can do a very poor job with pencil writing; I'm guessing that the way graphite interacts with the scanning beam is somehow problematic. A mobile phone camera, on the other hand, does a much better job. I'm wondering whether this is a known problem? Of course, the answer might be that my sheet-feeding flatbed scanner is terrible, I should replace it, but I'm wondering if this is a known problem, possibly with effective workarounds?

------------------------------
John Clements PhD
Professor
San Luis Obispo CA
------------------------------


Original Message:
Sent: 10-07-2022 10:05 AM
From: Tod Hopkins
Subject: Phone Scanning Apps vs Flatbed Scanner

There are very significant differences between photo "scanning" and true line scanning. Photo scanning is convenient and sufficient for practical conversion to digital form, but not appropriate for archival work. This assumes we are comparing handheld phones versus a reasonable quality line scanner, and that we are using both with care and practice. The major differences are resolution and distortion. A high quality phone captures a letter-size original at roughly 350ppi. Most line scanners can capture at over 1200ppi. And that is technical resolution, not "effective" resolution. My minimum recommendation for my video work is 600dpi and I don't consider that archival. Phone camera lenses, while extraordinary for their size are vastly inferior to a flatbed scanner, with a wide variety of distortions and resolution deficits across their effective capture area. In simple terms, the center of your photo is much higher quality than the outer edges, and the resulting image is geometrically distorted. With processing and at "photo" sizes, much of this is hidden, but it's there. A flatbed captures a consistent image across its entire surface without any distortion (assuming the object is flat). As an original gets smaller, the difference becomes more significant, not less. While the effective resolution of the camera increases, the distortion introduced by the lens increases as you get closer. And then there's the focus problem. It is very difficult to properly focus a hand-held phone camera with precision. Scanners do not have this problem.

As you push outside flat-bed scanning boundries, this equation can change. Clearly flatbed scanners are not ideal for non-flat objects or items of significant size. In some cases a high-quality photographic image would be preferred. ideally you would use a "large format" camera with high quality lensing, not a phone. I would never recommend a phone camera for anything archival. The idea that a phone can capture a "high quality" image is a subjective fiction perpetrated by phone manufacturers. Sure, "high-quality" in a social media context, but there are very good reasons professionals spend many thousands of dollars on their cameras and lenses.

Of course, if you are simply creating a digital record that is not intended for "archival" preservation, then convenience may trump quality. And that's when phones shine. I am not anti-phone. I use mine constantly for a wide variety of purposes, including professional work, but not because it is equivalent to the proper tools.

Cheers,
                 tod

------------------------------
Tod Hopkins
Technical Director
Hillmann & Carr Inc.
Washington DC
------------------------------

I agree with Tod's comment. Scanning apps are not replacement for flatbed scanning. They are inferior in every sense except for one which Tod does mention - Convenience.

It is because of convenience I use these apps and even recommend them. They are great when you do not intend to make archival images but simply need quick and convenient copies. They are also helpful in situations where you may not come across the documents or photos again. Working with small historical societies and people doing family genealogy it is often the case where they run into family members willing show/share photo albums but they may never see that family member again or the album. They have one chance to get a copy of a photo if they cannot rely on photos being scanned by the owner at a future date. Of course, a historical organization should still get a signed donation form (but that is another phone app). 🙃

A couple of good scanning apps are Google's own PhotoScan which is free, and Photomyne which is about $4 for the paided version. The paid version is still quite spammy and keeps trying to get you to sign up for things and services you don't need however it has one nice feature which is dealing with photos with curls in them and straightening them out automatically. ALL apps for scanning negatives and slides are not very useful and result is very poor quality images. The major issues, again are resolution and distortion. 35mm slides and negatives require capture at over 2400ppi. Phones don't come close. Additionally most phones on the market do not have macro lens capabilities yet.

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Joe Hoover | Digital Technology Outreach Specialist Minnesota Historical Society | Field Services
joe.hoover@mnhs.org | www.mnhs.org/lhs
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