Automatic Cropping With Pic Scanner – Get it Right

Automatic cropping is the key effort-saving feature of Pic Scanner app, but what if your photos are split in random places or look skewed? You could re-scan, but the tips below will help you get accurate results every time (Hint: Many users get #4 wrong):

(Note: These tip apply to both apps – Pic Scanner and Pic Scanner Gold).

1) Use plain background:

Lay photos on a plain white or single color surface. Multi-color background won’t work well. In the pictures below, #1 may lead to wrong cropping, while #2 and #3 are fine:

2) Mind the gap between photos:

When scanning multiple photos together, keep a 1/2-inch i.e. 1-2 cm gap between them. If pictures are too close together, the app won’t recognize them as separate images. In the screen shots below, #1 is wrong, #2 is fine:

If your photos are in albums, you can scan an entire page at a time – again, provided that there is a gap between the photos. See examples below – what’s OK and what isn’t:

abum

3) Ensure contrast between photos and background:

It helps to have some color difference between the photos’ edges and the background. So, for example, to scan a snow scene, place it on black or another solid color background (Not white).

scan-contrast

4) Keep photos fully visible:

This is the most important tip: In your scan, a bit of the background surface must be visible all round the photos. If any photos reaches the edge of the viewfinder frame or extends beyond it, cropping will be wrong.

Below, #1 is wrong (Left and bottom edges touching the viewfinder’s edge), #2 is good. Note that #3 is also correct, but here the camera is held too far away  from the photo, and will result in lower resolution scan.

scan photos app

How to scan and how not to scan photos

5) Avoid perspective distortion:

If scans are skewed or distorted, you need to hold the camera centered above the photos and level with them. Pic Scanner has built-in automatic perspective correction, but try to avoid holding the camera off-center or at an angle to the photos. In the illustration below, the photo on the left doesn’t look rectangular because the camera is tilted. Usually our apps will correct for this, but in some cases you may end up with distorted or wrongly cropped results.

skewed-scan

6) Long and narrow photos

Photos with (Length > More than 2.5 times width) may not be cropped correctly. These can be cropped manually from Originals screen.

7) Special situations:

There is one more situation where automatic cropping may go wrong. See the photo below:

image

Pic Scanner intelligently guesses where a photo’s edges lie. But if a photo contains prominent straight lines, these can be mistaken for edges. Below, we have highlighted these edges in yellow:

unnamed

If cropping is wrong (or a photo is missed out), you can crop manually from the Originals screen (Tap Original thumbnail > Trim > Adjust size and position of the cropping rectangle > Crop. The photo will be saved on Cropped screen.

Some users ask if they can turn off automatic cropping or share originals. Automatic cropping is a real effort-saver, and by following the above guidelines, you won’t need to crop manually. However, you can also transfer Originals to Cropped screen, and then share them. This is how:

On Originals screen, tap Select. Tap one or more photos to select them. They will get check marked. Tap Move, then Move to Cropped.

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A bit more on scanning album pages: If the photos in your albums are too close together (but not touching each other), you can still auto-crop them. Even 6-8 mm gap is enough for the app to recognize them as separate photos. Just scan one or two photos at a time instead of the entire page, by holding the camera closer to the page (See below: Scanning 2 photos at a time). With a bit of trial and error, auto-cropping will work.

album1   album2 

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If your photos were cropped wrong and you can’t figure out why, just send us the cropped and original photos. We will analyze and guide you on what to do.

Blog of Pic Scanner, the photo scanner app for iPhone and iPad. Tips on how to digitize old family photos

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