The last thing you want pay for is a 4000 DPI slide scan, but the actual image is very low quality. The biggest misconception about resolution is thinking it also means quality. Find out why resolution has nothing to do with quality -- and how avoid paying for low-quality scans.

Misconception One: Higher Resolution Means Higher Quality

First, any scanner today will produce high resolution images. That is not the issue. The problem is when people see 4000 DPI, they think it is measure of quality. DPI has nothing to do with quality. DPI and resolution is just bits and bytes. All it is is just detail. And that detail can include dust, scratches, faded colour, etc. Of course 4000 DPI is better than 1000 DPI. But it does not improve colour, sharpness, exposure. Just know that DPI does not mean quality.

But make sure you at least have have a 3000 DPI slide or negative scan. And 300 DPI for photo scans. DPI is important when it comes to picking up detail. The more detail you have, the better chance of improving the quality. But do not be surprised when your 4000 DPI scans look worse than your originals if no effort was used to fix your scan.

To get scans to look as good as your originals or better, you need something more than DPI.

Misconception Two: Digital Ice Fixes Everything

So DPI can't help with quality. But what about Digital Ice? You've probably seen the Digital Ice logo splashed on all the scanners. In my ten years experience in photo editing, I know one thing: you cannot fix an image by pressing a button and letting the scanner do the rest.

Believe me, I wish it was the easy. But there's no short-cuts if you want something done right, the first time.

How Digital Ice works is it looks for a cluster of, say, white coloured pixels. Then it looks to see if that cluster is surrounded by an opposite colour, say black. If it is, it will fill the cluster of white pixels to the colour that is surrounding it -- in this case black.

I've actually had a scan where a person had no eyes. Digital Ice "thought" the white of the eye's were dust. So it filled the white area with dark pixels.

I have nothing against Digital Ice. I think its a great program. I don't rely on it because I can get better results using Photo Shop or GIMP. And often times Digital Ice is used as a short-cut to get as many scans done as possible. But what you save in convenience, you pay in quality.

Also, Digital Ice doesn't work for black and white images, or on photos. That's right, no Digital Ice on photos.

You cannot rely on scanners to do the editing. You need an actual person to fix the images with photo editing software like Photoshop.

Misconception Three: Your Slides, Negatives, Photos Were Kept In Good Condition -- So The Scans Will Look Great

I use high-end Nikon 9000 film scanners. But even with a negative that is only a few years old, it still comes out washed out. You see, the process of converting analog to digital is not exact. Even if you I have a slide that is one day old, my Nikon will not produce the same exact image (colour, exposure, etc).

Look at your photo, negative, or slide. You'll notice a glare, a shiny surface. Well, the scanner will also scan that. This is why even a new slide will come out "faded". The glossy surface blunts the colours when I convert it into digital.

To remove this glare, I use Photo Shop or GIMP to manually remove it. Digital Ice also has this option, but in my experience it's not consistent because every slide or negative is different.

This is where, again, I try to emphasize that there is no substitute for the human eye. Technology is amazing. Today's scanners are brilliant, even the $200 ones. But you cannot press a few buttons and expect a quality scan. You still need a human with some talent in photo editing.

Misconception Four: You Need The Highest Resolution Possible For HD Quality

Did you know that your 1080p, HDTV is only 2 mega pixels?! If you knew that, would you spend $900 on something that is only 2 mega pixels? Probably not. So marketers rather call it 1080p, and not 2 mega pixel. If you want geek out on the technical stuff, I'll show you how the math works below.

But that's the problem with resolution. There's so many numbers that are thrown around, it's all confusing. So, to help you understand resolution, here's a simple way of looking at it:

If your 4x6 photos are scanned at 300 DPI, they will be HD.

If your slides are scanned at 3000 DPI, they will be HD.

So, if you don't think you're not going to use your scans for commercial use, or make billboard size prints of your scans, these resolutions are good enough.

But, if you want to "future-proof" your scans, I'd recommend 900 DPI for photos, and 4000 DPI for slides / negatives. Remember how you had to replace your cassette tapes or VHS tapes with CDs or DVDs? Well, it's the same thing. At 4000 DPI, you know that your scans are at the highest resolution possible for now. Maybe in 20 years the technology will change. But at 4000 DPI you have an 18 mega pixel.

But don't forget! Resolution has nothing to do with quality. You might still have a 4000 DPI slide scan, but it doesn't mean it will look great. That scan needs to be properly fixed, personally edited using software designed to fix digital images.

Technical Stuff:

A 1080p, HDTV has a screen resolution of 1080 x 1920. It doesn't matter if you have a 32" or 52". It's just like your computer monitor. I have two monitors. One is 19" the other 21". But both have a screen resolution of 1388 x 780.

Anyway, when I scan a photo at 300 DPI, I get a resolution of 1200 x 1800. This number (1200 x 1800) fits snug on a 1080 x 1920 HDTV.

And how do you get mega pixels? Well, simply multiply the resolution: 1080 x 1920 = 2 million. Or in marketing terms, 2 mega pixels. But I guess 2 mega pixels didn't sound good for expensive TVs, so they used 1080p instead.

How To Avoid Paying For Low Quality Scans

Now that you know that DPI and resolution has nothing to do with image quality, you know what too look out for.

If the scanning company is advertising 4000 DPI scans, you know better that it doesn't guarantee your scans will turn out great.

If you read that the scanning company uses Digital Ice to improve quality, you know that you still may get some bad scans.

Remember, your slides, negatives, and photos aren't just images. These are your family's story. There's actual names and memories that go along with those images. If you care about preserving your family's story, then make sure the scanning company converts them into digital with time and care.

About The Author

Hi, my name is Konrad. I'm a digital designer, and I've been using Photo Shop since 2001. And I've been scanning since 2004.

If you have any questions about this stuff, please feel free to contact me using the form you see blow.

Thanks!

- Konrad Michniewicz