Rescaling vs. Re-Sampling Photos and Why it Matters

The subject of resizing your photographs to make a high quality print or to share it online continues to be question that comes up in forums. Part of the confusion stems from the terminology itself. In this post/post, I will discuss the subject from the standpoint of scanning a negative or slide. First, Are a couple of comments about the terminology.

Resolution – Dots Per Inch

Resolution is generally referred to as either dots per inch (dpi) or pixels per inch (ppi). What can lead to confusion is that dpi is used to describe the resolution of a scanner. For example, a scanner that is capable of scanning 35 mm negatives may have a optical resolution of 3200 dpi or greater. The word optical here means there are no mathematics being used to artificially increase the resolution. For the best quality, you should scan at or below the optical resolution of the scanner.

Resolution – Pixels Per Inch

Referring to a scanned image, once you open the image in say, Photoshop Elements or Photoshop, the terminology changes. Now the same resolution is measured in and referred to pixels per inch (ppi). The resolution is the same as you scanned, the term just changes. For example, if a negative is scanned at 3200 dpi and then opened in PSE 15 using the Image > Resize > Image Size command, the dialog below is opened. The resolution of 3200 ppi is shown.

3200 ppi ex

Print Resolution – Dots per Inch

When describing the resolution of an inkjet printer, dots per inch or dpi is again used. However, at this point in the process, the term takes on a whole new and more literal meaning. Now it is used to describe how many drops of ink are placed on the paper per inch. It is one of the prime, but not only parameter that is used to describe how well the printer can reproduce the image. And, this number has nothing to do with the resolution of the image file (in pixels per inch) that was sent to the printer.

This tutorial is an exercise that will not only give you a better understanding of rescaling an image versus re-sampling it, but will also demonstrate the loss of quality that is a bi-product of up-sampling an image, or adding to the number of pixels that were not in the image when it was scanned.

To view or download the tutorial, click on the image below. I suggest you actually follow along with the tutorial using one of your own images.

Resampling Comparison

In this post and tutorial I have focused on resolution as it impacts the printing of your digital photographs. In a future post, I will cover the topic of how to properly size your photos for sharing them online.

If you found this tutorial to be helpful and would like to see other tutorials in the future, please give it a suitable star-rating and  share it with your friends.

Until next time..


Printer Blues–Chapter 2

In my earlier post, I explained the clogging problems I was having with my Epson R1800. You can see that post by CLICKING HERE.

In that post, I said I had taken my printer to the repair station. They had called me back saying so far they were unable to unclog all of the nozzles. They were going to give it another shot on the weekend, and call me back. They did call on Tuesday to say they were unable to totally unclog all of the nozzles, although they were successful with some. I picked up my printer and talked briefly with the technician. According to him, my problem was probably caused by a combination of not using the printer enough and using non-Epson cartridges. He also said their company only uses Epson cartridges, unless the customer insists on non-Epson brands.

So now I have my $500 printer at home needing a $350 print head. As I said in my last post, I have ordered a cleaning kit for about $20. It should arrive in a week or so. When I get it, I’ll try cleaning the nozzles one more time myself. If that does not work, my printer is off to the Goodwill.

By the way, I was not charged anything by the repair shop, since they could not fix the printer. Their standard service charge is $85. I think what they did was more than fair, since it sounds like they tried repeatedly to unclog my printer.

I see a Chapter 3 of this series to let you know how I make out using the the cleaning kit myself. Stay tuned.

Have any of you tried cleaning your inkjet printers with one of the many kits available? If so, leave a comment and let us know how you made out, OK?

If you find this post of value, please rate it above. Thanks.

Epson Printer Blues

Look’s like I screwed up my Epson R1800 printer. This is my prime printer for photos. I have an Epson 1280 I use for everyday printing. I have always used Epson inks on my R1800, which uses pigment as opposed to dye-based inks. Buying Epson brand ink, even online is about $110.

Originally, I also used only Epson inks in my 1280. About the time I bought my R1800 and stopped using my 1280 for photos, I began to buy non-Epson ink for my 1280. Doing this cost me about 30% of buying Epson ink. I use this printer all of the time and have had only minor ink clogging problems over the years.

So about about a year or so ago, I began to buy non-Epson inks for my R1800 at roughly 60% savings relative to Epson-brand ink. I began to have significantly more ink clogging problems than before. I was slow to react to the problem, because I was printing less photos than I had been. At times, I would not use my R1800 for two or three weeks.

So about three months ago, I took my R1800 to a repair shop and had it cleaned etc. I had never had it serviced since I bought it, and I figured it was time. I was not very impressed  with the store, and frankly I do not think they did that good of a job. By the way, I basically cannot find a list of Epson authorized service centers by going to their website. If anyone knows of one in the Los Angeles area or the link to Epson’s list of service centers, please leave a comment.

So over the past couple of months, my clogging problems have increased tremendously. Also, I have had other quality related issues with the non-Epson ink cartridges I have been buying. Recently, I have spent (wasted) a lot of money fighting this problem. By the way, the non-Epson ink cartridges I am buying for my 1280 continue to perform about the same as the Epson ink I initially used.

It all reached a head late last week. I could no longer get my R1800 to pass the Nozzle Check Test, no matter how many times I ran the clean cycle and its more sophisticated auto cleaning routine. I was using up lots of ink trying to clean the nozzles. Blue the ink was almost not present, in the print pattern, even though I put in two different blue cartridges, hence the title of my post. Through Google, I found an Epson authorized service center nearby and took my printer in last Thursday. They called me back Friday. So far they have been unable to unclog my printer using special cleaners and syringes.  They told me I need a new $350 print head. I only paid $500 for the printer. They are going to try some more, and call me back on Monday. I fully expect the result will be the same, so I’ll go and pick up my basically worthless printer.

Fortunately, my daughter gave me her R1800. She had a few ink clog problems and got frustrated, so she gave it to me a few months ago. She basically only prints 4×6 and now and now uses an online printing service. A couple of print nozzle cleaning cycles and her printer is working perfectly. By the way, she has only used Epson inks.

So here is my plan. Assuming the repair shop cannot get mine to function properly, I will bring it home and try to clean the nozzles myself. What harm can I do? Nozzle cleaning kits are a hot item all over the internet. I’ve already ordered one for $20 or so. It should arrive in a couple of weeks.

I’ll let you know how this all turns out in a future post. To be honest, I’m not sure I am going back to Epson inks or not. I want to talk more with the technicians who worked on my printer.

So far, I have learned one thing, however. You are better off using your printer than letting it sit for extended periods regardless of the brand of ink you use, especially if it uses pigment inks instead of the more common (but less permanent) dye-based inks.

Stay tuned.

Please leave a comment and tell us about your photo printing experiences.