The Trouble With Upsampling

Dear Debbie:

I submitted some photographs for possible use at a web stock agency and they sent me an email saying, "Please don't upsample your images.  This severely degrades the quality. This image contains undue artifacts when viewed at full size."

I shoot digitally and use Photoshop to resize my photographs. I have no idea what I'm doing wrong! 

Can you help?

Thanks,
A Sizable Problem

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Dear Sizable,

The first question I have for you is: How many megapixels does your camera shoot? Many stock agencies require a minimum image size, and if you want to sell a lot of stock, you may need to get a higher-megapixel camera.

Why? Because when you upsample, that is, when you go to Image > Image Size and type in a bigger Document Size while you’ve got Resample checked, you're inventing pixels that never existed before. And there are only so many pixels you can invent before your picture starts to look bad. Try blowing up a 4x6 image to 16x20, zoom in, and you'll see what I mean. The "undue artifacts" they're talking about are the leftovers from the interpolation process.

So to solve your problem, make sure you're shooting on the highest quality, highest resolution setting. And make sure your camera’s resolution is at least as big as the stock agency requires.

Hope that helps, and good luck,

Debbie

Comments

[Tammy]

Thank you for explaining this to me. I had asked several people and no one knew what it meant.

I use Photoshop 7. Can't afford the new one. Is there any tricks I can use to make the color stand out more in my photographs?

I'm shooting with a Canon Rebel Digital XT. It's 8 megapixels. I used to keep the size setting to Medium but have changed it to Large.

I shoot mainly nature, wild animals, and buildings. It seems the stock photo places don't really want those kind of photographs.

Any suggestions as to what would be more suitable?

Thanks,
A Sizable Problem

[Myron McPherson]

I use a Nikon D80 and I want to print multiple sizes from the same shot: 11 x 14, 8 x 10, 5 x 7, 4 x 6 & wallet. Do I need to crop the photo for each size and save the same file multiple ways to fit each print size so too much is not lost in auto cropping at online printers? And second I read that Corel Paint Shop Pro allows a user to change a blue shirt to red. Does this capability exist in CS2 or Photoshop Elements?

Thanks,
Myron.

[Nate]

Myron,

What you can do in CS2 to change the shirt color is to select the shirt using magic wand or your laso tools. And then with the shirt selected, from your image menu choose adjustments>hue/saturation. You then want to check the colorize checkbox on the left side of that dialog box. Then move the hugh, saturation, and lightness sliders to get whatever color you want. Hope this helps.

Nate

[Ole]

Hello Sizable,

I know what you are talking about, because I had the same problem - and rejection of my first submission. I am represented by a well know big agency and my first submission was, as yours, rejected due to up-sizing problems. I did my up-sizing in PS 7. I used at that time Canon D10, 6-point-something-MP, and had to produce minimum 48 Mb TIFF file and thought that my D10 was the problem. But the agency's support people kindly told me that the real problem was the PS interpolation upsizing method. I was recommended to use Genuie Fractals (www.oneonesoftware.com), which use another method, basically it evaluates much broader clusters of pixels and the computer time is longer.

My agency is not cheking all and every pics, but they are pretty sharp if something is wrong (a good way to learn the photographer to be more critical). I have done some 30 batch submissions now and no photo has ever been rejected due to up-sizing problems after using the Genuie Fractals software. So I can only recommend this (cheap) solution.

Hope this helps.

Ole

[Decomprose]

Sizable,

This may seem very simplistic, but in case you've missed it here is a very easy way to use Photoshop to bring out the colors on your shots: go to Image > Adjustments > Brightness/Contrast. Try bumping up Contrast by just 5 - 10% and check results. Save as a new file name so you can compare with the original.

Next, press control/U (in Windows) to open the Hue/Saturation window. Bump up Saturation by just 5-10%, and again save as a new file so you can compare with the original.

Be careful not to push either setting too high, as each will result in a degree of pixilization, and at highest values the Saturation control will affect hues drastically.

[Decomprose]

Myron,

In Photoshop Elements check out Print Preview. It will allow you to determine the size of the print job there at time of printing. It remembers the setting, so if you're not printing all of these at the same time you'll just need to specify each time what size you're printing that day. There is no need to save different files.

Cheers,
Decomprose

[Kristin]

I'm a little bit shocked. One of the first things I learned about working with images as a graphic designer is NOT to upsample. The only exception would be if you are working on a project where you are locked into to using a particular image that is too small and nothing else is available. In that case it is appropriate, but not preferable to print it at 150 dpi. If you are shooting stock photos and you don't have the equipment to take a large enough photo, then you need better equipment or you need not being taking stock photos. You aren't doing anyone any good by upsampling your images. Most stock photo vendors sell the image based on the size and the resolution so if you upsample, somebody is getting ripped off. Shoot large and only use photoshop to downsample. I don't want to buy a photo that someone has enlarged for me, and IF for some unlikely reason I want to make it bigger than it should be, I can do it myself.

[Nklauss]

Dear Debbie,

I have problems with undue artifacts also. I try to submit my picture to a stock photo agency. They reject some of my pictures using that reason. But I didnt do any upsample. Is there any other thing that can cause undue artifact?

Thanks
Nklauss

[Ibtrubl]

Dear Decomprose,

Maybe you need to extend your schooling. Some sites accept nothing less than 48MB which my olympus e-510 is incapable of doing without upsampling.

Cheers