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I always look to change my wallscape in my office. We have a printer that can print large format but i never can find an image that can scale to 13 ft. wide proportionately without loosing clarity.

Looking at this answer" I need an image at least 100 ppi. With an image 13 ft wide, I would need an image which is a minimum of 15,600 px wide. (13 ft = 156 in; 156 in × 100 px/in = 15,600 px (minimum) required for 13 ft).

Are there any sites that offer such images as RAW or TIFF? I am stumped. Bigstock and Shutterstock don’t have the quality I am looking for.

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As far as I'm aware, no stock site is going to offer anything even close to those sizes.

Tiff is often possible but they generally max out at roughly 30" @ 300ppi. That means at best you'll get 90" @ 100ppi. Realize the call for such a large image is rare. There's probably little value in any stock site storing anything that large.

It may be possible to allow Photoshop to interpolate and enlarge further, kind of depends upon the image.

I think you are chasing unicorns. The best you are going to do is buy as big as you can find, then enlarge and repair as needed.

  • I've always wondered how they get photos big enough for billboards and the like. Then again, you see things like that at such a distance that maybe quality isn't that big of a concern. – Scribblemacher Mar 23 '18 at 11:28
  • To give an insider perspective: office murals are one of my specialities, and I've used images from several of the big stock libraries, and even produced murals for the offices of probably the biggest provider, so I had access to their whole library. In my experience, most stock images max out at ~30 megapixel mark, although I once worked with a panorama that was ~50MP. Everything I've worked on required interpolation in Photoshop. I've never encountered raw or tiff files: jpgs make sense when you consider the sheer volume of images that a stock library would be storing. – Dre Mar 23 '18 at 18:42
  • Many stock sites will provide tiff downloads as their "maximum". But your'e right, jpgs just make more sense. – Scott Mar 23 '18 at 18:45
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You can make needed high resolution images in better ways than interpolating in Photoshop. There's image enlargening software which very respectably guess sharp edges and narrow lines and do not make them wider. Subjectively the image stays sharp in for ex. 400% size. Of course enlargening software cannot generate any missing detail.

I have tried ON1 Resize and Smilla (freeware), both work well. Search for image enlargening or image resizing software for more to select from.

There are still other options left:

  1. Have a vector image ; originally drawn as vector or a vectorized(=traced) photo. They tolerate as much upscaling as wanted

  2. Stitch several photos seamlessly together. Photoshop has that function and there are some specialized photo stitching programs, too. Perspective differences, lens distortion and light differences are handled automatically, only minimal manual edits are needed.

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I am aware of how misleading that set of answers are. I will comment on this later.

Let me do the same math you did in more depth.

13 ft = 156 in. But "choosing" 100 PPI is not the correct path.

An image 15,600 px wide, according to the common proportion of 3:2 should be 10,400 px height or 162 Megapixels in total... There is no camera to my knowledge that has that kind of sensor.

A Phase One camera has a sensor of 100 Mpx and costs around 50,000 USD, so it is not affordable to many photographers. You will have a real limitation on finding stock photography even at that "smaller" pixel count. A photographer that uses this camera works for specific clients on specific markets.

That is not how things work, and that is, unfortunately, a reasonable conclusion by reading the answers on that thread. (I will post my answer later on that thread)

Things are done the other way.

  1. You choose a nice decent photo or let's say 24Mpx (Common nowadays and good enough resolution)

  2. This photo has 6,000 px wide, and then you imagine more or less how big your pixels, your detail will look at the printed size.

  3. 6,000/156 = 38.4 PPI. This is a pixel of less than a millimeter.

But in the end, if this is the photo you have, the photo you like it is ok to use it.

You can resample it and sharpen it a bit to reduce even more the pixel, so you now double the resolution to 76.9 PPI (1/3 mm)


Keep in mind that this is a perception problem. You notice more the lack of resolution on an image when you have sharp edges or small detail.

This sharpness is given by contrast between to sides of an edge. So on a blurry theme, you will notice less a pixel difference than a sharp theme.


In general, any 24Mpx (well taken) image will do fine in most cases.


About the RAW or tiff files... forget that.

A well generated JPG file is good enough to be used as a source material.


Now about the "misleading part", they are talking about viewing distances... You will probably assume that as you are sitting on a desk next to the wall, that point is your viewing distance. No.

A viewing distance is related to the human field of vision, assuming you are seeing the full picture, and more or less this viewing distance is the same as the biggest side of your images, in this case, 13 ft.

In this case, the implied viewing distance of a 13 ft wide image is 13 ft away.

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