create hi res/quality enlargements from a low res file

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Roo
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Post by Roo »

You could try Altamira's Genuine Fractals.....though there is a limit to what even that can do.

In my experience there isn't really much you can do to enlarge a low quality image.

HaraldHeim
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Post by HaraldHeim »

According to what I have read lately, the best tools for enlarging images are Genuine Fractals and S-Spline. On second place is Lazcos interpolation which is available, e.g. in the freeware Irfan View at www.irfanview.com.

bkmitch

hi res from low res

Post by bkmitch »

I've been using Alien Skin Image Doctor with pretty good results. It does a good job reducing the halos around re-sized images and cleaning up pixels. Again, if it's a low res images, you can only go so far.

artzend

Increasing dpi

Post by artzend »

I have taken a frame from a digital video (768 x 576 at 72 dpi) up to 1 metre x 1.25 metres at 300 dpi and had it printed.

I followed Ben Willmore's tip that you only increase the size of your image by 10% increments. This takes a while, but after running unsharp mask you should have a much better image than you would have thought possible.

You didn't state what size or dpi you were starting from and wanted to achieve, but the 10% at a time rule works ok because the software doesn't have to interpret a large section of pixels at a time. It copes better with smaller amounts and if you need to you can clean things up as you go.

Watch the colour discrepancy though, as I found that when I did this with an aqua colour, the greater the dpi, the stronger the blue came through and I had to use Hue and Saturation to fix the final image.

Tim Skyrme
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Threebirds

Miracle Enlarger

Post by Threebirds »

http://www.fredmiranda.com/SI/index.html

A Photoshop Action: $15 US. I've used it and it is amazing. It is an automation of the 10% increase in image size explained below. It is called Stair Interpolation. Think of the possibilities of using low-res low-cost images for print media. Or using a lower res camera and getting high res results. I can't praise this action enough.

-Steve

HaraldHeim
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Post by HaraldHeim »

The incremental 10% enlargement which is also used in the "Stair Interpolation" actions from Fred Miranda was rated as good as Lazcos interpolation in an article which tested several of these methods. But it is said to be less effective than S-Spline and Genuine Fractals.

Everyone can easily create an action in Photoshop that does these 10% enlargements. For example for a 200% enlargement, you need seven 10% enlargements and one 2.6% enlargement.

Overlord_Diabolus

Agrees with Harold...

Post by Overlord_Diabolus »

S-Spline is incredible! I'm always amazed at how crisp and sharp the images come out. ~Hail Thyself~ :evil:

harrie verstappen

reductio ad absurdem

Post by harrie verstappen »

Interpolation can work very well, up to a point. Now, go all the way down to a one-pixel image and try to enlarge from that. See what I mean? It's what Kodak used to call "false enlargement". The information just does not exist.

Echo Walking

Grow!!!

Post by Echo Walking »

I'm working with a 300dpi image that i need to enlarge into a life size cut out. What do you sugest? Almost 2 meter tall

HaraldHeim
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Post by HaraldHeim »

Currently I recommend Genuine Fractals and S-Spline for extreme image enlargement. Please check which one fits your purpose best.

Lightkeeper
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Post by Lightkeeper »

When using Genuine Fractals or S-spline, is there any need to enlarge in 10% increments, or is this automatic?

David

HaraldHeim
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Post by HaraldHeim »

Please notice that S-Spline was renamed to "PhotoZoom" recently.

You could make 10% increments with both tools, but I wouldn't recommend that. First of all, it means too much work. Secondly, 10% increments remove image details. Thirdly, you can simulate the 10% incremental effect with other means.

The 10% increments have the advantage of increasing local contrast in an image, but the disadvantage of reducing image details. So it is better to apply a local contrast adjustment after the enlargement. To do that you have to apply the Unsharp Mask filter with a high radius value and a small amount value.

Another trick for better quality is to sharpen the image before and after the enlargement.

apophatile
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Re: create hi res/quality enlargements from a low res file

Post by apophatile »

modsquad wrote: I vaguely recall recently a show on TV explaining (FX Channel??) how they can take now older films (like Apollo 13 for example) shot in conventional 35mm run it through a software (I don't know what?) and create a new CLEAR 70mm larger format (for larger screen theaters?) without the smoothing/fuzzy effect that you commonly get. Apparently this software has a superior pixel averaging capability that creates or interpolates "missing information" (if you will)??
The technology that you're talking about is called super-resolution. Here's a software that uses it (although it's not a plug-in): http://www.topazlabs.com/topazlabs/03pr ... az_moment/ . Some pretty nice examples on their site.

Gd luck

Lesam
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Post by Lesam »

I am no expert on this, I generally use Irfanview or Genuine Fractals to resize, however an Overview of Seam Carving see
http://www.seamcarving.com/ caught my eye and I found Resizor, a free program at http://www.peterw.000webhost.com/resizor/
which among other techniques uses Seam Carving.
I have not had a chance to really try out the program, so cannot at this time comment with any authority.
The only stupid question is the one you didn't ask

Lesam
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Post by Lesam »

Apologies, Resizor only uses Seam Carving to reduce image size
The only stupid question is the one you didn't ask

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