Best way to resize an image up from............

[admirable]

Best way to resize an image up from 4896px X 3264px to 43200px to 28800px

 

[dean messenger]

perfect resize can work well, but your talking a huge increase in scale which i think would cause tremendous issues in image quality.
i assume this is for printing purposes?

 

[admirable]

Yep, it for a vinyl to go on the side of a lorry

 

[admirable]

Length is from 68 inches to 144 inches

 

[StewartR]

How many pixels per inch does the printer require? If you're printing on vinyl I'd expect about 75-100 ppi, and certainly not 300 ppi.

If your final image is 144 x 96 inches (12 x 8 feet), then at 100 ppi your final image needs to be 14400 x 9600 pixels. At 75 ppi it needs to be 10800 x 7200 pixels. That's a lot smaller than the numbers you mentioned.

 

[admirable]

How many pixels per inch does the printer require? If you're printing on vinyl I'd expect about 75-100 ppi, and certainly not 300 ppi.

If your final image is 144 x 96 inches (12 x 8 feet), then at 100 ppi your final image needs to be 14400 x 9600 pixels. At 75 ppi it needs to be 10800 x 7200 pixels. That's a lot smaller than the numbers you mentioned.

Yes I agree but I can worry about the ppi later, I want to find out the best way to do this without losing too much in quality

 

[StewartR]

Yes I agree but I can worry about the ppi later, I want to find out the best way to do this without losing too much in quality

Sure, but the point I wanted to make was that the best way to upscale it might depend on how big you're trying to make it.

Your original idea was that you wanted to make it about 9 times bigger in each dimension. I'm suggesting you only need 2-3 times bigger. That should be easier. For example you *might* trust Photoshop to handle a 2x resizing but not a 9x resizing.

First work out what you need to do, then work out how to do it.

 

[admirable]

See post 4, that's what I need to do.......................get it from 68 inches to 144 inches on the longest side

 

[StewartR]

So we should ignore post 1 where you say you need to go from 4896px to 43200px?

 

[admirable]

So we should ignore post 1 where you say you need to go from 4896px to 43200px?

For the meantime yes, do you have any ideas how to best achieve this?

 

[Alastair]

For the meantime yes, do you have any ideas how to best achieve this?

See post #5

First start by identifying what you need, what resolution does the printer need?

You can't ignore the resolution question if you want to get this right.

 

[admirable]

I have three options,
1/ 300ppi printed on paper and then laminated = most expensive
2/ 100ppi printed on vinyl = best option I think
3/ 120ppi printed direct onto fomex board = most work

I can see this is going to be more hassle than it's worth

 

[droj]

Whichever choice (and I suspect that 300ppi is a step too far), I'd save out a crop of the image to experiment with (to save processing time), and upscale it in stages rather than in one fell swoop, inspecting results as I went, with Photoshop. It could even be that a better result would be to upscale somewhat beyond the finished size then downscale back to it?

 

[admirable]

Whichever choice (and I suspect that 300ppi is a step too far), I'd save out a crop of the image to experiment with (to save processing time), and upscale it in stages rather than in one fell swoop, inspecting results as I went, with Photoshop. It could even be that a better result would be to upscale somewhat beyond the finished size then downscale back to it?

Thanks, Yep I tried that last night using a 10% upscale each time. Unless I find a better means or software that's how I'll do it.

It was a holiday here yesterday so the printer will get back to me at some point today