How can I blow a picture up poster size without losing the quality of resolution

Question: How can I blow a picture up poster size without losing the quality of resolution!?

What do I need to do to accomplish this
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Best Answer - Chosen by Asker:

The quality and resolution of the original image will affect how well the image works as a poster!. For full photographic resolution, you need 300 pixels per inch (ppi)!. For an image 3000 x 2000 pixels (~6MP), that gives you 10 x 6!.7 inches!. You can stretch this to 200ppi (15x10") with no noticeable loss of resolution!. However, since posters are meant to be seen from a few feet away, you can sacrifice some ultimate resolution without looking too bad!. Images printed at 75ppi will not look photo-sharp viewed close up, but look fine hanging on the wall, if the original image is good quality!. That would give you a 40 x 27" poster!. Be aware that if the original image isn't sharp and clear, it can look pretty shabby blown up, as any noise or blur will become very obvious!.

The best way to enlarge digital pictures for poster printing is to rescale them to 300ppi at the intended print size!. Photoshop, Gimp, Irfanview, and other image editors can do this!. Specify that you want to resample, and choose smoothing if it's offered!. The place that prints the posters may be able to do this for you, as well!.

Just to see what it would look like, I recently printed a portion of a photo at 25 pixels per inch, re-sampled and smoothed!. It looked more like a water color than a photograph, and there was a little stair-stepping on some straight lines, but for a photo where color and composition were more important than detail, it just might work!.Www@QuestionHome@Com

The file size determines the size of print you can get, the rule of thumb is 1Mb per Inch on the longest size, so if you want a 30" X 18" poster you will need a 30Mb file for a halfway decent print!.

If your file is not this large Gimp or Photoshop and a host of others can 'pad' out the file with data derived from the surrounding pixels (its called 'interpolation')!. There is a limit, quickly reached, to this before quality just disappears, normally reckoned to be about 3X so for your 30" X 18" print the absolutely smallest file size is 10Mb!. Below this there is no point as there would be more 'invented' data than real data!.

You can find the file size by right clicking on the pictures icon and going to Properties at the bottom of the sub menu!.

ChrisWww@QuestionHome@Com

I will echo the sentiment that what you need is a high enough resolution image to begin with!. Enlarging any image will only result in making larger pixels!. If the pixels are EXTREMELY small to start with (high resolution) then the larger pixel results may not be too noticeable!.

Another issue is the typical viewing distance of the poster!. If the poster is meant to be viewed from, say, ten feet or greater distance, then the larger pixels will be lost in the distance and the poster will look just as good as one done in a higher resolution!. Next time you get a chance, take a good look at the advertising posters along the sides of a bus!. If you stand just a few feet away, you will notice HUGE printing dots making up the graphics!. But, from across the street, the images look smooth and photographic!.Www@QuestionHome@Com

You need a hi-res image to begin with!.

For poster size I do not recommend anything less that 6x7cm, If you really want poster size with no apparent loss of resolution then I recommend 4x5"!.

If you have not taken the picture yet then you might want to rent a EOS-1 Mark III ds!. That small 35mm sensor is capable of astounding results!. It should do poster size no problem if you have great glass!.

If you have an existing picture then there is not much you can do!.

jWww@QuestionHome@Com

in order to do that, the picture had to be taken in high resolution!. if it's a picture you took yourself, it depends on the pixels in your camera (the more the better)!. If it's a picture online, it's hard to tell if you'll be able to do that!. The higher the pixels, the larger the file too!. Hope that helped!Www@QuestionHome@Com

How many mps is the picture to start with!? I have gotten 24x30 enlargements from a 6 mp dslr that was beautiful and with no loss of quality!. I know the mp police will say this can't be done, but it can if it is a well taken picture to start with!. Trash in trash out!. That comes into play when you start making large enlargements!. also the printer, make sure you use a quality printing service!. www!.mpix!.com is who I use for all my really large printing needs!.Www@QuestionHome@Com

You can try scanning the photo and using paintbrush effects to increase resolution and make it look more natural when it's larger!. If it's already high resolution it shouldn't loose to much qualityWww@QuestionHome@Com