Thread: Optimize photos for poster printing

Your inkjet photo printer at home or in the office prints photos mostly in A4 format but you need<something a little more impressive. But an A3 printer is too expensive.

Numerous photo material suppliers, for instance, 'www.snapfish. com', specialize in large format prints. However, the rules that apply to large format poster prints are different than those for small format photo prints. Only correctly adjusted photos lead to the best possible results. You can, of course, simply upload the unedited photo and trust the supplier to optimize it automatically. That might work, but not all the time. It would be better to prepare the photo beforehand, in exactly the way you want it before uploading it to the website. The following steps are particularly important while editing a photo on your own.

Correcting Colors:

Almost all suppliers support the sRGB color scheme and therefore you should make use it even while editing your photos. In Photoshop, you can set the color scheme under 'Edit I Color settings'.



Setting the Resolution:

For poster printing in the 50 x 75 cm format, for instance, which is the largest size offered by many websites, the image file should have a minimum resolution of 300 ppi (pixels per Inch). If a poster printer outputs at resolutions like 1,440 dpi (dots per inch), it unfortunately means the print resolution will be stretched due to the raster. You can ascertain how many ppi a picture of a particular size contains with the 'Image

I Image size' function in Photoshop. Simply remove the check mark in front of 'Resample image' and type the desired size or resolution. Incidentally, photographic posters can make do with low resolutions, From a viewing distance of about a meter, you can hardly make out any loss in sharpness even at 200 ppi. For particularly large format posters, even 100 or 150 ppi is sufficient in some cases, from a distance of more than one meter. However, the edges of fonts or graphics appear considerably smoother at 300 ppi resolution.

Retouching Photo Errors: Scrutinize your picture carefully and touch up all minor details as per your requirement. In large format, these details will quickly become unsightly elements, which are strongly noticeable and can severely affect the overall impression of the picture. Pimples or color fringes count too. Moreover, check the histogram. Lifeless pictures without 'crispness', which means without powerful contrasts, make for dull posters.

Nice post andressa......