Hi everyone,
I do some fashion photography for a group on campus, and they want an image blown up to 15 ft. tall by roughly 9 ft. wide. The original was shot in RAW on a Canon 50D (15 megapixels). What is the best work-flow to have the best possible quality with this large of an image? Thanks!

Michael - I recently had a picture blown up to poster size, this is not the same as 15 feet but the process is the same. Contact the vendor who is doing the work, and inquire the format and the minimum standards they require. If there is any editing work, make sure all the minute flaws are remedied, then the vendor does the rest. If your photo already exceeds the minimum requirements, you need do nothing more, other than pray the vendor does not screw up your good work. There have been billboards created with a lot less than 15mp.

If you decide to do it on your own, you might want to look into a program I believe is called "Genuine Fractals". I forget if it's a stand-alone, or a plug-in for Photoshop. If you decide to get it done by someone else, try looking into adorama.com, and mpix.com

good luck :o)

Okay great, I am downloading the demo version of Genuine Fractals. I still have CS3 so I'm not sure if it'll work. If I want to just perform this action in CS3 what is the best workflow? Thanks.

Michael - Genuine Fractals, can be a stand alone program and it will become a plugin or filter (both same thing) for Photoshop. One of the nice features for this pricey program is that it allows you to increase the size of your picture. It does a fairly good job of increasing the size and marginally maintains quality. I guess at this point I need to ask if you are creating the large 15 foot photo or are you having a vendor do it? Most vendors have the necessary programs to increase the size of your picture and maintain image quality. Then they also have the hardware to create the image. I am puzzled by your request for the workflow? Did you already take the picture? Are you happy with the quality of the image? Does the image need post-shoot editing? A little more info please. Thanks

if you are doing a large poster then you do not need to be in high resolution as they are never viewed up close and so optical resolution takes over from physical resolution - for instance - bill board poster images are 72 dpi or less.

The science behind it being that from a certain size/distance the eye only perceives a certain level of detail so any more resolution is superfluous - hence most reading material being printed at 300 dpi, which is the optimal resolution for close inspection.

Sooooo – for your big poster, take your image and process it as you would normally if it’s a raw file then in Photoshop, set the resolution to 72 dpi by disabling the resample image option – this increases the physical dimensions of the image but leaves the optical appearance the same.

You may find that after that, you still need to enlarge some more which is where the third party plugins mentioned come into play – in any event – do NOT leave the image at 300 dpi as your resulting file will be too large in memory size to be useable/editable/printable.

Hope that helps.

p.s. in 'ye olde repro' terms this is referred to as dim scaling.

p.p.s. if you were planning on doing post work/effects - convert your RAW to 16 BIT - do the effects and post on it in photoshop then do the dim scale as the last stage and conversion back to 8 BIT for print.

Sounds like Philc knows his stuff. I'd go with him. Thanks for the lesson. The dots per square inch makes a whole lot of sense. Along with the RAW conversion.