Is File Format Actually Important?
Last week in part 1, I wrote about a print being the total sum of all the parts in the workflow and how each part plays a role. We also touched on the importance of proper exposure for a good starting place. As promised, this week I expand the parts to cover gear and the common question of file formats.
If your lenses are of poor quality, don’t expect your images to be ready for fine art printing. Aberrations distortions and flares, like exposure, can only be somewhat compensated for, but not completely repaired in Photoshop. ANY distortion corrections in Photoshop means that your pixel data will be re-sampled. And re-sampled means it will be softened. Flairs, result in lowered contrast that equates to lessened detail, and repairing apo-chromatic errors requires re-sampling one or more channels. It’s preferred to handle this during raw conversion but it still requires a re-averaging or re-sampling of pixel data.
For a fine art image, Unless jpeg artifacts are part of your style, (see my blog post on tiff versus jpg issues here) I recommend that the image be captured in an uncompressed raw format. Some camera manufacturers force users into either jpeg or compressed raw formats. For the wedding and portrait guys. This is usually fine. Their critical gamut for color lies mostly in the skin tone ranges of their subjects and the rest of the world is secondary. In a fine art print, the rest of the world is the artists domain and critical for color. JPEG compression throws color information away first at the higher quality levels, then moves on to also discarding density detail as the compression level increases. I have yet to see a digital camera that will hold the same level of color fidelity in the compressed file, that can be had in an uncompressed raw file. With the rapid pace of camera development, I imagine this issue will be corrected in a few years, if not sooner. I suppose we’ll just have to wait.
Do as much of your color correction, saturation work, density tuning and sharpening during the raw conversion process as you can. Any resampling of color post-conversion can lead to lesser results when levels of density in each color channel are expanded, leaving gaps that cause rapid transitions in color, or compressed, causing a loss in color fidelity. Am I nit-picking here? Could be. But remember, the topic is getting the best possible print. Nit-picking get’s you to that end. Shortcuts might get you an acceptable print, just not the best print possible.
The software used to convert your raw files can also go a long way to make or break your image. For several years, I have been using Bibble Pro to convert my raw files. Side by side tests with current adobe products show that Bibble preserves more color fidelity and introduces virtually zero artifacts into my files. Adobe products appear to be using an interpolation scheme that sometimes creates zipper lines on hard edges and at other times, completely softens color detail in some of the channels. When my distant Autumn aspen trees look like cotton candy in the red channel, missing all semblance of leaf detail, something is horribly wrong with the adobe raw converter. Prior to final file work, I always convert my raw files to a tiff in a decently sized working space such as ProRGB or Adobe 1998. Especially for anything I will be printing on either photographically on the Lightjet or on Giclee watercolor or canvas.
Let me know your thoughts. I would love to hear your ideas.
Next from me: Sweetening the print through fine-tuning.