In previous posts, we’ve seen numerical results of how various downsampling algorithms deal with Gaussian noise. Now it’s time to look at some pictures. The algorithms are: Photoshop’s bilinear interpolation Ps bicubic sharper Lightroom export with no sharpening Lr export with Low, Standard, and High sharpening for glossy paper A complicated filter based on Elliptical… [Read More]

This is the second in a series of posts showing images that have been downsampled using several different algorithms Photoshop’s bilinear interpolation Ps bicubic sharper Lightroom export with no sharpening Lr export with Low, Standard, and High sharpening for glossy paper A complicated filter based on Elliptical Weighted Averaging (EWA), performed at two gammas and… [Read More]

For the next few posts, I’ll be showing images that have been downsampled using several different algorithms Photoshop’s bilinear interpolation Ps bicubic sharper Lightroom export with no sharpening Lr export with Low, Standard, and High sharpening for glossy paper A complicated filter based on Elliptical Weighted Averaging (EWA), performed at two gammas and blended at… [Read More]

Yesterday I reported on the amount of noise, and the spectra, of noisy test images exported from Lightroom with sharpening turned off. Today we’ll see what happens when it’s set. Here’s the test protocol. The target image is a 4000×4000 sRGB, with each plane filled with a constant signal of half-scale, (0.5, 127.5, or 32767.5,… [Read More]

In the last two posts, I delved into how well Photoshop (Ps) does in minimizing photon noise when downsizing images using bilinear and bicubic sharper interpolation. Today I’m turning my attention to Lightroom (Lr). With Lr, you don’t get to choose your resampling algorithm or the gamma of the space in which Lr does the… [Read More]