IanfaeAiberdeen

I'm coming over to Affinity Photo from Photoshop and hit a problem which I had to resolve quickly - that meant reverting to Photoshop because I know how to do it. I regularly require reduced copies of photographs for websites, and with Photoshop I do this with Save For Web and Devices, using Bicubic Sharper as the resampling method. This option isn't available in Affinity Photo, which offers Nearest Neighbour, Bicubic, Bilinear, Lanczos 3 (separable) and Lanczos 3 (non-separable). I was in a hurry to do one in Affinity Photo, so accepted the default Nearest Neighbour, which produced a dreadful result, full of artefacts even saving as a JPEG 100% quality. I don't normally save in JPEG format (I prefer PNG) but it was a quick fix to replace a file uploaded from my iPad using a crappy (free) resize app which does only JPEG. It was quicker to open the photograph in Photoshop and do it there than to experiment with different settings or even consult the help system, so that job is done. Coming back to the problem, I find that here is zero information in the Affinity Photo help system (that I could find) explaining the different resampling methods and which is best for what kind of resizing. Wikipedia is not a great help, the article on Lanczos resampling being mathematical rather than practical. I have a degree in Physics and the maths isn't a problem, but it's no help in deciding on the most effective method for image reduction for the web. It appears that the Lanczos method introduces ringing artefacts which may give the illusion of sharper edges than bicubic, so one of these methods may be similar to Photoshop's 'bicubic sharper', which I find acceptable for reductions down to 300-400 pixels wide. Can someone explain in simple language which of the methods is most appropriate for my needs? I have a feeling that it is probably one of the Lanczos 3 methods or bicubic but it would be nice to know the ins and outs of each method.

Thanks, Alex and MEB. My point about the help system still applies but I've got it now. When you 'open' a PDF in Photoshop, it rasterises it before you can do anything else, according to settings which you can change in the dialogue box, so it is already in what Affinity calls a pixel layer and you can operate on it directly. In the case of digital images of newspaper pages, these contain only a single rasterised image or a paste up of a number of rasterised images and (if they have gone through OCR), one or more text layers. In Affinity Photo, a PDF opens as an object in its own right and you are in charge of rasterising it. I see the point because PDF files can contain a variety of different types of image and text and Affinity Photo can edit vector images directly, without rasterising, so you wouldn't want to rasterise the whole file if it contained vector images which you wanted to edit. The same might apply to text though the newspaper page I was working on didn't appear to have a text layer, or if it did, I couldn't see it in Affinity. Any chance of a tutorial on PDF editing? You're probably going to tell me to buy Affinity Designer .... Ian

Thanks, Alex. Using Shift-Command-C and then opening a new document with the clipboard allows me to produce a copy of the clipping isolated from the page. Then I can resize the canvas to leave a space at the top into which I can paste the sections of the page header. Same as Photoshop with the only difference being the use of the shift key. Subsidiary question: you refer to 'image layers' but this is not one of the types of layer listed in Affinity Photo Help (pixel, mask, adjustment, fill, snapshot, vector). What is an image layer and why isn't it listed as one of the types of layer - when you open a PDF and go to the layer panel, the layer is marked '(image)'? I found your second method very confusing because of the presence of the image layer but it doesn't matter because the first method fits what I need to do better anyway. Maybe this is a question for the developers to make the help system more helpful, so I hope they read this post. Ian

This may seem a stupid question but I am used to the idea of drawing a selection box round part of an image and hitting command-C or command to copy and then command-V to paste a section of the image somewhere else on the same image or on another one - that works in Photoshop. When I try to do this in Affinity Photo (working on a PDF image), after drawing a selection box, both Cut and Copy are greyed out in the Edit menu and using the keyboard shortcuts has no effect. I do this all the time in Photoshop with newspaper cuttings, using copy and paste to fit the page header with the name of the newspaper and publication date, which typically spans four or more columns, above the single column cutting. How can I copy part of an image in Affinity Photo?