LenC
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Posts posted by LenC
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Further to my issue a couple of posts above, about not being able to launch the beta, it was possible to see the beta splash screen, and a dot under the icon in the Dock indicated that the program was active. After quitting the beta and launching AP 1.6.7, its (the latter's) splash screen was very persistent and did not go to gray background; in fact it persisted on top of an image of my own I loaded but finally went away when I clicked on it.
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I believe the Mac. It says 1.6.7.
BTW, can the bought and the beta run simutaneously?
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I get the same error window as chilacho, p. 1 of this thread, but my Affinity Photo.app is in my Applications folder right next to the beta, which will not launch.
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I am a beginner in LAB attempting to apply the writings of Dan Margulis, who uses only Photoshop, to Affinity Photo. The LAB underlying functionality is mostly OK, but I have found that the AP user interface could be improved in several places. More experienced users, please comment.
1) In the Curves adjustment layer with LAB selected, the A channel curve is colored green and the B curve magenta. The appropriate colors are green left and magenta right for A; blue left and yellow right for B (with light or high luminosity on the right).2) Creating a check box on the A and B curve windows for Intersect Midpoint would make it easier to construct color-intensifying curves. This is probably the most important basic move in LAB, and even Photoshop does not have this feature.
3) The Input Minimum and Maximum default to 0 and 1. Though I have not found a use for these, shouldn’t they be -1 to 1 or -100 to 100 or -127 to 127?
4) The Curves/LAB window’s second drop-down menu offers Master, L, A, B, and alpha. Is there a known use for ‘Master’ as in RGB? Nothing I have read about LAB indicates that there is. For that matter, is there any use for Master in CMYK? And how about ‘All’ as an alternative to Master in RGB? Furthermore, the histogram curves displayed for the LAB components here are not positioned the same as when one transforms the document to LAB and displays its histograms. May relate to previous point (3).
5) Photoshop can display the graphs of the various color space curves with the light (high-luminosity) side on the right or left (one-click toggle). This option would be useful to people learning from Margulis’s books, which show dark on the right.
6) Other Affinity users have called for improvements in the Curves window in general, not just for LAB: more precision and ways of placing nodes, a larger or scalable window, saving curves. Because of the sensitivity of the A and B curves to small movements, a fine control on node dragging would be handy, e.g., option-drag would reduce the motion by 1/5 or 1/10. Perhaps it already exists.
7) A LAB curves user on this forum called for a keyboard shortcut to move among the channels. Why not? He needs efficiency in a much-used workflow application. In the same vein, having selected the color space, instead of a second drop-down, radio buttons for the three or four channels would slightly simplify choosing one.
8) In the Channel Mixer adjustment layer, the LAB window A and B sliders need appropriate coloring like the RGB and CMYK. Just for consistency.
9) The Levels adjustment layer makes sense in RGB, but I am not so sure about LAB and CMYK. Does this lead to a useful correction? (Please help me, advanced users.) If you push the existing RGB colors to the AB limits of +/-127 won’t you just create out-of-gamut colors that will have to be distorted back in RGB space? And is gamma defined for this color space? Also, in the LAB window, shouldn’t the correct labels for the sliders be, for the A channel, green and magenta, and for the B, blue and yellow. Similar questions for CMYK.
10) The Apply Image filter and Channel Mixer adjustment layer seem as if they should have similar functionality, but their capabilities and interfaces are rather different. My understanding of Apply Image in Photoshop from Margulis is to blend or replace channels one at a time, sometimes across color spaces, but to do that in AP one has to create a gray scale image of a channel in a layer and make that the source. The destination seems to be all channels of a selected layer, or does one have to separate out those channels as well? The Channel Mixer is designed to specify a single channel as destination, but it appears the source must be in the same color space. Shouldn’t these two processes allow individual choice of source and destination channels in all color spaces? Are equations (Apply Image) and sliders (Channel Mixer) of equal value in practical applications?
I don’t think this exhausts these issues, but this post has already exhausted me. My compliments if you have read this far. If you want to know more about Margulis, use a search engine or post here and I will try to summarize what I have earned from a large corpus of writing.- Saijin_Naib, shojtsy, Fixx and 2 others
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A bit of history from an extended link crawl on Wikipedia and links therein. There was a proprietary program created ca. 2003-2006 called AutoStitch that automated the process of choosing how to blend the images into a panorama (http://matthewalunbrown.com/autostitch/autostitch.html). It's available from here in free demo versions; there were commercial Mac versions but the links on the above site say that they are no longer available, one as of this month. However, a license went to Serif and is presumably the ancestor of the AP stitcher. So there must be some Serif people who have an idea if manual intervention in this process can be useful. A commercial license adds capabilities but I can not immediately tell what software is using it.
I downloaded the demo Mac version from the above page, and it worked well on the lower 5 of my images in default mode after adjusting the output size (jpg). The horizons I think are somewhat better than the AP versions, though not perfect. There is a ghost image that would have to be retouched out. The dark shadows were also much improved.
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It's ok to use my images for that purpose. It's interesting how many stitching programs are listed in https://en.wikipedia.org/wiki/Comparison_of_photo_stitching_software and links therein.
And I imagine there are others serving special needs in science and engineering. The Hugin.app is a front end for a large collection of programs that seems to be European in origin but has a large world community that is comfortable with the command line and compile-your-own. The English documentation appears poor, but there are tutorials and perhaps better docs in other languages.
I was unable to run Hugin after the first try, but I expect I can learn enough to do that.
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Thanks for your suggestions. I will check the overlap and try to do better. But my pictures are shot in stolen moments while walking with others, so time to compose is rare and a tripod not workable. The iPhone panorama option for seascapes without a tripod can also produce wavy horizons that are beyond my ability to repair. However, the varied exposure issue in wide panoramas such as these seems to be handled well by the AP algorithms.
I try to make up for the limitations of my photos in the evening in AP, so my proposal is: are there some changes in the stitch options that might help users (not just me) make better pictures? My exposure to Hugin has made me realize how many subroutines go into action when one presses the Stitch button. The options available in that program, once one understands it better, include a choice of projections (spherical, cylindrical, architectural, many others), the ability to manually nudge the source images' locations, and the do-not-rotate option that I was originally seeking. Some others seem too specialized for general use. So the developers can ponder if there is enough demand to expose some of the stitcher's workings to the general public. I for one would appreciate it, since I'm not sure that Hugin can repay the investment in learning the GUI.
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Tried to upload files, queue kept stopping. I got all 11 prestitching originals up, plus a couple of screen shots on upload status from Dropbox. Flattened the three 60-MB stitched afphotos to 20-MB jpegs, but the Dropbox screen would get to 40% uploaded and quit. I can try halving the linear dimensions tomorrow or try to upload the files through the forum. You can try stitching these yourselves or wait for a second try. Here's what I was intending to post with the files:
I have placed the following image files in your Dropbox location:
Original 11 unstitched files labeled L1.jpg to L5.jpg (lower row) and U1.jpg to U6.jpg (upper row),
Stitched images from lower, upper, and both groups of originals [failed on 9/25/18]S1 AP-stitched lower group.afphoto/ or jpg
S2 AP-stitched upper group.afphoto
S3 AP-stitched both groups.afphoto
Discussion
All stitched files show rotation of horizontal lines and mismatch of details near the horizon. (Horizontal lines and a straight sea-sky horizon are clearest in the leftmost two original images.) The S1 lower row contains shoreline features below the horizon, and the S2 upper group contains sky with clouds above the horizon. It appears that there is more rotation in the group with sky and clouds.If this is not clear enough I will try to take another series with a clearer horizon, but I do not have immediate access to such a scene.
I attempted to explore an alternative stitching app by downloading Hugin.app from hugin.sourceforge.net. This is free and open source and is complex, and is also aware of projection, rotation and alignment issues. One stitching using default parameters gave an image that was superior in places to the above but not excellent. An attempted repeat led to a dead end that I attribute to not so great documentation of the user interface. If I make progress with this I will add a note to the thread.
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I have been trying to make a panorama from a group of pictures shot together that contain a sea-sky straight line horizon. Modifying the source masks as in the video "Tricky Panoramas" has not been helpful, and I realized (and demonstrated) that many individual pictures are rotated, and by different degrees depending on which other pictures they are stitched with. So:
Does anyone have a workaround for this situation? Or a third-party stitcher that does not behave this way?
Or should we ask Serif to add a feature to address this need?
(True, not all my horizons are perfect, but I checked them.)
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If anyone is still interested, or may come on the topic in the future, the answer to the question of how to create a gray-scale pixel layer from the current RGB image in order to blend it using some special blend mode, such as Luminosity, is as follows.
Open an RGB image. Choose the channel to convert from the Composite channels in the Channels panel (e.g., Composite Red). These have the eye and pencil icons on the right.
Right click on the channel of the same color among the channels listed with the original image's name (e.g., Background Red). Choose Create Grayscale Layer. The new layer will appear above the original layer.
Adjust the blend mode.
Incidentally, the preceding post's reference to PP5 should include Chapter 8 as well as 10.
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The Apply Image procedure that I am trying to reproduce in AP is described for PS in a video labeled "Chapter 04. The Apply Image Command" on the page
http://www.moderncolorworkflow.com/private-resources
and described in detail in Professional Photoshop (5th ed.) in Chapter 10, "Every File Has Ten Channels."
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Thanks, firstdefence and toltec, for your suggestions. I will review these tutorials and if they answer my questions I will post something more specific in this thread (may take a while). If @MEB is about, he answered a channels question a while back quite incisively.
Sorry for slow reply - I had notification on and thought I would get emails, but I had not realized there were so many options.
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This is long – my questions start in the third big paragraph.
After spending a couple of years trying to learn how to improve my photos in AP, I think I see some light along the difficult path in the form of Dan Margulis’s Professional Photoshop (5th ed.) and his other books.* His approach to color correction involves understanding human perception, color spaces, image processing algorithms, and means of rendering images in print and on screen. It should translate well to other image processing programs such as AP. I find his approach so persuasive that if I had the time I would get PS to pursue it. Right now, I need some help applying some basics to AP.
Two fundamental tools that Margulis discusses at length are curves and channel mixing. He gives many examples of color correction with curves in RGB, CMYK, and LAB that are easy to learn from. A minor issue is that he displays curves with dark on the right, whereas AP only shows dark on the left. These can be compared by mentally or physically rotating the curves 180 degrees. PS has a one-click control to flip them.
Channel mixing does not translate so well. The fundamental Margulis maneuver in PS is to choose a channel in RGB (e.g., the most contrasty), use the Apply Image command to create a BW layer from that channel above the image layer, and then use Luminosity blend mode to increase the contrast. Creating this layer from existing channels seems to involve only a couple of steps. But this does not work in AP, which seems to be set up only to blend two layers, not create a separate one. Also I can select a source layer but I don’t understand how I select the destination (the pixel layer I created to receive the channel). This has got to be trivial but reading Apply Image help does not seem to help. “Apply” button grays and becomes active in a way I have not figured out. Also it appears that the equations operate in only one color space, while PS allows blending cyan with RGB. Can someone help me see if my task can be done in AP? It’s got to be simple.And why are the Composite channels more functional (show, edit) than those of the other layers?
Although it goes beyond my immediate inquiry, it could be an important influence on the evolution of AP if, among those AP and PS users who are aware of Margulis’s work, there is enough interest to justify developing better user interface elements. (I already have a couple of ideas.) Many advanced retouchers are very enthusiastic about his writing (see reviews of his books on Amazon). Margulis and co-workers have also automated some of his more complex approaches using PS script actions, available through a freely distributed panel. This appears considerably more capable than the AP macros.
* Professional Photoshop: The Classic Guide to Color Correction (5th ed., 2006); Photoshop LAB Color The Canyon Conundrum and Other Adventures in the Most Powerful Colorspace (2nd ed., 2015); Modern Photoshop Color Workflow: The Quartertone Quandary, the PPW, and Other Ideas for Speedy Image Enhancement (2013). Somewhat pricey, but good value. I bought second-hand copies of the first book and the first edition of the second. One lacked the CD. I have not read the third, but there is plentiful information available online, including videos for most chapters.- Peter Heinrichs, Fotoloco, Fixx and 1 other
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Simon, apologies for no reply. Must have turned off my notifications. Too busy in interim to draft anything. To Simon and anyone else still following this thread: I have been looking over two books by Dan Margulis, Professional Photoshop (2006) and Photoshop LAB Color (2005). I bought inexpensive second-hand copies; one even came with the CD! These are the first books I have encountered in the image processing world that talk convincingly about why you would want to do various manipulations and that provide printed examples that show the differences in results and the curves or other techniques needed to get there. Furthermore, if you work to follow him, you will learn to develop your vision in several dimensions. His ideas can mostly be applied directly in Affinity Photo. However, his work has some limitations. Working in high-end letterpress since before Photoshop was created, he mostly likes to deal with an image and the process of making it into something that can be printed, i.e., he is concerned primarily with color quality and sharpness. He prefers global techniques to masking. He is mostly talking to experienced, regular, relatively advanced users of Photoshop, so he will only intermittently be directly useful to a newcomer. However, the second book, on the LAB color space, turns out to have several introductory chapters written for relative beginners that show that this seemingly advanced technology is actually quite easy to use for color correction and sharpening. Perhaps someone will be able to use him as a sort of model for an introductory work. Not everyone likes his writing style, but he is generally very clear, and has obviously put great effort into his study and teaching.
There's more about him online, including articles old and new: some links in this thread: https://forum.affinity.serif.com/index.php?/topic/22011--/&/topic/22011-learn-lab/?p=103168
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@AnnH
I think you will find the discussion at the link below useful. It has references to many free materials, video and text, and others, with some suggestions, e.g.: start small, practice much.
https://forum.affinity.serif.com/index.php?/topic/53381-how-to-start-in-affinity/
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It seems there should be a way to communicate directly, but I don't know how. I don't want to post a long piece here before editing it for coherence. I'm still short of an outline. Let's look into direct messaging via this forum, or you can use the email in my earlier post. Or I may have a piece worth posting in a week if other responsibilities don't prevent. I'm working my way through Simon's new course and may look at his earlier ones after the Foundations one. One thing I have found by looking at video tutorials by different people (I think the Affinity series is all by James Ritson) that they often do a similar task in rather different ways. Also I have looked at Photoshop books and Adobe help since the basic mathematical operations are the same even though details differ. Only one I found has the deep and broad perspective to be useful for Affinity; that is by Margulis, but though interesting to read it is at, at least, journeyman level and I am still mired in apprentice level after a couple of years reading and viewing tutorials. Practicing more would help, I know.
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Simon, I have been thinking about how to learn image editing software since I started using AP in the initial release. I completed your Solid Foundations but continue to be frustrated by a lack of materials that fit my learning style. Your recent YouTube video on patching the big frame image gave me some ideas that I would like to share (not now in final text form, may take a few days since it could reach several pages). If you would like to contact me directly, you can use lcorwin34 {at} gmail.com; if not I will probably post to this forum.
I bought the new course at the site discount but have not yet explored it.
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Just added this so I get mail if there is an answer.
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My images in Photos/exported PDFs are all pre-HEIC. Does this mean that one should not install High Sierra until Serif deals with this, or can old and new coexist? Please say more.
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On Quick Inpainting Crooked Horizons, this is useful but refers to tilted horizons. I have some truly crooked horizons from wobbly iPhone pans, and if there is a solution for those that doesn't involve hours of nudging I would be interested.
On Using Adjustment Layers on Masks, I'll save this for when I understand more, but for right now, what do you mean by 'to matte' in this context? ('Brush over the hair to matte it," 'hair is a little thin from the matting.') Not a paperboard border, not a non-specular surface, ... ?
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Though I came to this thread trying to find out what is meant by Matte, I would like to echo the OP's plea for more app feedback. I and other newbie contributors have often wasted time trying to do something that is not permitted for a variety of reasons, but nothing happens from the app. A little window with a hint of the error if possible would save some frustration.
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Thanks. I have achieved the most consistent results by using Merge Visible plus Rasterise to Mask. There still seems to be some inconsistency with how the layers behave for me; for example I found that just selecting a layer changed the displayed image appearance even though the check boxes were not touched (the change was sometimes irreversible if I remember correctly).
Affinity Photo Customer Beta (1.7.0.98)
in [ARCHIVE] Photo beta on macOS threads
Posted
I closed 1.6.7 and do not have any other builds anywhere, so I performed the control/launch/clear procedure and got to the same blocking window as before (below). I closed that with cmd-Q and trashed the virtual disk with the beta download but on launching get to the same display with a different background. Should I download again? There was a lengthy checking procedure noted in a window during the first attempted launch so it's not likely the app file is corrupted.