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Dazzler

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Posts posted by Dazzler


  1. They are actually positioned correctly, it's a visual thing that happens due to anti-aliasing of the edges of the layer.

    To solve this, click on each of the green layers and click the cog icon at the top of the layers panel. Then in the dialogue that pops up, select the coverage map and drag the left hand point up to make a straight line across the top and it'll solve your issue.


  2. Another method similar to Murfee's is to duplicate the layer you want to clip for each element in the group and nest those duplicated layers inside each item in the group so each is clipped by the item you've nested it within. You can then use the 'lock children' tickbox in the context bar to prevent them moving. that way you can move the elements around within the group and it would work in a more 'live' way. Again, not ideal but it would work.
     


  3. I'm not sure if there's a way to do the same thing in Photo.
    Here's a workaround that might help though?

    1. Ctrl + click on the thumbnail on the group layer - this should give you a selection around the edges of the items in the group.
    2. Select the pixel layer that you want to clip.
    3. Choose Layer > New Mask Layer - This will mask the pixel layer with the selection.

    I know that will not be live updating thing, so if you adjust the items in the group and move them around you'd have to delete the mask and repeat the steps. It's only a few seconds of extra work though.


  4. Odd, the method I said should work, as I did exactly what I said in a new document to make sure ... worked fine. Make sure you create the artistic text first, then switch to the gradient tool (make sure it's the one from the tool bar on the left (looks a bit like a cd with a diagonal line running out of it). Garry's suggestion is equally valid, although maybe has an extra step in creating a rectangle.

    Clipping is simply a term used to describe a mask that cuts off some of the image. So in Garry's example there's a gradient filled rectangle, which has been placed inside the text layer (this can be tricky if you are new to Affinity, but you drag one layer into another - but depending on where the blue highlight sits when you are dragging tells you how it is going to combine those two layers - you want it to sit to the right and just below the text layer) - doing this makes the text into a clipping layer - only reveealing the gradient below where the text is.


  5. Easiest way ...
    1. make your artistic text
    2. Select the gradient tool in the left hand tool palette.
    3. With that tool selected drag across your text to decide the angle of the gradient.
    4. Choose colours at the points along the line - it starts with two but you can add new ones by clicking on the line or select existing points, then choose a colour from the colour palette.
    5. Enjoy your rainbow text!
     


  6. To make an even more realistic shadow you can use Photo to soften the furthest parts of the shadow using Field Blur and setting two nodes within that with one node near the feet and the other at the extremes of the shadow. the node near the feet would have minimal blurring, whereas the furthest one would have more. That mimics the way that shadows are more diffuse when they are further from their source. For the job in hand it's probably better to not do this and keep the sharp edges as stylistically it fits better with the flat graphics.


  7. There are some great suggestions here. One thing that I often see done and disagree with though is the use of grey as a shadow colour. Unless it's for stylistic purposes, shadows are never grey - they are black with an opacity to allow the underlying colours to show through (the result may be grey if they lie over a white surface - which is presumeably why people use grey). Stronger shadows have a higher opacity, softer ones are more transparent. Using grey brings an unrealistic look. Putting a grey shadow across a black background actually lightens the black, something that doesn't happen in real life - shadows should never lighten anything.


  8. So working with three images whereby I've loaded the same image twice and then chosen a different image and put them into a stack, the median does exactly as you'd expect and disregards the image that is different. However, hiding one of the duplicated images, leaving just two images that are different seems to reveal a picture whereby some pixels are selected from one image and some from the other almost like there's some weird masking taking place (which is kind of expected to some degree). So it looks like it's choosing one or the other image to show for each pixel. How it's deciding that I'm not sure, but a true mathmatical median should be taking into account that there's an odd or even number of samples, and if it's even, taking the two middle ones and doing a mean between those to arrive at the result. Would that be useful from an imaging point of view? I'm not too sure, but it's kind of interesting what is happening - could be useful as an effect maybe?


  9. Interesting. Looking at the docs, it suggests that median removes content that is not consistent in each image - suitable for object removal and noise reduction. So I wonder if there's some extra calculations in play there that makes it more suitable for that. I expect they've taken a median calculation and expanded it to suit that purpose? I'm only guessing though. Not sure how it could really work properly with two images.


  10. 16 minutes ago, R C-R said:

    I just did a quick check & I apologize for the fuzzy jpeg screenshot, but this is what I am talking about:

    1830137607_blueedge.jpg.de3e6627257c0d90699ccc6a82518fd7.jpg

    When I compare that to the 3 individual channel views, I don't see enough overlap to explain why it is there in the All Channels view.

    That's the green channel's edge - the green is behind the transparent blue channel. You can clearly see it joining the green unobscured layer on each side. It's also doing the same nearer the middle. Remember that the individual channels on this are normalised to the height of the chart, so when you view the green channel it gets stretched upwards, but it's the same shape as it is in the combined view (make sure you click the fine view - it looks slightly different in course view) - just stretched.


  11. 2 minutes ago, R C-R said:

    Try it with a photo or original artwork when one or more color channels does not go all the way to the top. Also, the differences I see between the Histogram & Levels windows persists whether or not the histogram is set to fine or coarse, & when the Histogram window is adjusted to match the Levels display width as closely as possible.

    The Layer checkbox is not ticked on the Histogram panel -- if I do that with the Levels window open, the Histogram display shows nothing. Does that not happen for you?

    The layer checkbox just shows the histogram for the layer you have selected, so depending on what that is it may be blank, or might just be normal looking histogram.

    I've found an image with varying heights between the normalisation, but still my graphs match well with the levels ones. I pulled one out of unsplash using the stock function - https://unsplash.com/photos/q3o_8MteFM0?utm_source=Affinity Photo&utm_medium=referral

    How does that one work for you?


  12. 31 minutes ago, markw said:

    Hum… So can someone give an actual real world example where seeing this RGB overlap in  AP’s Histogram is useful ?
    Right now it seams to me, that in terms of usefulness while editing and image, that blue overlay of RGB overlap might as well be telling me how much rain fell today.

    I would refer you to R C-R's link to the cambridge tutorial in his post above. That explains a bit about it. There are some uses, mainly to detect clipping and contrast issues.


  13. 14 minutes ago, R C-R said:

    Except that you often can't do that because each view is normalized separately. Besides, even when that works it does not explain the bright edge in the All Channels view.

    As for the white area, compare the Histogram panel display to the one in the Levels Adjustment window, which still has a white area. Try changing levels there & then compare it to the histogram. Something still isn't right because they don't match up, whether comparing the Master vs. All Channels display or to any of the single channel views.

    Ok, on mine the graphs are hitting the top so any normalisation is having no effect so they match my composite one exactly. 

    As for the levels histogram ... mine are matching up well - obviously my levels one is a wider window so is slighly stretched in comparison and I did click on the little exclmaimation mark in the normal histogram to make it render more accurately (if you don't do this you may see an extra spike or two that shouldn't be there as it only renders a course histogram for speed). Comparing the master to all channels or individually mine are matching as far as I can tell and my eyesight allows!

    Maybe there's something else at play here? You don't have the layer tickbox selected on the main histogram do you?



     


  14. 29 minutes ago, R C-R said:

    Obviously, there is only one channel shown if you set the display to show only one channel (which BTW could be any of 4 channels for a CMYK document) so I don't understand why you think that is significant. Regardless, it does not explain the bright edge on the light blue part in the center of the screenshot histogram -- if the light blue is just a transparency blending effect of overlaying the color channels, there is nothing I can see that would explain that. Do you? 

    All I was trying to say by flipping between the channels is you can clearly see the way the edges lie for each channel, then when you compare to the combined 'all channels' view you can match each to it's repsective colour chart in the combined view, then you'll see there is no imaginary fourth area, it's just where they overlap. If you don't believe me take a screen grab of each individual colour, then composite them together with some transparency and you'll get the combined view - stacking them red at back, green in middle, blue on top.

    I agree a luminance value would have some use, I'm not saying it wouldn't, and probably more so than the individual channels, but it's definitely not the same as the white area that looks like it used to highlight where all three regions were combined which is somewhat misleading to say the least. I can see why they removed it.


  15. 3 minutes ago, R C-R said:

    Look carefully at that screenshot. Note that there is a bright edge at the top of what is circled in red, just like the bright edges for the red, green, & blue channels. If it is nothing more than the overlap, why is it there?

    I see the edges, and yes the combined colour makes a light blueish colour, but if you did as I said and flipped through the channels you'd see there is no fourth value being presented there. The reason for the transparency is so you can see all three channels against each other.

    The histogram is something I've had great difficulty with when teaching people how to use Photoshop. It's not that I don't understand it, it's that it doesn't actually make a lot of sense unless you know what exactly you're looking at. People see is as some sort of brightness curve, but it's not that at all. It's a screen estate measurement. It's really hard to explain becuase really there's not a lot of point in that information apart from to tell you if you have no values happening at the ends which could suggest a lack of contrast in your picture, and as I said previously, not all pictures need a white and a black point. It's not a case of the ends should definitely be at the bottom either. As I said read the y-axis as 'amount of screen taken up with this value' and you see how weird a measurement is actually is. It's easy to calculate from a programming point of view which is why it gets added.


  16. 3 minutes ago, R C-R said:

    There very clearly is a light blue -- just look at the screenshot in the reply above by @walt.farrell & what he circled in red. If it is supposed to be "the overlap/addition of the RGB channels" then why does it dip so low toward the right where red & green peak?

    We need a clear & simple explanation of why it is there, whatever it is, & also if it does not represent luminosity (or luminance) why the histogram does not include one or the other.

    No there isn't a light blue. It is simply the overlay of the colour channels. The dip you are talking about is clearly the blue channel. Just open Photo and grab a photo and flip between the three colour channels in the histogram and you'll see that it is simply a transparency on the three channels and where they overlap you get the combined colour. Nothing more than that. Luminosity is roughly going to be the chart ranging from left to right, not upwards in the histogram as you might expect. ie. A full white image would simply be a spike at the very right hand side of the histogram, that would be full luminosity across the whole image - not a line going across the top of the histogram as you might be expecting.


  17. Here's some things to try if you are wondering quite what the histogram shows.

    1. Fill the entire screen with a flat colour (make a rectangle and choose a fill colour). Now look at the histogram. You'll see three peaks at the RGB values for that colour. Now adjust the contrast quite a bit - what happens to the colour and the histogram?
    2. Fill the entire screen with a black to white gradient in the same way - now look at the histogram. Should be a fairly even line across the top of the histogram.
    3. Place a colour image - then convert to black and white and compare the histograms. Now, on the black and white picture up the contrast to max.  You'll probably notice gaps appearing in the histogram where the values are getting pulling apart from each other. What happens when you do a threshold adjustment? Now flatten the image and gaussian blur the result. How does that look?
    4. Take a photo, look at the histogram and then do a colour balance whilst looking at the histogram and see how it affects it. This may be more apparent if you do it on a black and white image.
    5. Take a few really nicely shot stock photos and place in and look at the histogram. Do the histograms appear as you expected or not?


    I'm not saying there's no point in having a histogram, but you need to know what it's showing you before making decisions based on that info. It's literally counting pixels that have that Red or green or blue value depending on which channel you are looking at and at what point along the graph. Simply doing levels or contrast to pull the values to just inside both ends of the histogram is not always the right thing to do. It's generally a good idea to do this but context is very important. Not all photos should have a white or black point, most should but not all.


  18. 2 minutes ago, R C-R said:

    I think it would be more accurate to say that it shows brightness rather than intensity, but either way the switch to the light blue color makes no sense to me. If anything, it suggests there is some connection to blue levels, while white does not, so why change it?

    Also, why is the background in the dark UI mode black? That just makes it harder than it should be to see the blue channel info. 

    As pointed out by James Ritson, there is no light blue,  it's merely an overlap of the three channels that is producing that colour - the old method of showing white where they overlapped has been removed. As far as I can see the overlap means nothing at all.

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