I'm scratching my head over why the Photoshop (v 24.0.1) posterize filter behaves one way in 300DPI and another way in 72DPI. The two results are very different. I really like what it does in the lower resolution, which is much more textural than the high res treatment (which is kind of bland) – but my project is for print so I have to work in 300 DPI. Does anyone know how I can achieve the effect of the 72 DPI image below in the higher resolution? I've tried playing with the posterize options, but can't seem to get the more raw, dotted look.
Really appreciate the help!
PS: Mac user / Monterey 12.6
Do you mean Image > Adjustments > Posterize applied as a Smart Filter or the Adjustment Layer?
Could you please post screenshots taken at View > 100% with the pertinent Panels (Toolbar, Layers, Channels, Options Bar, Edit: Properties, …) visible?
Hopefully this will help you help me.
There's the base image, which is duplicated in a new layer. From there I go to Filter Gallery > Artistic > Poster Edges.
In 300DPI mode it does one thing. In 72 DPI it does another.
PS: If I use Image > Adjustment > Posterize, it just looks bad either way, and I've not shared a shot of that. Sorry to have used the wrong term "posterize" when really it's "poster edges".
What are the pixel sizes of the two examples? Ppi is irrelevant.
Are you viewing both at 100%? At 100%, one image pixel is represented by exactly one physical screen pixel. It's the only way to reliably judge noise and sharpness.
Please forgive me for pointing all this out but
• You didn’t mention the Filter you actually used in the original post.
• I asked for screenshots taken at 100% magnification, not 33,3%, 300% or whatever.
• Digital pixel images do not have »dpi«, their resolution is given in ppi (or ppcm).
If you apply the same Filter with the same settings to two significantly resized versions of the same image expecting identical overall results seems unreasonable. (There are exceptions, Average for example should yield comparable results.)
The settings that represent pixel-values need to be adjusted, but as »Edge Thickness« is limted to 10 this won’t work out in this example.
Edit: There are additional differences, but the pixel settings should be clearly understandable; suppose you apply a Gaussian Blur with the same settings to an image and a 24% downsized copy of the image – a different overal appearance would not be unexpected.
I appreciate your time – sorry to be such a disappointing questioner!
1. I already apologized for not using the name of the filter out of the gate.
2. My screenshots of the filter being applied are at 100%.
3. I refer to DPI because my end goal is print, as originally stated. Switched to PPI the larger image here is 3174px X 4019px / 300 PPI.
And yes, I understand the filters are reacting to a different number of pixels. The bottom line of my question was if any one knew how to achieve the grainier, more raw poster look (as seen in the smaller image) in the larger image – which the available value adjustments don’t seem to allow. Any ideas? If not, I'll just get creative.
648px X 792 px / 72 PPI
If the low pixel version gives the result you want, why not use that and apply the filter - then scale the result?
Dave, beause you can't scale up for print; a lower resolution gets super pixelly when enlarged.
I'm experimenting though - enlarging the lo pixel art and using it as a layer in the high res file, so it shows through but isn't the main thing. The end result will be different - but maybe better! 😉
Have you tried using different algorithms for scaling? It should not get 'pixelly' as long as you don't use nearest neighbour. You could also add some slight blur and contrast enhancement to smooth further if required.
I would not normally recommend scaling up, but in this case where you want the qualities provided by poster edges on a low pixel file, it may work .
2. My screenshots of the filter being applied are at 100%.
Are you sure? See screenshots of your screenshots.
And yes, I understand the filters are reacting to a different number of pixels. The bottom line of my question was if any one knew how to achieve the grainier, more raw poster look (as seen in the smaller image) in the larger image – which the available value adjustments don’t seem to allow.
You could try combining multiple Filters to get closer to the intended result.
I was conscious of capturing it at 100%. Not sure why you received them differently.
It is indeed not relevant, but I am kind of stubborn and they were not at 100% magnification.
Yes, I can see that you are! 🙂 And that's fine; I'm known to be picky on things too.
I don't understand why they didn't show at the proper %, though, since the images were at 100% when I snapped the screenshots of ScreenShot_300DPI_with_filter and ScreenShot_72DPI_with_filter. Ahhh, but I see you were looking at the nancy png (not sure which one of mine is called Poster Edges) which I had just tossed in as reference and didn't think important – I thought you were only interested in the filtered shots. My bad on that one for sure.
By the way: You may want to convert the Layer to a Smart Object in order to be able to work with Smart Filters instead of destructively applying the Filters.
That way it is easier to experiment with Filter settings without having to step back in the History or creating new duplicate Layers.
Yes, for sure. Sometimes do that.
There's always going to be some issue with this - because of a combo or resolution and content and more.
One way to scale it up (again, depending on the content) is to do it very incrementally. Try Preserve Details or Bicubic Smoother - but if you want to rez up 200%, first do 110%, then 120%... etc. It does a better job with smaller increments.
ALSO, you can maybe try resizing the lower rez image up, and aligning it on top of the higher rez image. Then, use a blending mode that may allow for the darker tones, and not apply the lighter tones - like... Multiply. In order to have a minimal effect on the lower layer - this would be incremental, too. One layer in maybe 10-15%, and then duplicating that layer.
Unsure if that'll fix it, but that's how I'd start out trying...
EDIT: I just tried it on the low rez screenshot I got on here, and it was best with Darken as the blend mode...
Dave and S_Gans - thank you. We're on the same page. I think this is a "where there's a will there's a way" scenario! Also in my favor are the other layers of art involved - watercolor background, an abstract (it sounds nutty, but makes for cool results)... which means the intention is not to look ultra refined (and that low-res posterization makes it all come together - and yes, am trying with the different blends). Even so, I am being very careful that it doesn't look pixelly! So far so good; fingers crossed.