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martycon
24-11-2017, 4:58pm
When I got my 4k screen I was pleased that my lenses were sharper than I had thought. I was reasonably happy with my resizing routine, until I resized this image, with a horrible result. After some trials I tried a new routine.
After RAW development with its nominal preset NR and sharpening, I saved as .tiff lossless. I used Ps CC 2017 for some levels and brightness adjustments, then more NR, and a slight sharpen with Topaz Detail micro contrast enhancement 1. The crop was then made and saved as .jpg. The full image was then resized using Ps, resample and the bi cubic sharper options. Then saved as .jpg (10), and a small final sharpen with Usm set at 0.4mm and strength 50. The result is still disapointing.
How can I retain more of the detail available before resizing?

133466

133467

ameerat42
24-11-2017, 7:46pm
1. Is this just for viewing on that monitor?
2. What are the original pixel dimensions of the image?

I am angling for the reply "Don't re-size", where "-size" means "-sample",
but need some more info.

>>Main reasoning: That screen is already "re-sizing" your original image - whether up or down,
to suit its display size. If it's already a hefty pixel-dim image, like 15MPx and higher, the screen will
have to shrink it to fit. Who knows how the algorithms they use match up with the PS ones? Best you
might be able to achieve for viewing is to display (part of the) full size image.<<

gcflora
24-11-2017, 8:22pm
If you want to sharpen for web viewing then the following "trick" can help.

Step 1: Resize the image to about double what you want the final size to be. E.g. if you want a 1280x1024 image resize your original image to about 2500 wide
Step 2: Apply the sharpen filter twice (photoshop sharpen... if that's not available then unsharp mask will do just as well I guess)
Step 3: Resize to the final image size (1280 wide)

After step 2 it will look way over-sharpened but the final resize takes care of this. Also you may want to add a tiny bit of saturation (5-10) after getting to the final image size because sharpening can make the image look less saturated

martycon
25-11-2017, 12:27am
Craig thanks for helping. I am only interested in sharpening for forums at this site, with its specified max dimensions. I hope your sugestion still applies as it simple and quick.
cheers marty.

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Am thank you for helping. Reading your opening queries, I had to chuckle, because you do to me, that which others say I do to them. That is, answer what I thought to be a simple query, with specific questions.:D
1) I am resizing to satisfy this sites requirements, so yes it is for a wide variety of monitors. 2) The RAW image was 4640x3472. It was then cropped to 4203x2888. It looked fine to me at this stage, as shown in the crop which was not resized. On my screen the .jpg version posted is only slightly inferior to the .tif version which has not travelled to AP and back again. My screen, (is it still a monitor) has pixel dimensions 3840x2160 so for the time being I think it magnificent.
When resizing an image my recently downloaded version of Ps gives the option "resample" which I select.
Am, is your profession perchance as an engineer? Some folk consider us to be pedantic when we are only seeking unambiguous answers. I look forward to your further advice.
regards marty.

ameerat42
25-11-2017, 8:30am
About monitors...
1. A 4K TV is still a "monitor".
2. I think you can expect to see differences in the same image on different monitors.
3. (I don't know, but) TVs may be optimised for moving images rather than stills.

General sharpening, etc...
Well, I don't know what you think about the sharpness of my images attached to AP,
but there is a limit to what you can expect from an initially good image.

Certainly, too much re-sampling and sharpening will shake up the image info and
sometimes make it a worse image. For this reason I try to do as little to the image
as possible. You might try along the lines:

-If you can crop away some of the original image, do so, then try a single re-sample
to the desired size in pixels - 1200 on a side. (Yes, it can be SQUARE, so there is no
need to invoke "long" side (or worse, "longest":eek:). Use just "Bicubic" re-sampling,
and do any sharpening afterwards. (Because you're doing a single, controlled action.)

-"Save as..." the result at jpeg quality 10* at first, then, while keeping the file OPEN,
check the file size. If it exceeds the maximum 400KB you will have to decide between
resampling the image down a bit more (say to 1000 pixels), or reducing the jpeg quality
a bit more (upping the file compression) when saving.

NB: If you keep the file open, you can use the History** (of your actions) to go back and
restore the full file info to, say, before the first re-sample. From that point you may try
1000 pixels. Similarly for file compression when saving. If, however, you close the image
and then reopen it, you are reworking previous work.

On other Qs (not in order)...
No/yes/I don't know/only on Fridays after 4 PM...:p

*Quality 12 (maximum) usually results in pretty big file sizes. At a(n absolute) pinch I have
gone as low as 8, which is the lowest "high" value. You can compress away fairly freely if
your image contains lots of bland monotone, like blue sky, walls, etc, but not when there's
a lot of detail.

**In your PS preferences, set yourself a generous number of history states, like 35-40.

Glenda
25-11-2017, 11:34am
It sounds like you are using 'save for web' option. I prefer to do it a different way.

Take your jpeg into Ps, then image > size > change the larger dimension to 1200 pixels > ok.
Ctrl J to add a new layer >filter > sharpen > I use unsharp mask > 100% - radius 1 pixel - threshold 0 > ok. Depending on how much sharpening you have already applied to your image this can be way too much, just play with your opacity slider until it is how you want it. Mine tend to range from 50 - 75%. I also change my blending mode to luminosity so it doesn't affect my colours. Check image - mode - you need to be in 8 bit to preview size when saving. I also edit - convert to profile to change my editing colour to sRGB. Then file > save as > jpeg. Click the preview box to see the size and reduce accordingly.

The first time you do this it will take a while but if you are happy with it, just record an action and then with one click it does all this in a couple of seconds. In my action my sharpen layer is a smart object so I can change it if necessary and it stops just before I do the save as step so I can change the size as necessary.

martycon
25-11-2017, 12:04pm
An I like your enigmatic way of honestly answering questions. Back to the subject. When resizing I have three bicubic options, "Bicubic sharper Reduction", appears to be the most appropriate. I will also experiment with "Bicubic Smooth Gradients" Your detailed reply is muvh appreciated.
regards marty.

ameerat42
25-11-2017, 12:16pm
Your version of PS may have different options from mine (CS2). It only has
three Bicubic options: "plain", Smoother and Sharper. Again, I'd steer away
from the sub-options of re-sampling for better sharpening/blurring methods.

- - - Updated - - -

In addition...
...sharpening algorithms rely on "edge" enhancement. An "edge" is (AFAICT)
any significant change in contrast in an image. If you want an idea of what
PS treats as edges, run the - it might be different for you - Filter-Stylize-
Find Edges or Glowing Edges commands.

Running a lot of sharpening can cause other artifacts to show, like grain in
smooth skies, and haloes around darkish areas. There are lots of ways of
minimising these, but...

martycon
25-11-2017, 12:24pm
Glenda my nature is such that I seldom do anything the easy way, which rules out save for web. I am doing virtually the same as you, but resizing as a tiff file, and then saving as .jpg, then a USM sharpen at 0.4 and 50%.
Your use of a layer and blending mode for sharpening of the reduced image is interesting, and has obvious merit.
I have yet to record an action, or process multiple files. I shall give it a go sometime soon.
Your advice is much appreciated.
cheers marty.

John King
25-11-2017, 1:51pm
Marty, may I suggest that you work your way through this, if you haven't already:

http://www.cambridgeincolour.com/tutorials/image-sharpening.htm

Gazza
25-11-2017, 2:57pm
You could really slack (like me) and download Jimmy Mac's (http://www.shutterevolve.com) panel for PS.
There's a bit of learning involved if you want to take advantage of all his features...but it certainly speeds up sharpening & saving when posting here at AP. (a few clicks)

There is a free panel, but I have no idea what that does?

There's also plenty of other people out there offering simple to use Add-on's/panels for CC2018 as well.


Cheers - :beer_mug:

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While grabbing the link I spotted he has 25% off (black Friday thingy...) 6 Hrs to go at time of posting

martycon
25-11-2017, 10:37pm
Thanks Am, I will look at edges as you suggest, it will be an interesting exercise. It is very apparent that effective sharpening requires finesse.:nod:
regards marty.

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Thanks John I have bookmarked that link and will return to it. I have much homework to absorb. Fortunately I find it interesting.
regards marty.

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Gazza the concept of a "panel for Ps" new for me. I shall investigate this also. Thanks for the thought.
cheers marty.

Glenda
26-11-2017, 8:02am
You could really slack (like me) and download Jimmy Mac's (http://www.shutterevolve.com) panel for PS.
There's a bit of learning involved if you want to take advantage of all his features...but it certainly speeds up sharpening & saving when posting here at AP. (a few clicks)

There is a free panel, but I have no idea what that does?

There's also plenty of other people out there offering simple to use Add-on's/panels for CC2018 as well.


Cheers - :beer_mug:

- - - Updated - - -

While grabbing the link I spotted he has 25% off (black Friday thingy...) 6 Hrs to go at time of posting

You reminded me of a job I still have to do. Googled the instructions from Jimmy Mac and procrastinated. The one click resize button is definitely a joy.

Gazza
26-11-2017, 8:22am
You reminded me of a job I still have to do. Googled the instructions from Jimmy Mac and procrastinated. The one click resize button is definitely a joy.
Just in case you've lost his email....:url: (http://www.shutterevolve.com/raya-proinstamask-fix/) (it was a while ago...:grinning01:)

Glenda
26-11-2017, 10:03am
Just in case you've lost his email....:url: (http://www.shutterevolve.com/raya-proinstamask-fix/) (it was a while ago...:grinning01:)
Thanks Gaz - I either didn't receive the email, or more likely accidentally deleted it while we were away.

Mark L
26-11-2017, 8:27pm
Regardless of all of the above I think resizing to accommodate posting directly to AP is problematic. I got so unhappy with it that I eventually relented and started linking photos at a larger size via flickr. It's easy to do. I post to flickr at 2000 on the longest side for landscape and 1000 for portrait. Even at this small size they appear much better than posting at the maximum size allowed and directly posted to AP.

martycon
26-11-2017, 10:26pm
Mark I recon that is a good comment, and now know why you do that.
cheers marty

Cage
27-11-2017, 12:46pm
What Mark said ^ . :th3:

Gazza
27-11-2017, 1:19pm
Regardless of all of the above I think resizing to accommodate posting directly to AP is problematic. I got so unhappy with it that I eventually relented and started linking photos at a larger size via flickr. It's easy to do. I post to flickr at 2000 on the longest side for landscape and 1000 for portrait. Even at this small size they appear much better than posting at the maximum size allowed and directly posted to AP.


What Mark said ^ . :th3:
Marty, you could also use your free 'Portfolio' site/space that comes with your CC subscription to host the larger image size...so many ways to 'skin-that-cat' :D

ameerat42
27-11-2017, 1:29pm
Or, if PP is your thing, brush uPP on the technique of re-sizing:confused013

ameerat42
27-11-2017, 3:08pm
...Some time later...

Two more things related to this thread:
1. Sometimes when cropping a distant subject, it is often sufficient to just
crop it to (or near to) the maximum size allowed on AP - 1200 pixels. This
will yield a 100% crop - ie, NO re-sizing required. That's what I did for this. (http://www.ausphotography.net.au/forum/showthread.php?155252-The-2017-Members-Challenge-Week-48-Tiny-Creatues&p=1435532#post1435532)
It happens to be a 784px × 1,176px crop of the full sized image.

2. When re-sizing (ie, re-sampling), an even number reduction would be
more accurate in rendering detail than something arbitrary. Ie, re-sample
to 1/2, 1/4, 1/8 of the original image size, rather than, say, 1/2.5 or so.

For the example in point 1 above, if I had to re-sample the whole image to
1/4 it would end up the same pixel size as that image, since my camera
outputs 4704 x 3136 pixels. 4704/4 = 1176.

martycon
01-12-2017, 8:01pm
Am, I sort of enjoy PP as part of the creative experience, and have brushed up, and got better resulst thanks to you and all who have helped. I have noticed that texture of the original makes a diference, so process may need to vary acccordingly.
regards marty

Mark L
01-12-2017, 9:40pm
After resizing try sharpening again by a fraction.

martycon
01-12-2017, 10:00pm
So many options to review, there truly more ways of killing a cat than by drowning it in milk.

ameerat42
02-12-2017, 8:02am
That would have to be wholly cow's milk, I suppose?