Control – & Control +, or the slider in the navigator pallette aren’t good enough for you?
Regarding pixelated views at varying zoom factors, that’s just something you have to live with. Changing file rez to combat this is just, well, wrong.
Derek,
How the mouse wheel affects zooming & scrolling has been discussed here quite a bit in the past, yet a search now turns up empty. In PS6, there was less consistency in how this worked, so Adobe changed things for PS7. It works like this:
Wheel Only = Zoom in/out if image is displayed smaller than image window such that no scroll bars are displayed. If one scroll bar is active, then the wheel scrolls the window in the related direction. If both scroll bars are active, the wheel scrolls vertically.
Alt+Wheel = Forced arbitrary zoom
Shift+Alt+Wheel = Forced interval zoom
Shift+Wheel = Forced scroll
With regard to your second question, if I read what you’re asking correctly, of course the resolution would appear to break up as you zoom in on an image. Zooming in has the effective result of magnifying the image such that fewer image pixels are displayed per screen pixel, hence an apparent "break up" of the resolution as you call it. The apparent resolution of an image as viewed on screen has nothing to do with the actual resolution of the printed image. On screen, all you need concern yourself with is the pixel dimensions of the image. If your image is 800×600 and you display resolution is as well, then your image will fill the screen. If the display resolution is 1600×1200 however, your image fills only 1/4 of the screen and zooming it in to 200% to fill the screen would effectively reduce the apparent resolution by 1/2.
Hope that helps,
Daryl
I would very much like to thank Mr. Pritchard for his help. Your comments were coherently express and succinct. I do not much mind so much being taxed for my inexperience but we all have to begin and move forward from there. And no, control minus while I stand at full attention facing west sliding the navigator controls while while humming my favorite hymn is not good enough. It’s that sort of logic that replaced a simple spin of the wheel with the aforementioned ACTIONS. And for anyone whose listening, there is nothing wrong with adjusting the rez as long as it suits your image. One beautiful thing about Photoshop is that the only "WRONG" maneuver is the misplaced stroke of the key that does not render the desired effect. Keep trying sir, maybe someday you can discourage a child.
Still,
The humble student
I fully submit that I have been put in my place, and hope to share in some of your humility.
Derek,
Thanks for the compliment…I’m glad I could help. Now, reading your latest post, I may be wrong but I continue to be of the impression that you are somehow confused about what resolution is. No surprise really, as that word gets thrown around quite a lot whether one is discussing scanners, printers, monitors, or images. So, take what I offer as redundant if it is what you’re already aware of; otherwise, maybe it will be of further help:
"Adjusting the rez as long as it suits your image" – That is absolutely fine to do. However, taken in conjunction with the context of your original posting’s "I have some pictures whose resolution greatly breaks up when I zoom in", I think you’re muddying the water some.
Adjusting the resolution of your image means to manipulate the physical number of pixels per inch (or cm) in your image. If the image is 100×100 pixels in size and if the document resolution is 100 ppi, then the printed image will be 1 inch square. Depending upon the display characteristics of your monitor, that same image could appear larger, smaller, or the same size on your screen. In fact, modern monitors do approach a 100 ppi resolution, so I’ll say that the screen image is the same size as the printed image just for the sake of this discussion.
To "adjust the rez" and make that same image more suitable for a photo-quality print, one will often hear a document resolution of 300ppi mentioned. So, if you go into the Image Size dialog, uncheck the Resample Image box and change the document resolution from 100 to 300 ppi, you will see that the print dimensions reduce to 0.33 inches square. Saving the file makes no physical change in the image dimensions, but the file does get tagged with additional information so that many applications handle it as a 300ppi image rather than 100ppi.
On the other hand, if you zoom out on the screen image so that it appears 0.33 inches square and then save the file, you have done absolutely nothing to the file at all. In fact, you shouldn’t even see the "Save" option available…it will be greyed out. All that you do when zooming in/out on an image in Photoshop or other similar applications is tell the software to manipulate the on-screen dimensions of the image…that’s it, nothing more. If you were to inspect the settings in the Image Size dialog, you would find all values remain intact no matter the zoom level being applied to the image. To restate your comment more "correctly", I would instead say that "I have some pictures that appear more pixelated on screen when I zoom in". The response to that would be "That’s normal, because you are magnifying the apparent size of the image on screen, thus spreading the image pixels farther apart."
So, just to help you keep things straight, I suggest you try and start thinking more in terms of "resizing" or "resampling" when discussing changes in resolution, and "zooming" only when discussing how your images appear on-screen. And, on the whole, I find it much more clear to discuss images with others by not even mentioning their "resolution" and instead talk strictly in terms of their pixel dimensions.
Resolution is a very simple concept to grasp once you get the hang of it and don’t let its overuse in so many different contexts confuse you.
Hope that helps,
Daryl
Thanks again, and I apologize to Mr. Slate if I ruined your morning forum perusal. I should examine another ripple in my problem though to anyone willing to help. I want to take an image, an image with a resolution of 26 (320×240) and greatly clarify the detail. I have seen enhancements done in film by others but I have no idea how to create such a valuable work. My appreciation in advance for the professionals and fellow students who offer assistance. Thank you, learning and working this program means a great deal to me. I KNOW you understand.
….to continue with Daryl’s treatise, that 100 x 100 pixel file will display the same size at 100%, on any given monitor, whether it is 100 x 100 pixels @ 100ppi or it is 100 x 100 pixels @ 300ppi. When Photoshop reports the percentage at which it is displaying a file it has nothing at all to do with either resolution or print size. It has only to do with the number of pixels in the file. A 100% view is displaying 1 file pixel for every screen pixel.
When the number of pixels in a file exceeds the number of pixels on a monitor then the image must be downsmapled in order to view the entire image at once. At some of these downsampling ratios there is a noticable rough or stairstepped effect, yet this is not a true indication of what you will see in print. Notice that when you cycle through zoom factors, like when you purposely reduce the image size even though it will all fit at 100%, these display artifacts come and go. So you know they are just that: display artifacts. 100% zoom is always a reliable view of what you really have in your file, though for higher resolution files, this means a rather enlarged view vis-a-vis print size.
Back to Derek: you say, "I want to take an image, an image with a resolution of 26 (320×240) and greatly clarify the detail."
OK, 26 what?
Doesn’t matter really, 320×240 is rather small and I assume you are working on images for display only. 320×240 will surely fit at 100% on any monitor. Why do you need to even be zooming on such a tiny file?
What IS the final use of your files? I am guessing not print. The final use determines the resolution that you should work in, not what looks best on the screen at this zoom factor or that.
How are these files originated?
As far as improving clarity goes, have you tried unsharp masking?
Derek,
"I have seen enhancements done in film by others " Hoping you are not thinking "CSI" here.
I got the sense that Derek was trying to have optimal image display at all magnifications within photoshop. Further I got the sense that he hadn’t quite made the connection that, as stated earlier, anything other than 100% magnfication in photoshop is an approximation of the image.
Changing your image resolution in any way, be it ppi or dimensions to display properly at all magnifications in Photoshop is an exercise in fuitlity and, frankly, uh… not a good way to think about things. It’s kind of like trying to brush the tooth of a Lion – dangerous.
If I’ve misunderstood, I apologize, but that’s what I’ve discerned here.
Forgive me fellow Photoshop user but your responses are extremely impressive to me. Whenever I have a question, it seems as though I always get responses from people who are seemingly qualified to build a Photoshop. You people should gather together and give Adobe some steep competition! Sometimes it’s a little dificult to grasp if I am honest but I am learning as I go thanks to you. Mr. Slate, the image I am trying to improve comes from an old home movie I have transfered to still using video editing software (not premiere). I would like to both transfer the image in print at full sheet(which I have not yet tried because I need two ink cartridges) and display the image full screen as if it were a new photo. Perhaps the original is beyond repair. Admitedly, the picture is of poor quality. I never thought, I suppose in my naivity, that Photoshop had a limit. I leave now disillusioned, questioning thoroughly whether the earth is round by having this belief shattered.
OK then, I think you’re out of luck then.
320 x 240 just isn’t enough to work with. That’s 1.066" x 0.8" @ 300 ppi. To expect to enlarge this to print full size on letter sized paper, even on a laserprinter that needs less rez than a high rez imagesetter, is to expect too much.
Unlike the Hollywood version where somebody taps at a keyboard and a totally blurry image, taken from space, resolves itself into a sharp photograph, Photoshop can add resolution but it has to guess at what color to make the new pixels. Image quality, generally speaking, will not improve that much. Basically, you can’t get blood from a stone. What you can do is take a very low rez image that will print out showing clearly the actual pixels in the image as little squares, and soften those little squares so they are not so pronounced. Then you can add a little sharpness if you think that will help.
Some claim that the resampling function from the Genuine Fractals plugin is superior, but I would guess that if you tried it, you would end up with a slightly more subdued version of really bad.
Try this experiment:
Open a nice high resolution image that you have saved somewhere.
Copy all and paste into a new document.
In either window, go into image size, check the resample box, and decrease the resolution by a factor of 8.
Then go back into image size, still with the resample box checked, and return the resolution to whatever it was to begin with.
Now compare the two images closely, like at 200%. You see what resampling way up does? Here you have an example of detail destroyed and how well Photoshop can recreate lost detail.
BTW, don’t sail too far out there or you will plummet off the edge of the world. Say hello to the turtle as you fall on by…
Great Reply! I know what I wanted to now and have a new weapon in my small arsenal of photoshop knowledge. You people, particularly those I converse with impress me. I only wish there was someone I knew personally or that Adobe offered ACE here in Houston. Thanks John, you’ve been a big help man.
