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08/06/2002 08:41:26 PM · #1
Okay, this time without mentioning the picture I submitted....

One of the recurring comments was that the picture was badly out of focus. The original was not, nor do I see a badly out of focus picture on my screen when viewing the picture I submitted. Though I have some ideas as to the various reasons why, I suspect that one of the biggest possibilities is that when I reduced the file to meet the <=150k, I lost a lot of resolution. One of you wrote: "it is beyond being 'artistic'."

So then I thought, "Well, okay, I'll just take the 150k file and sharpen it." Unfortunately, doing that caused the file to more-than double (344k).

Is there a way in Photoshop to save it with the same clarity and sharpness AND to a specific file size? I couldn't find it.
08/06/2002 09:07:15 PM · #2
What file size is your original one? Do you use superfine mode? I just have paint shop pro 7 for editing and don't notice that much difference when I lower my file size to fit less than 150k. If you have photo shop 6.0 you should be better off than me. As far as the artistic comment goes just ignore it for it is just a snobbish remark like comparing apples and oranges. Just keep taking pictures for you can only get better and best of all you only have one person to please and that is you.
08/06/2002 09:22:56 PM · #3
I have PSP too and am having trouble resizing. I've gradually found out that resizing down with bicubic mode gives you an awful case of jaggies. The best picture I've shot to date was selecting the 150 size area out of a 20 bit picture. Next to no resizing at all. just level 1 or 2 compression. always do an unsharp mask just before compression.

For what it's worth. can't afford Photoshop. aelith
08/06/2002 09:34:36 PM · #4
O.K. this would be a great time for the newbees here (me) to learn what "sharpen' and bicubic mode are for and do. There was a comment on my entry too that said perhaps "sharpen" would help. Then again, maybe save this for a different thread?
Thanks!
08/06/2002 09:38:46 PM · #5
Flipper what photo editing program do you use?
08/06/2002 09:53:06 PM · #6
what is the difference between sharpen and unsharp mask? I've been using it and have no clue if it is helping my picts or not.
08/06/2002 09:59:45 PM · #7
Bob:

Thanks for the reply. Yes, I have been shooting in RAW mode, so the original file size is 2meg and when covert to tiff, 11meg. For my picture, first I cropped, then I hued and sharpened (using unsharpen mask).

As far as the comments goes, I don't think the evaluator was intentionally mean, he/she was just making a candid observation. I looked at dpc using another computer whose monitor was set to a much lower resolution. I have a feeling that is also part of the problem for some that are viewing dpc entrants' submissions.

I downloaded my own submission from dpc at work and tried sharpening it. While the submission was 149k, applying sharpening to that increased it to 344k. So my original question is still baffling me: How do I submit a sharp, clear and detailed picture without exceeding the file size limit? Since others are successfully doing this, there has to be an answer that works.

Bart
08/06/2002 09:59:49 PM · #8
The sharpen filter gives you no control over the "amount" of sharpening done, it just sharpens the image by a preset amount.

Unsharp mask, on the other hand, gives you control over the amount of sharpening you apply. It does take a bit a practice to get used to.
08/06/2002 10:02:00 PM · #9
Hi Terry,

I'm also new at this and I just recently learned how to do it. Rather than take up a bunch of space here, do a search from yahoo using the keyword phrase "unsharpen mask" You'll get several hits. Here is just one of them.

//www.dpreview.com/learn/Glossary/Digital_Imaging/Sharpening_01.htm
08/06/2002 10:05:10 PM · #10
TerryGee,

The term "Unsharp mask" comes from an old darkroom techinique wherein a blurred film negative of an image is composited with an film positive. The blurred negative serves two purposes: it eliminates some noise in the image, and it also makes the edges in the photo more dominant.

A normal sharpen filter basically increases the contrast everywhere there is a difference in color between two pixels-- sometimes exaggerating any noise or other artifacts in the photo.

An unsharp mask filter only increases contrast in the edge areas of an image-- and hence it usually gives much better results.
08/06/2002 10:38:05 PM · #11
Sohr - Thanks for that - well put Now I understand its use much better.
08/06/2002 11:02:23 PM · #12
OK focus, lets talk about focus:))

One way I found to get good looking pictures at 150k is to first reduce the size in Photoshop, then save them for the web. First, go to Image > Image Size in Photoshop, or Image > Resize > Image Size in Photoshop Elements and enter 6 inches in the largest dimention with 72 Pixels/Inch Resolution (Be sure you have the 'Constrain Proportions' and the 'Resample Image' check boxes checked.) Then, no matter what size camera you're using you'll have a file size of about 400k or so. Then when you File > Save For Web, you won't have to compress so much and you're photo will look great.

On the subject of sharpening, that should always be the **last** thing you do before you reduce the size of your picture and save for web. As you found out, when you try to 'improve' a picture with JPEG artifacts in it by sharpening, all you do is sharpen the problem:) There should be a turtorial on the Unsharp Mask posted here soon.

As for not being able to afford Photoshop, try Photoshop Elements. It's been selling for US$65-70 here lately, and as a new version is coming out at the end of the month, the old one might go down even more. The program has everything you need for these competitions, I use it a lot when I don't feel like dimming the lights all over town just to color correct and re-size.
08/06/2002 11:49:17 PM · #13
Paul,

Thanks for the info. I''m not the one who mentioned not having Photoshop. I got the version that was included with my camera. I have been using "Unsharpen Mask" and have gotten relatively good with it, it was just the constraints of this site that baffled me.

Bart
P.S. I looked at your profile & noted you are in WA. Nice place. I visit about once a year to see relatives. This past March was very tramatic for me, I buried my 72-year-old father. He lived in Snohomish. I took several scenic pictures while there as a memorial. It snowed the day he died.

* This message has been edited by the author on 8/6/2002 11:49:31 PM.
08/06/2002 11:54:39 PM · #14
Just about everything I've read on the subject indicates not to sharpen until after level adjustments and resizing. Resizing can soften a picture. What you don't want to do is sharpen, resize, and then sharpen again.

There is a program called qimage (www.ddisoftware.com/qimage) that can apply filters for level adjustment, color correction, unsharp mask, etc. to an unaltered original. It can get a bit slow to process an image since it has to reapply the filters everytime you view it, but it's great for resizing as it uses the Lanczos algorithm, which is much better than the bicubic used by most programs. It also knows the proper order to apply filters, so when saving an image to 640x480, it will save unsharp mask for last. Photos that I've resized with qimage have come out looking just like the larger version, but a lot smaller of course. It is also great for printing as it can print an image at any size with cropping options. It can also auto-fit as many prints as possible on a single sheet of photo paper.
08/07/2002 12:01:01 AM · #15
Gene,

Thanks. I'll keep that in mind.
08/07/2002 12:06:21 AM · #16
I think there is a significant difference between RESIZE and RESAMPLE. It's difficult to understand the question that has been asked because of this...

In photoshop, I prepare my image at full resolution... make any necessary adjustments to color, curves, levels, etc...

At this point, I do an IMAGE/RESIZE... I'm actually doing a bicubic resample down to 640 pixels on the long side. After this is done, I use the sharpen filter if necessary and then save my file.

When I save, I do NOT use the save for web function. I do a normal save to JPG file type and use the quality slider to adjust my file size before the save takes place....

This seems to work great.. I have never noticed any image problems due to the save...
08/07/2002 12:13:37 AM · #17
JM:

thanks. this probably falls under the "there is more than one way to skin a cat" category.

I have saved your comments along with the prior method. I'm going to try them both.

Bart
08/07/2002 01:30:45 AM · #18
I always save my "final size" image in TIFF format as an intermediate step, after making tone adjustments and such. I can then apply the Unsharp Mask as the last step, and use "Save a Copy" to save in JPEG. That way I can re-save with gradually lower JPEG settings until I get under 150k (I'm avoiding the "Save For Web" with it's size slider for now). I can also revert the TIFF file if I want to revise the sharpening.

Two notes on using Unsharp Mask. It heightens the contrast where different colors meet (how different they have to be is controlled by the Threshhold setting), but cannot bring an out-of-focus image into focus. And it is often better to apply the filter twice with lower settings than once with higher settings.

A JPEG file will be/get bigger as it is sharpened since it provides more detail, and the efficiency of compression is dependent on how much detail is present.
08/07/2002 01:36:40 AM · #19
Thanks everyone! This really helps a lot. I will print this out and then practice, practice, practice...

Bye the way... Photo Shop LE came with my camera, but what is the best way to know what everything does? Sometimes I get the feeling that everyone "just knows", except me, as if it were a genetic thing that I somehow missed. Is there a tutorial out there somewhere or did everyone learn by reading the "Read Me" that nobody ever reads???
08/07/2002 02:27:56 AM · #20
First lets get one thing strait: I don''t have Photoshop. I use a combination of ImagePals Image Editor, Ability Photopaint(wannabe Photoshop), Ixla Photo Easy, Poloroid Photomax SE, Camedia Master (came with camera) Zonerdraw 3, and yes, Windows Paint. Those are just the ones that are legal. My other imaging programs are Greetings Workshop, Colordesk, RAD video Tools (Also does imaging), Morph Editor, Ulead Cool 360, Kia''s Power Goo (fun program), Corel Presentations 10 (Awesome program) and Powerpoint 2000. I''m set for life (And a little bit afterwards!)

I know a lot about digital imaging but not much about digital photography. I was going to say something that had to do with this thread, but I spent so much time writing the first paragraph that forgot what I was going to say. I''m only sixteen and I already have the memory of a sixty-one yaer old!

* This message has been edited by the author on 8/7/2002 2:32:11 AM.
08/07/2002 01:13:11 PM · #21
Everybody gave you good advice. One thing I want to question, do you have an optimizer with your software? With my Paint Shop Pro 7 I get the file size at what is required for the contest then I lower it to under 150k with the optimizer and I don't notice that much difference in the image. If you or anyone is interested you can download Paint Shop Pro 7 for 30 days to see if you like for free? //www.jasc.com/
Yes, sharpening an image raises the size but I would not think it should double the size? Raw to Tiff is what a lot of the pro's use. I find it too time consuming for a hobbyist like myself. What I do is take an original large JPG and write it to a CD before I do anything? Then I edit and do two copies of that on other CD's. You lose some compression doing it this way. Is it worth it for every photo to do Raw or Tiff?
08/07/2002 01:29:43 PM · #22
Originally posted by jmsetzler:
When I save, I do NOT use the save for web function. I do a normal save to JPG file type and use the quality slider to adjust my file size before the save takes place....

How come you don't use the save for web function, John?
08/07/2002 01:31:14 PM · #23
Originally posted by Kimbly:
Originally posted by jmsetzler:
[i]When I save, I do NOT use the save for web function. I do a normal save to JPG file type and use the quality slider to adjust my file size before the save takes place....


How come you don't use the save for web function, John?
[/i]


I don't know how to explain it technically, but it seems to flatten out my colors. When I get home, I will play with it some and see if I can generate an example with each save function to describe why I don't use it...

08/07/2002 01:36:27 PM · #24
Originally posted by bobgaither:
Everybody gave you good advice. One thing I want to question, do you have an optimizer with your software? With my Paint Shop Pro 7 I get the file size at what is required for the contest then I lower it to under 150k with the optimizer and I don't notice that much difference in the image. If you or anyone is interested you can download Paint Shop Pro 7 for 30 days to see if you like for free? //www.jasc.com/
Yes, sharpening an image raises the size but I would not think it should double the size? Raw to Tiff is what a lot of the pro's use. I find it too time consuming for a hobbyist like myself. What I do is take an original large JPG and write it to a CD before I do anything? Then I edit and do two copies of that on other CD's. You lose some compression doing it this way. Is it worth it for every photo to do Raw or Tiff?


RAW to Tiff yeilds the best image quality for sure, but you'd think that when your final file size is gonna be 640x480 the fine jpeg modes would work just as well. SUCKER, I have tried shooting in the fine jpeg mode for this challenge and regret it. I really wish I stuck with RAW. But thats just me.
08/07/2002 01:41:40 PM · #25
Bob, I'm a psp-er too. I learned that one key to a successful picture is to never edit the original jpeg image (especially if you don't have the raw option.) I either convert a copy to psp format as a first step or I use Irfanview to convert to tift.

I think the Potoshop people do have optimizers, it just not called that. Several have mentioned using the Quality slider. aelith
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