Posting photos

[zenpi314]

Hi All,

I am somewhat at a loss about the size of posted pictures.

I see people getting scolded for images that are too large, so I wanted to be real careful. I posted images that were definately 600 pixels wide and less than 150kb (by using photoshop), but when they are they posted, their wide depends on the resolution of the person's screen watching it, it seems. When I posted them at home they were less than 600 pixels wide after playing with the percentage of the html tag, but when I watch it at work, with a higher resolution monitor, it is over 800 pixels wide. hmmm.

Can anyone help me out. I'm refering to the images on http://www.fieldlines.com/story/2007/5/6/22758/92474

Thanks,

Arno

[kurt]

those photos are fine first one was like 455 x 600 and 88K well within the rules second one was close to the max on file size at 149k mite wanna consider reducing picture quality when you resave the pictures after sizing to 50% or so that realy cuts the file size.

[Capt Slog]

Thanks Kurt.

The 'quality' bit is something that I forget too.  

It really depends on the software that you are using to play with your pics, mine (olympus) lets me resize but makes no mention that I've noticed of the quality when I save the resized image.  This has often confused me in the past because a pic of half the orginal size will not have half the file size.

[kurt]

if your photo editing software does not let you adjust the picture quality then you need better software because that is very important part of getting pictures under the size limit here mite i suggest irfanview or photofiltre for software they are both free and work well.

[RogerAS]

zenpi314,

In Photoshop, before starting to save anything, look at image size and view in pixel dimensions. Adjust accordingly. When the image is within size specs and you're ready to save pull down the "save for web" option from the FILE menu. A new save dialog window will open and present you with options.   Select either JPEG or GIF. Within these options one can determine the final file size in kilobytes and quality, which are related. In JPEG mode the quality sliding selector will determine the file size and in GIF mode the number of colors allowed is the limiting factor. Photoshop will display the file size in the lower left corner.

Hope this helps,

[zenpi314]

Hi RogerAS,

Thank you for the information.

My problem is not to get the images the right size and quality, but that this forum will resize the images depending on the resolution of the screen being used to view the image. For example, if I look at the image of my prop (follow link on top of thread) on a low resolution monitor (1024x786), it is 510 pixels wide, but at high resolution monitor (1680 something) it suddenly is 828 pixels wide.

I just found out that it happens because the image is being displayed as a percentage of the screenwidth. Even on the same screen, if you open your favorite, effectively making your screen smaller, the image will shrink. That is why most of the images on this site look somewhat distorted (not very sharp and straight lined). When you insert an image, the accompanying html will default the image size to 80% of the available screenwidth. Now I just need to figure out how to modify this html code, I guess.

I'll get back when I figure it out.

By the way, please correct me if I'm totally wrong here. I can handle it, I'm a big boy.

Thanks again for all the help.

Arno

[kurt]

the defalt html the picture inserter uses sets the size to 80% of actual piture width so if the picture is 640 wide then it dispays as 80% of that. some brousers automaticly resize pictures up or down to fit the screen size and that is what you may be noticing. please do not remove the width=80% tag from the html when posting pics unless your picture is vary small like 450 pixels wide. thanks.

[zenpi314]

Hi Kurt,

Thanks for clarifying. I noticed that the 80% was that of the image's true width, but could not figure out why it changed from monitor to monitor. Now I know, thanks.

Arno

[winston]

Can we post from photobucket or similar sites--that would save your bandwidth I think

[alancorey]

I don't mean to argue, but that's not quite correct.  The percentage refers to the size of the space the image is fitting into, not the original size of the image.  Scoop does this to make sure all the images will fit into the space available without stretching out the column width.

I made a little demonstration page at http://www.otherpower.com/images/scimages/6871/imgwidth.html which attempts to show that the 80% refers to the page width or column width.

I like Scoop and I think it does a good job.  It's a lot faster than anything I've seen written in PHP, and I've seen several posts saying the board should be using some PHP program.

If file size or bandwidth gets to be a real concern, it might be fairly easy to deal with it.  I don't know if Scoop stores its images inside the MySql database or if they exist outside in the file system.  If they're outside, one could just write something that climbs the directory tree and looks for images over a certain width or height.  One nice thing about the JPEG format is that it's possible to open an image at full size, 1/2 size, 1/4 or 1/8.  That makes this one-line script possible:

djpeg -scale 1/2 infile.jpg | cjpeg -optimize > outfile.jpg

This will create a half-size copy of infile.jpg.  djpeg and cjpeg are included in the JPEG library, and that's pretty common on at least OpenBSD and FreeBSD machines, probably Linux as well.  Try "man djpeg" to see if you've got it.  So you write something that climbs around the directory tree looking for images that are too big, then when it finds one it creates a backup somewhere and resizes it.  This is probably not a nice thing to do to drawings like schematics, but they shouldn't be in jpeg format anyway.  

Maybe later versions of Scoop will address this, this can't be the only board having these problems.  I haven't poked around their site looking for answers, but I did install a copy on my laptop (OpenBSD) to play with.  I don't have any content since I'm the only user, and I prefer PostgreSQL to MySql, so it isn't totally configured yet.

It's easy enough for any user to upload a smaller replacement for any image that's too big, but this places the burden of chewing them out on the editor/moderator.  That's not right.  Irfanview (Windows), The Gimp (Unix/Windows) and ImageMagick (Unix) are all free programs that work well for resizing images.  Photoshop is excellent but very expensive, Photohop LE is adequate and comes bundled with various things, Paint Shop Pro is adequate but shareware.  Learn to use them.  Crop as well as just resizing.  A previous post of mine on the subject: http://www.fieldlines.com/story/2007/1/19/232914/030

  Alan

[zenpi314]

Hi Alan, Thank you very much for taking the time to explain this.

I see that it is not the first time you had to do this. Sorry.

It does solve my problem though. I don't like the look of my images being stretch different ways, so for me (because I know that the image width is 600 pixels [photoshop]) I will just take out the html part that resizes it to 80% of the available space. I don't mean to incourage this practice because I realize that quite often large images are being posted, which mess up the thread width. Hopefully it is allowed to do that. I will make sure that the images do not exceed 600 pixels (and 100k)

Thanks again.

Arno

[kurt]

your not listening i told you if you were going to remove the width=80% tag resize to 450 pixels wide or so not 600 pixels and for winston you can host your pictures at photo hosting sites but they still need to be under 150k so that dialup users can download them easly. otherwise they cannot be displayed here and will be removed.

[TomW]

What Kurt said....

[zenpi314]

Hi Kurt and TomW,

I don't mean to be disrespectful, but I'm not quite getting it.

The 80% in the html tag resizes any image to 80% of the available space (as I believe was explained by Alan), but when you take it out, it displays the image at the resolution of the actual image. If that image does not exceed 600 pixels (and 100k), is that not all that matters? Sorry, if I'm too hard of hearing (reading).

On my high resolution screen at work, one of the images I posted with the 80%tag had grown to over 800 pixels, even though the original was 600.

Arno

[kurt]

some people run there monitors at low resolution like at a resolution of 800 x 600 if you post a picture that is 600 pixels wide without the width=80% tag you will cause them to scroll sideways to read the thread. mite not effect you if you are running high resolution but it will effect others so be nice to others and do it like i say or leave the width=80% there.

[zenpi314]

Understood.

Thank you for your help.

Arno