Bird
Epic Contributor
I'm running Windows 98, Second Edition, so my MSPaint doesn't offer the JPEG option either.
Bird
Bird
Little help please
- Thread starter kubmech
- Start date
Harv
Elite Member
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Okay, Muhammad -- I agree and disagree with you on this one. /w3tcompact/icons/smile.gif
Although I used Photoshop to set the dpi to 400, the raw .gif file format does not maintain that information. I thought it did, but it turns out the "resolution" field in .gif files refers to the bits per pixel, which to me is the color depth. Photoshop apparently stashes the dpi information somewhere other then the data portion of the file, because it remembers it when you re-open that file. Oh well.
.jpg files, however, do have a resolution field which does refer to the dpi. This information is available to any software reading the file, if it needs or chooses to, but browsers, as far as I know, ignore it. Unless otherwise specified in the HTML, they will simply interpret the image size by its overall dimensions, using whatever "resolution" is native to the display device.
I tend to scan stuff at high resolution (simple setting in my scanning software) and then monkey it down to whatever suits me later. That's just me.
So, although I agree with all your resolution math, I still think it's probably safest and most predictable to pick an image size, in pixels, for your final output.
I've attached a .jpg version of my doodle file, Muhammad. When I download it back from the server, Photoshop still knows the resolution is 400 dpi. If I'm putting 2 plus 2 together and coming up with 5, I would appreciate any clarification you can provide. /w3tcompact/icons/wink.gif
Although I used Photoshop to set the dpi to 400, the raw .gif file format does not maintain that information. I thought it did, but it turns out the "resolution" field in .gif files refers to the bits per pixel, which to me is the color depth. Photoshop apparently stashes the dpi information somewhere other then the data portion of the file, because it remembers it when you re-open that file. Oh well.
.jpg files, however, do have a resolution field which does refer to the dpi. This information is available to any software reading the file, if it needs or chooses to, but browsers, as far as I know, ignore it. Unless otherwise specified in the HTML, they will simply interpret the image size by its overall dimensions, using whatever "resolution" is native to the display device.
I tend to scan stuff at high resolution (simple setting in my scanning software) and then monkey it down to whatever suits me later. That's just me.
So, although I agree with all your resolution math, I still think it's probably safest and most predictable to pick an image size, in pixels, for your final output.
I've attached a .jpg version of my doodle file, Muhammad. When I download it back from the server, Photoshop still knows the resolution is 400 dpi. If I'm putting 2 plus 2 together and coming up with 5, I would appreciate any clarification you can provide. /w3tcompact/icons/wink.gif
Attachments
Harv,
Right. We can probably keep saying similar things back and forth, and wind up with the same conclusions. I think we kind of went into this another time, also. /w3tcompact/icons/wink.gif
Right. We can probably keep saying similar things back and forth, and wind up with the same conclusions. I think we kind of went into this another time, also. /w3tcompact/icons/wink.gif
Harv
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Muhammad -
Deep down, I think we're actually in violent agreement about the whole thing, just coming at it from different perspectives.
Kubmech originally asked for a "little help". I think I've provided about as little as anyone. /w3tcompact/icons/crazy.gif
Deep down, I think we're actually in violent agreement about the whole thing, just coming at it from different perspectives.
Kubmech originally asked for a "little help". I think I've provided about as little as anyone. /w3tcompact/icons/crazy.gif
Harv,
I know this "slugfest" is really between you & Muhammad, but I'm butting in anyway /w3tcompact/icons/smile.gif.
I saved both of the files, as jpg and gif. In Photoshop, the GIF image "print size resolution" is 72 ppi. The jpg image "print size resolution" is 400 ppi. They are both identical in viewed image size, at 720 X 900 pixels.
The naked eye can discern considerable difference in these two images. With the jpg image the text is heavier and darker and the machinery portion retains more detail. It is obvious that the Gif image does not have the same amount of "image info" as the jpg image.
Now, the final saved image size of these images is different too. The gif is 24K and the jpg is 49K. If I reduce the print resolution of the jpg down to 72 ppi to match the gif, the final saved file size is only 7K for the jpg. The viewed image quality is degraded from the 400 ppi, as one would expect.
I think what you and Muhamad (and I) are discussing is a very different matter from the cause of the problem of TBN forum users in having gigantic image file sizes.
They should make their original scans at 4 or 5 inches wide, since that is as large as is usually practical for the forum. They should also adjust the image print size downward to around 72 dpi, since many programs will have it much higher by default. What they wind up with is a "millions of colors" image at 8 x 12 inches and 400 dpi print resolution. THAT is always going to be a huge file.
Maybe you & Muhammad could put together a "quickie" FAQ on scanning for the forum...??
BTW Harv, think you produce some of the very best quality of images for the forum. Not to mention your pioneering work on graphic sig files. Keep up the good work!
BobT.
A Indiana Boy
I know this "slugfest" is really between you & Muhammad, but I'm butting in anyway /w3tcompact/icons/smile.gif.
I saved both of the files, as jpg and gif. In Photoshop, the GIF image "print size resolution" is 72 ppi. The jpg image "print size resolution" is 400 ppi. They are both identical in viewed image size, at 720 X 900 pixels.
The naked eye can discern considerable difference in these two images. With the jpg image the text is heavier and darker and the machinery portion retains more detail. It is obvious that the Gif image does not have the same amount of "image info" as the jpg image.
Now, the final saved image size of these images is different too. The gif is 24K and the jpg is 49K. If I reduce the print resolution of the jpg down to 72 ppi to match the gif, the final saved file size is only 7K for the jpg. The viewed image quality is degraded from the 400 ppi, as one would expect.
I think what you and Muhamad (and I) are discussing is a very different matter from the cause of the problem of TBN forum users in having gigantic image file sizes.
They should make their original scans at 4 or 5 inches wide, since that is as large as is usually practical for the forum. They should also adjust the image print size downward to around 72 dpi, since many programs will have it much higher by default. What they wind up with is a "millions of colors" image at 8 x 12 inches and 400 dpi print resolution. THAT is always going to be a huge file.
Maybe you & Muhammad could put together a "quickie" FAQ on scanning for the forum...??
BTW Harv, think you produce some of the very best quality of images for the forum. Not to mention your pioneering work on graphic sig files. Keep up the good work!
BobT.
A Indiana Boy
Harv
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<font color=blue>I know this "slugfest" is really between you & Muhammad,</font color=blue>
YIKES! /w3tcompact/icons/shocked.gif I hope that's not what it looks like, Bob!
I thought we were just having an overly technicical discussion which Muhammad was wise enough to nip in the bud, seeing as how we've been there before. As near as I can tell, we are all (including you) in agreement on the techno-aspects of the thing, with perhaps a difference of opinion on the best way to approach the problem.
I have no problem whatsoever agreeing to disagree (that's what makes these forums interesting, isn't it?), I would probably recommend that the general populace pay the most attention to what Muhammad says. I think the only time I ever caught him making a mistake is when he once said he made a mistake. /w3tcompact/icons/laugh.gif
YIKES! /w3tcompact/icons/shocked.gif I hope that's not what it looks like, Bob!
I thought we were just having an overly technicical discussion which Muhammad was wise enough to nip in the bud, seeing as how we've been there before. As near as I can tell, we are all (including you) in agreement on the techno-aspects of the thing, with perhaps a difference of opinion on the best way to approach the problem.
I have no problem whatsoever agreeing to disagree (that's what makes these forums interesting, isn't it?), I would probably recommend that the general populace pay the most attention to what Muhammad says. I think the only time I ever caught him making a mistake is when he once said he made a mistake. /w3tcompact/icons/laugh.gif