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animal
09-29-2000, 05:23 PM
i was wondering how to paint realistic water
for wildlife paintings

thanks animal

CarlyHardy
09-30-2000, 01:42 PM
How to paint water....realistically...

I don't try to paint realistically so I can't answer that one with detail. However, I can suggest a good book that I use for reference a lot...How to Paint Water by Patricia Seligman.

Also, check out the art lessons here at wet canvas which will give you some ideas about painting water too. Since acrylics can be used in many different ways...alla prima, glazing in layers of color...etc..etc..your method might vary, but the principles would be the same.

Have you posted any of your work here at wetcanvas?
carly

animal
09-30-2000, 03:10 PM
Thanks fo your advice. I have tried to post on wetcanvas, but the image is too big and too hard to see when it is too big, how do I make my pictures smaller so they can fit, and so they are not hard to see?

CarlyHardy
10-01-2000, 10:06 PM
If you scan your images, the scanner should have come with some software that would allow you to change the size of the file after it is scanned. If you take digital pics, you need to use a program that you can manipulate the image with size, light/darken, contrast...etc. I use Adobe Photo Deluxe which is similar to Photoshop but much less expensive. PaintShop is another program...and there are many more. Just be sure when scanning to set the ppi to 72...not 300 which is for printing purposes.

Failing all else, send me the image and I will downsize it for you and send it back so you can upload it to the critique center.
carly
e-mail [email protected]

jbitzel
09-28-2004, 03:08 PM
I think water is like painting glass, you just have to paint what you see and forget that it is water. :wave:

Charlie's Mum
09-28-2004, 04:19 PM
I'll refer you to the work of Marty C here on WC! - one of your fellow guides, and who posts here and in the Marine Art forum - his water is good!

http://www.wetcanvas.com/forums/showthread.php?t=218756

Hope his work helps you! :)

Richard Saylor
09-28-2004, 04:23 PM
Just be sure when scanning to set the ppi to 72...not 300 which is for printing purposes.
Unless you are printing the image, it makes absolutely no difference whatsoever whether the ppi is set to 72, 300, or 100,000,000, as long as all the other image parameters remain the same.

These two images have the same pixel size and file size, but the ppi of one is 300, and the other is 72. There are no differences in the images unless you try to print them, then the 300ppi print would be much smaller than the 72ppi.

http://pw2.netcom.com/~rlsaylor/300a.jpg
http://pw2.netcom.com/~rlsaylor/72a.jpg

Charlie's Mum
09-28-2004, 04:50 PM
Unless you are printing the image, it makes absolutely no difference whatsoever whether the ppi is set to 72, 300, or 100,000,000, as long as all the other image parameters remain the same.

Each attached image is 200 x 150 pixels and file size about 7 KB. One of them is 72 ppi, the other is 300 ppi. There's no difference in them unless you try to print them, then one print would be 1.8 inches wide, the other 0.7 inches

Thanks for this interesting note Richard - it will save me altering everything to 72ppi each time! I'm sure I read somewhere in the help here that images had to be 72 for the web, but you've just disproved that theory! :D

romell
09-28-2004, 05:53 PM
:D This thread was started by animal 4 years ago (Sept. 29, 2000) :D
Now probably he is a professional painter and figured out how to paint water realistically. :D

Einion
09-28-2004, 08:47 PM
Thanks for this interesting note Richard - it will save me altering everything to 72ppi each time! I'm sure I read somewhere in the help here that images had to be 72 for the web, but you've just disproved that theory! :D
Hiya, that's actually correct. Basically you have to consider the resolution and the actual dimensions. For whatever final size you want the image the resolution for the web should be 72ppi ideally.


:D This thread was started by animal 4 years ago (Sept. 29, 2000) :D
Yes, I was wondering how it got restarted myself! James? :)

Einion

Richard Saylor
09-28-2004, 09:12 PM
Hiya, that's actually correct. Basically you have to consider the resolution and the actual dimensions. For whatever final size you want the image the resolution for the web should be 72ppi ideally.
Why? The ppi is not the resolution of the image in your computer or on your monitor; it refers only to a hard copy print. A 640x480 image looks the same on the web and has the same file size regardless of it's ppi. Inches, after all, are not computer units, they are printer units. ppi is the nominal number of pixels an ink jet (or other) printer will use for each linear inch of a print. It is no more or less than that. If you take an image and change only its ppi, nothing happens. (Listen carefully, not even the slightest burp from the hard drive.) No resampling, nothing. It merely tags the image with a different resolution for a (hard copy) print. Changing only the ppi will change only the size of the print. An 800x600 image at 72ppi will produce a print which is 800/72=11in wide and 600/72=8.3in high. At 300ppi the print will be 800/300=2.7in wide and 600/300=2in high.

Of course you can specify the true resolution of an image by specifying both a ppi number and the dimensions in inches, but why go to all the trouble to specify the pixel dimensions indirectly like that? That's like someone asking me how far it is from Winston-Salem to Greensboro, and instead of answering 30 miles (or however far it is), I say "If you drive at 60 miles per hour you will get there in 30 minutes."

jbitzel
09-29-2004, 07:46 AM
As a photographer when talking to people this is the easiest, most misunderstood and hardest to explain concept. It doesn't really matter what the actual dpi is the browser will display this pixel count by this pixel count. Thats why when you view a 5x7 at 300dpi on the internet it wont fit on your screen without scrolling. However, 72dpi is the standard web developers size. I have heard rumors that this number was derived from the fact that the human eye can only see 72dpi, and that the only reason to have it any higher is if you might want to enlarge it. But, once again Saylor is completely correct for internet purposes the only thing that matters is pixel count. I am sure they stick with 72 because if you download and print a photo you dont want a 2in image. :wave:

Richard Saylor
09-29-2004, 09:23 AM
Thanks for backing me up, James. :)

Einion
09-29-2004, 10:51 AM
There are two reasons to prefer dealing with one's images in this way. First, it's faster for a browser to display an image in 'native' resolution; the difference tends to be marginal now but it used to be significant. The second and most important is that it's a good discipline for the person creating the image so they get used to scaling things correctly for on-screen viewing. I do this for a living and have taught it periodically for nearly a decade, so believe me when I tell you how easy it is for people to screw up if they don't get taught to do this in the right way :)

The ppi is not the resolution of the image in your computer or on your monitor; it refers only to a hard copy print.
Not quite Richard, ppi refers correctly only to digital images in memory, it's not appropriately used to describe output no matter how many times you might have read it. Output resolution is dpi or lpi only, it should never be expressed as ppi.

Inches, after all, are not computer units, they are printer units. ppi is the nominal number of pixels an ink jet (or other) printer will use for each linear inch of a print.
As you know, inkjet prints don't print in pixels, they print in dots reproducing the pixels of the image. If the pixels are small enough you get images where the output resolution controls quality, if they're larger you get reproduction of their shape - visible pixelation.

Listen carefully, not even the slightest burp from the hard drive.
Ah Richard, nice try but this operation occurs in RAM. Try doing this change and then closing the image and see if the software agrees that nothing happened :D

If you take an image and change only its ppi, nothing happens.
I know exactly what you mean here but it's very misleading to people unfamiliar with digital images or the software to say it in this way - Resample Image being on or off.


It doesn't really matter what the actual dpi is the browser will display this pixel count by this pixel count... But, once again Saylor is completely correct for internet purposes the only thing that matters is pixel count.
See my first point above.

I have heard rumors that this number was derived from the fact that the human eye can only see 72dpi...
Well so much for rumours! ;) There are high-resolution monitors today and when you see the difference between a standard display and one of them you'll see why HDTV is so much better than a normal television. It's the refresh rate of human eyesight that is tailored to in displays as that is relatively fixed, visual acuity is not.

BTW James there was nothing arbitrary about web developers choosing 72ppi - it was the basic resolution of monitors for years.

Einion

Richard Saylor
09-29-2004, 02:14 PM
Not quite Richard, ppi refers correctly only to digital images in memory, it's not appropriately used to describe output no matter how many times you might have read it. Output resolution is dpi or lpi only, it should never be expressed as ppi.
dpi is printer output resolution. ppi is appropriate for computer output or printer input. (Nowadays the printer itself may do some resampling and change the ppi.) Dots refer nominally to dots of ink. There is not a one-to-one correspondence between dots and pixels. dpi and ppi are physically independent quantities, although, to add further to the confusion, dpi is traditionally used to refer to pixels per inch.
Try doing this change and then closing the image and see if the software agrees that nothing happened.
Okay, you're right. :angel: Nothing happens to the resolution of the image, which requires resampling or resizing, by no means an instantaneous process on my machine. An 800x600 image remains 800x600. (I fervently hope that Photoshop does not resample on the sly.)
BTW James there was nothing arbitrary about web developers choosing 72ppi - it was the basic resolution of monitors for years.
Therefore 72ppi is no longer relevant. My screen is about 12" wide with resolution 1024x768, so its ppi is about 85. An image which is 5" wide at 72ppi would be only 4.2" wide on my monitor. (That's not fair. ;)) Thus expressing image resolution by using ppi and dimensions (in inches) is misleading. Far better to use only pixel dimensions for the web.

Charlie's Mum
09-29-2004, 02:56 PM
I'm opting out of this!!!!!!!! It's far too technical for my brain so I'll just stick with what 'The-Powers-That-Be' decree and do 72 res.!!!!!!! :angel:

Incidentally, when I resize an image in PSP8 and put in 72 res first, the dimensions reduce (for printing), if I were to leave those in the changed manner instead of increasing to, say 500pix, would my uploaded image be too small?

This thread was started by animal 4 years ago (Sept. 29, 2000)
Now probably he is a professional painter and figured out how to paint water realistically.

Duh! I though the request was strange, knowing Animal was/is a guide and project leader!!!!!!!! You see how our eyes often see only what they wish to see? e.g. the first part of the date and not the year also? :o :eek:

jbitzel
09-29-2004, 03:37 PM
Well so much for rumours! ;) There are high-resolution monitors today and when you see the difference between a standard display and one of them you'll see why HDTV is so much better than a normal television. It's the refresh rate of human eyesight that is tailored to in displays as that is relatively fixed, visual acuity is not.
Einion

Hold on one doggone second, you gotta be kidding me. HDTV? HDTV is horrible compared to a monitor. In fact regular cable is only 500 lines of resolution and HDTV is about 1200 I believe, so in reality my 54" hdtv can display 30 ppi. :wave:

Richard Saylor
09-29-2004, 04:13 PM
Incidentally, when I resize an image in PSP8 and put in 72 res first, the dimensions reduce (for printing), if I were to leave those in the changed manner instead of increasing to, say 500pix, would my uploaded image be too small?
The printing dimensions change merely because you are changing the inches-to-pixels conversion factor (ppi). It's just a maths thing:

width(pixels) = ppi x width(inches)

height(pixels) = ppi x height(inches)

The image size (uploaded or not) in a browser window depends only on the pixel dimensions, not the ppi or the printing size. Viewing the image full size (1:1) in PSP will give a good idea of what to expect. I think the image is just slightly larger in IE than in PSP.

Einion
09-29-2004, 04:44 PM
dpi is printer output resolution.... Dots refer nominally to dots of ink. There is not a one-to-one correspondence between dots and pixels. dpi and ppi are physically independent quantities...
That's what I said. You said ppi referred to the hard copy, which it doesn't, and I was just trying to clarify the issue. When I referred to output I meant the actual print, film or bromide paper.

...although, to add further to the confusion, dpi is traditionally used to refer to pixels per inch.
Not when taught correctly. There are plenty of sloppily-written guides out there that might make this mistake but a mistake it is! :)

I fervently hope that Photoshop does not resample on the sly.
Don't worry, it doesn't. It does do things one is not aware of (and wish it didn't) but this is not one of them :D

You are correct that pixel dimensions are all that is important in some case - maximum size for an image upload here for example but for the browsers the res should still be 72ppi ideally. For web design you often don't work purely in pixel sizes, especially today with WYSIWYG software where you can lay out the page in inches or centimetres, hence one needs to understand why an image should be a given physical dimension at 72ppi.


Hold on one doggone second, you gotta be kidding me. HDTV? HDTV is horrible compared to a monitor. In fact regular cable is only 500 lines of resolution and HDTV is about 1200 I believe...
James, if you check you'll see I said HDTV compared to normal television, as a parallel to high-resolution monitors v. normal displays.


I'm opting out of this!!!!!!!! It's far too technical for my brain so I'll just stick with what 'The-Powers-That-Be' decree and do 72 res.!!!!!!! :angel:
This can be a confusing topic, not to worry. Believe me, I've dealt with people who couldn't get their head around it no matter how often you explained it to them. :)

Einion

Richard Saylor
09-29-2004, 05:14 PM
You are correct that pixel dimensions are all that is important in some case - maximum size for an image upload here for example but for the browsers the res should still be 72ppi ideally.

I'm not convinced.

For web design you often don't work purely in pixel sizes, especially today with WYSIWYG software where you can lay out the page in inches or centimetres, hence one needs to understand why an image should be a given physical dimension at 72ppi.

A pox on WYSIWYG editors! :mad: :mad: :mad: I write my web pages directly in HTML and in such a way that they adjust to any monitor resolution. Depending on absolute linear dimensions (like inches or centimeters) may be what causes those hideous web pages which don't quite fit the browser window, necessitating horizontal scroll. Also, the code tends to be nasty, messy, and full of errors, which slows down loading for those poor souls (such as I) who are still stuck with a phone modem. In the hands of someone who understands how it works, I suppose a WYSIWYG editor could be handy for speeding up the writing of web pages, but in the hands of those less knowledgeable it can be a disaster waiting to happen.

Richard Saylor
09-29-2004, 06:00 PM
.....for the browsers the res should still be 72ppi ideally.

Ulead SmartSaver Pro, a tool for optimizing JPEG compression for web images, always makes them 96ppi.

jbitzel
09-29-2004, 07:21 PM
For web design you often don't work purely in pixel sizes, especially today with WYSIWYG software where you can lay out the page in inches or centimetres, hence one needs to understand why an image should be a given physical dimension at 72ppi.

Einion

I beg to differ, exactly what wysiwyg are you using, I know that both Dreamweaver and Front Page use pixel size when dealing with photos :wave:

Richard Saylor
09-29-2004, 09:53 PM
Okay, I took a JPEG (one of my photographs FWIW), saved one copy at 72ppi and another copy at 2540ppi. Nothing else was changed. They have the same pixel dimensions and file sizes. Here they are, side by side, on a rudimentary web page. Feel free to download them and analyze them in a photo editing program.

http://pw2.netcom.com/~tarper/ppi/ppi.html

Now will someone please tell me how 72ppi is optimal for a web browser?

Richard
Photos by Saylor (http://pw2.netcom.com/~rlsaylor/m6.htm)

Einion
09-30-2004, 12:25 PM
Now now gents, remember I didn't come up with 72ppi as a standard, don't shoot the messenger :)

Ulead SmartSaver Pro, a tool for optimizing JPEG compression for web images, always makes them 96ppi.
Hehe, well that's its problem. 96ppi is the 'standard' higher resolution of monitors.

I'm not convinced.
That's your prerogative :D

A pox on... hideous web pages which don't quite fit the browser window, necessitating horizontal scroll. Also, the code tends to be nasty, messy, and full of errors...
LOL, agreed!


I beg to differ, exactly what wysiwyg are you using, I know that both Dreamweaver and Front Page use pixel size when dealing with photos :wave:
Xpress and Illustrator to name two :wave:

Einion

Bobbo
09-30-2004, 12:44 PM
anyway :D

QUOTE candienjames
I think water is like painting glass, you just have to paint what you see and forget that it is water. :wave:

i think this is the right idea,
paint water like everything else,just the right color notes,forget it is water!

Richard Saylor
09-30-2004, 02:03 PM
If the ppi of an image makes a difference to a web browser, then surely one should be able to notice some difference between 1ppi and 72ppi, but there is none. Everything I've been able to find out about it on the web is either a rule without a reason or else totally obvious misinformation. Here's my final piece of evidence. It's a small color photo of a church, saved at 1, 72, and 2540 ppi. I think we can consider this superstition about 72ppi to have been abolished.

http://pw2.netcom.com/~tarper/ppi/ppi_2.html

LarrySeiler
09-30-2004, 02:47 PM
for extra info to those interested...I have an old thread in my Industry partner forum on making water, and several demos...

Larry

jbitzel
10-01-2004, 11:41 AM
Xpress and Illustrator to name two :wave:

Einion

I assume you are talking about Quark Express and Adobe Illustrator? Give me a break, how many have either used or even heard of those? Everybody knows that the majority of webpages are designed in Dreamweaver, frontpage, golive and Photoshop. :clap: :wave: