[Fred Flick Stone]

Back from the dead. I am starting the replies on a new thread because there are just too many images on it, and I don't want the replies to get lost in the shuffle. So I will continue to keep this thread alive so long as there are cubes to grade...off we go, but just a few tonight, I need sleep badly...

Dines, your up first...for the obvious, none of these objects reside on the same ground plane. Drawing these objects from such an extreme angle the first time around is really tough, and quite taxing to try. With no valid horizon line, it is very difficult to establish the acurate ground plane, much like you have in this image. Shadows are pitch black, not right, and the cylinder and ground look grey, not white. I would stick with just cubes for this first part of the tutorial. Part two is going to cover round forms.
There is also no real controlled gradation of value on the cube. The reflective light on the cylinder and sphere are too contrived, they aren't harmonious to any real bounce light that might be happening in this scene. Try just cubes, and look at spooges first example to get an idea of the value balance of white objects on a white ground plane. And I strongly encourage this, I got too extreme and bought wood blocks and foam blocks, but get some white bristol board, and make some cubes with the board. Take the cubes outside, put the on a white sheet of paper 18 x 24 preferably, to allow for a good amount of proper bounce light. Then copy what you see. The results will shock you. Nothing what you thought they would be...keep trying, and great effort, every failed attempt hopefully leads to a successful recovery...


Alan-since you see the errors, I wont feel bad repeating them for everyone to see, so they might not repeat them. No established horizon line, grey surface instead of white. Light is directly behind the boxes, making the cast shadows really difficult to read properly. Next time, put the light off the the left or the right side...No value transition in the cast shadows
Gradations of reflective light on the cubes is incorrect. And there is barely any to no gradation of value on the light sides...And finally, the same thing I am repeatedly seeing-both cubes are drawn from different horizon lines...keep trying em, you'll get them, your not that far off now. Follow the same example I gave to dines up top...

Eetu-I really like your ghostly renderings on page two. Although I would venture to say that the shadows are all a bit on the dark side. But it gives a killer impression of film noir...
As for the drawn shapes, well they aren't solid in terms of rendering to really give any proper crit. All I could say is go back and solidify the shapes, and make less of a harsh transition between value breaks...


Ilmi-Not so heavy handed next time. Everything is so dark, there is no real value difference in yor cast shadows and your dark planes of the cubes. The cast shadows are incorrect in their volume. They look like they are being projected from a fish eye light. The forground shadows are way too distorted, and the background shadows are too small for the forground shadow sizes. The first cube would not be casting a corner shadow on the second cube the way you have them drawn, mainly because the first cube is the same height as the second cube. None of the cubes are square, or cube like in their construction, too many angled faces. ANd they all come from different horizon lines just slightly...

Look at the examples francis has posted on light, and try these guys again. Also try drawing the cubes facing different directions instead of all lining up parallel to each other...


Sumaleth-So far we have an A. Well, we don't have letter grades, but this is the closest thing to correct I have seen yet. Shadows are all coming from one light source, casts and cores all look pretty good. But, the refective lighting on the cube is incorrect. Since the ball is white, and not a dark value, where that ball is clser to the box will be the hottest values on the cube face. The upper left corner of the face would be darker instead of beginning the radiating of light value through the face. Also the bounce light on the dark side of the sphere looks too spot lit. You would actually have more hot light under the sphere, this is where the ground plane bounces back up with its reflectivity to the ball. The top portion of this side of the sphere would be darker since it is taking on refraction from our atmosphere. Same with the dark side of the cone. This one is tricky since it is all pitched upward in slope. But it would be warmer near the base, and darker as you climb toward the point of the cone. Less surface area to catch the bounce light...
The value banding on the light side of the cube, not the top, needs more value separation between the side and the ground plane. Oops, the top of the cube does to. I just looked at it and realized I might have been misleading you...Great attempt overall, and thanks for helping out again...

Janne-First, instead of transitioning the groundplane from a dark grey to white, and making the sky white, keep the ground plane very light and put the dark value in the sky. As of now, it looks like the cubes are lit on a foggy day...The cast shadows are incorrect. Way to fanned out. The first cube would not be casting such a wide shadow. The shadows of the cubes are projected from different light sources, not the same one. The transitional values are incorrect in the shadows also.
The cubes are not cubes yet, and they need to be better faceted together, 2nd cube front corner...
Value transitions on the light sides are incorrect also. Looks like the cubes are absorbing bounce light from a dark surface...follow the example I gave Dines at the top of the page to better understand how light works on white cubes, sitting on a white surface...

Eetu-I will crit the spheres in the part two of the tutorial, where I will cover rounded surfaces with a better understanding of them...


sfr-I will get to you tomorrow, and as many others as I can. I am going home to sleep now...good night...

[dines]

Fred,
thank you very much for your help !

I'll read all your comments and try to work on my cubes

By the way, i wanted to thank you (one more time) for all the time you give to the forum threads,
it's really appreciated and nothing can make us happier than learning with such a great artist !

dines. http://www.nexen.net/koubis

[Sumaleth]

Thanks for the comments, Fred! Before I dig in for version 3.0 I have a few questions about the "why" of the changes;

>But, the refective lighting on the cube is
>incorrect. Since the ball is white, and not
>a dark value, where that ball is clser to
>the box will be the hottest values on the
>cube face. The upper left corner of the face
>would be darker instead of beginning the
>radiating of light value through the face.

The upper-left lightening on the cube was supposed to represent the accumulative reflective light from the environment (I have been working on the assumption that the entire environment is white, not just the ground plane).

The little splash of white at the top/right of the back of the cube was the reflective light from the top portion of the sphere also I see now that it should have been a brighter value than the lightest part of the reflective lighting in the other corner (as you explained).

The darker portion of the back of the cube was essentially a soft "core shadow" since the bottom portion of the front of the sphere is in shadow.

The shape of the core shadow was basically a guess - the amount of bright area on the sphere expands as we move around the sphere so the core shadow, which would otherwise have been more round, gets eaten away by the increasing reflective light.

>Also the bounce light on the dark side of
>the sphere looks too spot lit. You would
>actually have more hot light under the
>sphere, this is where the ground plane
>bounces back up with its reflectivity to the
>ball.

This I'm very lost on. It seems to me that, just as the sphere creates a core shadow "in" the cast shadow from the cube/sphere, the ground plane would likewise create a core shadow on the sphere.

Not having not heard of a "core shadow" prior to this tute I may misunderstand it's purpose but even on Craig's image there seems to be a core shadow created by the cast shadow on darkened faces. So I'm unsure where the reflective light would come from that would lighten the 'underside' of the sphere - very little light would reflect up from the ground since it's in deep shadow. This is why my reflected light on the back of the sphere seems more like a highlight than reflected light - the lightening is eaten away by the darkening on the surface underneath.

>The top portion of this side of the sphere
>would be darker since it is taking on refraction
>from our atmosphere.

As mentioned, I had been assuming an all-white environment which is why all my vertical surfaces slightly shade lighter upwards. Are they right based on that type of environment or should I still take away that vertical lightening?

>The value banding on the light side of the
>cube, not the top, needs more value separation
>between the side and the ground plane.

I actually ran a really soft lightening along the base of that side to give the feeling that the bright floor is reflecting light back up onto the side of the cube. Since the surface was quite light to start with it almost gets washed out with the additional reflected light from that close surface. Wrong thinking?

>Oops, the top of the cube does to.

I think the only way I could make the top of the cube separate more clearly from the background and still be "right" would be to darken the background a little behind the top of the cube?

--

Anyway, if you could explain why my thinking was wrong in the above cases I'd really appreciate it. I know I should make some white cubes up and see for myself but I'm lazy and that still wouldn't satisfactorily explain the "why" to me .

Thanks again,
Rowan.

[freddy flicks stones]

Sumaleth-I played hookie from my work for a moment and set up my shapes on a white board to look at your questions, so I can hopefully answer them logically without shooting in the dark...I did this exercise at 4:30 in the afternoon for the long shadows you have in your image...

You asked about everything in the reply, so what I will do is give you my feedback as to what I observed...

First let me ask you this, did you make this up from nothing? Do it in 3D, then enhance it in photoshop?

The results were asI said,nothing like you would imagine. My light was coming from left side slightly, from in front of the objects. I couldn't quite get your placement, as the volume of the round shapes didn't quite line up like yours. But, I will post my little quicksketches when I can scan them. I am at home right now, no scanner and peice of poop computer...The left side of every cast shadow, at the base of every object, was the brightest spot in all the shadow values. Almost too bright to the point that it looked like it was on the light side.This was the hottest point of contact on the ground for all the objects,interesting phenomena...The shadows got their darkest at the left side bottom of each of the casts. This is the furthest point down from the light source on each object, but this point on each object gets the most bounce light from the ground plane of all the places on each object. So the ground will be absorbing the least refraction from the object, if the object is taking on the most bounce fromthe ground...read that a few times, I swear it will make sense to you...
The ball had the most reflective light coming from the ground plane at the very bottom of the ball closest to the camera. The cast shadow is the darkest only just under the ball, not much spill over into the rest of the shadow. Then the core shadow was very diffused on the lower portion of the core because of the bounce light from the ground. The core shadow was the strongest at the top of the ball where there is more atmosphere making contact with the ball. The way I turned the cube is slightly different from your angle, so you can see the dimensionality of the cube. As I said, yours was a bit too washed out. But the side closest to us was the darkest. The side facing the cube was the second lightest, because of all the bounce light from the ball. There is actually a core of dark cutting a little diagonally through the middle of the plane, as there is bounce light hitting the upper left, and ground bounce light hitting from the bottom right.

Then the cone and cylinder were way more washed out in form than I ever thought because of all the glare coming from the ball and cube. The base of both objects' core were washed out and almost gone because of so much bounce light. It looks like the core moves to the middle of the dark side of the objects near the bottom of the shapes, because of the intense bounce light from the ball and cube. Then the core transitions around the form back to where it should reside. The top of each objects cast shadows were the only areas where the cast shadows were the softest. Probably the last third of the length of each shadow started to slightly diffuse. not too much though.

I really suggest getting objects and go outside and try this. It is such the eye opener. It taught me a great deal about the influence of everything surrounding the forms, and the forms influence on them. I am still off quite a bit with my drawings, but my knowledge of it will now haunt me in a good way forever... Cheers...

[This message has been edited by freddy flicks stones (edited June 04, 2000).]

[sydneyshan]

Thanks for the continued effort and dedication, Ron! I'm in the process of doing some more cubes at the moment. When they are finished, shall I post them to this thread or the main one?

Thanks again!

-sydneyshan
(Shannon Murdoch)

[sydneyshan]

Just wondering about this diagram below (or just in general), is the standard human viewing area always 90 degrees?




[This message has been edited by sydneyshan (edited June 05, 2000).]

[Sumaleth]

>First let me ask you this, did you make this
>up from nothing? Do it in 3D, then enhance
>it in photoshop?

It's totally done in photoshop. Here's the line construction;
http://users.bigpond.net.au/sumaleth/sumaconstlines1.jpg

The original image is x4 that size although I did all of the construction lines zoomed back at that distance (25%) which means they were a little inaccurate when I finally cropped the center out and saw it all close up. I worked out the rounded parts of the shadows in a little more detail once I was cropped in closer and then blocked the colors and shapes in very simply.

I'd post the PSD file except that it's 50meg and uses almost 400meg of memory to view!

A lot of people seem to be wondering how to get sharp edges and smooth shading and it's actually quite easy. Every distinct shape in my image has it's own layer and a mask. I would paint a really rough version of the shape onto the mask (eg. the cube back), then slice away at it with the lasso tool using the construction lines to determine where to slice.

Once thats all set up you can use massive airtbrushs (I used 100-200-300) with light swipes of the brush to get incredibly smooth shading, and since the mask is there you don't need to worry about spill.

--

But back to the task at hand, I'm going to do the changes as you've suggested although I still can't understand how some things work. I've just upgraded to LW6 so I'm going to try out radiosity on the two-cube version and see what it does .

I'd love to see some photos of your real cubes!

Cheers,
Rowan.

[dines]

For the image posts,

should we put them here ? or maybe on the other thread ? i just finish my cube

Durrenberger David (dines)
http://www.nexen.net/koubis


[This message has been edited by dines (edited June 05, 2000).]

[AliasMoze]

Fred, Sumaleth, anyone:

I just did some observation of two cubes in daylight. Wow, the values are much lighter than I've been painting them. I've noticed, of course, the same thing on the sides of buildings and what-not during the day.

Fred, I realize we should be trying to use the entire value range, but --for the sake of realism, should we try to do studies using the upper part?

------------------
AliasMoze
:) :) :) :)
"That activates my hilarity unit."

[Spiritwolf]

Maybe, but for the sake of simplicity wouldn't we be better off disregarding ambient lighting conditions? It makes it hard to judge the quality of shading and shadowing if we don't have a fixed ambient value. Since total darkness is a fixed value that we can all easily create I would assume this to be the ideal lighting conditions for this tutorial. I think he mentioned that the fall-off would not be so great if there was a secondary source of light such as the sun. Obviously we cannot all create the exact same atmospheric lighting conditions without being in the EXACT same area at the same time, But it is easy to create a dark room and use a flashlight which is probably the closest we can get.

Don't know if this is the right answer, but it is my answer!

-Spiritwolf

[dines]

Just moving the thread on top

[Affected]

On the other hand, the assignment WAS to use natural light...

------------------
Affected

Democracy is a lie

http://affected.xs.mw

[Spiritwolf]

hehe, was it?

Damn...well....*shrugs* I know for a fact that the shading would be much different depending on time of day and lighting conditions (overcast, sunny, etc.)....die cubes!

-Spiritwolf

[Gimbal]

I'm still working on my cubes but I figured I wouldn't post any until I thought I had it down to a decent degree or was stumped on how to fix something. That way I wasn't clogging up the thread with stuff I already knew needed more work. But I see this thread falling further behind and was wondering if I'm the only one who is still working on cubes.

[craig]

Gimbal-

I am still working on cubes.
I was going to wait to post more
until Fred came back to provide
critiques or lessons. I think he
is way, way, way busy right now....
I am going to work through
the critiques he has provided on
others and work from that.

craig

[Fred Flick Stone]

Hi. Been really friggin swamped. And the house thingy is still NO GOOD!!!

I will review some cubes to take my mind off the ulcer I am getting stressing out on the house thing...to the cubes...I am going to start off where I left off with the biggy post, and try to get caught up there first...SFR...ready to go?

sfr-you have the horizon line blues. Both those guys are on different horizon lines. Remember, when you turn a cube in world space, it recieves a new vanishing point, not horizon line. I would also drop the horizon line a bit so you can actually see one in the horizon...I think this will help you learn more about the horizon line and how it works.
Looks like your cubes are actually dice. They have very soft corners. They need to be firmed up a bit. Trying to figure out the casts of a rounded corner are not easy, and you are going to experience this nightmare very quickly if you don't tighten up those corners.
Cast shadows are clearly lit at different times of day, or by different lights. My really big suggestion would be to build two cubes with bristol board,or some sort of really durable WHITE board, put them outside, lit by the sun, and draw what you see. You really will be surprised at the results. I think all in all the values in the images are a little too dark. Nice blends of value on the light and medium sides of the cubes, but they are a bit too dark. Or the cubes look grey, not white. I like how the values are painted in though, not too airbrushy looking...


Leno, your image can't be accessed...

Anticz-second one in color won't be looked at, as color tends to create really strange bounce light values and hues, but as for the black and white...All the cast shadows on the ground are very flat. There should be some atmospheric blend in the farthest areas away from the object casting the shadows. Also, they are softening up way too much way too soon. But then again, the whole image is a little out of focus...
The reflective lighting on the cubes are not quite right. There would be more bounce light in the upper corners of the cube, as the lower area of the face will have no reflective light in it. It is too close to the surface that has no light projected onto it. But, the corner where the cast starts will have a bunch of light bouncing onto it because of it being so close to the light ground plane, bouncing white light into it's dark side.


I included a quick, ten minute observation, if I had to crit this, I'd give it a c- or D+. Very sloppy, very rough, but what I was trying to get at, since I have no real sit down time right now to do this, I was trying to show what happens to the sides, and shadows in the sun light. THings you never imagined would happen, go on all over in the shapes. But for anticz, see how the light affects the medium side of the cube, especially at the corner where the cast begins. The core shadow on both the ball and the cylinder are too consistent all the way from top to bottom with respect to the shapes. There would be,and is core diffusion as the object sits onto the ground plane. I tried to indicate it in the scan, but Anticz, come see me and I will show you the original drawing and comment on these points in more detail if you would like...

Alias Moze-I am not totally certain, but your cubes look to me like they are on different horizon lines. Just slightly. I am using the amount of volume on the top faces as a comparison. I figured it out. I had to stare at it a while. The cube on the right is not quite a cube. If you look at it carefully, top plane, the left far side is narrower than the closest top right edge. Like one side is one inch wide, the other side an inch and a quarter...
The values on the top and the side of the cube are way too similar. These two planes would be very differently lit. Tops nuch brighter,as they are catching most of the light. Get those cubes out and get them under the sun. THe value transitions everywhere in this image are too subtle. Again, the cubes in the sun will be the eye opener...

Boomstick-There is a lot here, I would go into it but I think by looking at the image yourself you can see the very obvious. Cubes aren't cubes yet, both are sitting on different horizon lines, all the values are off, especially in the modelling of the planes. And I would not bottom light anything. Not a good angle for figuring out cast shadows. The ground is too grey, and the cubes look very grey. Look at all the perspective charts Francis has supplied you all with, and use them as your guides. They will really help you to understand the volumes better.

Geelimp-yes they aren't even cubes. But you at least recognize it. The cubes, value wise look really dirty, not lit. And the shadows are a bit ambiguous. Especially the ends that are fading off into the light. By the way you painted the shadows, it looks like there are omni lights lighting the foreground. I would look at Spooge's image again to get some better reference where to go.

Affected-Your cubes are on the same horizon line sort of, but there seems to be an extreme fish eye type effect going on here. The cast shadows are flaring off in extreme, toward the horizon line...
The cubes are just slightly off from cubes. The tones do have a bit of gradation to them, but not enough. Again, like I emphasized above, get the cubes out in the sun, and see the light.
I am going to go home now, I will crit later...

[AliasMoze]

Thanks, Fred. Yeah, my cubes in both are poorly constructed. I'll post some done right. I've been working on more cubes, just can't get to the forum as much now to post.

I have a couple questions:

1) I'm assuming that, if the light is at a 45 degree angle to the cube, then the top and face of the cube would be lit evenly, with the face slightly brighter as the reflections hit it from the ground plane.

If higher than 45 degrees, then the top of the cube gets more direct light. If lower than 45 degrees, the the face gets more direct light.

Is this right?

2) I took some cubes out into the sun and made some notes. What struck me at first was how light the cubes were (this may be due to their translucency). No values seemed to go far below 50% or so.

Should I push the ramp and paint dark shadows anyway? Is this caused by my cubes being translucent? Do you know where I can buy some solid shapes (cubes, spheres, cones, cylindars)?

Thanks for the crits. I've been busy, but I'm a workin' on my cubes. I've had to do some backgrounds lately for cartoons and these exercises have helped immensely. This stuff is making me a better painter

------------------
AliasMoze
:) :) :) :)
"That activates my hilarity unit."

[Fred Flick Stone]

Alias Moze-I love hearing comments like that. Glad they are really helping. What I did beyond the Mr. Foamies was go to the Home Depot and buy wood shapes close to what I was looking for, I got everything but a cone. The cones can be made from bristol board. The cubes can also be made from a bristol stock or high grade white cardboard.
Yes, ramp up the values to high key, cause that is the way they are lit, with a white under surface. They are immensely brighter. The next step to this would be to go inside and artificial light them, after looking at the sun lit cubes, and compare, take notes. This is the difference in exterior, and interior lighting, or natural vs. artificial. The differences are enormous.
As for the 45 degree deal, anything above it would take on a more direct light, less value banding, higher intensity, but there will still be value transition...
Part 2 is coming soon. Good luck with all the work, and the learning...

Tell Moze I will be posting art on his tut. very soon...just been overworked...

[Fred Flick Stone]

joachim-next...nice. It almost fooled me that the shapes were pencil rendered...The cone seems a little flat. And the core is not very present. But as you mentioned earlier, you had never heard of core shadows before this. This is still artificial lighting, so I won't get into the comparatives of artificial vs. sunlit, plus the first crit I think I explained most of this stuff. I would try and stick with the same image till you have completed it to a satisfactory level, and you feel you have really acheived something in the lesson learned. Great efforts...Are you professioned as of now? I don't read alot of the personal stuff, just look mostly at art, so I am not sure if you ever mentioned it before. I believe though you work with Micke? Keep up the impressive work...

Hurri-cane-raw eh-top cube is skewed, not straight, top cube is too dark, second cube is an elongated box, not a cube, the sphere is not quite round, and the shadows on it are too contrived.The majority of everything with the exception of the sphere is grey, not white. Definitely get out in the sun with some paper cubes and see it for real, don't try and invent it. Can lead to some bad results,merely because you haven't seen it yet to know it...keep em up, and try to fix this image, and maybe eliminate the sphere for now and just stick with the flats...

Micke-I believe both of your boxes are on the same horizon line, but they are way too skewed...Meaning you have the vanishing points closing down too hard too soon, so the boxes actually looke pinched/skewed...

Faces on all the cubes look a little too flat in values. The cast shadow from the first box, cast onto the second box is way too light in value. This actually makes the second box look like it is slightly hovering above the ground plane. This is because it looks like the cast shadow of the first cube is slipping under the second cube...
The part of the cast shadow projecting toward us on the first cube, or the left cube looks a bit odd. The way you have identified the top corner of the box in the casst shadow is a bit too defined. I would imagine that from this angle of lighting, that corner would be skewed much more than it is making it less identifiable.
Everything looks a little bit on the grey side, rather than white. Rather than guessing at all this, get some bristol, make cardboard cubes, go out in the sun, and draw what you see. You seem to see this stuff much clearer when you have a source of reference. We all do. And this exercise is really meant to be done with actual props, so the eye can learn from experience, what the mind will later repeat in actual work, hopefully very intuitively as you practice this repeatedly, just like sports or anything else. Practice makes perfect...keep working out the problems in the same image till you have this one ironed out, then move to a new one. It is always best to spot the results, fix them and learn from it, rather than knw you made mistakes, but moved on instead. This can lead to some very bad habits, that will eventually lead to bad work ethics.

Wow, done with page three, only three more to go...

Iska-I personally like the way these were developed. Very painterly. Unfortunately, neither are perfect cubes yet. They are skewed and a little rough around the edges for this particular part of the exercise. This is more technical stuff, so even the paintings should reflect this feeling.

You have the right idea with how you worked up the values on the near sides of both cubes, with it darker along the bases of the faces(poetry), but the way you modeled up the values make the cubes look semi reflective, or a slight sheen to it. Much like the way brush aluminum would take on this type of light. The values on the right sides of the cubes though are off quite significantly. There would actually be no absolute black values between the cubes, since they are both white, and reflecting white back and forth onto one another. It would actually be much lighter in here. Also, the front cube faces are modelled the same way. The values are slightly different, but they are modeled way too identicalto one another to work effectively. Get some real white cubes and stick them out in the sunlight, and draw what you see. It will end up very different than the results you have here. And keep working on this image, improving it, until you have to really solid cubes. By then you will have learned a great deal, and you will see what a proper finished rendering looks like, done by your own hand...that is really important for further development...

That's all I am going to review on the cubes for tonight. I am going to try and get to the heads now for a bit. Keep those cubes coming, and look for part two of this exercise to be posted very soon...

[Fred Flick Stone]

I will try and conquer pages four and five by the end of this week. You all are fairing well, can't wait to see where all this leads for you guy's in you future endeavors. Keep arting...

[Sumaleth]

I just posted a new version of my shapes in the original thread, hopefully I have understood the things I needed to do?!

Fred, if I still don't have it right and you're sick of trying to describe all this in text you can try grabbing this file;
http://users.bigpond.net.au/sumaleth/sumalshapes_sml.zip

(1.4meg)

It's a quarter scale version of my PSD file - it would be very easy to use a big air brush and the layers to show exactly what these shapes should be shaded like.

It might also be a good practice tool for anyone wanting to try smooth shading and value selection. You could even remove the shadow layers and move the light source somewhere else for a real challenge.

Have fun,
Sumaleth

[Fred Flick Stone]

here we go again...

Mozeman-I am just going to go black and white with these descriptions, so don't be offended if I happen to rifle through these. I am trying to get all these wrapped up. But I have to stare at each one for a while to really dig up all the problems. Such is the case with yours. It isn't all that far off, but there are still some things to work out. Mostly in the subtlety of value. The cube is the least of your worries. The biggest problems with the cube: it isn't quite a cube, a little long in it's forward width, the dark side isnt all that bad, you definitely hit the highlight, or what you would call a highlight on that dark face. But, there would be a ridge of very dark value at the base of this edge. The area where there is no bounce light hitting the face. It would start at the closest bottom corner to us, and expand up the face at about a 20% angle up and off the face of the cube...this is again, the area that the ground plane is not influencing at all, because this part of the ground plane is also in shadow, and there are no other surrounding objects to influence that side of the cube. The cast shadow is a bit too dark, and is too soft all the way around the edge of it. The shadow would be very crisp starting ata the closest corner to us, and stay firm all the way back, the it begins to soften up, further from the object you go, the more diffused the shadow becomes. But this is also influenced by the scale of the object to the size and distance of the light. I am sure there is a math problem to figure this out, but I am an artist not a scientist. So, if there are any science minded people reading this that knows the answer to why and how this works, feel free to chime in at any time.
The sphere and cone have problems with there core shadows. The cores of the shadows become light influenced by all the bounce light coming back up from the floor plane, therefore the core shadows closer to the floor will be washed out, or diffused into the light, there will be an additional value transition, not only between the light and dark side of the sphere, but also in the dark side of the sphere, and cone(my bad). This is why these lessons are so valuable. Without seeing this stuff for your own eyes, tendency is to think on an object to object basis in any painting. But the reality is far from that. Everything influences everything. That is why we start with white cubes on white ground. Eliminate all the color, and the truth about form and the influence of light on the form becomes strikingly apparent. The cast shadows on both the cone and the sphere are not modelled correctly. The darkest part isn't in the center of the shadows. Check out the quick example I threw up on here to see the effects of the shadows on the ground plane. If I had to chose the right words for this, I'd be here all night trying to get it to sound correct. The picture is worth a thousand words...I am going to move on to the next cube now, if you have any other questions about this post, email me, or post the questions, I will get back to you ASAP...more likely by tomorrow...

Sedone-I would try to put the cubes next to each other, and turn each one in the opposite direction of the other, then side light from the front of the cubes, don't back light them yet. This causes a whole new set of problems that need to be addressed about the cast shadow and its projection onto the ground plane...as for the cubes you have, they are both resting on different ground planes, influenced by two different horizon lines. If the light is travelling in the direction your cast shadows say it is travelling in, then I would have to say that the faces on your cubes that are both directly facing us need to be much much deeper in value. They are far to bright to be considered in the dark side of the cube...The cast shadows are going parallel like they shoud be, put the second shadow on the nearest cube to us is far to short. If it is in the fron t of the other cube, the shadow should actually be a bit longer. The shadows are also too soft all the way around the perimeter of the shadows, and they are lit incorrectly. Look at the quick sketch I posted here to see the way the shadows are influenced by the objects and ground plane surrounding them...the cube in the far of the image would be much lighter on the dark side, by agbout 20%, because of the influence of light from the cube in front of it. And the value banding on the cube faces is too spotty, a spot of light in the top left, and a spot of dark in the right bottom are not quite the way it works. My strong recommendation would be to get some white cardboard or bristol, make two cubes, put them outside in the sun, and draw what you see. It will eliminate the headache of inventing something you aren't quite sure of, which is what I think is giving you a head ache over this assignment...but keep plugging away, eventually something is going to connect, and you'll be one happy camper...


Gimbal-here is your portion of the elephant...this cube, is a CUBE...the first one I have seen, besides Sumaleths...the one thing that is a bit strange though about the cube is the white outlines dividing the faces. A bit too much, weld those edges...the values are very flat on each of the faces of the cube. Look at spooges, sumaleths, and the example I posted on here to get an idea of how the values transition across the faces of the cube. More so, you should do the paper cube experiment to...invaluable...the cast shadow is too soft all the way around the perimeter of it, and the values aren't working correctly in the shadow. There would be the influence of the light fromthe cube boucning back into it. Again, the paper cube thing...there is also a black outline under the cube that makes it look like it is floating about a 16th of an inch above the ground. Fix the value banding in this image, get rid of the outlines in the cube, and fix the shadow, and repost. This one is very close...regardless of the corrections needed to tackle...

Affected-glad you are enjoying this. Learning can be fun, if you choose it to be...both the cubes are influenced by different horizon lines, both cubes aren't quite cubes, and I think you might be building the cubes with your vanishing points too close to the middle of the canvas, and that is causing way too much tapering on the cube shapes...the overall image is a bit too dark. Everything looks grey and lit, not white and lit...the way you have lit the dark faces is correct, in the general light flow on them. But the values are too dark, and it doesn't look like there is any real ground influence on the faces...Get out the cardboard cube, put it in the sun, and draw what you see. YOu will be shocked, that they end up looking nothing like these cubes. Plus, I think everyone is trying to invent these guys from their head, when you really should have a source of reference to learn from...Keep working this image out till you have it correct. You aren't all that far off...also check your light source and its influence on the cast shadows...it looks like your cubes are lit from a particular spotlight, causing the shadows to flair out as extreme as you have them here. Again, get the bugs worked out on this image, keep it, and use it for reference with regards to light influence on objects. This lesson, you will take with you for the rest of your art career...

General C-thanks for your post. It is fairly informative, so I am not going to hack the blue cubes up, though they should be white ...

Shorty-just learning to draw these are spectacular for never drawing before. The shapes are really cubes. WOW...the value range is correct for sun light, but the lighting is off. Both cubes look like they are being lit by two different light sources. The values on the second cube are a bit off on the lit side plane. Too dark. Did you make the cardboard cubes and observe them? The values in this particular image seem to read as such. But I could be very wrong. If you haven't done this exercise yet, I strongly encourage you to do so. There is no better place to learn about something than to actually have it in front of you, proof is in the pudding. Make some changes to this image and repost it. It's looking strong...

EEtu- it looks like your image is in a fog bank. A bit too hgih key to really define the values on the shapes...the vanishing points for the cube are too close to us, causing the cube to skew immensely. Next to a perfectly constructed cone, it looks misshaped. The values aren't quite right, but I can't say they are absolutely wrong either. If as I said, this were fog lit, then the values aren't that off, and the forms aren't far off either. But, the assignment calls for direct lighting, the sun preferably, so I would say, rework these guys to the correct lighting scheme, repost, and then we will dissect this image...


Synj-king of the picasso cube, I like the orange color, it makes me happy...

Zaphod-almost a cube. A bit long on the left side vanishing point...the cube looks dirty, more so than light influenced. It might just be the way the values were laid in. The way the values are banding on the faces of the cube are not quite correct either. Light just doesn't change value in the direction the light is projecting from...the object the light is falling on is also influenced by all that surrounds it, including the sky and the ground plane. There doesn't seem to be any influence from these regions in the values you have painted in. Same as the rest of the gang, you need to do the cardboard cube thing, it is the most rewarding thing you can do for yourself in this exercise. Keep posting the progression you are making...

Amnesia, and Dizzog-I will get to you guys tomorrow, and the rest of you by the end of the week. I am almost done reviewing all these YYYEEEAAAHHH!!!!!

[Gimbal]

Thanks for your time Fred. I have been away for quite some time and things have become increasingly problematic for me as far as time to draw/paint/etc goes. But as much as I whine and complain about the things going on in my life right now, I at least have a home to come home to. I'm really sorry to hear about your stressing plight. I have a friend who just got a job at a game company in Canada. He only now has an apartment he can move into on July 1st. Right now he is staying at a guest house that he has to leave from by the 25th of this month. I guess it'll be an extended hotel stay for a while for him. Just thought I'd mention that so you didn't feel like the only one in limbo.
Now if I can find where I put my newest cube I'll post it. But right now I better pay some of these bills I forgot to send out before I left last week (oops ).

[nori]

So I've been working with shapes some more and i'm wondering if I can get feedback on this cube. Not really sure 'bout the shades..

Also here is the .PSD incase anyone feels like downloading a 1.8MB file: cubert.psd