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Rendering, it's more than a five min process

Rendering, it's more than a five min process

Rendering, it's more than a five min process

(OP)
Hi guru's
I'm playing around with some of the advanced settings in photoworks 3, and my part is starting to look pretty darn cool.  However......I find that the part on my screen is far lighter in shade than my rendered part.  It takes about 5 min to render each time after I make a change, i could spend days doing this (not by choice either).
Also the printed version is different in shade and colour.

Is this a normal process?  Any tips or links would be greatly appreciated.

Thanks

Gerry
www.scatmat.com

RE: Rendering, it's more than a five min process

Color representation on a monitor will hardly ever match the printed page. About the best you can do is to try to adjust your color and gama settings of your monitor to match what your printer is printing.

Ray Reynolds
"There is no reason anyone would want a computer in their home."
Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Rendering, it's more than a five min process

Scarecrow.

PW2's default gamma setting is 1.5.  I find if I change it to 1 the screen image and the printed image are a lot closer in apperance.  They still are not perfect but usually acceptable.  The shading os your model bears no wieght on your PW rendering.  You could have your model shaded any color but rendered in black.

Here are a few sites with PhotoWorks rendering samples.  They don't give any information on how to use PW but it lets you see what is possible.  www.zxys.com  www.mikejwilson.com www.bxhdesigns.com

RE: Rendering, it's more than a five min process

You also might want to look at www.povray.org. I've been using Pov-Ray raytracing software since '92, since pov-ray is a very powerful raytracing software the principals I've learned have helped me get a lot closer on my first render. Also some things only increase the overall quality of the image and dont really help test renders. Turn off these functions if you can.

As with all photo-rendering software CPU speed and RAM are usually the rate controling factors.

nick

RE: Rendering, it's more than a five min process

It's been a while since I've had to render anything.  God willing, it will be a long while still.

2 things I learned about rendering that always seem worth retelling:

1.) A screen never looks like a print.  Screens are backlit; paper is not (unless you hold it up to a window).  It may be necessary to do separate renderings for different media.

2.) For the pupose of tweaking material settings and lighting, try experimenting on simple shapes like cones and blocks which render much faster.  Alternatively, use a simplified version of your model or a small piece of the model.  This can really cut the amount of time it takes to adjust.

"Great ideas need landing gear as well as wings."--C. D. Jackson

RE: Rendering, it's more than a five min process

Scarecrow,

We render things all the time.  One thing we noticed is that a screen rendering is normally lighter than a rendering to a file.

Some things that will save you some time:
1.  Make small screen renderings before rendering to a larger file to check your settings.  When doing this:

a.  Allow shadows at their lowest quality setting.

b.  Don't render with your window maximized--make it about 1/4 screen size

2.  Don't use indirect lighting unless necessary--this takes a great deal of resources and also requires different reflective properties of each material than direct lighting (default) settings take.  If you use indirect lighting, start small and work your way up with screen renderings as mentioned above.

Brian Hill at BXH Designs gave some of these hints to me--his renderings are incredible.


Jeff Mowry
Industrial Designhaus, LLC
http://www.industrialdesignhaus.com

RE: Rendering, it's more than a five min process

You need devices and softare that have a color management system, I believe its called. This helps to match colors on different devices that use different color spaces and methods for generating those colors. Not all displayed colors on a monitor can be printed with standard inks and not all printed colors can be displayed on your monitor.

If you have the proper hardware and software and its properly calibrated and you are careful with your color ranges it seems that you can get close on a print to what you see on the monitor.

RE: Rendering, it's more than a five min process

There's a good discussion about this issue on Tek-Tips on the PhotoShop forums.

Basically, the problem stems from the fact that monitors display colors in the RGB gamut, which are additive in nature while printers print in the CYMK gamut, which are subtractive in nature.

The best you can hope for is to adjust your monitor contrast and brightness to emulate the printed page.  Monitors display colors more vividly since the images on the screen are basically backlighted.

Another good thing you can do is use Patone colors values.

Ray Reynolds
"There is no reason anyone would want a computer in their home."
Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Rendering, it's more than a five min process

Its not the fact that monitors display additively with a RGB or derivative color space and print in a subtractive such as CMYK or CMYKOP space but the fact that the light in your enviroment and the settings on your device vary.

For example with a monitor you can adjust color temperature, brightness, and contrast. With your video card it is possible to adjust gamma and color curves. So what you see is not just a function of what RGB value a bmp is telling the computer to display at a given pixel. Therefore a pure red rgb(255,0,0) block will look different on 2 or more different monitors even though both of them are additive devices. That's why its important to calibrate the monitor to some standard and view it in proper environmental lighting.

So if red isn't red from monitor to monitor how is your printer suppose to know what your monitor is displaying? It doesn't. Thats why devices can be assigned color profiles and such. Do a google or yahoo search on some of these terms: gamut, "color profile", "color management system".

RE: Rendering, it's more than a five min process

PhotoWorks 2, etc. is much slower than the original, because it uses a different rendering engine from a different software company.  It is much more capable and thus doing much more complex computation.  Basically you are blowing the mind of your little CPU.

Now..... I wonder if Photoworks can make good use of  multi-threading (thus dual processors)?

Be naughty - save Santa a trip.

RE: Rendering, it's more than a five min process

Yes Photoworks2 is able to multithread and use all available processor time. (at least thats what taskmanager tells me).

nik

RE: Rendering, it's more than a five min process

Thanks, NickE, good information.  There was another post going referring to this subject, hope they read this. My manager is going to have $#!* fit when I ask for duals next time we upgrade our hardware, heh,heh,heh.....

Be naughty - save Santa a trip.

RE: Rendering, it's more than a five min process

Ahhh but dont the sales guys really like the ray traced photos of pie-in-the-sky designs? get them to fork up some cash to pay for the dualie....

nick

RE: Rendering, it's more than a five min process

Well, we don't really get chance to do pie-in-the-sky stuff. All our designs are the real thing. Its expensive to design our stuff and someone has to pay for it, either us or the customer.  

However they do fly.....   (We do Head Up Displays and Head Up Guidance Systems (tm) for transport type aircraft - commercial - regional - military and biz.)

Be naughty - save Santa a trip.

RE: Rendering, it's more than a five min process

Shinies (marketing folk, etc.) often like to see pretty pictures before committing to the cost of engineering the guts of a product.  This depends, of course, on your industry.  If consumer goods, this is normal.  If it's more toward industrial, you really don't have too many Shinies to please most of the time--a nice burden lifted, since Shinies often tend toward irrationality and frustrate the rational.

So, we often give Shinies what they want up front and fill in the works after approval--and charge them for both--but that's the way they like it.  (Hope that doesn't sound too disparaging--jaded is more what I was looking for.)


Jeff Mowry
Industrial Designhaus, LLC
http://www.industrialdesignhaus.com

RE: Rendering, it's more than a five min process

Yeah.... interesting how we all have different uses for pretty stuff.  Maybe some good reasoning to give both PW and RealityW.  I mostly use it at home for my own stuff, which is usually overkill, but it's cheap......  Getting on the ground in thick fog and such is important to our customers - doing it with pretty equipment is kinda secondary.  Also the guys buying it are not the guys who have to fly and look at it.  However one famous quote is long remembered here "It's a really great system, but it looks like the Russians designed it 20 years ago."  It would be interesting under some other thread to find out what eveyone is using PW for and how much of its features they are really using.  Seems like we could get some very useful FAQ out of it.

Be naughty - save Santa a trip.

RE: Rendering, it's more than a five min process

(OP)
ok i'll start,
We use (well are hoping to) photoworks for pre-sales drooling.  Basically we come up with an idea, in order to pre-sell that idea a nice glossy picture is required to get all our distributors pumped up.
I see realistic rendering being a very valuable tool for future employment, pre-sales, and marketing surveys.

I see solid modeling being split into two professions: Modelling and life like rendering.

An intersting topic for sure, anyone else willing to share their info on this?

Gerry Bolda
Product designer
www.scatmat.com

RE: Rendering, it's more than a five min process

Me next.  We use it for the same thing.  I probably use PW as much as SolidWorks.  We do quick models of very expensive "fictous" custom products and render them to make them appear real.  We try and sell the product right from the rendering.  We then do the actual models and drawings for the products.

RE: Rendering, it's more than a five min process

My clients often have customers of their own they want to sell things to.  So they ask me to come up with the quick concepts that look good.  (I refer to such a model/rendering as a "Hollywood".)  The sale is often made (and ridiculous promises too--notorious Shiney talk) based on the Hollywoods.

Then comes the "simple" work of making everything function according to the inflated promises by the Shinies.  I often hear something like, "Well, it's already done, isn't it?  It's right here--just finish it up."  (Mind you, this is a Shiney client, not the end customer.)  I am continually baffled by this, but it makes the gears go round and pay the bills, so that's the way it goes--besides, I'm used to it now anyway.
                                      


Jeff Mowry
Industrial Designhaus, LLC
http://www.industrialdesignhaus.com

RE: Rendering, it's more than a five min process

Hollywood.  I like that.  

If only the shinies could sit in our seat for a day or two.  I mean all they would have to do is push a button and go get some coffee.  The computer would do the rest.

Our jobs are that simple.  Aren't they?

RE: Rendering, it's more than a five min process

Same here, last week in fact I designed two assemblies, (cant tell ya what for, I'd have to kill ya) that may never see production. The PW renders are in our advert. in machine design thou. Photoworks is ok :( I prefer the power and speed of Pov-Ray thou, just haven't got a good way to generate good scenefiles in Pov-Ray direct from SW, Tesselated shapes are not good objects to render. Pov-Ray likes equations....

x^2/a^2 + y^2/b^2 + z^2/c^ = 0

nick

RE: Rendering, it's more than a five min process

We don't deal with renderings, and that means I don't get to play with PW (too bad for me).  But we do built proof of concept prototypes after we have the CAD model finished.  I am always surprised at the sales folk that see the prototype working then go out a sell the heck of the product before we've even had the chance to optimize the design.  Thier belief is the same, "I saw it built, so we must be able to sell it."

Usually a few weeks after the prototype is shown in-house, we'll have orders placed for customers.  I guess people think you can go directly from design to selling, and by-pass that small hinderance of "production".

Ray Reynolds
"There is no reason anyone would want a computer in their home."
Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Rendering, it's more than a five min process

Is that where I heard the following line from (I forget the name of the movie), "Technology, it's almost as good as magic."

Ray Reynolds
"There is no reason anyone would want a computer in their home."
Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Rendering, it's more than a five min process

Wow, you guys get to have all kinds of fun.  We rarely use PW.  Only very occasionally do we make a rendering if it is for an important proposal or a marketing publication, etc.  Mostly they use photos.  We rarely get all the consol and panel details, plus seat, contol column, etc in enough detail to make them look realistic.  It is usually just aircraft structure details and windows, glareshield, etc.

Be naughty - save Santa a trip.

RE: Rendering, it's more than a five min process

Reality exists almost completely in the details as far as renderings go.  Add a few minor things, like mundane objects for scale or scenery and you're on the right track.  Decals make a huge difference.

I'm planning to model and render my coffee mug soon--boring, right?  Simple model.  However, this is a real mug with my coffee in it and evaporation lines, drips, and all the other slobby things about a well-used mug.  The idea is to build a photorealistic rendering and tutorial for how to create the effects in PhotoWorks.  It will probably take about three hours to do everything, including the creation of the decals and coffee lines--from scratch--and I hope the results will be great.

Now I just need to find an extra three hours somewhere.  I'll post the rendering on my site when I finally get it done--with a basic tutorial oriented toward adding detail when time allows for that as well.  PhotoWorks is a powerful tool when used creatively.


Jeff Mowry
Industrial Designhaus, LLC
http://www.industrialdesignhaus.com

RE: Rendering, it's more than a five min process

(OP)
I ordered "Digital Lighting and Rendering"by Jeremy Birn (ISBN 1-56205-954-8).
It's easy to follow for newbies like me, and after only a few pages into the book my renderings are looking much better.

Gerry Bolda

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