How long does it take to render an image decently?
- Thread starter JST
- Start date
Ralf
Alibre Super User
bigseb
Alibre Super User
Downloaded. Something I'd like to play around with if I get a chance.
JST, as Kyle says Keyshot is a CPU-based ernder package. Unfortunately your 2,5GHz dual core will be on its knees begging for mercy. I have a 4-core 8-thread i7 running at 3GHz and when I render Hi-res images (300dpi for printing) then they can take hours too.
Some things I have discovered when rendering:
-- Often the metal in the library isn't realistic to my eyes. So I go for what looks good and not for the right name. For example, if brushed steel looks fake then use brushed aluminium. Ultimately all materials will need tweaking (an argument against tying GD values to Keyshot values).
-- In terms of tweaking, yes its a PITA but each material can be and should be (my opinion) fine-tuned to suit the image be rendered. Don't expect a material to appear the same in each render either as environment, lighting, surrounding materials, etc will affect overall appearance. Take the time to learn the nuances and don't worry about the name. Create entirely unique material if you have to. Yes, this will take a lot of time with your CPU but it'll be worth it.
-- Also remember that lighting and environment can make or break a material's appearance. Again, play around and don't get caught up in names.
-- Lastly, to truly nail it you model has to be lifelike. I can't stress this enough. Take the lathe thingy on the first page. It has a lot of sharp corners; this will never render realistically. But add a fillet (even small, say, 0,2mm) or a chamfer and your model will look 'real'. Try it out.
JST, as Kyle says Keyshot is a CPU-based ernder package. Unfortunately your 2,5GHz dual core will be on its knees begging for mercy. I have a 4-core 8-thread i7 running at 3GHz and when I render Hi-res images (300dpi for printing) then they can take hours too.
Some things I have discovered when rendering:
-- Often the metal in the library isn't realistic to my eyes. So I go for what looks good and not for the right name. For example, if brushed steel looks fake then use brushed aluminium. Ultimately all materials will need tweaking (an argument against tying GD values to Keyshot values).
-- In terms of tweaking, yes its a PITA but each material can be and should be (my opinion) fine-tuned to suit the image be rendered. Don't expect a material to appear the same in each render either as environment, lighting, surrounding materials, etc will affect overall appearance. Take the time to learn the nuances and don't worry about the name. Create entirely unique material if you have to. Yes, this will take a lot of time with your CPU but it'll be worth it.
-- Also remember that lighting and environment can make or break a material's appearance. Again, play around and don't get caught up in names.
-- Lastly, to truly nail it you model has to be lifelike. I can't stress this enough. Take the lathe thingy on the first page. It has a lot of sharp corners; this will never render realistically. But add a fillet (even small, say, 0,2mm) or a chamfer and your model will look 'real'. Try it out.
JST
Alibre Super User
Let me start out by saying that I am fully aware that I do not entirely know what I am doing with Keyshot. There are things I don't know exist, things I don't know how to use, things I don't know what they are supposed to do, etc. I watched the videos, they are good slick marketing tools. It's very difficult to gain a real understanding from them, past "it's cool and it probably does what you want".
1) The lathe thingy was never intended as a rendering. It was from a different question quite some time ago. Just ignore it, I didn't even import it to this thread, someone else did. I used it ONLY as a comparison of processing times, which is why I think it was brought in at all.. The shiny surface deal is weird.... I have nothing to do with it.
2) Tweaking, sure. My problem is I have tweaked the thing until I was blue in the face and I still got nothing I liked, nothing that looked at all real.
As it happens, I am not concerned about ultimate detail. I do not need a diamond ring rendered, as in one of the videos. What I want is something which looks real. Real-looking has no actual resolution limit, things look real because they do, it doesn't suddenly start at 600 dpi, 1202 dpi, etc (as long as you stay out of solarization etc). A blurry photo can look real, or fake, and you know it when you see it.
The sink is particularly odd, because the top looks mirror-smooth, and the "bowl" looks like a rough cast surface. That CAN be right, because at a low angle, even a matte surface develops a specular reflection characteristic. (that's actually a measurement of roughness, the reflection angle). In this case I do not think it IS right.
The sink doesn't seem right even on the top. I can walk over a ways and LOOK AT a sink, and it doesn't do that. With reflections, I see the linear pattern in it, and the reflections follow that. NO WHITE SPOTS.
I can't find controls that let me get the appearance. "Bump" makes things worse, it isn't the right thing. Heavy brushed is wrong, it is "too much", AND it still tends toward the same problems I already see.
A BIG problem may be the "white spot issue". That is something KS seems to be doing. They may average out to be correct over the area, but they are artificial and wrong-looking, and I don't know how to get them to go away. They may be at the root of the sink bowl reflection issue.
3) Computer power.....
Maybe.... But when the rendering completes, that's all you get. It isn't a case of power (affects time to finish) but of the material model in KS, which does not get the desired result, and seems not to have ways to get there. Not ones I understand or know to use, anyway. I don't think computer power puts white spots in, either.
Computer power may affect the limits placed on the rendering, the selections, etc, and they may affect realism, of course. But even when I have set it to "slow and good" settings, I didn't see a change in the stainless brushed finish.
Maybe it's just too hard for keyshot to do.
4) Lighting....
Well, OK, but I am stuck with the lighting sources I have. That's where they are, and so that's what they will do. I can play with intensity and color within limits. Adding lights..... that won't cut it for an actual space.
Since I don't know how to fix it, really, the best stock material (still not really great) is "brushed radial" SS.
I attach a sink basin (no drain!) with the radial brushed.
Actually, no I don't, I can't attach a .ksp file here. Nor a .bip. Well phooey.
1) The lathe thingy was never intended as a rendering. It was from a different question quite some time ago. Just ignore it, I didn't even import it to this thread, someone else did. I used it ONLY as a comparison of processing times, which is why I think it was brought in at all.. The shiny surface deal is weird.... I have nothing to do with it.
2) Tweaking, sure. My problem is I have tweaked the thing until I was blue in the face and I still got nothing I liked, nothing that looked at all real.
As it happens, I am not concerned about ultimate detail. I do not need a diamond ring rendered, as in one of the videos. What I want is something which looks real. Real-looking has no actual resolution limit, things look real because they do, it doesn't suddenly start at 600 dpi, 1202 dpi, etc (as long as you stay out of solarization etc). A blurry photo can look real, or fake, and you know it when you see it.
The sink is particularly odd, because the top looks mirror-smooth, and the "bowl" looks like a rough cast surface. That CAN be right, because at a low angle, even a matte surface develops a specular reflection characteristic. (that's actually a measurement of roughness, the reflection angle). In this case I do not think it IS right.
The sink doesn't seem right even on the top. I can walk over a ways and LOOK AT a sink, and it doesn't do that. With reflections, I see the linear pattern in it, and the reflections follow that. NO WHITE SPOTS.
I can't find controls that let me get the appearance. "Bump" makes things worse, it isn't the right thing. Heavy brushed is wrong, it is "too much", AND it still tends toward the same problems I already see.
A BIG problem may be the "white spot issue". That is something KS seems to be doing. They may average out to be correct over the area, but they are artificial and wrong-looking, and I don't know how to get them to go away. They may be at the root of the sink bowl reflection issue.
3) Computer power.....
Maybe.... But when the rendering completes, that's all you get. It isn't a case of power (affects time to finish) but of the material model in KS, which does not get the desired result, and seems not to have ways to get there. Not ones I understand or know to use, anyway. I don't think computer power puts white spots in, either.
Computer power may affect the limits placed on the rendering, the selections, etc, and they may affect realism, of course. But even when I have set it to "slow and good" settings, I didn't see a change in the stainless brushed finish.
Maybe it's just too hard for keyshot to do.
4) Lighting....
Well, OK, but I am stuck with the lighting sources I have. That's where they are, and so that's what they will do. I can play with intensity and color within limits. Adding lights..... that won't cut it for an actual space.
Since I don't know how to fix it, really, the best stock material (still not really great) is "brushed radial" SS.
I attach a sink basin (no drain!) with the radial brushed.
Actually, no I don't, I can't attach a .ksp file here. Nor a .bip. Well phooey.
TylerDurden
Alibre Super User
Ja, the mill assy was just a test to compare render times and verify there wasn't something horribly wrong with KS on JST's machine.
The speckles seem to be a known problem in KS, other users have avoided them to some degree by materials choice and roughening.
The splotches were indeed the caustics.
The attached image was rendered for only an hour using the time-restricted mode. There are still patterns in some smooth surfaces that might resolve with more sampling and time.
I roughened the sink bowls some to try to get around the speckles, but it may need another material altogether. Lighting intensity was reduced, that seems to help a bit.
Based on the render time comparisons, I'd say JST's machine could easily take >24hrs to get a clean image, depending on the settings and materials.
The speckles seem to be a known problem in KS, other users have avoided them to some degree by materials choice and roughening.
The splotches were indeed the caustics.
The attached image was rendered for only an hour using the time-restricted mode. There are still patterns in some smooth surfaces that might resolve with more sampling and time.
I roughened the sink bowls some to try to get around the speckles, but it may need another material altogether. Lighting intensity was reduced, that seems to help a bit.
Based on the render time comparisons, I'd say JST's machine could easily take >24hrs to get a clean image, depending on the settings and materials.
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JST
Alibre Super User
That would be better than needed, if the sink looked better, and the speckled white dots were gone.
I'm OK with longer, don't have a lot of choice now. Don't do that much large scale rendering.
Thinking of finding a machine to dedicate to rendering, this one is fine for GD.
Do you suppose larger memory would speed up KS on this machine in any significant way? I can do that without pain.
I'm OK with longer, don't have a lot of choice now. Don't do that much large scale rendering.
Thinking of finding a machine to dedicate to rendering, this one is fine for GD.
Do you suppose larger memory would speed up KS on this machine in any significant way? I can do that without pain.
Ralf
Alibre Super User
I think, RAM is not the problem in this case, but the "missing" amount of cores is the problem.
You can make a test: Start KS with your model and hit: H on your keyboard ( Heads-Up Display)
Please take a look, I send a screenshot with an intel i7 6 core + HT = 12 cores - 4.2GHz
My FPS value is 2.6 in realtime mode @ 1376 x 1032
.
You can make a test: Start KS with your model and hit: H on your keyboard ( Heads-Up Display)
Please take a look, I send a screenshot with an intel i7 6 core + HT = 12 cores - 4.2GHz
My FPS value is 2.6 in realtime mode @ 1376 x 1032
.
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jhiker
Alibre Super User
I am no expert but I have a few observations.
This is a screen cap of a 3-hr render with bounces/shadows, etc. at a more-or-less standard settings.
I've reduced the scale of the scratch maps on the stainless sink and I think it looks better but not perfect.
The kitchen scene is 'enclosed' but it does have some open doors and windows and thus the environment (dome) lighting will have some influence.
I've put a blue backplate on there so you can see where the kitchen model is 'open'.
Interior lights are very tricky to set up correctly and the effect can vary wildly. Altering the 'Scene units' in the 'Edit' tab changes things dramatically.
I've been told it's best to use the dome lighting to get as close as possible to the desired effect, bring the lights in cautiously after that and use sparingly to avoid the possibility of 'speckles'.
Anyhow, for this scene I removed (hid) the ceiling and lit the scene with the 'Classic kitchen' environment, toned down the scratches on the stainless steel and reduced the lighting somewhat.
Incidentally, Keyshot 6 (in beta right now) has an 'interior' lighting mode which should help in these situations. I'll have a go with that and post the results later.
This is a screen cap of a 3-hr render with bounces/shadows, etc. at a more-or-less standard settings.
I've reduced the scale of the scratch maps on the stainless sink and I think it looks better but not perfect.
The kitchen scene is 'enclosed' but it does have some open doors and windows and thus the environment (dome) lighting will have some influence.
I've put a blue backplate on there so you can see where the kitchen model is 'open'.
Interior lights are very tricky to set up correctly and the effect can vary wildly. Altering the 'Scene units' in the 'Edit' tab changes things dramatically.
I've been told it's best to use the dome lighting to get as close as possible to the desired effect, bring the lights in cautiously after that and use sparingly to avoid the possibility of 'speckles'.
Anyhow, for this scene I removed (hid) the ceiling and lit the scene with the 'Classic kitchen' environment, toned down the scratches on the stainless steel and reduced the lighting somewhat.
Incidentally, Keyshot 6 (in beta right now) has an 'interior' lighting mode which should help in these situations. I'll have a go with that and post the results later.
Attachments
jhiker
Alibre Super User
Here's the V6 beta image with 'Interior Lighting' mode on and a different Environment for comparison. I could have adjusted the stainless steel a bit better, I think.
This one still has the ceiling in the model so the interior setting must be doing a lot of work in this scene.
This one still has the ceiling in the model so the interior setting must be doing a lot of work in this scene.
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JST
Alibre Super User
Yes, there is a ceiling, part of the deal is investigating can light placement. So the exterior light is reasonably irrelevant... I could put a blank area in the door/window openings, but it likely won't do a lot for render time or accuracy.
When I set it up, I used the default units, whatever they are, and they are apparently not easily changed, without working out the conversions.
The radial brushed stainless looked the best of the stock materials. I am doing poorly with modifying.... it doesn't get better when I change things, I don't yet know how all the settings work
When I set it up, I used the default units, whatever they are, and they are apparently not easily changed, without working out the conversions.
The radial brushed stainless looked the best of the stock materials. I am doing poorly with modifying.... it doesn't get better when I change things, I don't yet know how all the settings work
TylerDurden
Alibre Super User
OK, here's a render that might be passible to a client.
I reduced the lighting, added some roughness and killed the bump mapping from the brushed metal materials, and set the reflections to one bounce. The reduction in reflections should help lower the render time.
I set the time constraint to two hours, which might translate to about 48hrs on JSTs machine. It would be nice to get that down to overnight or at most 24hrs.
BIP is here: https://dl.dropbox.com/s/r9ryrbs70bilrik/kit1.ksp
I reduced the lighting, added some roughness and killed the bump mapping from the brushed metal materials, and set the reflections to one bounce. The reduction in reflections should help lower the render time.
I set the time constraint to two hours, which might translate to about 48hrs on JSTs machine. It would be nice to get that down to overnight or at most 24hrs.
BIP is here: https://dl.dropbox.com/s/r9ryrbs70bilrik/kit1.ksp
Attachments
JST
Alibre Super User
yeah, that's nice indeed.
In fact, for now, this is all I really need at present, and it was just a couple hours time. The time to get to virtual perfection could be as long as you have. This would print as well as most, and there is little to be gained by waiting 5x longer or more. One down sampling of the JPG and it would be fine, for instance.
2 bounces, no caustics, I adjusted the gloss on the cabinets down enough to avoid specular reflections, and the metal is radial brushed stainless, not modified. Sink looks far better than it did before after more time, and far more realistic, also. If I knew better what I was doing, I might be able to improve even it.
For simpler scenes, a couple hours rendering would likely look just about as good as Tyler's.
No idea why the KS site is so fussy, something over there may be AFU, it does NOT like any computer I have tried, with OS and matching browsers from 8.2 back to XP.
In fact, for now, this is all I really need at present, and it was just a couple hours time. The time to get to virtual perfection could be as long as you have. This would print as well as most, and there is little to be gained by waiting 5x longer or more. One down sampling of the JPG and it would be fine, for instance.
2 bounces, no caustics, I adjusted the gloss on the cabinets down enough to avoid specular reflections, and the metal is radial brushed stainless, not modified. Sink looks far better than it did before after more time, and far more realistic, also. If I knew better what I was doing, I might be able to improve even it.
For simpler scenes, a couple hours rendering would likely look just about as good as Tyler's.
No idea why the KS site is so fussy, something over there may be AFU, it does NOT like any computer I have tried, with OS and matching browsers from 8.2 back to XP.
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