good morning community,
I need to render a product (20 ft. container) for a large format printing.
the print will be 700x300 cm.
I suppose to render at 150 dpi.
My keyshot run out of memory, so I thought I’m missing some information, or maybe I was doing something wrong.
What is your experience in cases like this (render for large format printing) ?
Apple M1 Max - 32giga ram
thx.
I once had to do a wall which was 1300x300cm and it was not easy, I’m not surprised you run out of memory.
KS renders to a window and after it finished it saves the render to disk. This comes with the behaviour that it needs a HUGE amount of memory for a render since it also needs to be displayed in full quality. And if you render all kinds of layers, it gets worse.
I ended up doing it in V-Ray because it has the option to skip the display but write the render directly to drive while it’s rendering. That’s not an option I often use because you don’t see the result, but it skips the need for reserving a lot of memory just to display the result.
My render was more a big kind of illustration and not a photorealistic one so in the end the renderer didn’t make much of a difference.
Saw that project was 4,5 years ago and currently I know a lot more about KS. What I would try to solve your issue is to split the scene in for example 5 parts and do region renders. Doesn’t need to be exact on the pixel since you can align the things afterwards in Photoshop. But it will save a lot of memory if you only render 1/5th of the width.
Another thing I remember I ran into was the limitation of a lot of file formats which can ‘only’ handle pixel sizes of 65535px max. That’s why I ended up in using 64000px wide. Was still plenty to get I think 200dpi which was more than enough for the purpose.
I also think I cheated a bit by rendering a slightly smaller size and using Topaz GigaPixel to upscale the image. It most of the time does a perfect job and back than I had a way slower GPU.
Hope this gives you some ideas. If you want you may also send the scene and I can try to give it a go as GPU render. Busy with more 2D today so some render in the background will keep the room a bit warm 
What I would try to solve your issue is to split the scene in for example 5 parts and do region renders
This is a very helpful hint Oscar!
I didn’t know you could split the scene into pieces. I don’t even know how to do this and I’m afraid that since it’s a 20 foot container rendering, it might be difficult to split the structure.
do you mean that if the size of the scene to render is 20000x5000 pixels (for example) I can make 5 scenes of 4000x5000 pixels each, splitting my object appropriately?
do you have any suggestions on how to proceed?
grazie Oscar
It’s pretty simple and you just select region, select like 1/5th of the width and you’re set:
What I do notice is that KS does keep the preview frame the full size. That’s a weird thing since you select a region and it should adjust the actual output render window and what it renders as well.
Maybe @jan.simon knows how this works internally.
If the memory consumed is the same you would still run into the same issue but that’s something you can try if you just render a few samples and see if it saves just the region or all and how the memory consumption is on the go.
In V-Ray it actually adjust also the final render size so if you still want a preview it’s a nice way to render really large images. Just be sure you don’t move the camera in mean time 
thanks Oscar, unfortunately when I saw the “Region” checkbox you were already writing…
splitting the rendering it seems that my Mac is able to do its job.
however I fear that today my poor knowledge of Keyshot comes out in the open.
to make sure that my container occupies all or almost all of the print area (700x300 cm) I have to zoom in closer to the container, is that right?
in this way however the container does not fit completely into the rendering area. I was thinking of moving by holding down the mouse wheel while dragging the scene to the left: is this a good choice?
I was unable to find the v-ray checkbox so as to render directly to the disk without taking up memory for display on the monitor…
in other words I am not sure I am performing the correct steps for this activity.
thx
we do renderings for tradeshow walls all the time, and we have found that rendering at 1/2 size and upscaling via Gigapixel by Topaz labs works great 90% of the time.
very interesting, thx Matt.
did you also test photoshop ai upscaling ?
p.s.:
the before and after of the locomotive is very funny.
using Gigapixel the locomotive is replaced and also the train station… ;D
Sorry Milko, V-Ray is a totally different render plugin used in a lot of 3D modellers. It’s absolutely unfriendly to learn compared to KS but has some great features I would love to see implemented in KeyShot.
For the size you don’t need to make it too complicated in your brain 
You can use the queue as well but I would try first if it would actually render. What I mentioned previous post is that KeyShot still shows that total size as preview window and not reduce it to the actual size of your selected region.
I’m not sure if that means it will also still consume the same memory (like all the black pixels around also will cost memory). If it’s just some visual thing I don’t mind but if the area outside the region would take up memory, I would say it’s a bug.
And that’s basically why I mentioned V-Ray, if you select a region to render it actually renders that region and doesn’t show and renders all black surrounding the region.
Like Matt says, GigaPixel works wonders especially if it can recognize what the objects are since its clever AI works less on fantasy things it didn’t learn. To replace objects is actual a pretty new option outside the normal rescaling AI, can give funny results. Using the normal rescale alghorythms is often really surprising. I never used the Photoshop rescale but if you for example upscale a bird in GigaPixel the output can have more details than the input. Cool.
150dpi is overkill for large format printing - you can easy go with 96dpi or even less - ask your printing company for exact value.
It mostly depends on viewing distance, so I think for a container @96 is plenty. An image for a huge billboard is smaller in megabytes than a poster in at some bus stop. And of course, the print process makes a difference, if it will be offset print in raster 40 I would still use 150dpi. And if I struggle with a real big size I use GigaPixel to cheat a last resample of the image to more pixels
However, even if I limit the rendering area, Keyshot creates an image of the dimensions defined by the print format and fills the image outside the rendering area with black. In short, a bit of a mess.
where am I going wrong?
that is normal. KS will render the black to keep the proportions the same. Might be nice if there was an option for that but from what I’ve used it for, pressing CMD+K in photoshop and duplicating the layer to the main document drops it exactly in the right place, where a copy/paste places it randomly then you have to line it up by hand. so, I like that it renders the whole artboard even if its in black.
As long as it does render that’s not a big issue. As Matt says you can just align thing in Photoshop. You can also use a default Photoshop script (File > Script > Load Files in a Stack) which simply will load all files from one directory (the renders you have) in one file just with all images in a separate layer.
If it finished loading you can just select a layer, draw a rectangle around the part with content and press the quick mask icon at the bottom of the layer panel.
You need to repeat that for the 5 (?) layers you have but you don’t need to align things since all renders have the same total pixel size and are just on top of each other.
Thx Matt and Oscar, no problem with PS.
thx for all advices
