Largest Size corona will render?

[Jpjapers]

I got a bad allocation error when trying to render an absolutely gigantic image (21000x35600).
Im going to try a render at a much smaller size but i wondered if there is a limitation somewhere in my system or the software itself that will cause issues with large images?
The image was for a huge wall vinyl if anyone was wondering.

[Juraj]

it's not uncommon at all to run out of physical memory (32 is not that much actually), if you want to render gigantic resolutions. I would bet this is your issue. Solution is tile render.

I know it's not what you asked, but I also have to comment just in case, was it the client who requested the resolution because he equated pixel density of glossy A4 magazine and just extrapolated it linearly to enormous proportions ?
Big wall prints are rarely even printed above 15-72 DPI, but even that doesn't mean your DPI has to match your PPI which can still be even lower. I can print A4 with 2.5K photo but still use 600DPI print, these values aren't necessarily connected directly.

And if your client really needs super resolution because he can't be reasoned with, just upscale it in post-production (fractal upscaling can be fantastic).

[Nekrobul]

Confirm Jurajs words.

We have rendered 10K image wich later was used to print a 30m x 10m gigantic banner.

Later i saw theese banners around riga and they were looking prefect.

Speaking about normal glossy paper prints 3.5k is more than enough for A3.

[Jpjapers]

Ah ok, Im fairly new to working with rendering for print. What would you recommend for an image this size? The wall is 2.65mx4.5m. Should i just take the size i have calculated and proportionately scale it until both values are below 10k?
The dpi isnt set by the client no, however it will be viewed up close so im thinking that 150dpi would have been better. Im waiting to hear back from our signage contractors on what dpi they would print at. Im hoping its 72!

[Juraj]

Just because it will be printed at 150DPI, still doesn't require you to scale your resolution to match it :- ) DPI is printing domain, it's none of your matter, it only dictates how much ink they will waste (and picture tonality, color blending,etc..)

PPI is your input, and rarely is it higher than 72 for 2m tall up-close read posters. You have 4 times that size, so 72 would super quality, not low.

https://99designs.com/designer-blog/2013/02/26/ppi-vs-dpi-whats-the-difference/

[Ondra]

you need at least 32 bytes per pixel (with no render channels). Only limit in Corona is 2 000 000 000 pixels total (44k * 44k) resolution. But 3dsmax limits both width and height of any bitmap to be at most 32k - so 3ds max cannot do 35k output, in any renderer