nanoDLP

mandreas

Member

Registered: 2016-03-13

Posts: 136

exposure time ranges

Dear Shahin , I want to renew my gratitude for the beautiful work you have created,

I will set out to you for advice, for future upgrades:
exposure times configurable by the user into layer ranges (of infinite number), example:

from layer 0    to  layer 25   --- exposure time 20 sec,
from layer 26  to  layer 100 --- exposure time 15 sec,
from layer 101 to layer 300 --- exposure time 7 sec, etc.

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,541

Re: exposure time ranges

Thank you Mandreas,

Can I ask you how it could be useful? Is there any resin which could be cured in such wide range?

mandreas

Member

Registered: 2016-03-13

Posts: 136

Re: exposure time ranges

Perhaps this feature would be useful for people like me, using the "top down" system, which produces bulging on large surfaces,
but thinking back, probably you're right with your question, as the dimming is the obvious answer,
another interesting option could be the extension of exposure in thin pieces, watch the video as the jet Pro uses this function
https://youtu.be/usJGwwadHMk

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,541

Re: exposure time ranges

Very interesting. have not seen this one.

Do you think it will be useful addition to dimming?
We already have such function on calibration printing. Have you seen it?
But for plate printing I believe our rendering engine need major update. I will try to get couple of opinions on the feature.

mandreas

Member

Registered: 2016-03-13

Posts: 136

Re: exposure time ranges

yes,
I have seen the dimming function is really well done, a workhorse of the program I think!
It might be useful, for example, a function that extend  of "n" seconds the exposute , on any surface 100% clean not directly  in contact with dimmed surface, but should do tests

joaoreina

Member

From: Paris, France

Registered: 2016-02-19

Posts: 20

Re: exposure time ranges

Hi,
I have one comment and question about these issues

- I think the feature proposed by mandreas is quite interesting, I've also been thinking about a work hypothesis which involves configurable exposure times per different layers. I was also thinking that you could take advantage of the already implemented feature of applying blackouts. Instead of a 100% full blackout cover, one could define a cover with a configurable % of either exposure time and/or dimming, and why not, define as well to which layers it should be applied. Just a thought, have no idea how easy/hard these things are to implement

- my question is about the dimming feature, if I got it right, what are defining a perimeter with a custom thickness and a dimming percentage in the center of the object slice, right? similar to the FDM perimeter/infill features?

congrats on the great software, Shahin
best

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,541

Re: exposure time ranges

There are couple of differences. Dimming's main advantage is over-cure prevention. It does not save any resin. Final structure is same as solid model. It just try to disturb light evenly as much as possible. For me at-least, it have saved money too as it extend PDMS life time.

I was not sure if dimming feature would helps at all but changing cure times based on thinkness of pieces was annoying. Final result of dimming exceed even my highest expectation.

I agree with mandreas, it should be tested. It is a time consuming feature to develop. I have couple of high priority features in pipeline. After that I will try to work on this one too. Still it is not clear what kind of advantages it will have over dimming feature.

adam

Member

Registered: 2016-02-18

Posts: 100

Re: exposure time ranges

there are also methods of multiple exposures on one layer to reduce warping due to shrinkage on large surfaces. Imagine having a checkerboard pattern projected, and then the opposite pattern on the same layer, it is used to help mitigate some forces that are in play during shrinkage i guess.
Probably some extra care needs to be taken when implementing features like that because the multi-exposures-per-layer method is patented by a well known german manufacturer