It can get a little confusing, but less cure time is needed for the clear because light travels further, so the laser cures it in shorter bursts to avoid overcuring. With dark resins, the lasers blasts them for a longer time and with more intensity to cure the same depth.
@EvanFoss would you try my sample at 0.025mm as well?
@David_Closs Umm the effects of flare still arenāt understood well. The main body of knowledge on the topic is to the best of my knowledge this thread. You can run the sample prints to see if you have the known signs of it. If you have a theory explaining your artifacts with flare you could attempt to test that. However I donāt know if anyone can tell you much more yet. However Iām not sure why you would think those artifacts would be related to the tank either.
@Everyone Else sorry for the spammy run of replies it wasnāt intentional.
I really donāt know what to do with formlabs support. My open ticket is currently focused primarily on this topic. I have explained that I believe laser flare is adversely effecting my prints. I have explained that my test part was designed to exacerbate this effect, resulting in very poor surface quality on one side. I have explained this is also to demonstrate a correlation between the poor surface quality and the flare by showing the problem occurs on the side that lines up with the flare. I have explained that I hope to eventually demonstrate to formlabs that the flare is actually the cause of problems with my prints, not the mirrors or some other thing that they can just have me clean or replace away. I have explained to them I hope that if this is clearly demonstrated to them they will cover this defect under warranty and correct it. In response to my recent pictures of my print of my test part I got the following response.
This is actually the second time I have had support offer to reorient a part for me when the whole point is to demonstrate a flaw in how the printer prints when certain circumstances occur. This is also far from the first time I have gotten a response like this from support, as a matter of fact a lot of my history with them is similar to this. I am at a loss for words. How should I respond to this.
In addition to this, max. laser power is fixed and at some point you need to start going over the same portions multiple times to get the same cure depth. Obviously, the more times you pass over the same portion, the worse it gets (on top of the already maxed out laser power).
I do think the flair has problem if not on an immediate model but the longevity of the resin in the tank since even stray light will degrade the resin. If the resin is left exposed in just room light it degrades.
I constantly empty my tank through a strainer back into the container with the rest of my resin. So with this in mind I am also mixing in partially exposed resin back in.
So far it doesnāt seem to be a problem and so far clearing my tank out between prints and keeping the tank empty has kept my pdms like new through 2 liters. I print a lot of big flat items and donāt necessarily use supports in these cases. But I do notice that the tiny areas do tend to need a little more work to clean where they might be slightly over exposed from possibly the flair or just the nature of the system.
As far as the resin I am using it does settle way too fast and parts on supports arenāt really possible since it fails after 1/4" up at 50Āµ. However for the types of printing I happen to be doing I am getting far better results on my flat parts (direct on build platform).
As Josh pointed out is a choke possible on these? Maybe a focus lens? Are there other brands of lasers that we could just plop in that match the specs of the current laser?
How much do these lasers cost on the open market?
@KenCitron The solution was pointed out repeatedly by @Ante_Vukorepa. A better laser would come at a much better price point and would most likely have a similar problem but possibly less pronounced.
@RocusHalbasch I have tried to search backwards in this thread for the post where you shared this file and I have not managed to find it. Would you please post a link to it or something. At almost 200 posts this is becoming impossible to follow.
Sure it is post #165. You can navigate with the post number box in the lower right, or use this link.
@RocusHalbasch Ok I found it. Is it ok if I print it in clear or do you need to do it in black? (i am down to 1 resin tray right now)
Clear v1 seemed to show the problem for one person who was having issues. However another person tried clear v2 and didnāt seem to show problems but he also hadnāt been experiencing print problems. Iām pretty sure clear should show roughness but not positive. Iādo say give clear a try if it shows roughness then there is clearly a problem if not then there may or may not be a problem and you can try black some other time. Really as many different samples as we get help.
@SachaGloor - Thatās one great looking print!
@KenCitron - I agree, we all need to be testing with the same resin and print settings. I also agree with your comment below, however Iām not sure I would mix the new with the used resin.
@RocusHalbasch - I agree and donāt think re-orientating the print is a long term solution. It was my belief that the purpose of orientating a print was to minimalize the print surface area to reduce peel related issues. For example if you were to print a solid cylinder you would orientate it vertically as this give the smallest surface print area. At the moment, because of the laser flare issues, this also meant that you are also going to increase the amount of strainable part cured resin after each print as well as poor surface quality.
IMO this is due to the laser continually passing over the same area of resin. I agree that a quick fix would be to orientate the part at 45 degree to keep each laser pass, as far away from each other, but does not address the underline issue. I also agree with @KevinHolmes, that the laser flare degrade the resin in the tank and after a few print / straining cycles is not at all optimum.
@Steve_Johnstone re-orienting the part actually completely misses the point. This part was designed to cause a scenario that shows a flaw in the way the printer works even if re-orienting it meant you could print this part perfectly it would be irrelevant. The problem is not that I can or can not print this particular part and have it come out correctly. The problem is that when any part is oriented such that things line up in certain ways there will be unacceptable artifacts due to the flare. If you are rotating an object to avoid the artifacts that result from flare you arenāt rotating it, as @Stephen put it, āto better suit the way the printer is designed to operateā. You are instead rotating it to avoid artifacts from laser flare that is there do to poor quality assurance, flawed design, or poor sourcing of parts. It is clear from the fact that formlabs repeatedly denied flare could adversely effect any print that flare was not in any way factored into how the printer was designed to operate. Therefore it seems blatant to me that the if the issues with surface quality are indeed due to flare this print is a clear demonstration of a defect.
If you purchased a 2D printer and later discovered that when you printed anything that went all the way to the right of the page that the printer would leave extra ink that would build up and eventually get on the print head and cause streaking, blobbing, and other problems on the print. Then you contacted the manufacturer and they said āthat is not possibleā. Then you created a simple file to illustrate the problem that just prints a thin line down the right hand edge, but because of the defect results in a page with streaks all over it. Then you printed this file and sent them pictures of the results to show them the defect in action in hopes they would admit the defect exists and fix it. Would it not seem ridiculous and insulting if they replied suggesting you add margins to your file and asking if you want them to add margins for you.
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Sorry @RocusHalbasch, that was a typo my end. Iāve edited my post to read " I agree and donāt think re-orientating the print is a long term solution" i.e. I totally agree with all that youāve said and reorientation the print doesnāt address the issue that youāve identified.
Yes we can work around it to some extent, but we still end up with wrecked resin and it also adds another variable into understanding why a print may have failedā¦ hope that makes sense.
If your part prints poor even with new orientation, I would like to see what they say about that.
@Steve_Johnstone sorry for the rant, the frustration you noted was not with you at all. I just get sick of formlabs support. I have had problems with every printer I have received from them and getting them to actually admit the problem exists and do something about it is maddening.
Itās hard for any company to admit there is an issue in public. Whoās going to admit it? Only the president of the company can. Support, engineers are just employees. Itās not their call to admit to anything 
So the only hope is that they are on top of it, and that they are working on fixing the issue. From what I hear, they are going through all the parts to make sure any other part of the mechanism isnāt responsible for causing this issue, not just the laser. Iām sure if they figure out itās the laser (which most of you here including me suspect that it is), they will most likely source a new laser and replace them. I donāt think they will send us the parts to replace ourselves, so sending the printer back for repair will most likely be the only option.
Iām pretty sure they would tell me to re-reorient it. Iām pretty sure I should be able to print it with supports and get the same results. Either way Iām pretty sure their solution would just be to keep trying orientations till one comes out acceptable. Iāve been trying to think of a print that canāt be oriented in any way that will mask the flare artifacts, just to be a pain in the ass, but that would also miss the point which is there is noting wrong with the orienation of my print as it is. Everything is more than adequately supported, all overhangs are compleately reasonable angles, the current orientation actually minimizes the surface area for each layer, all upper layers have a sturdy foundation to be built on, and there are adequate openings to allow resin to flow as necessary. You really couldnāt ask for much better of an orientation.
@Monger_Designs to the contrary I think it is the responsibility of support to admit and acknowledge my printer is not behaving as intended. Which it clearly is not. If I have a hard drive go bad on my computer the support guy can admit my drive is not behaving as intended. This does not require the president of the company. If it turns out there is a major flaw in the line of hard drives it may not be the support guys place to admit that, but it is still wrong for him to not acknowledge that my given drive is not behaving as intended. In this case @Stephen is skirting admitting that my printer is not behaving as intended, and is vaguely suggesting the problem is user error instead. If @Stephen is aware my printer is not behaving as intended and not acknowledging so and instead insinuating the problem is user error that is in my opinion borderline amoral. To a less knowledgeable user this could divert them off the path of getting the problem with their printer fixed which could possibly lead to their warranty expiring without having yet gotten it fixed.
As for them checking every other part of the printer first, that strategy seems ridiculous and foolish. Here is a quicker more direct way. Find prints where there are clear artifacts that seem to be of the type we users are attributing to flare. Find a printer that when printing these parts shows these artifacts. Replace the laser with one that does not have any flare, or develop and install one single iris, since this doesnāt have to be the final solution and is just a proof of concept it does not need to be fancy just functional enough to work for a few prints and remove most of the flare. Now reprint the objects if the artifacts are gone or significantly better itās the laser. If I had a group of engineers on hand, who worked 40 hours a week for me, and a giant pile of Form1+'s that I didnāt have to worry about voiding the warranty on Iām pretty sure I could have whether or not itās the laser cleared up in a pretty short period of time.
As a consumer I agree with all you said. Ultimately though, taking responsibility can take many forms. They are not refusing to fix your printer are they?