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Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
hboy007 wrote ...
just found this
did you filter the x-rays, e.g. with an aluminium plate in front of the tube?
just now i added single side pcb for that (its copper, so don't need to be that thick) first test doesn't have any filtering i found Exxim Cobra reconstruction software it works very nice for samples, but i can't figure out input for mat for this program success
Registered Member #3271
Joined: Mon Oct 04 2010, 02:29AM
Location: Canada
Posts: 159
Thanks for posting the info. I noted on the top righthand field of the download page that there is a program to convert user pix to the cobra format or is your issue different? I'll give the program a trial. Looks pretty good from the website. Any ideas about cost? Looks like the only restrictions are about filter algorithms and watermarks so I should be able to give it a good trial.
Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
richnormand wrote ...
I noted on the top righthand field of the download page that there is a program to convert user pix to the cobra format or is your issue different? I'll give the program a trial. Looks pretty good from the website.
Well, demo is very annoying. after one second, its start to blink demo demo demo, in random places, also where is watermark EXXIM in reconstruction. i was unable to use converter, it make blank output. what's helped is that MatLab can make from tif to dicom format, and that what i was using in reconstruction i hope i can use slice to reconstruct final 3D , but again, format is not understandable to lot of programs.
Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
Here is mistake that i did: ok, first i was using 3.2s exp time and added another one second for x ray source to warm up each time. and i boosted power to 500W or so . after 50 cycles MSP430 crashed, program stopped ( first time, maybe from radiation i don't know, never had that problem before). But that was good thing. after turning all my stuff off, i found out that tube was overheating ( my housing was just at melting point ). so now i will add filters for radiation, boost power once more, but i will swap cameras to canon 30D and going to use 1.8 lens with 1600iso, so i don't have to keep power for 4.2 secons, but i will have same images at 0,2-0,5s exp time. for compare, now: 5MP 2,8 80 iso 3,2 exp time 5MP 1.8 1600iso 0,4 exp time Also i redesigned cooling system, so after some time because of heat my power level is very stable, ( last time it dropped from 400W to 200W because of heat in smps, and flyback's ( and x-ray tube ?? ))
so now for reconstruction is used 512x512 pixels photos (2x more than first one), and it possible to see copper tracks inside mouse :)
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HomeMade CT [update_first _3D_pictures]
