DenKor wrote: ↑13 May 2019, 10:01
Hello! I have LG PF1500G (06/2018). Minimum focal length is 29cm with 21*12cm pictures size.
If I need to reduce the focal length, I can use lenses in front of the projector (Macro Close Up Lens filter +1+2+4+10 for Nikon from aliexpress). For example with a +2 lens, I can get 20cm focal length with 15*8.5cm picture size.
photo_2019-05-13_13-00-49.jpg
I tried those macro lenses on my pf1500 too but found they introduced too much distortion to be useful. The error in calibration when way above acceptable values. What types of RMS values are you getting after calibrating with one of those lenses? Even still I found the 52mm adapter ring I mounted to the projector lens to be very useful for adding ND filters for scanning small objects. I like running the projector brightness in David at at least 200 as to have some range to dim and brighten during scanning to reduce hot spots.
I ordered a new camera on a chip imx265 and new 12 mm 5mpx c-mount lens and I'll try with them when they come. after the experiments will tell you the results.
In Russia, one person tried these lenses in front of the projector to scan coins.
DenKor wrote: ↑13 May 2019, 10:01
Hello! I have LG PF1500G (06/2018). Minimum focal length is 29cm with 21*12cm pictures size.
If I need to reduce the focal length, I can use lenses in front of the projector (Macro Close Up Lens filter +1+2+4+10 for Nikon from aliexpress). For example with a +2 lens, I can get 20cm focal length with 15*8.5cm picture size.
photo_2019-05-13_13-00-49.jpg
I tried those macro lenses on my pf1500 too but found they introduced too much distortion to be useful. The error in calibration when way above acceptable values. What types of RMS values are you getting after calibrating with one of those lenses? Even still I found the 52mm adapter ring I mounted to the projector lens to be very useful for adding ND filters for scanning small objects. I like running the projector brightness in David at at least 200 as to have some range to dim and brighten during scanning to reduce hot spots.
I ordered a new camera on a chip imx265 and new 12 mm 5mpx c-mount lens and I'll try with them when they come. after the experiments will tell you the results.
In Russia, one person tried these lenses in front of the projector to scan coins.
CBDC081C-A1CF-41CA-BAE9-6D2836277203 (1).png
That's very good detail. Where the problems show up is when you try to align multiple scans. you will see that they don't completely align, with edges being more of a problem. Keep us posted.
did anybody tried it, or know if it's square pixels?
When I was researching projectors I was able to find specifications regarding DLP DMD orientation, however is seems that most DMD chip makers are going with the diamond pattern as it allows for smoother gradients and dithering which are advantages in home projectors showing movies. That said I also when to a couple of local retailers (Im in NYC so there are a few show rooms) and actually when through their display units and looked at the DMD pattern and the focal distances. The LG was the best compromise in an HD projector at the time. We've been wanting to replace the LCD TV in the living room with a projector for a while and I have been thinking at looking into some of the new 4K offerings. If I find anything good I'll post. In the meantime perhaps you can find a PF1500 on ebay? The square pattern helps, but I don't think it is worth killing your self to find. If you can order from Amazon, Newegg, or B&H you can try a number of projectors and return them if they don't suit your needs.
DenKor wrote: ↑13 May 2019, 10:01
Hello! I have LG PF1500G (06/2018). Minimum focal length is 29cm with 21*12cm pictures size.
If I need to reduce the focal length, I can use lenses in front of the projector (Macro Close Up Lens filter +1+2+4+10 for Nikon from aliexpress). For example with a +2 lens, I can get 20cm focal length with 15*8.5cm picture size.
photo_2019-05-13_13-00-49.jpg
How do you fit the lens ? do you have reference numbers i can look them up ?
I just purchased same projector and i would like to try
Thanks
I am fixing them with adhesive tape, but this is not a successful solution. In the future I will print on the 3D printer a normal mount.
To my shame i still haven't checked RMS with this lens.