Optoma HD50 2D Calibration.
I always look briefly at the uncalibrated settings on any projector i view just to see how it performs, i think your average viewer who is not into calibration would happily watch this projector in an uncalibrated state, just making a few changes to the brightness, contrast and sharpness settings can improve the image immensely, for calibration of this projector i will be using Spears and Munsil 2nd Edition, a Chromapure calibration disc and computer software, a high quality tripod and an i1 Display Pro 3 Colorimeter.
I found setting my Oppo blu ray player to output RGB Video Levels gives more accurate colour calibration.
I now have 150 Hrs on the bulb, at this point i have set the projector to Reference mode, Auto Colourspace, D65 HDTV colour temperature and a Film Gamma curve of 2.4. I always set the brightness and contrast so that they pass white and colour clipping tests and the ramps in the middle are set so that artifacts are not being introduced into the image, also to make sure that brightness is not clipping shadow detail. The sharpness control is set so that edge halo’s are not an issue and the image will not appear harsh and unnatural. I make sure brilliant colour is at 1, i do various tests using the Spears and Munsil disc before and after calibration, at this point Greyscale is still uncalibrated, here is an image showing you what to expect.
As you can see there is too much green in the image and not enough blue or red, this should be easy to fix using the Optoma HD50’s two point white balance controls. One thing to bear in mind is to calibrate after allowing the projector time to warm up and with the dynamic black feature off or it will interfere with your calibration.
After fifteen minutes of tinkering with the controls i am able to get a very good greyscale reading. I use a 75% pattern at 100% saturation and calibrate to full Rec. 709 standard, i then re-check at all levels.
After adjusting greyscale i always check the gamma curve, you can see the results for gamma in the top part of the above image, be aware that even one click up or down on contrast can change the gamma curve and of course the greyscale so it’s always worth experimenting with greyscale to get the curve you wish, you can also see i have chosen 16ft lambert for brightness levels, i personally like anywhere between 14ft lambert and 16ft lambert, i find anything higher can cause eyestrain in a light controlled environment, at least after a few hours of viewing movie content, if you have light in your own room then by all means go brighter.
Now it was time to calibrate the colours, the uncalibrated colours were not too bad with red being the best with a delta error of 2.8, the lightness and saturation were very good and only the hue was off by a considerable margin, the worst colour was cyan with a delta error of 9.7 this was closely followed by blue, the CMS in the Optoma HD50 allows us to correct hue, saturation and lightness errors, since this projector uses an RGBRGB colour wheel i expected to be able to calibrate it with ease and get great results.
As it turns out i found it harder to calibrate than the Optoma 131xe projector which uses an RGBCYM colour wheel, i managed to get all the colours looking very good although cyan was a lot more frustrating and proved the most difficult, in the end there was a slight undersaturation in cyan, see the results in the image below.
After any projector calibration you do need to check all the settings again, to this end i always check brightness, contrast, sharpness, greyscale, gamma and colour decoding and luminance and check the settings in the CMS again at 100%, 75%, 50% and 25% levels, i usually find with DLP projectors that the 100%, 75% and 50% levels remain very good but a slight dip in performance at 25% levels and the Optoma HD50 was no different although i felt the delta errors were still acceptable at 25%, hue remained good but saturation was down and lightness was up, especially on blue, i saw no huge issues while viewing actual content.
Click here for the Optoma HD50 3D calibration section.