Hello

I recently bought a Dreambee 1.
For better peformance i want to measure grayscale, gamma and RGB levels.
My screensize is 110" wide with gainfactor 1. As player i use a PS3.
Patterndisk is Blueray DVE Video Essentials.
My room is a dedicated home theater complete dark.

My desired hardware is EyeOne Display 2 and HCFR.
I followed the guide at Curtpalme.

As you know the Dreambee 1 has no colormanagement and possibilities to change
the gamma curve. So i adjusted the RGB Level at 50IRE.
The inital brightness in normal lamp mode at 100IRE is 8,6 ftl.
My first question is that possible ??
In press you can read the gamma is close to 2,2.
Please take a look at my graphs. The average value is 1,8

Are my measurements ok or is something wrong? I can´t believe that
the gamma is far away from norm. Please get me some comments or maybe
other JVC RS1 or Dreambee owners can post their values.

RGB Level
http://bloodvalley.com/2.jpg
Gamma
http://bloodvalley.com/3.jpg
Luminance
http://bloodvalley.com/4.jpg
CIE
http://bloodvalley.com/1.jpg

Greetings

Are you sure you set the brightness and contrast correctly? (Just because you have the disc does not mean you set it right.)

If you take color saturation down ... the triangle should start to shrink ... try -15 and see where it ends up.

Take the contrast down 5 clicks and see where the gamma ends up then ... then another 5 clicks ... and so forth.

Regards

In my experience 1.9-2 for gamma is typical for the RS1- talking about the previous model without the gamma adjustments.
The 8.6 footlamberts sounds approximately right for a large 1 gain screen such as yours, though I use the Eye one pro meter, which can make a small difference in the reading. My feeling is that if you have a large screen with this PJ some screen gain is a good thing. One RS1 that I calibrated was on a Da-Lite High Power screen (going by memory I believe it was a bit smaller than yours), and on that screen I got 28 ftl in low power mode. This screen is rated at 2.8 gain, and many on the forum suggest it is closer to 3. If you factor in that it was slightly smaller than yours, and the possible differences in lamps and meters, your reading is not surprising. The customer was happy because he likes alot of light output.

Thx for your reply.
@Michael
At the weekend i will try what you suggested. Maybe i can get better results.
@Chad
According to your experience i guess my readings are ok.
Maybe i should buy a better screen with at least 1.5 gain.

Hi,

Just a point about turning the colour down so that the CIE triangle shrinks in size. I did this initially and ended up with a very under saturated picture and very poor Delta E results.

Setting the colour control up using the method of Red 21% of white worked very well, giving me very good Delta E results and a better saturated picture. However, this left my Gamut chart still slightly wider than normal.

Other members in this forum have stated that the color control only affects the brightness of the colour and not the saturation. To correctly shrink the triangle you would require a colour management system.

Please correct me if I am wrong, but this is the information I think I have interpreted from other forum members.

Greetings

Here's some more points for you. :)

The image starts out over saturated ... so if you reduce the color, you will of course de-saturate the color. If you have all the correct gear, you still end up desaturating the color to get there.

Without the right controls, you are only trading one set of wrong numbers for another set of wrong numbers. They are still wrong either way because you don't have the right controls.

Lastly, your calculator is not designed to work right with this technology so it won't give you the right answers anyway. :D It should not be used for doing stuff like color management. You need a spectrometer to do it right.

I've worked on plenty of these units and while taking the color saturation down does reduce saturation ... (what it's supposed to do) ... whether it is truly undersaturated in a negative way would depend on the original position actually being correct in the first place to make a valid comparison. (it's not correct)

Bottom line ... play with it ... see what you get. It's not worth dying over ... but if you want more accurate results, you need more expensive gear.

Regards

My desired hardware is EyeOne Display 2 and HCFR.
I followed the guide at Curtpalme.

Snecx,

you may want to post your chc file so folks can look at all of the measurement numbers (there is a separate thread for doing this as well). The CIE diagram only shows part of the story with regard to color for example.

cheers,


--tom

Snecx,

you may want to post your chc file so folks can look at all of the measurement numbers (there is a separate thread for doing this as well). The CIE diagram only shows part of the story with regard to color for example.

cheers,

did it ... :) :)
thx for the hint.