CurtPalme.com Home Theater Forum

telecine · Joined: 08 Jan 2008 Posts: 23 Location: London

Hi,

I have finally suceeded in getting an output from my HD fury into a BARCO 808 projector on port 3. The source is a Sky HD box running at 720p or 1080i.

How much range of sync adjustment does the crescendo box have?

Even with the H phase of the Barco set to zero, the image on screen is still displaced to the left.

Would this box have sufficient range to sort out this problem? I realise I could raster shift the whole image to compensate, but modifying the sync timings would be a more elegant solution I think.

Does this box also alter the porch timings at all? If so, by how much?

In fact, what are the ranges of all the adjustments?

I'm living in 50Hz hell at the moment as my poech widths are too wide, and Id rather not buy (another) scaler at this point if I can at least minimisethis problem.

All the best.

beun · Joined: 28 Jun 2006 Posts: 676

Telecine,

Since I can only make positive delays, the RTC2x00 can only shift the H-sync into the picture and therefore the picture to the left. This depends however if the projector syncs on the leading edge or the trailing edge. The RTC2x00 can change the width of the sync as well so if the projector locks on the trailing edge that may help. Also the polarity of the sync can be changed which usually causes a picture shift as well.

Kim

telecine · Joined: 08 Jan 2008 Posts: 23 Location: London

Is there any way (by a component change to the circuit) that the overall horizontal sync delay range can be increased still further than the stock unit? Mine seems to give about .75h maximum sync delay. When increasing the maximum delay, would this not enable us to move the picture in either direction? (with a corresponding drop of the whole video image by one line, as the video would be now over one line late with respect to the syncs)?

Interestingly the h phase via port 5 of an 808 is within range at 1080 50i, but if I use port3, even with positive sync which changes the delay by about a sync width, I'm still offset by a couple of microseconds, hence the reason for this post!

I also noticed that with the sync width in automatic, port 5 is happy, but via port 3 the sync width offered by the transcoder is way too narrow to achieve lock (at least on my Barco). On a scope with the transcoder in auto the h sync looks more like a spike than a pulse, but switching to manual stretches out the pulse width sufficiently to achieve lock via port 3.

I did notice the increase in sharpness everyone mentions via port 3, so I'd like to go this way if possible, but I need "less" (ie. more than a line) delay to achieve correct video phase.

Do you think this would work, and if so, is it possible with minor componet changes?

Other than this very minor niggle, I am getting very good results with this box, particularly with a small amount of gamma stretch. Brilliant!

beun · Joined: 28 Jun 2006 Posts: 676

I am planning to increase the H-delay to more than a line. The current design is not capable of doing that as the delay has to be shorter than a line to function. The next redesign of the RTC2200 will have an additional delay option built in so you can in the end perform the left shift.

Kim

telecine · Joined: 08 Jan 2008 Posts: 23 Location: London

Hi Kim,

Thanks for the very fast response. That's good news about the revision to the circuit to increase the h delay. Will this be available as a board swap as per previous upgrades?

I'll be just fine via port 5 for the moment, and I'm enjoying extremely good pictures, but when the new version becomes available, I'll be very interested as I can then use port 3.

Thanks again.