Receiver Input Lag

[Sparky]

If the receiver doesn't add anything to the video signal, it probably just splits off the data lines for decoding, and passes everything through, instead of re-encoding it. If there's any buffering at all, I suspect it would be limited to single packets.

If it does add something to the video signal, it gets more likely that it would buffer a full frame.

The menu of the receiver is displayed as an overlay over the picture passed through. So it kind of adds something to the video signal. I don't know if it has to buffer the frame to do that.

So there isn't an easy answer, you either have to measure latency with and without the receiver, compare the signal into and out of the receiver with an oscilloscope, or you have to reverse engineer the receiver.

Is there an easy way for a layman to test for input lag?

There are a few methods, the camera method is easiest if you already have a camera capable of ~1k fps, but it's also incredibly tedious if you want any kind of accuracy. Basically you modify a mouse to light up a LED when you click, and count the number of video frames between the LED lighting up and the result on the monitor.

As a second option, It's not too hard to build a latency test device, about ~$50 in parts:
My implementation: viewtopic.php?f=10&t=3005&start=50#p22634
flood's implementation: viewtopic.php?f=10&t=1381&start=310#p23272

A third option is to compare two monitors displaying the same output(a timer) with a still camera, but it sounded like that wasn't working for you.

Fourth option is to buy a leo bodnar tester, and measure latency with and without the receiver.

I think we need a sticky compiling the different latency testing methods.

I simply connected a second monitor to my system and took photos running a stopwatch. While the accuracy is limited by frametime and the online stopwatch I used, it showed a 31 ms difference three times, and a 62 ms difference once. The difference in frame time between receiver and no receiver is not measurable by this method.

There are some tricks to that method, try searching for "SMTT".

[ChiefBigFeather]

Thank you for your help!

My TV seems to be decent in terms of frame times. The difference between v-sync on and off is quite noticeable.

During testing a new problem popped up. I cannot sync to the Blur Busters tests reliably. Chrome/FF both produce the problem and I do have it with the frame skipping and refresh rate tests. Maybe it is a problem with my current drivers?

I'm on win 7, and running an r9 290 on Radeon Software Version 18.2.1.