Cat and Mitsubishi DLP

[jeyurkon]

I guess this isn't vintage being slightly less than a year old.

One of my cats enjoyed watching certain shows on the 60C9 DLP. The rest of the time he would ignore it. About a week ago he suddenly looked at the set like it was going to attack him. He paced back and forth looking at the screen and eventually ran past it out of the room cowering.

He still does this sometimes, and only when he's looking at it. The DLP had started flashing blank for a fraction of a second every once in awhile, but I decided that it was the DirectV receiver. It didn't do it on over the air programming. That started at the same time as the cat, Schatzi, started getting upset about it.

I can't figure out what he's seeing. It looks the same to me, but he watches something moving on the screen even on still scenes. I don't think it's sound because he only acts this way if he happens to look at the screen.

John

[ha1156w]

If it's a DLP with a color wheel, I'd have to wonder if the color wheel motor or its mechanism wasn't making some sort of noise that tripped out the cat. That would also explain the blanking of the screen you report -- it could be the color wheel resyncing.

[Adam]

I often see these sort of color flashes on dlp sets or projectors, it really bothers me, but I've never found anyone else that seems to see it. Maybe the cats see the same?

[matt_s78mn]

I don't think its the TV. We have a DirecTV receiver connected to an LCD flat panel at work that blinks momentarily once in a while like you've described. I've got two different DLP sets (a Sanyo 55" and Mitsubishi 62") and a Samsung plasma at home all connected to Dish Network and I've never seen that happen.

Its funny though, my cat will sit there and stare at the screen for hours! Sometimes she will even paw at the screen.

[jeyurkon]

Originally Posted by ha1156w

If it's a DLP with a color wheel, I'd have to wonder if the color wheel motor or its mechanism wasn't making some sort of noise that tripped out the cat. That would also explain the blanking of the screen you report -- it could be the color wheel resyncing.

I've also started to hear the color wheel during the start of its spin up. I don't hear it while it's running, but maybe Schatzi does.

Originally Posted by Adam

I often see these sort of color flashes on dlp sets or projectors, it really bothers me, but I've never found anyone else that seems to see it. Maybe the cats see the same?

It thought this was a solved problem, or maybe you have cat like vision.

Originally Posted by matt_s78mn

I don't think its the TV. We have a DirecTV receiver connected to an LCD flat panel at work that blinks momentarily once in a while like you've described. I've got two different DLP sets (a Sanyo 55" and Mitsubishi 62") and a Samsung plasma at home all connected to Dish Network and I've never seen that happen.

Its funny though, my cat will sit there and stare at the screen for hours! Sometimes she will even paw at the screen.

He used to watch it from his cat tree. But mostly when he's bored.

John

[wa2ise]

Cats can hear higher frequencies than we can, and their eyes have different color response. Their eye's persistence is likely different than ours. Turns out humans have very good color vision compared to most animals, IIRC cats can only tell yellow from blue. TV sets only produce red, green and blue, and when we see yellow on a color TV, it's really a mix of red and green, and it tricks our eyes and brains into thinking the eyes are seeing yellow. Cats' vision may not be tricked the same way, and your cat may be getting bothered by the color wheel not syncing right.

[ChrisW6ATV]

Originally Posted by Adam

I often see these sort of color flashes on dlp sets or projectors, it really bothers me, but I've never found anyone else that seems to see it. Maybe the cats see the same?

This is a long-known issue with some people and DLP display devices, probably more with front projectors than with rear-projection (all-in-one-box) TV sets. The phenomenon is called "rainbows", and it is because all but super-expensive DLP projectors use one image panel that shows one color's data at a time, along with a color wheel to filter the light reflected off the image device. It essentially works just like the CBS color system from the early 1950's, except at multiples of the typical 60 Hz USA screen refresh rate. It is possible to teach almost anyone how to see the rainbows, but I won't do that here because it could cause people to be bothered that otherwise would never have noticed. I have had two DLP projectors and learned how to see them, but it didn't bother me.

[jeyurkon]

Originally Posted by wa2ise

Cats can hear higher frequencies than we can, and their eyes have different color response. Their eye's persistence is likely different than ours. Turns out humans have very good color vision compared to most animals, IIRC cats can only tell yellow from blue. TV sets only produce red, green and blue, and when we see yellow on a color TV, it's really a mix of red and green, and it tricks our eyes and brains into thinking the eyes are seeing yellow. Cats' vision may not be tricked the same way, and your cat may be getting bothered by the color wheel not syncing right.

Cats are amazing and I'm sure you're correct in that they can see short time scale phenomenon that we can't. They look goofy when they're play fighting, it's so slow it looks like tai chi. But when they do it for real it's all a blur.

The 60C9 actually uses six different color segments and yellow is one of the ones that it produces without mixing.

Originally Posted by ChrisW6ATV

This is a long-known issue with some people and DLP display devices, probably more with front projectors than with rear-projection (all-in-one-box) TV sets. The phenomenon is called "rainbows", and it is because all but super-expensive DLP projectors use one image panel that shows one color's data at a time, along with a color wheel to filter the light reflected off the image device. It essentially works just like the CBS color system from the early 1950's, except at multiples of the typical 60 Hz USA screen refresh rate. It is possible to teach almost anyone how to see the rainbows, but I won't do that here because it could cause people to be bothered that otherwise would never have noticed. I have had two DLP projectors and learned how to see them, but it didn't bother me.

I can see the rainbow effect in front projectors at work, if I try. But I haven't been able to see it in the Mitsubishi. That's not to say that the cats can't see it. The Mitsubishi has six color segments. They don't say the wheel speed but their similar models are 10,800 RPMs which would be a frame rate of 180 HZ. If you can see a rainbow in that you have really fast eyes.

But, the point is that it didn't bother Schatzi for almost a year even though he did watch birds and other interesting things. It's only recently that he started responding so strongly to it. Angel is also starting to react to it. If it was simply the rainbow effect then they should have seen it in the beginning.

I checked the number of hours on the lamp and it's 3,500 so far. I wonder if it's starting to flicker. Can they do that before they die?

John