CurtPalme.com Home Theater Forum

userxyz · Guest

Hello,

with HDfury it is possible to send HD Signals like 720p, 1080i or 1080p including HDCP to a CRT Computer Monitor which has VGA or BNC input and is capable of receiving and displaying these resolutions.

But:

Wouldn't it be hurting for your eyes when watching a signal with a refresh rate of 60 Hz, like PS3 Games, on that kind of display?

Technologies like LCD, Plasma, DLP and so on, don't have this problem.

A CRT Computer Monitor with less than 85 Hz input always is flickering very much, which should be bad for your eyes. At least if you are sitting right in front of it, like you would at your desk.

Does someone have some experience with that?

And is it possible to increase the refresh rate with an external device, as this is not possible with a HD device like the PS3?

If yes, would this affect the image quality in terms of sharpness and so on? And would it produce lag, tearing or something like that?

What device do you have to use for something like this? And how much could you increase the refresh rate?

It is no question, that you can not increase the actual game fps or the refresh rate that comes from a console with such an external device, but maybe you can increase the refresh rate you are putting out to the monitor.

When you play games on PC, and a game does run at 30 fps you are still able to run the monitor at 85 Hz or more or less, too.

Actually some people use their PS3 and Xbox 360 with a CRT Computer Monitor, using a HDfury or direct VGA output from Xbox 360 with a VGA cable for Xbox 360.

It would be nice to know if someone knows how bad the flickering is, as it is usually too bad for your eyes at 60 Hz refresh rate from a PC ouput on this kind of display.

If there is a solution to increase the refresh rate with an external device it would be good if someone could explain this, too.

Thank you in advance.

Gino · Posted: Sat Mar 29, 2008 11:50 am Post subject:

I'm sure most people using CRT front projectors are likely running at 60Hz without issue. Those who find flicker a problem can try running at 72Hz or 96z. I personally find that if the signal is progressive rather than interlaced, I can watch things at 50Hz without issue.

You can use external video processors for increasing frame rates from sources like a PS3.

The processing shouldn't really make image quality worse. Running higher refresh rates will require greater bandwidth, so you do push the CRTs more, and if they aren't up to the task your image will suffer, for example softness. Depending on the type of processing you are performing you can get lag, but the better video processors have different modes to reduce the amount of lag.

Try: www.dvdo.com, www.lumagen.com for the more popular video processors

userxyz · Guest

Thank you for your reply.

But the question was about CRT Computer Monitors not CRT front projectors.

They are usually flickering very much at 60 Hz from a PC output, which is not good four your eyes, especially when you sit right in front of it.

The question is, how bad is it when connecting a PS3 or any other HD device, which will always output a maximum refresh rate of 60 Hz with a HDfury, compared to the situation above.

Yes, the pictures often gets softer on that kind of display when you increase the refresh rate. But this shouldn't be the biggest problem, as most PS3 games only display in 720p. Most CRT Computer Monitors should be able to display at a higher refresh rate than 60 Hz with a resolution of 1280 x 720.

And yes, maybe there is no problem with low refresh rates on CRT front projectors.

Usually standard CRT TV Devices are okay, too, although they only receive 50 or 60 Hz interlaced signals.

Furthermore you are not sitting right in front of them, like you would do with a CRT Computermonitor.

But CRT Monitors just flicker much more with 60 Hz progressive signals than a CRT front projector or CRT standard TV would do.

And, yes, maybe some of the CRT front projector users are just able to increse the refresh rate to 72 or 96 Hz because they are using a PC to output their content. But this isn't possible with a standard HD device like PS3, as HD resolutions have a maximum refresh rate of 60 Hz, which is not changeable in the device itself.

When you would use a video processor as a possible solution, you would always have to feed the CRT Computer Monitor with a refresh rate, that is fitting the HD device output, wouldn't you?

Like for example, when a HD device outputs 60 Hz, the next increased refresh rate, coming from the video processor, has to be 120 Hz, hasn't it?

Or for another example let's take 24 Hz.

The PS3 would have to output 24 Hz and the video processor would have to output 72, 96 or 120 Hz, wouldn't it?

How would the image be affected when using 90 Hz with the video processor for example when the HD device is outputting 60 Hz?

Still, are there some people that have some experience with connecting a HD device directly with a HDfury to a CRT Computer Monitor?

Is it actually playable and watchable at 60 Hz in terms of eye hurting and so on? Or is it nothing more than just cool to see, that it is possoble to connect a HDMI HDCP device to such a display?

The picture shouldn't be bad for sure, that is not the question.

The question is the 60 Hz problem you would have when you are sitting in front of a CRT Computer Monitor and putting out a signal from your PC with 60 Hz refresh rate. But this time with a HD device.

**kal** · Posted: Sat Mar 29, 2008 1:18 pm Post subject:

userxyz · Guest

ecrabb · Posted: Sat Mar 29, 2008 4:16 pm Post subject:

It's also a matter of the specific content you're looking at, how you concentrate on it, and the contrast within the image itself. When you're looking at bright white in Word docs or Excel spreadsheets, 60hz flicker is WAY worse than if you're playing a dark game or something. You don't watch video the way you concentrate on areas of the screen like you do when you're using a computer.

In short, I've watched a fair amount of HD content on a desktop CRT monitor - usually at 1080i - and I've never had any objection to it like I would have running the computer display at 60hz. Of course, 1080i is 60hz interlaced - 60 FIELDS per second - which doesn't flicker the same way 60p does.

I'd also have to quibble with this statement a bit:

userxyz · Guest

Hello,

thank you for your reply.

Yes, this was, what was meant. If you can stand the 60 Hz flicker better when only playing PS3 or Xbox 360 games or watching TV or movies and not actually working with it.

You said something about 1080i and 1080p with 60 Hz over a HDfury on a CRT Computer Monitor.

You mentioned something about a difference in flicker.

So would one of the resolutions flicker more than the other on a CRT Computer Monitor over a HDfury?

Which one does flicker more and why?

And is the image quality of 1080i worse than 1080p on a Computer CRT Monitor directly fed by a HD devive over a HDfury?

Can you actually feed such CRT Computer Monitors with interlaced signals?

What about 720p? How would the flicker be there?

Yes, one chip DLP projectors can have RBE which is bad for some people.

With technologies like LCD, Plasma, DLP and so on, don't have this problem was meant, that especially LCD Monitors are much better to look at when fed with a 60 Hz signal from PC output compared to a CRT Computer Monitor fed with a 60 Hz signal from PC output because your eyes won't hurt and there is no noticable flicker.

And you only have a maximum of 60 Hz from a HDfury, as all HD sources will output a maximum of 60 Hz.

But CRT Computer Monitors should actually be good to play PS3 games on it, as they are faster than LCD and there is no interpolation like on the most LCD and Plasma Screens when feeding them with 720p for example.

If there wouldn't be this 60 Hz flicker problem.

Yes, everyone is more or less sensitive in such things, but to sit right in front of a CRT Computer Monitor with a refresh rate of 60 Hz from a PC output is hard to bear.

Therefore the questions.

**kal** · Posted: Sat Mar 29, 2008 5:20 pm Post subject:

Resolution has nothing to do with how bad or good the flicker is - it's 100% dependant on the refresh rate.

The HDfury does not make the flicker any worse or better. It simply converts HDMI/DVI to analog RGB. If you feed it a 60Hz digital signal, the HDfury will output a 60Hz analog signal.

You do not have a maximum of 60Hz from the HDfury. If you feed the HDfury a higher refresh rate it'll work as well. The problem is as you stated, most sources (not just HD) only output 60Hz. That's where video processors come in like ones from Lumagen and DVDO. They can take the signal and convert it to any resolution/refresh rate you like/

I'm not entirely sure why this topic is in the HDfury forum however as 60Hz flicker it has absolutely nothing to do with the HDfury.

Kal

userxyz · Guest

Thank you for your reply.

The question was what you meant with the difference in flicker between 1080i and 1080p.

In other words, interlaced and progressive resolutions because you mentioned something like that.

Can you explain it?

Where would be the difference in flicker on such a monitor when you compare interlaced and progressive resolutions directly fed into the display?

Is it possible at all to send 1080i directly to such a monitor?

And yes, as mentioned before, the 60 Hz limit is coming from the sources, not from a HDfury itself.

As the application of putting a HDMI HDCP signal to a standard CRT Computer Monitor becomes available through a HDfury, this question was put into this forum because some of you people maybe could already have some practical experience with such a connection and tell something about it.

**kal** · Posted: Sun Mar 30, 2008 12:13 am Post subject:

I've moved this topic to the CRT Projectors forum where it'll get seen more and while the topic's about CRT monitors, there's no CRT monitors forum here.

Kal

kschmit2 · Posted: Sun Mar 30, 2008 9:50 am Post subject:

the only things the flickering can cause are fatigue (eye muscles), or in extreme cases nausea.

Both of these are temporary effects only, with no lasting consequences.

**AnalogRocks** · Posted: Thu Apr 03, 2008 2:22 am Post subject:

**AnalogRocks** · Posted: Thu Apr 03, 2008 2:25 am Post subject:

I've run the HDFury into a Sony G520 21" CRT monitor recently at 1080i and 1080P I used 60Hz and 72Hz. Both looked ok.

I didn't notice a flicker at 60Hz and belive me I can see it. I see it in flourescent bulbs and those new useless compact flouresent bulbs too. So I can see it. 'crab's right. It's much worse on a full white page then it is on a movie.