photographing PC monitor and TV screens

[pwas1]

Anyone know the best settings (particularly shutter speeds)to use for taking images of TV or monitor pics as I get moire and other artifacts when trying this?

[Fleshpiston]

I found a good bit of info on this a while back and in short as most TV screens or CRT's run at 60Hz you need to half that to capture it if I remember rightly (long day late night last night). See here for more info:

http://strobist.blogspot.com/2006/04...h-tvs-and.html

[Raycer]

some of the new TVs refresh much faster. with computer monitor you can set the refresh rate to match your shutter speed.
If you set it to 60hz, use 1/60 or slower if the computer monitor is not showing anything in motion. keep in mind your shutter speed will not be exactly 1/60. And I don't think you can go faster then your FP sync speed.

[neverhood311]

I read that the slower your shutter speed, the safer you are. For example, use a 1/30th shutter speed for a monitor that has a refresh rate of 60Hz. Then you're absolutely guaranteed to have at least one full screen refresh and most likely two. Otherwise, as I'm sure you know, if the shutter speed is too fast you'll get a funky-looking monitor.

[Colin Southern]

I read that the slower your shutter speed, the safer you are. For example, use a 1/30th shutter speed for a monitor that has a refresh rate of 60Hz. Then you're absolutely guaranteed to have at least one full screen refresh and most likely two. Otherwise, as I'm sure you know, if the shutter speed is too fast you'll get a funky-looking monitor.

Not necessarily - with PAL they do one scan of odd lines and then the 2nd scan of the even lines - not sure what NTSC does.

[timo2]

Apart from the differences of TV standards such as PAL, NTSC (Never Twice the Same Colour ) and SECAM, TVs and computer monitors have different screen refresh rates.

The refresh rate of a UK PAL TV is 50Hz and PAL is an interlaced system. That means each picture is made of two consecutive scans, one odd, the other even fields. So to get a whole picture you need to shoot at under a 50th of a second, not faster or you will get a bar or black band somewhere on the photo.

In America, the refresh rate of the NTSC TV system is 60Hz, it is also an interlaced system.

Also, some modern digital TVs are progressive scan so again, for best results, you need to check their refresh rate

FWIW the refresh rate of analogue TV systems is linked to the frequency of the mains electricity; 60Hz in America, 50Hz in the UK.

Computer monitors scan at faster rates and they are not interlaced so for best results, you need to find out what the refresh rate of the monitor is and shoot at something just below it.

To avoid moiré, use a wide(ish) aperture and defocus very slightly.

[Ashwin]

Anyone know the best settings (particularly shutter speeds)to use for taking images of TV or monitor pics as I get moire and other artifacts when trying this?

To take Images of Computer Monitor, you can achieve this simply by pressing Ctrl + Print Screen then in photoshop press Ctrl + n to open new window, and paste

[timo2]

That will take a screen shot at the resolution of the monitor. If you want a high resolution image, you need to photograph the screen.

[Ashwin]

That will take a screen shot at the resolution of the monitor. If you want a high resolution image, you need to photograph the screen.

You just increase the resolution of the Image, this way you will get much more better result than directly photographing the screen.You can comfortably get good quality print upto 12" - 18" size

[Dave Humphries]

I have to say I assumed this request was to capture the screen as part of a bigger picture - i.e. of the surroundings.

For just getting something off screen to use elsewhere, Ctrl+PrtScrn (active window), or just PrtScrn (whole desktop including multiple monitors) is the better way to go.

Better still, since even a whole active window can bring too much, which then needs cropping, is the snip tool (if Vista or Win 7).

Even more better still, a third party clip tool - I use Solid Capture as it (via Ctrl+F11) often allows me to grab droplists and tool tips while they're open, which can be helpful when explaining things. Don't think it works on Evaluate version though, I have it at work and it's great there (on XP).

Cheers,

[Raycer]

keep in mind if the TV is showing action at 600 hz, your TV monitor will show 'motion blur' if you use too slow of shutter speed. And finally, is photoshop in the monitor the best idea , just ask BP.
http://www.msnbc.msn.com/id/38333456...ch_and_gadgets

[Fleshpiston]

keep in mind if the TV is showing action at 600 hz, your TV monitor will show 'motion blur' if you use too slow of shutter speed. And finally, is photoshop in the monitor the best idea , just ask BP.
http://www.msnbc.msn.com/id/38333456...ch_and_gadgets

Another slight thing with newer TV (LCD/TFT) screens, is when they state 600hz as some do, they are not actually displaying it as such. They take the "picture" and run it through some chips* and increase the refresh rate that way, but it is not true 600hz.


*chips as in IC's not tattys

Problem with screens is there are a few veriables that make a massive difference.
CRT or LCD/TFT TF/TN Video standards PAL-I NTSC so on so on. I make the things and still have fun with them.

Lets not forget refresh rates H and V can be "programmed" so it all adds to the mix.

My rule of thumb is to use the LCD at the back of your camera or if we are on about screen capture of the desktop then print screen commonly know as Prt Scr key on the keyboard.

[pwas1]

Many thanks to all who took the trouble to answer my query. I did not expect so many replies! I have another query now-I printed out the replies but white text on a black background wastes a lot of black ink-I feel sure there is a simple way of reversing the colour before printing-any of you know what it is?
Once again many thanks,
Regards to all,
pwas1
PS I will try out the methods given and report back.

[Dave Humphries]

I have another query now-I printed out the replies but white text on a black background wastes a lot of black ink-I feel sure there is a simple way of reversing the colour before printing-any of you know what it is?

The exact answer probably depends what web browser you are using, but it sounds like you have the option switched on that prints background/ background colors, you don't want that. If it is off, you should get just the text (in black) on white paper.

Use File > Print Preview to check before you print.

Oh and; Welcome to the CiC forums from ...

[pwas1]

Thanks Dave-I've just discovered that at the bottom left of the page there is a feature "Quick stlyle chooser" and altering this to "light fluid" reverses the colours.
Cheers.
pwas1

[Apo]

Check this out taken from my D90 using Nikkor 28mm
40s f2.8 ISO 1000


Ben Stiller

[Dave Humphries]

Thanks Dave-I've just discovered that at the bottom left of the page there is a feature "Quick stlyle chooser" and altering this to "light fluid" reverses the colours.
Cheers.
pwas1

Yes that will help, but it also confirms my diagnosis that you are printing background colours, which unless you definitely want it, is generally a bad idea.

I would again recommend you look for that check box, or better still, look for the default setting as held in the browser's Options/Preferences dialog and uncheck it.