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 Post subject: Photographing CRTs
PostPosted: Sat Jun 24, 2017 2:51 pm 



Joined: 21 May 2017
Posts: 24
As you might've guessed the exact title should be "photographing CRT live displays", to be more exact. Taking a photo of a switched off TV box itself is fairly straightforward ;)

When it's on, not so much. Due to the nature of the arcane magic powering these things - what I imagine is a mixture of alien death rays, cosmic background radiation and black hole essence - trying to take a perfect pix of a live CRT screen can be fairly tricky. I was wondering if the resident experts might have any advice.

I found two fairly decent articles on the subject:
-http://www.halfhill.com/video.html
-http://strobist.blogspot.co.uk/2006/04/on-assignment-dealing-with-tvs-and.html

So basically the golden rule is "shoot under 1/30". Darken the room as much as possible, avoid reflections. Pray to the Phosphor God.

I tried this (bar the last bit). The results vary, seeing as I don' have a tripod - at this exposure speeds it can be tricky to maintain perfect balance while in handheld mode. Also, I suppose the inherent flickery nature of the medium might play a part. Bu that's a lesser problem, I suppose that with a tripod (or at least a makeshift one) the sharpness can be more less brought under control.

More worrying for me was the fact that white balance is extremely difficult to reproduce properly. Basically, the colours you get in the photo seldom match the ones on screen. Not sure how to deal with this (tried lots of different mods, custom one sometimes help). You can of course try and compensate in some post processing program, but that's more of a hassle, especially seeing as you then need to fire up the game and find the particular scene to compare.

I'm using Sony RX100. Mostly tried with shutter at 1/15, f stops depending on the scene (mostly 2-5) and ISO 200. The TV is KV-29F2U Trinitron (contrast: near max, brightness: about 1/3rd) fed RGB signal from RPi3 B.

Some examples (click for the big ones)

ImageImageImageImageImageImageImage

Any suggestions on how to improve the results most appreciated. I'm mostly concerned with sharpness & colour reproduction, geometry/framing is more of a "mechanical", easy issue (similarly, these haven't been retouched with usual post process tools).


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 Post subject: Re: Photographing CRTs
PostPosted: Thu Jan 04, 2018 2:27 pm 



Joined: 16 May 2017
Posts: 61
Location: London, England
I’d be interested too.

How do you find that CRT for gaming by the way? Sharp?


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 Post subject: Re: Photographing CRTs
PostPosted: Thu Jan 04, 2018 3:26 pm 



Joined: 26 Jan 2017
Posts: 24
I don't have much advice for shutter speeds and ISO and stuff. Some cameras do offer the ability to adjust white balance--mine does and I just toy with white balance until the LCD matched what I was seeing in real life.

But I do recommend a tripod...those scanlines need to look nice as possible!

Actually, I have the same camera as you (pretty sure...). There is an in camera setting for Custom white balance where you can move an icon across the color balance to get differing temps.


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 Post subject: Re: Photographing CRTs
PostPosted: Fri Jan 05, 2018 3:45 am 


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Joined: 16 Jan 2014
Posts: 646
A few shots of my 27" Sony Trinitron Wega I took a few years ago. Used a tripod and a Fuji 3MP camera. A sharp input /source makes a big difference too.

https://imgur.com/a/0FxFF


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 Post subject: Re: Photographing CRTs
PostPosted: Fri Jan 05, 2018 6:02 am 


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Joined: 04 Nov 2005
Posts: 978
Location: Brisbane, Australia
dreadnought wrote:
avoid reflections.

Back in the 80s and 90s, they used to have a makeshift squarish cardboard cone of sorts that they'd use to eliminate reflections. I tried to find a few shots of it, but nothing turned up in a quick Google search.

It would also help center the shot, and ensure the exact distance from the screen each time.
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 Post subject: Re: Photographing CRTs
PostPosted: Fri Jan 05, 2018 2:16 pm 



Joined: 10 May 2015
Posts: 395
Location: Stockholm, Sweden
I'm only using DSLRs for all my photographing. I'd say match the shutter with your refresh rate. For focal lenght, use a normal lens or longer (avoid wide-angle and fisheye). Screen sizes at 20" or higher I prefer to have a larger aperture (3.5-4.5 is usually enough) while smaller CRTs benefit from using a smaller aperture. Automatic focus may work somewhat but manual is recommended to avoid moire. Set the ISO so you get a somewhat bright picture but not too noisy. Set white balance at either 5600° or 6500° Kelvin, otherwise you'll lose too much color.

There are no rules of thumb when photographing CRTs. You have to experience it yourself and get good in order to make decisions for your shots. The suggestions above are mainly for 15KHz. CRTs with higher line frequency are much more difficult to capture.

I'd say avoid kit lenses. Primes are much better when you're on a budget. If you really want to play around I suggest getting a macro lens. The Nikkor 40mm/2.8G (APS-C) is fantastic for its price tag.


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 Post subject: Re: Photographing CRTs
PostPosted: Tue Jun 04, 2019 7:45 am 



Joined: 04 Jun 2019
Posts: 1
Hi, do you still have you're f2u ? I have one myself and is there an art to getting any audio out of it in the menus ? I have the 2 correct stereo speakers attached which do work as I can get the test tone from the f2u. Tv is def not on mute and I can't get any audio at all . Tried both and MD and Saturn via the rgb av1 input and nothing :-/ . Thought you might know something I don't .


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 Post subject: Re: Photographing CRTs
PostPosted: Sun Jun 09, 2019 7:53 pm 



Joined: 04 Apr 2014
Posts: 638
nissling wrote:
I'm only using DSLRs for all my photographing. I'd say match the shutter with your refresh rate. For focal lenght, use a normal lens or longer (avoid wide-angle and fisheye). Screen sizes at 20" or higher I prefer to have a larger aperture (3.5-4.5 is usually enough) while smaller CRTs benefit from using a smaller aperture. Automatic focus may work somewhat but manual is recommended to avoid moire. Set the ISO so you get a somewhat bright picture but not too noisy. Set white balance at either 5600° or 6500° Kelvin, otherwise you'll lose too much color.

There are no rules of thumb when photographing CRTs. You have to experience it yourself and get good in order to make decisions for your shots. The suggestions above are mainly for 15KHz. CRTs with higher line frequency are much more difficult to capture.

I'd say avoid kit lenses. Primes are much better when you're on a budget. If you really want to play around I suggest getting a macro lens. The Nikkor 40mm/2.8G (APS-C) is fantastic for its price tag.

These are some great tips.


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