AVS Forum banner

21 - 33 of 33 Posts

·
Registered
Joined
·
5,324 Posts
Question for those more knowledgeable than myself: would the SPD of the display also affect the accuracy of any measurement taken by a camera?
Possibly. The sensor works in the same way as those in a colorimeter but AFAIK doesn't have the filters a colorimeter does. Its response shaping is done via software in the camera.
 

·
Registered
Joined
·
713 Posts
Question for those more knowledgeable than myself: would the SPD of the display also affect the accuracy of any measurement taken by a camera?

I would assume not, with current technology displays. The pixels emit light until they are told not to. They don't have a darkening period or refresh like CRTs did. I wouldn't go for a quick shutter speed on the camera tho, I'd prioritize low ISO.
 

·
Registered
Joined
·
5,324 Posts
I would assume not, with current technology displays. The pixels emit light until they are told not to. They don't have a darkening period or refresh like CRTs did. I wouldn't go for a quick shutter speed on the camera tho, I'd prioritize low ISO.
I believe he meant Spectral Power Distribution, which shutter speed really wouldn't affect...
 

·
Registered
Joined
·
1,751 Posts
I believe he meant Spectral Power Distribution, which shutter speed really wouldn't affect...
yes exactly. Ok, what you said above was roughly where my thinking was.
 

·
Registered
Joined
·
910 Posts
I feel like I have to chime in here. This is not "calibration". Eyeballing is not calibration either. I wouldn't go and shout out to the hills that you've discovered a new way to calibrate your TV. What you are trying to achieve is pointless. No matter how much logic you think is involved in the process using lights, DSLR camera, cell phone camera, whitebalance settings etc. You can't get an accurate image this way. Sorry but this is reality.
 

·
Registered
Joined
·
45 Posts
Discussion Starter #27
I feel like I have to chime in here. This is not "calibration". Eyeballing is not calibration either. I wouldn't go and shout out to the hills that you've discovered a new way to calibrate your TV. What you are trying to achieve is pointless. No matter how much logic you think is involved in the process using lights, DSLR camera, cell phone camera, whitebalance settings etc. You can't get an accurate image this way. Sorry but this is reality.
Thanks for the contribution, your highly technical explanation of why this isn't "calibration" is helpful to the body of knowledge in the thread.
 

·
Registered
Joined
·
45 Posts
Discussion Starter #30
@agd do you have before and after pics of what the TV looks like? I'd be curious to see the difference.
@Dan DaSilva Sorry for the delay, life got in the way.

I reset everything to default, set 2 point, 10 point, taking before and after pics along the way. DSLR was set to manual white balance (6500k), manual exposure, raw, natural color profile, 100 iso-- exif attached (removed artist/serial info, yall don't need to know me). Took it into and straight out of lightroom with no adjustments, just jpg conversion.

Seeing the before and after 100% confirms what I was seeing, default warm2 with no other adjustments looks poor. After calibration, even two point, has it looking outstanding. I don't know what it would look like calman calibrated, but after my experience staring at screens for my photography I can say my tv finally looks 'right' to me now.

I have the raws so I can bump the exposure if it's too dark, but I didn't want to do any post processing so it's as genuine as possible.


Default:
https://imgur.com/GFg1YJ4

10 point, exact same camera settings, manual white balance, zero change between the two:
https://imgur.com/oruhLae

2 point, I messed up (sorry yall), shutter setting was different, but white balance and every other setting except shutter was the same:
https://imgur.com/jHeMg4f
 

Attachments

·
Registered
Joined
·
186 Posts
I like this discussion and have a question. How do you use the white calibration mode with color grab. I cannot quite understand it. I have a 6500K lamp and a calibration white card. I put the app in the white calibrate mode and point it at the card. And it seems to self adjust to that. But now what do I do?
do I switch back to normal and take grayscale readings, or do I leave it in the white calibrate mode? I can't figure this part out. Thanks.
 

·
Registered
Joined
·
9,736 Posts
I like this discussion and have a question. How do you use the white calibration mode with color grab. I cannot quite understand it. I have a 6500K lamp and a calibration white card. I put the app in the white calibrate mode and point it at the card. And it seems to self adjust to that. But now what do I do?
do I switch back to normal and take grayscale readings, or do I leave it in the white calibrate mode? I can't figure this part out. Thanks.
Hi, that application is totally useless for any kind of display calibration.

If you decide to get your own meter and start the journey, the ideal meter to get is the i1Display PRO (colorimeter) and if you want to improve it more, you can add a spectrophotometer (like i1PRO2, as future step of color accurancy upgrade) to use it for creating a unique meter correction table for each of your displays, to improve your colorimeter color accurancy. To see why you need both or a lot of other details generally about these 2 meters see there.

About calibration software there free solutions, you can download:

1) HCFR from here with support forum topic: HCFR - Open source projector and display calibration software

2) The Free DPS version of LightSpace CMS can be used also with an i1Display PRO meter, there available to read various guides on the Light Illusion website.

The specific guide for use with LightSpace DPS is here.

But there is a lot of potentially useful/interesting info in the various guides on the website also.

Support forum topic: Free LightSpace DPS - Manual Display Calibration

There is a HCFR tutorial from a forum member here: The certainly not complete user guide to get to know and calibrate your TV

After selecting your calibration software, you have to find a calibration disk which had been created specifically for each software because there differences between calibration disk that can affect the final result when you will use not proper patterns for each measurement run.

You will playback the calibration disk from the source you use to playback your movies, to include to the adjustments you will make any player internal processing/colorspace conversions inaccuracies, to have your full video chain calibrated.

For improve your calibration knowledge, here are some useful links generally for calibration:

http://www.tlvexp.ca/

Video Calibration From The Inside - Volume I - 2nd Edition-1

http://chromapure.com/demos.asp

http://chromapure.com/ChromaPureManual.pdf

http://www.spectracal.com/downloads/...n%20How-To.pdf

http://calman.spectracal.com/user-guides.html

http://calman.spectracal.com/webinars.html

https://www.youtube.com/user/SpectraCal

http://lightillusion.com/why_calibrate.html

http://lightillusion.com/delta-e.html

http://lightillusion.com/manual_cali...ots_guide.html
 

·
Registered
Joined
·
19 Posts
I can tell you without a shadow of a doubt that putting my Vizio on Normal color Temperature which is essentially Warm and putting up a 100% white flat pattern I'm able to get closer to D65 than what is default. It's not hard to tell that Normal is very Red and after lining up RGB with app it's a MUCH closer reference white. Undeniable
 
21 - 33 of 33 Posts
Top