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MargaretR
9th February 2015, 10:44 AM
So I'm trying to set a custom (one touch) WB using a grey card, and the EM-10 is having none of it.

This is my newly-IR-converted EM-10, with which I'm now experimenting. Apparently for this particular IR filter, WB on a grey card is recommended, but I can't get the camera to 'take' it. All I get is the "X WB no good" message.

The card was in bright sunlight; I've tried over-exposing by 1, 2, 3, 4 and 5 stops (the maximum, it seems); I've upped the ISO; I have the aperture wide open at f2.8. Still, it doesn't want to know.

I've successfully done the WB on a white card, and on green grass, so the system does work ... just not with grey.

Any suggestions, anyone?

Or am I doomed to have to carry and include a grey card in every shot I ever take? :(

Ricoh
9th February 2015, 10:59 AM
At what wavelength range does the converted camera operate?
I suspect it's what's termed 'near IR'. IR is sensitive to temperature, isn't it?

MargaretR
9th February 2015, 11:29 AM
It's a 590nm filter. Other than obviously not being 'visible light' I have no idea how that impacts anything in terms of settings.

Graham_of_Rainham
9th February 2015, 11:47 AM
There are several Inks & Dyes that absorb near IR while appearing to produce the required colour in "daylight".

They are used a lot in ID cards where scanners can see hidden patterns using IR light.

You may have a grey card that absorbs IR making it look black to the sensor

http://www.hwsands.com/category/26.aspx

Graham_of_Rainham
9th February 2015, 11:50 AM
You could always ask about something like these as they are plastic.

http://www.7dayshop.com/products/7dayshop-pro-grey-white-black-10-x8-card-exposure-and-colour-calibration-set-ref-7dsmqdgc-b-7DSMQDG-B

MargaretR
9th February 2015, 01:49 PM
You could always ask about something like these as they are plastic.

http://www.7dayshop.com/products/7dayshop-pro-grey-white-black-10-x8-card-exposure-and-colour-calibration-set-ref-7dsmqdgc-b-7DSMQDG-B

Thanks Graham. I was looking at something similar (http://www.ebay.co.uk/itm/UK-3in1-Digital-18-Gray-White-Black-Card-Set-Photography-Exposure-Balance-Strap-/331425313550?pt=LH_DefaultDomain_3&hash=item4d2a7cf30e) on eBay ... worth a punt at 2.59 anyway. My grey card is a Jessops roughly-A4-size one, which is supposedly standard 18%, but to my eyes does look rather dark. It certainly seems too tinted for the EM-10, which does carry a health warning about things "too dark or too tinted" to be captured as WB.

Everything is a learning curve!

Graham_of_Rainham
9th February 2015, 02:10 PM
This looked "interesting" and may be of some use.

http://www.davidclapp.co.uk/blog/view/calibrating-white-balance-to-process-infrared-images-in-lightroom

stoates
9th February 2015, 04:05 PM
Hi Margaret. To set custom WB on my E-5 I have to use a white target, not a grey card. If it doesn't find white I get a fail message that may be similar to yours. I know you have tried using a white source, did you test the custom WB with your filter afterwards to see how it looked? I find that regardless of using a custom WB with my 8 stop ND I still require further manipulation in LR to correct the colour.

Invicta
9th February 2015, 05:59 PM
On my IR converted camera I use an area of green grass to set the custom white balance.

Then I use Olympus Viewer software for the initial conversion as, unlike Lightroom, Olympus Viewer can read the custom white balance setting.

MargaretR
9th February 2015, 06:57 PM
Hi Margaret. To set custom WB on my E-5 I have to use a white target, not a grey card. If it doesn't find white I get a fail message that may be similar to yours. I know you have tried using a white source, did you test the custom WB with your filter afterwards to see how it looked? I find that regardless of using a custom WB with my 8 stop ND I still require further manipulation in LR to correct the colour.

Yes, neither the white WB nor the green WB is giving me what I think it should look like, at least according to the sample images from this filter on the conversion company website. I did anticipate further work in LR, and/or even a custom DNG profile, but I do want to try and get the WB as good as possible to start from, and I just feel I'm not there yet. Further messing about to be tried yet.. :)

MargaretR
9th February 2015, 06:59 PM
On my IR converted camera I use an area of green grass to set the custom white balance.

Then I use Olympus Viewer software for the initial conversion as, unlike Lightroom, Olympus Viewer can read the custom white balance setting.

Ah, there's a thought. I have Olympus Viewer installed, but have never actually used it very much time to have another look. Thanks! *chr