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johnnyt123
03-04-2014, 11:57 AM
Has anyone tried using their laptop screen with a white background to take flats frames??
Does it work??

John

Octane
03-04-2014, 05:53 PM
Yes. I used to do this when shooting with lenses.

It works well -- so long as the screen is evenly-illuminated.

H

popkrab
04-04-2014, 03:29 AM
I use laptop screen as well as my iPad too. It work well equally with my luminicent sheet.

johnnyt123
04-04-2014, 01:58 PM
Thanks guys...

I gave it a go...
seems to do the trick well.....

LightningNZ
04-04-2014, 04:38 PM
I'm a huge proponent of this method.

If the screen is big enough then you'll want to take many flat exposures with a range of rotational angles and side-side, up-down translations so that any blemishes will be evened out.

Cheers,
Cam

johnnyt123
04-04-2014, 04:57 PM
Don't you have To keep the optical train setup exactly as it is when you image when you take flats?
How else will the program know where the dust particles are.??

MrB
04-04-2014, 05:00 PM
I think Cam means to move the screen, not the optical train.

Octane
04-04-2014, 06:12 PM
I used to sit the camera down on the laptop (17", so it was big enough) and just move the camera left and right, then up and down.

Take between 16 and 25. Don't forget to take corresponding darks frames.

All of this should be done at the native ISO of the system (for Canon, ISO-100).

H

Screwdriverone
04-04-2014, 07:58 PM
For the blank white screen (adjustable too, in this program) use Al's Virtual light box, which is on the resources section of this website under files.

Here is the link ( I am using the iPad so I hope it works OK)
http://www.iceinspace.com.au/download.php?fb0f13a57baca875bea5be 135555aca5

Cheers

Chris

LightningNZ
06-04-2014, 07:54 PM
Sorry for not being clearer. Yes, as Simon said, just move the screen relative to your optical setup. I actually think there is good value in rotating one relative to the other as if there is any sort of grid pattern in the screen you will break this pattern up.
Cheers,
Cam