Author Topic: Getting the best from a JPEG export  (Read 437 times)

Offline dhb2206

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Getting the best from a JPEG export
« on: 2019 January 26 00:52:15 »
I'm probably just doing something wrong here, but whenever I export to JPEG I lose a serious amount of detail and the image darkens substantially. I have a feeling it is a difference in colour space between monitor and JPEG that is causing the issue, but I haven't a clue how to solve it. And, yes, I know that JPEG compresses the image, but I shouldn't get better results from a simple screen grab!

Help please.... :-)

PS Export to PNG works far better.
« Last Edit: 2019 January 26 01:15:32 by dhb2206 »

Offline pfile

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Re: Getting the best from a JPEG export
« Reply #1 on: 2019 January 26 20:17:15 »
did you stretch the image with the HT process? if all you have is an STF applied to the image (green bar along the side of the window's name tab on the left) then the underlying data may just be too dark to be represented properly in jpeg.

rob

Offline dhb2206

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Re: Getting the best from a JPEG export
« Reply #2 on: 2019 January 27 05:55:38 »
Rob,

Yes, fully stretched. I find I have to somewhat overstretch for the JPEG to have a decent lightness level, unlike the png export. I reckon I'll just stick with png seeing as that works for me.

Cheers,

David

Offline John_Gill

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Re: Getting the best from a JPEG export
« Reply #3 on: 2019 January 27 09:05:40 »
Hi,

I think the .png is a 16 bit file compared to .jpg of 8 bit.

space is not black
John
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Offline Juan Conejero

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Re: Getting the best from a JPEG export
« Reply #4 on: 2019 January 27 10:32:35 »
As Rick has pointed out, this is most likely the result of having screen transfer functions (STF) active for the image in question when you saved it as a JPEG file. Bear in mind that STF does not alter image pixels, but just their screen representation.
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Offline dhb2206

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Re: Getting the best from a JPEG export
« Reply #5 on: 2019 February 04 00:25:29 »
I have a feeling this may actually be something to do with my computer's JPEG setup. I'm getting the same with good old daylight shots from Lightroom as well. Anything going to JPEG is darkened from what I'm seeing on the screen (then of course there is monitor calibration). I may be tech savvy, but maybe not savvy enough!  ;)