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Faith_J
Sketcher Extraordinaire


Reged: 11/17/04
Posts: 5830
Loc: South coast of England
Photoshop problem
      #3339443 - 09/17/09 01:12 PM

I have a bit of a problem with processing sketches in Photoshop in that what I post on the net bears no resemblance to the picture I processed in PS!
For example, I scan a sketch in, process it in PS and it looks fine. However, on upload to the net it looks dreadful in the browser - e.g. light areas which are not apparent in PS or on the hard drive! Why the radical difference in appearance in PS vs IE8 and Firefox?

Any help would be appreciated.
Many thanks

--------------------
Visual deep sky

18" f4.3 dob
7.9" f/4 Celestron Newtonian
8x42 binos
100% visual observing...


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jayscheuerle
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Reged: 01/16/06
Posts: 4675
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Re: Photoshop problem new [Re: Faith_J]
      #3339465 - 09/17/09 01:18 PM

Under "View", set your "Proof Setup" to "Monitor RGB" and then select "Proof Colors".

This is assuming that under Color Settings, sRGB is chosen for your RGB workspace. - j

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Fight indignorance!

120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.

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Jeremy Perez
Carpal Tunnel


Reged: 08/12/04
Posts: 2125
Loc: Flagstaff, Arizona, USA
Re: Photoshop problem new [Re: jayscheuerle]
      #3339538 - 09/17/09 01:52 PM

Hi Faith, that's great advice from Jay.

Regarding the sRGB color space he mentioned, this is usually the best color model to assume other viewers will be using. If your Photoshop color settings are set up for a different color space, the image can be interpreted in unfortunate ways on other computers. Go to Edit > Color Settings and see what it says in the 'Working Spaces' section next to the 'RGB' label. If it doesn't say 'sRGB...', you'll probably want to switch to that for typical web work. (If you're a color-space Jedi or using Photoshop to prepare images for Hi-Res Epson printing/etc., then you'll probably have other color spaces you like to use.)

Let us know if any of that helps.

--------------------

Orion SVP 6LT (6" f/8 Newt) || Orion XT8 (8" f/5.9 Dob) || 15x70 Oberwerk Binoculars || Coronado PST
The Belt Of Venus || Sketch Gallery || Sketching Resources || Drawn to the Universe Column


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Faith_J
Sketcher Extraordinaire


Reged: 11/17/04
Posts: 5830
Loc: South coast of England
Re: Photoshop problem new [Re: Jeremy Perez]
      #3339552 - 09/17/09 01:55 PM

Thanks Jeremy and Jay. I will give it a go and see what happens.

Cheers
Faith

--------------------
Visual deep sky

18" f4.3 dob
7.9" f/4 Celestron Newtonian
8x42 binos
100% visual observing...


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Jeff Young
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Reged: 08/04/05
Posts: 4491
Loc: Ireland
Re: Photoshop problem new [Re: Faith_J]
      #3339736 - 09/17/09 03:33 PM

Faith --

I've had some issues with JPG that I've never been able to track down. (I keep all my sketches in monochrome, so I'm pretty sure it's not color management.)

Anyway, for about 2% of my sketches I end up having to save them in GIF because the JPG versions appear to have too few steps in the dark-gray to black range.

Cheers,
-- Jeff.

--------------------
Nikon 18x70s / UA Millennium                                       Colorado:
Solarscope SF70 / TV Pronto / AP400QMD                       Coronado SolarMax40 DS / Bogen 055+3130
APM MC1610 / Tak FC-125 / AP1200GTO                        Tak Mewlon 250 / AP600EGTO


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Faith_J
Sketcher Extraordinaire


Reged: 11/17/04
Posts: 5830
Loc: South coast of England
Re: Photoshop problem new [Re: Jeff Young]
      #3339836 - 09/17/09 04:16 PM

Thanks for the input Jeff. That could be the problem.

Also, I forgot to mention in the original post that the sketches are scanned in grayscale - could that be part of the problem?

--------------------
Visual deep sky

18" f4.3 dob
7.9" f/4 Celestron Newtonian
8x42 binos
100% visual observing...


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Jeremy Perez
Carpal Tunnel


Reged: 08/12/04
Posts: 2125
Loc: Flagstaff, Arizona, USA
Re: Photoshop problem new [Re: Faith_J]
      #3339930 - 09/17/09 04:55 PM

Faith, I just visited your latest blog entry. You made a comment about wanting to apply color to the NGC 7662 sketch in Photoshop, but couldn't because the image was scanned as grayscale. If you open the sketch back up in Photoshop, go to Image>Mode>RGB. That will convert it to an RGB image that you can then colorize as you see fit. (apologies if that's not the problem you were facing)

I also had a close look at your Stephan's Quintet sketch. You mentioned that there was an inadvertent smudge that you hadn't noticed in Photoshop. When I look at the image in my browser, that smudge is not at all noticeable. I had to open the image in Photoshop and really crank up the contrast to see it.

Have you looked at your images on other people's browsers/monitors? I wonder if your computer has an abnormally high Gamma setting that's making your browser images look bad (although perhaps they look ok in Photoshop because it's overriding that Gamma setting & making them appear as they should).

Great sketches, by the way!

--------------------

Orion SVP 6LT (6" f/8 Newt) || Orion XT8 (8" f/5.9 Dob) || 15x70 Oberwerk Binoculars || Coronado PST
The Belt Of Venus || Sketch Gallery || Sketching Resources || Drawn to the Universe Column


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Jeff Young
Post Laureate


Reged: 08/04/05
Posts: 4491
Loc: Ireland
Re: Photoshop problem new [Re: Jeremy Perez]
      #3340841 - 09/18/09 05:02 AM

Faith --

I always scan in grayscale too; as long as there's no color data on your sketch it keeps the number of things that can go wrong smaller.

If you do want to add colour later, you can follow Jeremy's instructions for converting to a different image mode.

One of the things I do when checking to see if there are "hidden" artifacts left on my sketch is to use the Image > Adjustments > Brightness/Contrast dialog, click the "Use Legacy" checkbox, and then drag the Contrast slider all the way to the right. You'll want to Cancel the dialog after doing this (or use Undo if you forget), but it will show you all the areas of your image which are a slightly different shade.

When you're all done in Photoshop, do you save your image using "Save As" or "Save for Web and Devices"? "Save for Web and Devices" gives you considerably more control over the result.

Cheers,
-- Jeff.

--------------------
Nikon 18x70s / UA Millennium                                       Colorado:
Solarscope SF70 / TV Pronto / AP400QMD                       Coronado SolarMax40 DS / Bogen 055+3130
APM MC1610 / Tak FC-125 / AP1200GTO                        Tak Mewlon 250 / AP600EGTO


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Faith_J
Sketcher Extraordinaire


Reged: 11/17/04
Posts: 5830
Loc: South coast of England
Re: Photoshop problem new [Re: Jeff Young]
      #3341008 - 09/18/09 09:09 AM

Quote:

Have you looked at your images on other people's browsers/monitors? I wonder if your computer has an abnormally high Gamma setting that's making your browser images look bad (although perhaps they look ok in Photoshop because it's overriding that Gamma setting & making them appear as they should).




I haven't tried that, Jeremy, I'll give it a go. I'll look on my aunt's computer later and see what it looks like there. I did reset my monitor (I am using a laptop, not that that should make a difference I wouldn't have thought) gamma settings a while back to get the thing accurate for photo processing (it shows all the shades on those black-grey-white bars you see on deep sky websites).

Quote:

One of the things I do when checking to see if there are "hidden" artifacts left on my sketch is to use the Image > Adjustments > Brightness/Contrast dialog, click the "Use Legacy" checkbox, and then drag the Contrast slider all the way to the right. You'll want to Cancel the dialog after doing this (or use Undo if you forget), but it will show you all the areas of your image which are a slightly different shade.

When you're all done in Photoshop, do you save your image using "Save As" or "Save for Web and Devices"? "Save for Web and Devices" gives you considerably more control over the result.




Hi Jeff, I must admit I am a useless Photoshop user, so I hadn't considered what you suggest. I'll have a go and see what happens. I do use the 'Save for web' option because I find that I can see exactly how large, or not, the file is.

Thanks for the input, guys, I'll let you know how I get on.

--------------------
Visual deep sky

18" f4.3 dob
7.9" f/4 Celestron Newtonian
8x42 binos
100% visual observing...


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