RBG Values changes after manual input

[mc21389022]

I am at a loss here.  I have this issue where Photoshop Replace color won't change the color to a specific RGB value but when I use my paintbrush or paint bucket it will use the correct value that I set it to manually.  I've never had this issue before and it's a move I've done numerous times without issue.  Example of what I am doing.  Use Replace color to make the background 255. Then use replace color again to change 255,255,255 to 237,237,237 once I apply that move it and confirm the color in the info pallet the numbers are 238,238,238. Open up the color picker and the numbers match the info pallet of 238,238,238.  If I used the paintbrush and set it to 237,237,237 and paint it works.

The color profile is sRGB 8-bit, and the color picker is set to point sample. I've used HEX codes, I've reset preferenced, I've updated to the later version of PS, and nothing... 

As a side note, I have also had this happen in the image resize where for example you set a dimension to say 5 inches save, close, open, and check size, it says 4.9999in.  Not that it makes a difference but the point is Photoshop changes values whenever it feels like it...

[davescm · Accepted solution]

Hi

On the first issue if you use replace colour to darken a selection from 255 to another value, when using the Lightness slider then you have limited granularity. So Lightness -7 will result in 238   whilst the next value  - 8 will give you 235.

If instead you selected the area and use a curve adjustment, you can achieve the exact value of 237 that you require.

On the second issue - Photoshop does not work in inches or cm it works in pixels. If you type in a value in inches, it will be changed to the nearest value that can be set in whole pixels. That will depend on the image resolution setting in px/cm or px/inch.

Dave

[mc21389022]

Oh my.  I just realized what I have been doing wrong. You're right!  I usually use a different method and not replace color for the 327 value... Wow