Problem with pic losing greys

[ABickersteth]

Hi All

I am using PSP X4. I have been drawing a very large picture (3840x2160) at 8 bits / channel. The picture is of a very large building, in great detail, therefore it needs to be very large! Part of the pic is a wall of huge masonry blocks each of which is a different grey. However, I am finding that over the course of time as the picture is saved and reloaded my blocks are disappearing due to the colours used not being correctly saved, i.e. PSP gradually saves individual blocks as the same colour when they were not the same to begin with!

I tried cutting the pic into 2 smaller ones to reduce the dimensions in case that was the problem. The pic is now 1493x1623 at 8 bits/channel but I am having the same problem. I have tried using only non compressed, non lossy file formats. However the problem still occurs when the pic is saved as a png file and as a pspimage file. When saving as a pspimage file I only select the uncompressed option from the range of those available.

Please help!

Aidan

[Jean-Luc]

Could you show a before/after picture (or part of picture) ?
Difficult to advise without an image.

[hartpaul]

If you are saving as a jpg then you may be having problems here as continual jpgs saves change colors slightly and it is cumulative.
Instead save your unfinished file as a .pspfile. It takes more space but you don't lose quality or have color changes.

[ABickersteth]

Hi

I did a test of saving the smaller 1493x1623 part of the pic as a pspimage file over 100 times, both on my laptop and desktop. There was actually no difference I could see in the greys before and after saving when comparing with the dropper tool. The only thing I can think of is that the contrast is not as good on my laptop's screen so the different grey blocks often look the same shade even when they are actually different shades of grey.

I have noticed that PSP X4 defaults to the last save type used which can be tricky, i.e. if you load up a pspimage and go to save it, the program defaults to the last image type saved even if this is jpg, so its easy to save an image as a jpg by mistake. I looked at the program preferences and couldn't see an option that allows images to be saved to their native type as default. If so this would be a handy feature to add in the future to avoid accidentally losing detail from an image that may have received many hours of work!!

Thanks for your suggestions

Aidan

[rondo]

Save a jpeg using Save AS, then click the button that says Options on the screen. The default is a low resolution which could effect grays and colors, raising the resolution might help, and make sure the box Embed ICC Profile is checked. These settings for each image format will remain for the each image you save such as jpeg without having to set them again each session.