Poor Quality Thumbnails

[CPla]

Hi,

Thumbnails in my gallery http://chefpla.com/gallery/index.php seem to display at rather poor quality.

I have checked the forum, so to save time -

* Config is set at GD2, server supports GD2.1.9
* Quality in config set at 80 originally, I changed it to 90 and rebuilt all the thumbnails in admin. I then confirmed that they were actually rebuilt, by using FTP.
* The thumbnail seems to be OK when I download with FTP and open with Windows viewer, so I am wondering what the issue is.

For comparison, please view the top thumbnail on http://www.chefpla.com/recipes.php?o=1&page=3&usequery=1 and compare with Szechuan Style Chicken Stew in the Gallery.

Also, I am attaching the thumbnail I downloaded from the gallery folder using FTP.

Obliged if someone could help me out.

[Nibbler]

Looks fine to me. Post a screenshot of how it looks to you.

[McKenzie]

I have  the same problem with that theme in blue: The reason is an optical effect (I think), but I don't know why .

[CPla]

Hi,

As requested. I cropped it a bit to reduce file size, saved as jpg in PS quality 12.

I know its tough judging quality from thumbnails, but I did open 3 windows (recipe page, gallery, windows viewer), put the thumbs side by side and judge that in natural light. Also, my screen is calibrated, so no issues there.

As for an optical effect, that is of course entirely possible.

[McKenzie]

http://www.icmesa.com/thumbnails-2182.html  Look at my gallery, I think that the theme background color makes an "greasy" effect. It think that is a problem of light blue- light yellow, light green etc. colors.

[McKenzie]

Copy one picture out of your gallery and it will look better on white or black background.

[CPla]

I tried copying a thumbnail onto 2 different backgrounds in PS, #FAEFDE which is the current Gallery background for the thumbnails, and #FFFFFF or pure white. That did not make any difference to the perceived photo quality.

I also changed the background in the gallery itself to #FFFFFF, and switched back and forth about 3 times, and I'm afraid it made no difference.

I have however increased thumbnail size to 110px from 100px in the hope that a larger size may improve perception, and may go up further when I have the time to tweak this.

Meantime, I have to say that there really does appear to be a quality issue with the thumbnails.

Can anyone suggest a solution?

[Nibbler]

You could try switching to imagemagick or building your own thumbnails manually.

[McKenzie]

Is it really better. Please tell me your opinion.

[CPla]

For me no difference in the photos you posted, but its night here and I'm looking at it under yellow light so I'd really need to take another look in the morning. For now I can say there is no difference in basic clarity at the detail level.

[Joachim Müller]

@McKenzie: you need to make up for the additional jpeg compression and use a losless format like png when trying to show such granular differences (that is: the screenshots need to saved as PNGs).

[CPla]

Re: building thumbnails manually, I have tried this in PS but the file size for 100px is 20-25Kb even at quality setting 5 or 6. Lower than that and photos are awful.

Is there a workaround or an alternative method to build manually?

[Joachim Müller]

Try PNG.

[McKenzie]

I found the error  .

Look at these grapics (German) into the line "148px × 81px (skaliert auf 150px × 82px)" I will start a new topic for that problem.

[McKenzie]

Its the problem of the theme "Rainy day", its    scale the thumbnails to 147*xx or 148*xxx or 149*xxx so they look like smeary pictures, we must fix our theme 

Yeah, try the theme 2bornnot2b and you will see that your thumbnails looks like gold.

[McKenzie]

The new topic is here: http://forum.coppermine-gallery.net/index.php/topic,55066.0.html

On http://chefpla.com/gallery/index.php is nearly every thumbnail scaled so his thumbnail looks not so good.

[CPla]

Problem appears to be solved.

Thanks to McKenzie for identifying what it was and Nibbler for the fix in the other thread McKenzie started.

And PNG is indeed giving smaller file sizes for the thumbs.