Is there a way using Lightroom, to take a thumbnail for a photo gallery (e.g. jpeg, png) and reduce the filesize from like 2MB down to 150KB but not degrade the photo quality?
Thanks.
Thanks.
Anything that reduces file size is going to reduce quality. You can use the Export function to specifiy a specific px size and kb size.
Yes but they are all reducing pixel dimensions. Once you discard those pixels and down sample the information is gone. Quality is therefore reduced.
I think the save functions between the two programs are largely similar.
I'd recommend you export a JPG from photoshop at 200x200, highest quality. That'd tell you a ball-park file size, if you find that to be useful info.
If a particular site is picky on file size, I adjust until I get to the required size. Most people don't go as far as creating their own thumbnails though as most hosting sites handle that for you already. You'd just upload your image of some spec, like 1600px width or some such, and the hosting service (like smugmug) just bangs out any thumbnails needed.
I exported one of my images at 200x200, looks to be 56k or so in size, but that's still dependent on a variety of things. And while photoshop or any exporting application will try and optimize for quality, like @mollyc says, throwing away pixels is throwing away pixels. Going from an image that's say 10320px x7752px out of a camera to 200/200 is going to be of extremely low quality regardless of optimizations. Obviously, you can't reverse the process very well either.
Good point, but I haven't used Photoshop since like 2000 and it has a steep learning curve - plus it costs lots of money - so I was trying to avoid that for "Phase 1".
My question pertains to a photo gallery website that I build from scratch. (I actually know how to resize images n PHP, but that is way too much work for my needs.)
True, but I was under the impression that maybe Photoshop's optimazation algorthim was superior to others.
You make it sounds like not really.
Sure. Pixels are pixels. When people upload full sized images to prodibi or scaled images to Flickr or SmugMug (or Facebook, Instagram or...), the websites store the uploaded image and generate a thumbnail. When you click on the thumbnail they display the stored full image. The thumbnail itself doesn’t get scaled back to a full sized image (But maybe I don’t understand your question fully).
I was just saying that I am not using some service like Flickr - that my website is hand-coded.
And that while I do know how to code in PHP a function that takes a full-sized image and shrinks it, that for this basic site I'm not doing that.
Thus, I was asking for the best way to shrink an image of say 3000px by 3000px down to 180pxby 180px and make that thumbnail look the best but with the smallest filesize.
Is your goal to have thumbnails created before they get to your site or after? And is the end result to only display 180px by 180px thumbnails?
Ps does have an option that will create a more compact JPEG or PNG than its normal "Save as..." option. It is currently found hidden in the File>Export submenu and its name has varied a bit through the various versions of PS generally being "Save for Web", "Save for Web & Devices", or similar....
True, but I was under the impression that maybe Photoshop's optimazation algorthim was superior to others.
You make it sounds like not really.
20 years later though, most image processing tools provide similar optimizations for JPG output. Same quality too. Just pointing out that it doesn’t have to be Photoshop.