Dragonophile

I submit pictures to a website that limits pictures to 12 mb size or less. The files I get are often 14-18mb in size so I need to reduce them. Since all my pictures are jpeg, I usually reduce them by setting my jpeg compression to 97 or 96 in my editing software. There is also a resize option where I choose pixel size reduction. I don't know if these two options work similarly or differently. What would be the best method to reduce pictures size from 14-18 mb to under 12 mb? [I use an old version of a semi-obscure editing program called Zoner Photo Studio but this question would apply to Adobe Elements too, I think.]

Are there any programs that allow you to save by file size, so I could just pick 11mb or 10 mb for example? When I save by my current method of changing jpeg compression, I really don't know the resultiing file size until after I do the save. If I am just missing something obvious, please gently let me know.

Orphoto Loc: Oregon

Along with most, im not familiar with Zoner. But, you are on the right track. Gentle increases in compression followed by actual size reductions are the order of the day. Keep in mind the website's intended actual use. If this is just for public viewing any worrying is academic; it wont matter anyway.

R.G. Loc: Scotland

I believe the optimum method is to leave quality at 100% and reduce the resolution (number of pixels). That of course depends on whether the loss of resolution is acceptable (in most cases it will be). You should be able to specify the number of pixels along the long edge. Getting the file size right will involve some trial and error.

If it's not too critical and you have the option to do so, just specify the maximum file size (many PP editors have that option). Most uncondensed jpegs have quite a lot of wiggle room so the loss of quality will in most cases be negligible.

Typically resolution matters only for prints. Any on-screen viewing typically requires far less resolution than the original file had.

Dragonophile

The website is mostly for screen viewing, but some people do download pictures from the website for personal use. Yes, I do keep all the files in original size in case someone asks for a larger file than the website allows.

Can you specify file size in Elements? I have access to it.

ELNikkor

I've always used Office Picture Manager. Edit, Resize, Choose your percentage.

Architect1776 Loc: In my mind

PSE lets you very easily downsize.
Just go to save as and choose from 0 to 12
0 is smallest and 12 no reduction.
I do 2-3 for most websites.
Real easy no calculations or other such nonsense.

JW from PA

Try this site, I use it when needed:
http://www.shrinkpictures.com/

Joe W.

Longshadow Loc: Audubon, PA, United States

Probably, but I just use the Windows Image Resizer power toy.
Does what I need VERY quickly and without the need for an editor.

coolhanduke Loc: Redondo Beach, CA

If you have P.S., you can batch downsize files to the size you need and save them in a separate folder.

CHG_CANON Loc: the Windy City

Adjust the pixel resolution first, then the JPEG quality. All the reasons, and some screen captures of popular software, are provided in this link:

Recommended resizing parameters for digital images

bikinkawboy Loc: north central Missouri

The free Nikon View software can. Click on an image, then on “convert “, the current file dimensions are displayed and you then type in the dimension size you want.

DirtFarmer Loc: Escaped from the NYC area, back to MA

Windows users can use IrfanView. When saving an image, the savings dialog allows you to specify a particular file size OR a quality setting (controls the degree of jpg compression).

A setting of 96 or 97 is probably much more quality than is absolutely necessary, but will work to decrease the file size slightly. Decreasing pixel count (image dimensions) is recommended by some people but not by me. Fewer pixels WILL result in a smaller file size but the decrease in image quality is probably greater when decreasing pixel count than it would be by increasing jpg compression (my opinion here -- have not studied this [yet]). It really depends on the end use of the image. If it's just going on the web, use Paul's recommendation since most monitors are limited in pixel count. If the image is going to be used in an application where resolution is important, the full size image will be better.

A couple years ago I studied the degradation of jpg images with multiple re-compressions, and in the process measured the RMS change in an image from an original tif to a jpg as a function of quality setting. The abstract is at https://www.uglyhedgehog.com/user-page?upnum=3000 and that page contains a link to the full study (14 pages). I did not see any noticeable degradation of images with quality settings of 70 or more. Of course, some people are more picky than I, and some images will probably have larger changes than others, so this is a subjective determination.

All the programs I used to write jpgs had a quality setting range of 1-100 except Photoshop, which has a quality range of 0-12. It appears to me that the comparison between Photoshop and the other programs is not linear, but I have not tried to measure it. My estimate is that the Photoshop quality setting of 0 appears to be equivalent to something in the 30-50 range of the other programs.

bsprague Loc: Lacey, WA, USA

"....limits pictures to 12 mb size or less."

In Lightroom Classic, the Export routine has a simple file size limiter. It wants the number in kilobytes so for a 12MB limit the number would be 12000.

DirtFarmer Loc: Escaped from the NYC area, back to MA

You're right. I haven't really looked at the export dialog in LrC recently. I just always export things at the quality setting I used for the last 15 years.

I wouldn't be surprised if many other editing programs had the same capability. The OP didn't specify what program was being used.

PS: don't expect the output to be that number exactly. It's an upper limit, and there will be conditions that limit the lower value available so it could be higher than specified (although that will only happen if you give it a really low value).

imagemeister Loc: mid east Florida

I use Elements and image resize. I reduce overall pixel dims by 50% at a time by reducing the linear dimension on the long side using "bicubic sharper" until I get close to the desired size and then fine tune. Bicubic sharper is best for reductions. I really like to keep JPEG compression to "10-12"