Can anybody point me to "official" guidance on image resolution/size for Arfcom's server? I know I've seen a post with this answer, but I can't seem to find it now. I have most definitely found threads where others are complaining about the same symptom that prompted me to find the answer to this question (very noticeable loss of detail in uploaded images), but I've not found "official" guidance on resolution. I thought I saw that images should be 1200 pixels on the long side - but that does not appear to be accurate. It appears that images uploaded to the Arfcom media server are sized to 900 pixels on the vertical side.

Observe the following images (all exported directly from Lightroom at the same settings except the "long" side value). Note that the two canyon shots are the same height of 900px despite having uploaded one at 1200px. For those using real computers and monitors (rather than mobile devices with screens barely larger than a camera's), note the difference in sharpness in the two images of the waterfall. The "soft" rendition of the Arfcom version of the 1200px image is not the same as the local copy used to upload to Arfcom. Placing the two copies side by side on my end shows the Arfcom version is softer in a manner similar to that shown here.

This behavior is not seen when linking to external hosts like my SmugMug or Flickr accounts.

Thanks.

           

Uploaded @ 1200px long side	Uploaded @ 900px long side
Attached File	Attached File
Attached File	Attached File

ARFCOM has a limit of 3MB for file size for pictures. I know high resolution doesn't work well with that limited size. Thus I usually crop my pics I upload to fit that 3MB size.

Like this one. Original size is 5MB and edited out a lot of the stuff to get to just below 3MB. By cropping out parts I didn't want and some I wanted left there. Thus 3MB is not much where 5 to 10 MB would be better yet I know that they do not have that much space on the servers thus why it is set to 3MB

Attached File

Thanks. When exporting from Lightroom for Arfcom, I keep the file size below 3Mb. My frustration is that the quality of the file I send to Arfcom is sharper and sometimes of a different size than the same image presented back to me by Arfcom.

That's part of the problem. My primary system for surfing Arfcom is a full PC on a 4k monitor - and my view is similar to the one you posted. Now try saving the images directly from your browser (not "save target as...") to your local system and let me know whether the sizes are different. If I save the canyon images above directly from the browser, they both are saved at 900px high. If I choose the "save target as..." option, then I get the version at 1200px on the long edge.

Try saving a portrait orientation at those dimensions and let me know the results. Both of my canyon pics above save as 900px on the long edge despite one of them being uploaded at 1200.

By the way, if I save your photos locally, they all show as 1200px on the long edge. If you uploaded them as 1600px, then they're getting re-sized somewhere along the way (either at the time you upload them, or at the time Arfcom serves them up). I noticed that behavior after the major site update late 2017 and that's why I have been exporting at 1200px on the long edge with file size restricted to <3Mb. Local image file looks great. Upload to Arfcom and the quality on my 4k monitor is...fuzzy. (I'll be polite.)  If I pull up my local copy that was the source of the upload and move that window side-by-side with the image showed by Arfcom, the difference can be rather distinct.

My goal is to upload an image that Arfcom will show faithfully. To do that, I just need to know the rules by which Arfcom handles images, so I was hoping there exists a page or post that spells out those rules.

As another test, here is a 1200x1200 image that shows as 1.1Mb in size as saved out of Lightroom. Let's see how it compares when served up by Arfcom and then by SmugMug.

Arfcom:
Attached File


SmugMug:

The arfcom image is displayed at 900x900 on my monitor (1650x1440); if I do "save target", it's still just a 900x900 image.

The Smugmug image displays as 1200x1200 on my monitor.

Yeah, I've had the same problems with the arfcom media server with my own files.  Most of my files are 1024 x whatever, and are displayed at something like 1000 x whatever.  Even if I upload a 1000 x whatever file, with the intent of preserving resolution, the image on the Arf server has a lower file size, beyond what would be attributed to stripping the Exif.  It's annoying.  It's definitely a deal breaker for maintaining my membership at this level.