Question: what size is optimal for posting own images here / size limits?

sorry, probably I am blind. Searching for but cannot find max. size / limitations of (own) images if I want to post them in forum - Image and Video Galleries Section.

Is there a max. resolution (pixel x pixel) or max. file size or other? And could you please advise, what size best to use, also to avoid images being re-compressed or "optimized" after upload. Thanks!
 
There used to be a guide many years ago - but I last time I looked I also could not find it - so either you're not blind, or I am too!

For what it's worth, I seem to recall some guidance about trying to restrain the longest side of your shot to 2000 pixels. I tend to resize to that, and then save as a jpeg at a size that reduces my file down to around 1MB. Others may have some better ideas.

Last shot I dd this for can be found here https://www.canonrumors.com/forum/index.php?threads/waterfalls.36959/post-827377 and for me, while not quite like the raw image on my system in the office, it is nonetheless a fair enough representation (to my eyes at least).

I can't answer to whether this then leads to the shot being re-compressed or optimised after upload - don't know if anyone else knows this?
 
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Zenforo (the forum software) handles attachments by resizing them to the limits set in the software. This is a 16.7 MP file with 4995 X 3353 96 ppi dimensions. It is obviously resized to a smaller size.

Here is a explanation I found in the Zenforo forum.

However, uploaded files are first resized based on the maximum physical dimensions (pixels) set in the ACP -> Options -> Attachments: Maximum Attachment Image Dimensions. If the resized image is below the maximum file size (KB) limit, then it will be allowed.

4995 x 3353 image (1 of 1).jpg
 
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So, I'm seeing about 1024 width, probably the same height. However, when clicking the image, it opens to a larger size, so it is resizing the image to one size and displaying it at a max 1024 size? I'm not sure if a different monitor ppi affects the size we see or how that figures in.

I'm going to keep on uploading 2048 X 2048 240 ppi because thats one of my memorized lightroom settings.
 
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Zenforo (the forum software) handles attachments by resizing them to the limits set in the software. This is a 16.7 MP file with 4995 X 3353 96 ppi dimensions. It is obviously resized to a smaller size.

Here is a explanation I found in the Zenforo forum.

However, uploaded files are first resized based on the maximum physical dimensions (pixels) set in the ACP -> Options -> Attachments: Maximum Attachment Image Dimensions. If the resized image is below the maximum file size (KB) limit, then it will be allowed.
I take this to mean that our uploaded images are first resized, and at that point, virtually all of them meet the maximum file size limits.
 
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ok, thanks all for the information so far.

Interesting that there is no easy to find, clear guideline. I'd ike to export from Lightroom in the "right size", avoiding resizeing as well as any issues with forum software etc. Was thinking of 1600 pixel on the long side, which is what I do on other forums usually.
That should work. Since the larger photos get resized as they are uploaded, they all end up working well in the forum. I have not had one rejected for being too large, but it is possible if you have a very large image and file size such that reducing it to 2048 X 2048 results in a file larger than about 5 MP.

I tried making a photo very large by saving it as 9096 X 9096 and came out with a 55 mp image that would not upload. I could probably experiment to find out the limits. I believe that it is not a simple computation. The server itself has file size limits, then the forum software, the ppi, size, and file size all play into the limit.

Then, there are style sheets that control what is displayed and how. I don't expect that many people understand how it all works together, the site coding was probably contracted out.

This may become a issue with high MP camera bodies that have very high density photosites like 100 mp, but as long as the file size is within the limits after the image is resized, it should work. If it becomes a issue, Craig will see if it can be fixed.
 
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