Soft images direct from a PC

[Brian Sugden]

Why are some images that I upload direct from my PC soft on this forum when the original is pin sharp? I've been advised to use a third party like flickr but don't really want to set that up just to post images on this forum. One thing I have noticed is that images taken with my 1DX appear sharper than those taken with a 1D3 or 40D.

[ST-EOS]

Re: Soft images direct from a PC

Brian you've asked a question that I had considered asking here previously, sorry I can't help you with an explanation but... I wil watch this thread with great interest as like you I don't want to set up a flickr account to overcome the issue.

[Muscat]

Re: Soft images direct from a PC

I can't answer the question fully other than to say that the algorithms used by the web hosting software when uploading them seem to soften just about all images posted and to get somthing that represents what you see on your monitor you need to add a bit more sharpening to the images before posting them, I personally export a low res jpg copy to a temporary area on my PC that I have added extra sharpening to and then upload that, i typically have to add about 15-20% more sharpening to get a good image on the web.

I have found that it is not only this site that suffers from the probem but some others as well.

[colin C]

Re: Soft images direct from a PC

i typically have to add about 15-20% more sharpening to get a good image on the web.

Me too.

[MX5]

Re: Soft images direct from a PC

I can't answer the question fully other than to say that the algorithms used by the web hosting software when uploading them seem to soften just about all images posted .

Yes, if I recall my JPEG standardisation work (from the 90's) ... this is problem with a heavy handed approach in the quantization step of the JPEG algorithm used in compressing the image. This will cause perceptible edge 'issues' which will make the image appear less sharp (i.e. soft). It could be this site applies aggressive compression to it's own images ... which is why they look soft whereas external images (say on Flickr) look sharp. Anyway just thinking aloud.

Quantization is just one trick that reduces information in the image because the eye-brain can't normally tell this has been done.