The HUGE amount of compression visable in the sky and on the tail is unbelieveable. Honestly now if I viewed that shot in the large version and if it wasnt my own, I'd say to myself "how did that get in ?".
The strage thing is that when I uploaded it, it had NO compression whatsoeverand looked completely different.....
Jderden777 From United States of America, joined Jan 2000, 1749 posts, RR: 31 Reply 1, posted (11 years 11 months 4 days 21 hours ago) and read 1382 times:
the shot looks absolutely fine to me....not compressed at all...it's perfect! i would definitely have added it to my database...i don't see any compression in the sky...and the tail...it looks good to me....
Mcringring From , joined Dec 1969, posts, RR: Reply 6, posted (11 years 11 months 4 days 20 hours ago) and read 1325 times:
I can see some compression by the nose, the wing and the tail, but it doesn't look like that big of a deal. Of course when you upload something and it turns out looking different it's easy to get upset. Especially since the scripts are supposed to decrease the file size without any loss in quality.
EGGD From United Kingdom, joined Feb 2001, 12443 posts, RR: 37 Reply 11, posted (11 years 11 months 4 days 19 hours ago) and read 1274 times:
I see that compression, on both shots, maybe it is you guys who should get your monitors checked out! I typed out some crap before about why you see the compression so bad on these shots, but I guess its not really that important.
TomH From United States of America, joined May 1999, 960 posts, RR: 2 Reply 19, posted (11 years 11 months 4 days 17 hours ago) and read 1225 times:
Well, you got me to open the thing up twice, so I suppose that helps the hit counter. I don't understand how you feel you can judge the amount of compression by looking at sky, rather than detail on the aircraft itself.
More importantly, what was the file size you uploaded compared to the large version on A.net? That ratio should tell you something significant about the actual amount of compression. I noticed also that your H was <1024. I thought we were trying to standardize on 1024 at Johan's suggestion about 6-8 months ago. Yes, I know, it's optional, but I'm curious to know why so many folks aren't following the recommendation.
Ckw From UK - England, joined Aug 2010, 660 posts, RR: 17 Reply 20, posted (11 years 11 months 4 days 15 hours ago) and read 1205 times:
Tom, for info, compression is more detectable in the sky (or any areas of similar tone) than the aircraft because .jpeg works by compressing areas of similarity by throwing away "unnecessary" pixels. This can become apparent as a "blocky" appearance on what should be smooth tones (because some of the transitional colours have been dumped).
In areas where there are significant contrast variations (eg. on the plane itself) the compression program assumes this means interesting detail, so throws away less.
Another thought on this - don't some dial-up "speed-up" programs apply compression on the fly? Is it possible some ISP's might do this?
Da fwog From United Kingdom, joined Aug 1999, 867 posts, RR: 9 Reply 21, posted (11 years 11 months 4 days 10 hours ago) and read 1192 times:
Colin, how would this work?!!? You have to get the data before you can compress it, by which time it's already reached your PC. You could only compress OUTGOING data! As for ISPs doing it - the processing overhead to re-compress a jpg would be prohibitive. Any idea how many there are in the average web page?
Agree with your comment about the sky though. And the reason this is more detectable if you don't have your graphics card set to enough colours is that the exact colour chosen by the compression algorithm may not be available, so your graphics card will choose the next nearest one. This just compounds the "blocky" effect of the compression and makes it look even worse!
Ckw From UK - England, joined Aug 2010, 660 posts, RR: 17 Reply 22, posted (11 years 11 months 4 days 8 hours ago) and read 1175 times:
Chris - you're right of course - it was late, I'd just spent hours fixing my PC, I was so releived just to be able to get it online again that I wrote any old rubbish - I was thinking of on-the-fly compression on the server side.
TomH From United States of America, joined May 1999, 960 posts, RR: 2 Reply 23, posted (11 years 11 months 4 days 4 hours ago) and read 1169 times:
I understand what you are saying about the sky. I think GIF files work in a similar manner, compressing more the white background of a document and less the printed area. Still, when someone says they can see it in the sky, are they looking at the image 100% or (more likely) some greater magnification? I didn't notice anything in the sky at 100%, but I haven't taken a second look.
I have heard AOL.com compresses all images unless you contact them and request they desist. I would assume this is on xmit side of their server of course.
Ckw From UK - England, joined Aug 2010, 660 posts, RR: 17 Reply 24, posted (11 years 11 months 4 days 3 hours ago) and read 1164 times:
Tom - I can't see any compression either - I think it was a case of people viewing in with a 16 bit display setting - can look similar. Gif files work slightly differently in that they use a very limited palatte for images - which is why its a poor format for photos.
Colin K. Work, Pixstel
25 Aer Lingus: Thank you all for the inputs and please please please understand that this was not any gimmic to get extra views. It was something that I felt looked
26 TomH: Martin, It was a while back that the image deminsion size of 1024 was brought up. I increased my average width to agree with what I took to be a new s
27 Da fwog: A.N. DOES compress the jpgs you upload. This is pretty sensible when you think about it. Some people optimize their jpgs before uploading (to get maxi
28 TomH: Is the compression automatic? Hard to imagine they would do it manually. They can't tell how much compression I have already applied, right? So how ar
29 Ckw: Tom - I think that's why they recommend upload with 0 compression, as the subsequent compression has a cumulative effect. Cheers, Colin
30 TomH: You are probably right on reason for the 0 compression request. To be truthful, I laughed when I first read that 0 compression advice way back. To me,