HiResCovers.net

voetzoeker wrote:

QUOTE (voetzoeker @ Mar 19 2013, 10:57 AM) <{POST_SNAPBACK}>

The only way when printing on high end printers to get better quality in letters and logo's,
is to save your cover as PDF format that includes the vector info of the logo's and fonts used

Agreed. However, I doubt this applies to many folks in the cover community. A hi-res JPEG with no visible compression errors is more than sufficient for our hobby.

Shwaffle wrote:

QUOTE (Shwaffle @ Mar 19 2013, 08:40 AM) <{POST_SNAPBACK}>

Well, honestly 1GB is nothing nowadays to be honest. If you're worried about space, I'd download a drive mapping utility and see where you should be trimming the fat. (Treesize for Windows is nice). You could also look into cloud storage to hold your covers if need be.

It's more to do to do with transferring them, as I back up quite frequently. I'd rather have 500mb in 200 files than 1gb, as the transfer takes an age on my machine. Of course, this includes all my other files too, but if I can halve my image file sizes at the click of a button with no loss in quality, I may as well do so.

Kernie also raises a very good point related to storage. Most cover sites, this one included, have tens of thousands of uploads in their galleries. If we say 5mb is your average cover, we're talking many terabytes of data.

Quick scan on this site tells me there are roughly 30,000 images. That's 150Tb, which could be cut down to 75Tb with little to no loss in quality. And quite honestly, they look exactly the same when printed. I would even say saving them as a 10 in quality is unnecessary. 9, or even 8, works just as well.

Think also about time spent uploading and downloading.

Unless we're talking about printing something billboard sized, I don't think knocking the 'quality' down a few notches makes any difference to printed quality.

jwshaw89 wrote:

QUOTE (jwshaw89 @ Mar 19 2013, 11:55 AM) <{POST_SNAPBACK}>

Unless we're talking about printing something billboard sized, I don't think knocking the 'quality' down a few notches makes any difference to printed quality.

Agreed.

And, technically, something "billboard sized" could withstand even greater drops in quality, possibly even some significant pixellation. Since the intended viewing distance from a billboard is (at minimum) a dozen meters away, the viewer will never get close enough to notice such quality errors. Something that will be seen at close distance, like a blu-ray cover or a magazine spread, should probably maintain a higher level of quality than a billboard.

kernie82 wrote:

QUOTE (kernie82 @ Mar 19 2013, 06:31 PM) <{POST_SNAPBACK}>

Agreed.

And, technically, something "billboard sized" could withstand even greater drops in quality, possibly even some significant pixellation. Since the intended viewing distance from a billboard is (at minimum) a dozen meters away, the viewer will never get close enough to notice such quality errors. Something that will be seen at close distance, like a blu-ray cover or a magazine spread, should probably maintain a higher level of quality than a billboard.

Indeed, but I meant in terms of dimensions rather than purpose. Like if you were to print a dvd cover at billboard size and scrutinize it as you normally would.

I'm not sure what Photoshop's definition of a 'large file' (which it recommends saving at 12) is, but it certainly isn't a dvd cover.

I simply don't understand where the extra 3mb comes from when saving at 12 as opposed to 9 or 10. If the resolution, dimensions, and indeed quality remain exactly the same (to the naked eye), how can the file be 100% larger? Must be like dead data or something. If that even exists.

I really thought I'd overlooked something because of such a huge discrepancy.

jwshaw89 wrote:

QUOTE (jwshaw89 @ Mar 18 2013, 10:27 PM) <{POST_SNAPBACK}>

However, I notice that changing the setting to '10 maximum' (changing it to 9 results in 'high' rather than 'maximum' quality) reduces the size of the cover to around 2-3mb

I can usually see a slight difference between 10 and 11 but have to agree that the difference between 11 and 12 is very hard to spot at 100% zoom.

It also depends on your image. Grain sharpness, bright colors, and especially the color red are areas where the setting matters. If your image has a lot of pale blues, you won't notice as much loss. For instance, my Psycho custom's photos look pretty much the same, but check out the title:

6 vs. 12

[attachment=25115:6.jpg][attachment=25118:12.jpg]

[attachment=25119:Compare.gif]

I think the maximum settings are there for instances in which size is not a necessary factor. Even at maximum, JPEG compression is still being applied to the image, and if the image is saved and re-saved with JPEG compression (even at maximum applied) several dozen times, there will begin to be a decline in image quality. Kind of like the old days of VHS and the generation loss that occurs when copies of copies are made. In all my years of experience, however, I have yet to see a decline in quality occur to a JPEG that has been re-compressed countless times, but I'm sure it could occur.

That being said, since we are dealing with a situation in which our covers need to be uploaded to a server and then downloaded by others, file size should be a consideration. Leaving a JPEG at maximum quality for our purposes is unnecessary, as we have said in previous posts.

Bunny Dojo wrote:

QUOTE (Bunny Dojo @ Mar 19 2013, 06:54 PM) <{POST_SNAPBACK}>

I can usually see a slight difference between 10 and 11 but have to agree that the difference between 11 and 12 is very hard to spot at 100% zoom.

It also depends on your image. Grain sharpness, bright colors, and especially the color red are areas where the setting matters. If your image has a lot of pale blues, you won't notice as much loss.

Yeah, I noticed that sharper colours and tones are affected the more you slide down the quality.

Of course I would never save as low as 6. I think 9 is really the threshold, but even only taking it down to 11 reduces the size by over a megabyte.

Many of my own designs have a little grain added to them, which probably allows for more reduction.

jwshaw89 wrote:

QUOTE (jwshaw89 @ Mar 19 2013, 01:59 PM) <{POST_SNAPBACK}>

Of course I would never save as low as 6.

I just went down to 6 because 8 or 10 were still too good-looking to work as examples.

As Kernie mentioned, 12 makes sense when you hope to have something maintained exactly. There are, of course, better alternatives for that kind of thing these days.

But, for one more example, here's a zoomed-in piece of a red canvas saved as a JPEG at quality 9, then opened, re-saved at 9, etc. after 4 generations.

Instead of being a flat (255, 0, 0), it's now (253, 3, 2) and starting to distort at the edges.

Also, fascinatingly, each time I go to save the file, all of the new information added by the distortion makes the file size larger than if I had saved at quality 12 from the start. So the distortion you're using to decrease file size will actually increase the file size if you should try to re-save the design later. (We're all working from original .psds and such, so this doesn't matter, but it's still kind of interesting. )

[attachment=25121:test.jpg]

Bunny Dojo wrote:

QUOTE (Bunny Dojo @ Mar 19 2013, 07:31 PM) <{POST_SNAPBACK}>

Also, fascinatingly, each time I go to save the file, all of the new information added by the distortion makes the file size larger than if I had saved at quality 12 from the start. So the distortion you're using to decrease file size will actually increase the file size if you should try to re-save the design later. (We're all working from original .psds and such, so this doesn't matter, but it's still kind of interesting. )

[attachment=25121:test.jpg]

That's interesting. I suppose it makes sense insofar as you're inadvertently producing more colour tones (even if only minor variations) each time you save it. A gradient obviously holds more data than a single shade.

Likewise with the repeat saving gradually reducing the quality. If you're only reducing the quality by, for example, 2% each save, then that accumulates over a number of saves until it becomes clearly noticeable from the original.

But as you say, if we're only saving as a .jpg the one time straight from a .psd file, as is almost always the case, then this is of little concern.

Another odd thing is that you can open the image saved at quality 10, do nothing to it, then re-save it at quality 12 and the file size shoots back up to 5mb or so. Surely the absolute best quality you can get is merely a perfect copy of the image you opened? Therefore you'd think the maximum file size should be whatever it was when you opened it. As you're saving at the maximum setting, there should be no colour distortion creating more data. At least not enough to warrant a sudden 2mb increase in size.

It's a bit of a mind bender.

so as a novice hobbiest I should upload or save at what 10 or 12, what I'm getting here is if a lot of reds are used 11 or 12, but if more blues or darkness lower to 10? What's the bottom line, in the past it was always save at 11 or 12 was best. Size of file really means nothing to me as I have over 900 gb empty, hehe