Weird problem

[Colin]

Ok, why did this happen:

- Business card designed in CorelDraw X5. Exported as EPS for printer.

- Background is CMYK 80% black (filled rectangle).

- Simple logo on top of that, but after "filling" logo with a brushed metal fill, the file was huge, so I used the "Convert to Bitmap" command, and it made it smaller. Great.

- Received cards back from printer, and the background area of the logo was no longer clear, but a darker grey than the b/g. All must be re-done.

- When I look at the file in Corel, the background of the logo is clear. It is also clear when I import the same EPS file back into Corel. But when the EPS file is opened in Illustrator, the darker background tightly surrounding the logo shows.

What is going on here?

 

[signage]

Colin try export to PDF and see what it looks like.

 

[GAC05]

Did you convert the entire file to a bitmap or just the logo on top of the black background?
Can you post up pic of the file?
Most likely Draws transparency in the eps file is not translating correctly into AI or the printer's software.

wayne k
guam usa

 

[Colin]

Did you convert the entire file to a bitmap or just the logo on top of the black background?

Just the logo (a very simple vector thing) on the 80% black b/g.

The darker grey background (69 63 61 58) of the logo that showed up in Illy was bound tight to the outer perimeter of the logo.


I did figure out a fix for it; I tried not converting the filled logo to a Bitmap, and that worked, but I'd really like to know what the heck happened to cause this. Not converting it to a Bitmap results in a 57 MB file. I really don't get that either, given that it's just a 2" x 3.5" business card. The fill was not a big file, just a 966 x 431 px, 105 KB JPG.

From now on I'll be checking every file in Illy CS5.

 

[Colin]

Here's a 25% portion of the card, one as it should be (Card 2), and one with the dark b/g (Card 1).

(On the correct one, it is supposed to have that slight drop shadow).

 

[GAC05]

http://www.oberonplace.com/draw/tricks/halo.htm

 

[bob]

Long ago I gave up sending printers EPS, Ai, or PDF files. What they get from me is a 300ppi jpg with no compression and no smoothing.

At first, all of the printers complained. I told them that's what they were going to get and that's what it damn well better look like or I take my business down the road. I told them to not mess with the image but to let their RIP sort it out. Now I get back exactly what I send them.

Most recently I ordered a large curved trade show background/wall/whatever from a vender who ought to know with it's about. I sent them a jpg file, they sent me back a proof that instantly invoked a gag reflex.

I called them and talked to some twit who knew little and understood nothing. I asked to talk to whomever was actually doing the pre-press and printing. I told the guy to just run the jpg exactly as I sent it to them with the rendering intent for bitmaps set to 'Perceptual' and every other rendering intent set to 'No Color Correction'. Since it was a bitmap the other rendering intents really didn't matter.

He hemmed and hawed and finally said that they'd do it but I had to accept whatever the result was. I told them nonsense, it was their job to hit the image I sent them and I'd just told them how to do it. They did it exactly as I directed and the results were perfect. The guy called me back and said that they'd never considered doing anything like that, they'd always figured that they had to convert everything to CMYK before sending it off to print. He was astounded at the quality of the print and he was enlightened somewhat.

 

[oldgoatroper]

Long ago I gave up sending printers EPS, Ai, or PDF files. What they get from me is a 300ppi jpg with no compression and no smoothing.

Bob, you may be getting great results with your method, but what you've described above simply does not exist -- a JPG file that is not compressed.

A JPG file, by definition, is compressed and JPG compression is, by definition, lossy compression.

If you want to send your files uncompressed, use TIF format with no compression, or if you want, use TIF format with LZW compression which is non-lossy compression. Both yield the same uncompressed image data when loaded into a image editing program or RIP. Some RIPs, however, require uncompressed TIFs -- but it's easy for a service provider to open a compressed TIF and save it as uncompressed before RIPing...

 

[Rodi]

Bob,
how would your scenario handle a 5th color? Also text? I tend to agree with you about no color management (no one really understands color management), but you can send them as .pdf, .eps, or even documents, just run the numbers I have (highlight 5c2m2y0k/shadows 80C70M70Y70K)

 

[Colin]

I did figure out a fix for it; I tried not converting the filled logo to a Bitmap, and that worked, but I'd really like to know what the heck happened to cause this. Not converting it to a Bitmap results in a 57 MB file. I really don't get that either, given that it's just a 2" x 3.5" business card. The fill was not a big file, just a 966 x 431 px, 105 KB JPG.

Any insight on this point?

 

[oldgoatroper]

Not really, Colin... but I can tell you how I would have approached it.

I would have brought my brushed metal bitmap into corel simply as a bitmap then power-clipped it into the vector object. Negates the need for converting the vector object into a bitmap.

You do know about Power-clipping, right?

 

[Colin]

You do know about Power-clipping, right?

Yes, and I'll try that tomorrow and see what the file size results are. Thx.

 

[bob]

...

A JPG file, by definition, is compressed and JPG compression is, by definition, lossy compression....

True, sort of. While there will be some physical loss, it isn't statistically significant and certainly not visually detectable.

If you keep a jpg with no accessory compression or smoothing it takes a whole bunch of un-packing and re-packing before it even starts to deteriorate in any detectable manner. As long as you always keep it in RGB and never CMYK. If you don't then the color will see all manner of violence every trip in and out of an application, The jpgs I'm sending get packed once, when they are prepared to be sent off for printing.

While the purists may well recoil in horror at using jpgs, I wouldn't have a memory gobbling tif up my butt if there was room for a freight train. But what do I know, I've only been doing this since before the most of you, and your parents as well, were born.

 

[Rodi]

Bob, I would not be so sure about the RGB at certain RIPs. When I worked on Rampage, RGB would process pretty well, but the Agfa Apogee RIP, it was lousy no K, but CMY all heavy, and it did not matter .jpg, .eps, pdf or native.

 

[Colin]

To me, (with my limited knowledge on this), it seems that printing a vector rather than a bitmap (jaggies) always results in a superior, sharper print.


shrug

 

[bob]

To me, (with my limited knowledge on this), it seems that printing a vector rather than a bitmap (jaggies) always results in a superior, sharper print.


shrug

Depends on the resolution of the bitmap. Converting vector objects into a 300ppi bitmap yields an image visually indistinguishable from the vector original. The human eye has a hard time distinguishing one part in 100 with one part in 130 generally considered the upper limit, mutants excepted. For practical purposes, a print of a 150ppi bitmap is pretty much visually identical to a print of vector objects. You might be able to discern which is which using a loupe, but not with the naked eye.

That being the case, if your ship your stuff out at 300ppi, it's pretty hard for someone to screw it up. Mke sure that everything is RGB and then the printer is responsible for any color shifts, not you.

 

[Jackpine]

I agree with Bob's method. The results are always good. I use it all the time.