Mac Files Won't Open on PC on at Photo Lab!

[jet travis]

My wife, whose English isn't the greatest, asked me to post this. She is the

digital darkroom expert in the family, so please bear with me as I try to explain

the situation.

 

Her software is Photoshop CS. The OS is Mac OSX.

Everything works fine until we save a disc and try to open it on a PC or at a

photo lab. At that time, we get a message which says something like "Cannot

open because it is the wrong kind of file."

 

Any idea what's up with this and how to fix it. Thanks so much.

[btmuir]

What application do you use to burn the disc?

[sandy_labana]

What kind of disk are you saving on? When I save photos (JPEG format) on

CD, the software that burns CD asks me if I want to save for both PC and

Mac. I don't know if PC will read CD if I selected option for Mac only.

[bob_rushing]

I do this all the time.

 

First I make all my adjustments to colors, contrast etc. You should really capture images in a loss-less format such as camera raw, convert them into PS and then save them. The camera raw is your 'digital negative'. Do not edit jpeg and re-save if you are concerned about image quality. Use a loss-less file format directly from the camera raw for image editing. jpg is ok for final output to a commercial lab. If your camera only offers jpg, then save the origingal image as your digital negative and edit a copy. What I have found is that each time you open, edit and save a jpg you recompress the data and loose image quality. I've done this.

 

Then, if it isn't, I convert the image to 8 bit Image>Mode>8 Bit;

 

Next I save a copy of the original as jpg or jpeg (what ever you want to call it) in the hightst quality;

 

Last, I burn the images to CD in ISO9660 format.

 

What I have noticed is that when I use a lab, they can't open files in PS format. They also have problems with large files such as TIFF. But generally, images that I reproduce as fine art, I do on the Mac. I have a Windows box that I use for other things that don't require accurate colors but I can open the same files on both machines all the time.

[awindsor]

The byte order for TIFFs is different on Macs and PCs. The Mac will read both so I save TIFFs in PC byte order by default. That is the only file gotcha that I know. If the CD is mounting then it is unlikely to be a burn problem. Pure Mac disks just don't mount.

[jeffcallen]

This could be as simple as filename extensions.

 

First, try to make sure the filenames have no spaces in them, and end in .jp if they are jpegs and .tif if they are tiffs.

 

If that desn't work, try 8 character filenames with .JPG extensions. Also make sure the images are not in folders with spaces in the folder names and that the folder names are 8 characters or less.

 

If you're saving Tiffs in Photoshop, make sure you check the box "windows byte order" not "macintosh byte order" when you save the file.

[jeffcallen]

I forgot one detail: Resource forks.

 

On the mac, files have 2 parts, the Resource fork and the data fork. The data fork is "the file itself" and the resource fork is a bit of "info about the file."

 

If you're transferring files from a mac to a windows machine, sometimes when you open the file browser on windows, you see 2 almost identically named files for each "file" created on the Mac. Try opening both of them on the PC, often the first one in the list is the "resource fork" and it is much smaller, and windows doesn't know what to do with this file, thus generating your error.

 

Opening the larger file should work, provided you have the correct filename extension, as windows figures out what kind of data is in a file based on the filename extension. If you arbitrarily change the filename extension, say from ".jpg" to ".tif" or even ".doc" then you may have a totally unopenable file on windows.

[patricklavoie]

Did the CD as been burn in Mac/PC? Did you have all the ,JPG or .TIF after the name of the

file...

[Uhooru]

What format were the files. I doubt if it has anything to do with the burning software or

burner. PSD files should x-platform no problem. Same with jpgs. If you are using Tiff's you

have to make sure that in the mac, you save the bit order for PC. Mac reads both mac bit

order and pc, but pc only reads pc. I used a flash stick and or burned cd's to take stuff back

and forth between the macs at school and my home pc. Never a problem. Now I use mac at

home.

[eric_gundersen]

If I might add my two cents here..

 

I don't know what kind of equipment they use at the photo lab you are using, but I used to work in a photo lab with a Fuji Frontier, and we used to run into this all the time with Mac files.

 

Generally the problem was with people writing the discs in Mac format, which PCs cannot read (without special software, but most labs will not have this). I don't know if things are different now (this was a few years ago when I worked there) but also we could not read multisession discs, and could not read discs with sessions that were left open, and as Jeff has mentioned, with TIFFs being saved with Mac byte order instead of PC byte order.

 

The Frontiers run on Windows (ours ran on Windows NT), as do most all photo kiosks. Be sure you save everything with that in mind if you are going to be printing those files anywhere but your own computer and printer.. If you save everything to be compatible with Windows it should work.

[eric_gundersen]

Oh, almost forgot... we also could not read PSD files. IIRC, we could only read TIFF, JPEG and GIF.

 

We had quite a few people complain about the fact that we could not read PSD files, but the software the Frontier used did not have that capability.

 

Perhaps they didn't want to pay Adobe royalties? who knows..