Dallas Posted May 19, 2014 Share Posted May 19, 2014 I am wondering if it is necessary to upsize images so they are 300 dots per square inch. When I process raw files in Photoshop Elements then open the image in the main window, the image size indicates 240 dpi. I've been upsizing to 300 dpi for Alamy, and this makes for large files. There has recently been discussion on the size of files to send, with people recommending large files be downsized to 24mb. Mine are already over that size it 240dpi. It seems daft to upsize to 300 dpi then downsize the file. Can I just leave it at 240dpi? Link to comment Share on other sites More sharing options...
Bryan Posted May 19, 2014 Share Posted May 19, 2014 Yes. I don't do any upsizing these days, and only consider downsizing if I am dealing with a stitched panorama. Just check to ensure that your files are over the minimum size limit, pixel dimensions 24MB, from memory. Use Image filesize in Photoshop. Don't know if you have that in Elements. Link to comment Share on other sites More sharing options...
Guest Posted May 19, 2014 Share Posted May 19, 2014 I am wondering if it is necessary to upsize images so they are 300 dots per square inch. When I process raw files in Photoshop Elements then open the image in the main window, the image size indicates 240 dpi. I've been upsizing to 300 dpi for Alamy, and this makes for large files. There has recently been discussion on the size of files to send, with people recommending large files be downsized to 24mb. Mine are already over that size it 240dpi. It seems daft to upsize to 300 dpi then downsize the file. Can I just leave it at 240dpi? You can change the dpi without changing the size of the file, simply uncheck resample in the image size dialog box for older PS versions or now in CC, it's fit to original size. Whilst 300 dpi is industry standard, if you can't export from RAW in Elements at a set dpi (as in Photoshop), then simply leave as is. Link to comment Share on other sites More sharing options...
Martin P Wilson Posted May 19, 2014 Share Posted May 19, 2014 Just a small point it is dots per linear inch which equates to 90,000 per square inch. 300 per sq inch would be less than 18dpi! Link to comment Share on other sites More sharing options...
SFL Posted May 20, 2014 Share Posted May 20, 2014 Changing dpi doesn't change file size, just the dimension at a given dpi setting. I don't know anything about Elements, but (with Photoshop) you can change the workflow option (in ACR, Adobe Camera Raw) so when you bring images to Photoshop, they are open at 300dpi (default is 240 dpi). I am sure you can do the same with Elements. Sung Link to comment Share on other sites More sharing options...
Guest Posted May 20, 2014 Share Posted May 20, 2014 Changing dpi doesn't change file size, just the dimension at a given dpi setting. I don't know anything about Elements, but (with Photoshop) you can change the workflow option (in ACR, Adobe Camera Raw) so when you bring images to Photoshop, they are open at 300dpi (default is 240 dpi). I am sure you can do the same with Elements. Sung AFAIK, you can't change dpi in Elements other than via image size. It's not the same as exporting to Photoshop. Link to comment Share on other sites More sharing options...
SFL Posted May 20, 2014 Share Posted May 20, 2014 AFAIK, you can't change dpi in Elements other than via image size. It's not the same as exporting to Photoshop. As I said, I have no experience with Elements. I mentioned the above just in case. Link to comment Share on other sites More sharing options...
Robert M Estall Posted May 21, 2014 Share Posted May 21, 2014 My Pentax K-5 usually shoots at 300 dpi (set to RAW only) but loses the plot once in awhile and slips to 240. Of course I can switch to 300 without resampling but it's a pain to add "check size" to my workflow. The handbook says nothing on the subject. Link to comment Share on other sites More sharing options...
Russell Watkins Posted May 21, 2014 Share Posted May 21, 2014 The only reason for specifying "300dpi" in file metadata is so that clients who don't understand file sizes are satisfied that they're getting a "high resolution" file. Specifying "1 dpi" in the box would give you a file exactly the same size as one with "20 gazillion dpi" in the box. DPI is only important when it comes to printed output. Technically, you should vary the dpi depending on print size and viewing distance and you should do this at the time of printing (so once again, what's in the box is academic because you may well be changing it at print time). And reducing the dpi at the printing stage is why you can get large prints with more than acceptable quality from 6MP images Link to comment Share on other sites More sharing options...
dustydingo Posted May 21, 2014 Share Posted May 21, 2014 The only reason for specifying "300dpi" in file metadata is so that clients who don't understand file sizes are satisfied that they're getting a "high resolution" file. Specifying "1 dpi" in the box would give you a file exactly the same size as one with "20 gazillion dpi" in the box. DPI is only important when it comes to printed output. Technically, you should vary the dpi depending on print size and viewing distance and you should do this at the time of printing (so once again, what's in the box is academic because you may well be changing it at print time). And reducing the dpi at the printing stage is why you can get large prints with more than acceptable quality from 6MP images Purzakly Russell !! As you say, you can have two indentical cameras, set up so one gives you images at 10 gazzillion dpi (I think 20 gazillion is overkill), the other set to give you images of exactly the same pixel size but only 2 dpi (again, imo it's overkill at just 1). The resolution of the images (remember, they have exactly the same pixel dimensions) is identical. They will appear on your screen as identical. When I open images in CS6, it shows 240 dpi. In NX2 it shows 300. I could change either of them to any number I want, but as long as the pixel dimensions remain unchanged, it's simply a waste of effort. So the answer for the OP is, dpi can be whatever you want it to be, just make sure you uncheck "resample" (as Geoff said above, and if you have that choice) if for some (unnecessary) reason you are going to change the dpi . . . that way the pixel dimesions will not change, and you will not make the file bigger or larger as you indicate you have been doing. Apropos of the above, I'm still amazed on a regular basis by printers who still think dpi = resolution :-) dd Link to comment Share on other sites More sharing options...
Peter Noyce Posted May 21, 2014 Share Posted May 21, 2014 Just to be picky quoting dpi is only relevant in an offset printing environment. For digital images it's ppi (pixels per inch) and that's what the Raw processor is quoting. The trouble is designers are so used to working for print and having trans scanned to size for repro, dpi and ppi are assumed to be the same thing. Some elements of the industry in their ignorance are fixated on '300dpi' so I give them that as it keeps them happy. It helps to call it ppi as it helps to remind people that it's size of the digital file you're talking about not the size it's going to be reproduced. As others have said you may want to work on 300ppi for a quality magazine but for a poster you may only work on a quarter of that or even much less. Unless you are supplying sized and prepped for a specific use it's not your decision as to ppi just as it's not your decision on sharpening. Link to comment Share on other sites More sharing options...
Dallas Posted May 29, 2014 Author Share Posted May 29, 2014 Thanks for all the advice. Sorry I haven't replied sooner. Link to comment Share on other sites More sharing options...
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