LR Resolution

Hi Guys,

Just a very quick question? when Exporting your or my photo's it give you a chance to change the resolution . my it set at 240 is this right or too low

Output size and resolution depend on what you intend to use the photo for. Are you exporting photos for print or web display, etc.?

Resolution is irrelevant. I never use it. When exporting, I select the pixel dimensions, and the max file size, only. No matter what resolution you pick it only matters when printing. If you pick 240 and the printer can do 600, you are wasting print quality. If you pick 600 and the printer can only do 300, the print driver will interpolate it for you. Don't bother with resolution.

a Small Dance Studio has ask me to the end of year Concert and so they can give the photos to the parents along the vid, so my guess that some of the parents may want to print their photos
off

so its best to leave it at 240 then

matt84au wrote in post #18189149
a Small Dance Studio has ask me to the end of year Concert and so they can give the photos to the parents along the vid, so my guess that some of the parents may want to print their photos
off

Resolution in LR export makes no difference at all to the photo if exporting for screen. Resolutions of 1 and 1000 give identical images. Give it a try and see.

If exporting for print, it is a little different. It appears to affect the sharpening done by LR to the photo. Therefore to do this properly, you would have to know the print size ahead of time so you can specify the right resolution. If you don't know how the file will be used, then it's anybody's guess. It doesn't make much difference anyway. Try it and scrutinize the files to see for yourself.

Other than LR sharpening, I don't think there are any other consequences for normal applications.

So actually, "Resolution" in LR is a misleading parameter.

Cheers Guys for all your help

If you look at the Export options, note that you choose size options along with resolution/PPI options. If you want to use the photo to "share" via the Web or, say email for viewing with a device, the ppi "tag" doesn't matter as long as your height/width is rendered in pixels (not inches or cm or such). That way, the image is displayed in pixels on the device, which has a resolution in pixels per inch -- the image can be displayed "as is" or the software may resize it to "match" the desired display.

Printing can bring up different issues. If you export using inches and ppi, then the image will be rendered accordingly. So, if you set dimensions in inches and leave your ppi to 240, the software will resize the image accordingly. It can be smaller than the original or it can be larger if you un-check the "Don't Enlarge" option. the point is, when preparing for print, you will pay attention to both the dimensions and the ppi. For a small print, such as a 4x6 or an 8x10 (cropped properly) you can typically just leave the default ppi at 240, or maybe increase it to a "standard" 300 ppi. The image will typically be "shrunk" but your print quality will be good. For larger prints, you may need to consider enlarging the image in pixel per inch resolution (to meet a print quality "standard"). This would be to work with some print providers that want a particular resolution at the given size (in inches, cm, etc.). These providers sometimes will request a "standard" of, say, 300 ppi. Whether that matters to you will depend on your viewing of the printed image.

For Web use (such as posting here or on Facebook or wherever) we don't bother setting dimensions in inches, but we do need to pay attention to dimensions in pixels. Here, the maximum width/height dimensions are 1280 pixels, so if you set those dimensions in your Export dialog, the image will "fit" here (without needing to be resized), although you might also want to consider the resolution of your viewing device. But the ppi "tag" won't matter -- you can set it to 1 ppi and the image will still show using the pixel dimensions.

Bassat wrote in post #18189147
Resolution is irrelevant. I never use it. When exporting, I select the pixel dimensions, and the max file size, only. No matter what resolution you pick it only matters when printing. If you pick 240 and the printer can do 600, you are wasting print quality. If you pick 600 and the printer can only do 300, the print driver will interpolate it for you. Don't bother with resolution.

As Archibald states above there is a difference. If you are exporting by specifying a pixel dimensions then yes, resolution is irrelevant. If you are exporting to a certain dimension like 4x6 Lightroom calculates the output size in pixels and it does use the resolution setting. 4 x 6 x 240 = 960x1440. 4 x 6 x 300 = 1200x1800. The resolution setting isn't there for no reason. It works differently depending on how it is configured.

nqjudo wrote in post #18189186
As Archibald states above there is a difference. If you are exporting by specifying a pixel dimensions then yes, resolution is irrelevant. If you are exporting to a certain dimension like 4x6 Lightroom calculates the output size in pixels and it does use the resolution setting. 4 x 6 x 240 = 960x1440. 4 x 6 x 300 = 1200x1800. The resolution setting isn't there for no reason. It works differently depending on how it is configured.

The flaw in your logic is that there is no point in exporting dimensions. I can export a full-resolution 6D raw photo and still print it at any dimension I want. That file is 5742x3648 PIXELS. I can print it 4"x6"; the printer cannot handle that kind of resolution, so the driver automatically downsizes it for print. I can print that same photo 19"x12", and it will look just fine because the printer can natively do 300 DPI (resolution). If I output that same photo again, this time at 76"x48", it will look like crap because that is only 75 pixels per inch.

LR resolution is irrelevant. Which is exactly what Archibald states above.

Bassat wrote in post #18189303
The flaw in your logic is that there is no point in exporting dimensions. I can export a full-resolution 6D raw photo and still print it at any dimension I want. That file is 5742x3648 PIXELS. I can print it 4"x6"; the printer cannot handle that kind of resolution, so the driver automatically downsizes it for print. I can print that same photo 19"x12", and it will look just fine because the printer can natively do 300 DPI (resolution). If I output that same photo again, this time at 76"x48", it will look like crap because that is only 75 pixels per inch.

LR resolution is irrelevant. Which is exactly what Archibald states above.

Plenty of reasons use dimensions. There are web-based print services that don't accept uploads as big as your 6D full size file (let alone a giant file that was modified for a different purpose prior) so they have to be exported at smaller, controlled dimensions. You also state a good case for exporting to a specific dimension in that not everyone wants their files resized by the downstream service or printer driver. Lightroom does a much better job at resizing for print than most print services and printer drivers. Something is not irrelevant to the absolute because it is beyond the scope of your personal use. Exporting the biggest file possible might be a good catchall for you but that doesn't make it the best - or even workable- practice for everyone.

nqjudo wrote in post #18189315
Plenty of reasons use dimensions. There are web-based print services that don't accept uploads as big as your 6D full size file (let alone a giant file that was modified for a different purpose prior) so they have to be exported at smaller, controlled dimensions. You also state a good case for exporting to a specific dimension in that not everyone wants their files resized by the downstream service or printer driver. Lightroom does a much better job at resizing for print than most print services and printer drivers. Something is not irrelevant to the absolute because it is beyond the scope of your personal use. Exporting the biggest file possible might be a good catchall for you but that doesn't make it the best - or even workable- practice for everyone.

And you are correct, sir, on several counts. Lots of web-based print services do not accept full size files. Using the full-size file my export from above, if I want to upload it to an entity that requires smaller file size and/or pixel dimensions, LR allows me to pick any PIXEL dimension and/or FILE SIZE I want. POTN upload are 1024 long edge/250k. The RESOLUTION box serves no purpose.

I understand your point about not wanting others to do your 'adjustments'. I send full-res files to Walmart's on-line print service. I've used them for hundreds of prints. The largest being 11"x17". They do excellent work. I can't imagine Walmart is the best in the business, and they handle resizing large print just fine. A shooting buddy uses a 7D, and gets 20"x30" posters done at Walmart. They are down-sizing mine, and up-sizing his posters. Excellent results, all around. What else do you need?

I never said I use full-size exports as a 'catch-all'. I output at the proper size for the job at hand. E-mail get 800 pixel long edge and 150k. Web (POTN) gets 1024 pixels and 250k. Prints are always full size. I also never suggested that anyone/everyone export full-res JPG files. All I said is that there is no good reason to use the RESOLUTION box in LR. I stand by that statement.

I don't think anyone minds if you (or anyone else) uses the RESOLUTION box. My point is that it has no bearing on the output, which is what the OP was asking.

Sure. I get what you're saying and I'm sure we both agree that there is more than one way to get the job done. I'm not arguing with your method if it works for you. The only problem I see in telling someone that setting X, Y or Z is irrelevant or not is that we have absolutely no insight into the rest of the equation. What were his settings, goals, limitations and exactly how were the other options configured besides the resolution setting? Depending on what was already configured the resolution setting could have had an impact that was very relevant to the results. You know what works for you and I know what works for me but honestly neither one of us had enough information to offer a response as to what was appropriate. I would have liked more info and that's why I asked for it. Anyway... goodnight!

Generally, all that is said above is true - the ppi tag on an image displayed on electronic (screen) media is irrelevant. The image is displayed at the screen's ppi no matter what the tag says. However, there is there is a small exception to that general rule when exporting from LR and using (as you should) Output Sharpening, if it is set for Screen. The sharpening tool reads the number in the PPI box and slightly changes itself if the number is 150 or less (to do sharpening appropriate for normal low res screens which are around 100 ppi) or greater than 150 (to do sharpening for Retina, 4K, 5K, etc. screens). So it is not a matter of the real resolution changing, but rather the LR sharpening.

tzalman wrote in post #18189460
Generally, all that is said above is true - the ppi tag on an image displayed on electronic (screen) media is irrelevant. The image is displayed at the screen's ppi no matter what the tag says. However, there is there is a small exception to that general rule when exporting from LR and using (as you should) Output Sharpening, if it is set for Screen. The sharpening tool reads the number in the PPI box and slightly changes itself if the number is 150 or less (to do sharpening appropriate for normal low res screens which are around 100 ppi) or greater than 150 (to do sharpening for Retina, 4K, 5K, etc. screens). So it is not a matter of the real resolution changing, but rather the LR sharpening.

I thought you were going to say "if it is set for Print". I have output the same pic for screen at both 1 ppi and 1000 ppi and the JPGs have identical sizes and differ in only a few dozen bytes, perhaps bytes having to do with housekeeping like creation time. But when output for print, the sizes differ and there are many differences in the data.