Enlarging jpegs

paudie

Hey guys, normally I submit Raws, but someone is asking for a 12Mb jpeg, just wondering how to get this from a 7Mb raw image, is it possible?

5uspect

paudie wrote: »

Hey guys, normally I submit Raws, but someone is asking for a 12Mb jpeg, just wondering how to get this from a 7Mb raw image, is it possible?

Thats a bit daft of the person to ask that. Easiest way is up interpolate them up so that the filesize is increased. Maybe up the resolution 300% and then compress to the desired 12MB. Upscaling may make the image softer so you may have to sharpen.

Alternatively tell that person to get a grasp on reality...

Placebo

He should be asking for an X by Y resolution and the dpi for printing purposes, if anything. Silly asking for file size. Very LOL

mervifwdc

Then lets go have a laugh at a lot of the stock sites! They expect he the photog to create the large files for them.

I think it's crazy too, but it's not unusual. X pixels by Y would make more sense, DPI does not matter then as you can set it for your purposes afterwards PROVIDED you got the correct number (enough) of pixels in the first place.

Merv.

paudie

So do you think I should just do a normal conversion without interpolating it up?
It just goes to 2-3 Mb then.
He's the manager of a grpahic design company and says that's the size they normally deal with.

paudie

Strangely enough I just figured out I can save the image as 25Mpixel file when converting, didn't know I could do that :P

So how do I do this interpolation thingy then?

Thanks for the help by the way.

melekalikimaka

http://www.ononesoftware.com/detail.php?prodLine_id=2

i use that

Valentia

http://www.prophotomagazine.com/article/HowTo/46/

melekalikimaka

Valentia wrote: »

http://www.prophotomagazine.com/article/HowTo/46/

Stair Interpolation
Some people have discovered that you can get better results when upsampling by increasing the image size in several small increments rather than one extreme step. This technique is referred to as stair interpolation. One advantage to using stair interpolation is that it will work on 16-bit mode images and it requires no additional software other than a standard photo editor, such as Photoshop. The concept of stair interpolation is simple: rather than using the image size command to go directly from 100% to 400%, you would use the image size command and only increase, say, 110%. Then you would repeat the command as many times as it takes to get to the size you need. Obviously, this can be tedious if your software does not have some automation capability.

think thats the best free option

paudie

Cheers everyone, I just went from 6144x4096 (4Mb) up to 6500x4333(11Mb)

And I can see absolutely no difference between the two. Ah well, suppose I'll do as I'm told, I am the newbie after all.

Thanks again for all the help.

Roen

I've seen a few places specify 40-50Mb jpegs as the minimum that they will accept.

nilhg

Would a 3-4 MP compressed jpeg not be close to 12 MP uncompressed in PS, might not that be what Paudies contact was looking for.

If he's the manager of a graphic design company, I would have thought he wold know his way around PS well enough to interpolate it up himself.:rolleyes:

Valentia

I'd imagine Nilhig is right and it is the decompressed size they are talking about. Compressed would make no sense and, depending on how they are compressed, they could end up any size when decompressed.

I also agree that the star interpolation works well. I have done it a few times.

paudie

So how do I find the decompressed size?
Jeez I used to think I knew my way around post processing :P

DotOrg

fact is: the owner is talking nonsense, he doesn't understand what he's talking about.

back in the day when you scanned slides, you asked for a files size in MB. even a pro dSLR doesn't give jpgs of taht size and they can easily be printed double page spread in magazines at 300dpi with no loss of quality

you could try explaning that to him but he'd probably get defensive as he thinks he knows what he's talking about

number of pixels is ALL that matters, nothing else

Valentia

paudie wrote: »

So how do I find the decompressed size?
Jeez I used to think I knew my way around post processing :P

Bottom left of image in PS: Select "Document Sizes" on the pointer at right.

paudie

Does that mean your one above is 72 MB?
Thanks again guys.

Valentia

paudie wrote: »

Does that mean your one above is 72 MB?
Thanks again guys.

Yes. It's at 240 dpi though, which is the dpi that Lightroom exports at as default. The dpi has a big effect on the file size. Remember to change the dpi in PS from menu: "Image/image size" with resample image turned off. The bit depth (8 or 16 bit also effects the file size significantly) Lightroom exports to PS at 16 bit.While the comments about the person that wants them not having a clue are correct I'm just pointing out a few things. Tho' I'm no expert TBH.