Photoshop resizing and printing

[kkraczek]

I have a photo that I have cropped and sharpened to my liking in PS. It was taken at the largest (best) setting with my Digital Rebel, but when I check the image size, it falls at about 9x13 after cropping. Is there a way to enlarge (maybe even double?) the photo in PS without sacrificing image quality? I'd like to have it printed for framing at the local camera shop. Thanks!

[gmen]

Try this product... I use it when I need to make poster size prints from digital files... it does a mighty fine job:

http://www.trulyphotomagic.com/short...uct_serie_info

[Sebastian]

I have a photo that I have cropped and sharpened to my liking in PS. It was taken at the largest (best) setting with my Digital Rebel, but when I check the image size, it falls at about 9x13 after cropping. Is there a way to enlarge (maybe even double?) the photo in PS without sacrificing image quality? I'd like to have it printed for framing at the local camera shop. Thanks!

Go to image->image size and type in what size you want, and at what DPI. Make sure bicubic interpolation is selected.

[gmen]

There's a lot to be said about different methods of interpolation. Have a look here: http://www.sportsshooter.com/message....html?tid=3512

Also, here: http://www.interpolatethis.com/

[Sebastian]

There's a lot to be said about different methods of interpolation. Have a look here: http://www.sportsshooter.com/message....html?tid=3512

Also, here: http://www.interpolatethis.com/

Gmen,

How much of a difference do you actually see, in say a 13x19 print? I have tried most of the available trails out there, and anything smaller than wall size seems to be irrelevant what interpolation you use. I use Qimage with vector interpolation and in 8x10s or smaller it makes no difference whatsoever. It fdoes start to shine when I take a really tight crop and blow it up though.

IMO those tools have their place in a highly technical pro toolbox for enlarging to absurd sizes, but for most amateurs and hobbyists they are pretty much just a waste of money. If you have extensive experience with the tools, where do you think my views fall? Am I close, or way off the mark?

Also, what sort of files are you interpolating? I can see it being much more useful to someone who enlarges D1H files for posters, whereas a D100/10D user may not need as sophisticated interpolation methods. And 1DII/1Ds users needing even less.

Would love to know what you think, you seem to have much more real-world experience than I when it comes to this stuff.

[gmen]

Hi Seb... Some of the football clubs I shoot for have requested prints in the region of 20" x 16" to use in their boardrooms etc. Some of the shots I have 'expanded' to this size have been crops (around 20-40%) of the original images. The pics I refer too were shot on a 10D at the highest resolution using L series glass - although sometimes in jpg format and not always RAW.

A friend of mine is the supervisor at local digital processing lab and we have made some direct comparisons in the final quality of images printed to this size (and larger - the lab has an A0 printer) - using different interpolation techniques. The s-spline interpolation technique is significantly better at all these large sizes. The sharpness of the image is retained, edge-definition is good and there are less 'artefacts' in the finished image. All the 'customers' have commented on the final quality in a positive manner.

As you say, it is horses for courses - but surely we all want the best tools in our toolboxes. The software I think was around the £35 mark ($50 or so) so it didn't break the bank either.

And sorry Kristin, I don't mean to hijack your thread... I hope this info is still of use to you. I noted that you wanted to print twice the size of 9x13... so assuming it's inches we're talking then some of these techniques may come in handy for the best result.

[Sebastian]

Hi Seb... Some of the football clubs I shoot for have requested prints in the region of 20" x 16" to use in their boardrooms etc. Some of the shots I have 'expanded' to this size have been crops (around 20-40%) of the original images. The pics I refer too were shot on a 10D at the highest resolution using L series glass - although sometimes in jpg format and not always RAW.

A friend of mine is the supervisor at local digital processing lab and we have made some direct comparisons in the final quality of images printed to this size (and larger - the lab has an A0 printer) - using different interpolation techniques. The s-spline interpolation technique is significantly better at all these large sizes. The sharpness of the image is retained, edge-definition is good and there are less 'artefacts' in the finished image. All the 'customers' have commented on the final quality in a positive manner.

As you say, it is horses for courses - but surely we all want the best tools in our toolboxes. The software I think was around the £35 mark ($50 or so) so it didn't break the bank either.

And sorry Kristin, I don't mean to hijack your thread... I hope this info is still of use to you. I noted that you wanted to print twice the size of 9x13... so assuming it's inches we're talking then some of these techniques may come in handy for the best result.

Gmen,

Thanks for your response! If I was selling posters on a regular basis I too would most likely be using something like this, for the crops but also for just having any sort of advantage over someone who doesn't use it.

I will have to talk up my friend who does all our printing for my day job, maybe he'll be willing to "donate" his large-format inkjet for a few hours to run some tests.

Thanks again.

[gmen]

I guess as with all things photographic, there is an element of subjectivity here also! My preference for s-spline may not be shared by you - however, there are 10 algorithms included in the tool I use. There are many other 'up-samplers' to be found as PS plug-ins or stand-alone versions - a quick google whack yields a good few!

In the real world again, a good tool like this may still be able turn that very loose crop into a very nice 12" x 10" enlargement for the grandparents' mantelpiece. You can't beat using the best technique when taking the picture - but that's not always possible and if there's a tool in the box (and it doesn't cost the earth) then it WILL pay for itself (financially or otherwise).

Looking at the bigger picture (excuse the poor pun), it seems to me that it's all down to the mathematics behind the interpolation algorithm. Hmmm. I'm off to a darkened room.

[kkraczek]

Thanks guys, and don't worry about hihacking my thread. I've learned a lot! I may try PS first, since I already own it, but will definitely look into the other options as well.

I'll be using this feature quite a bit in the future as well, so it will more than likely be worth the investment. Thanks again!

[christopher_platt]

Pardon me, I'm the rookie, don't mean to be stupid, but. . .

have you tried that thing that's in Scott Kelby's "The Photoshop CS Book for Digital Photographers"? The one about changing the units in image size to percent and then entering 110% and repeating that to upsize it to the size you want? I don't usually blow stuff up larger than 11x14 or 11x17, but Mr. Kelby says it works. . .
Chip
PS Hope I didn't violate any copyrights on that one. . .