TIP: How To Super Size Your Image - by Jeff

[Chief Editor]

This month TIP is written by Jeff a.k.a. Photoshopabuser.



How To Super Size Your Image

This is a real quick way to super size one of your images with very little pixilation. This is also one of those things that seem too easy to be true.
It is very easy to downsize an photograph for a smaller print or the internet, but making an image larger can cause all kinds of problems. If you have ever tried it, you know what I mean. The following story is based on a great idea from a Photoshop wizard, Jim DiVitale. Here is the original image all cropped, color corrected, and ready to grow.



The first thing you need to do is open a duplicate copy of your image and make all the needed adjustments. I cannot stress the importance of working on a duplicate and not the original. When you are done and have a final, flattened image, open the Actions palette.



Click on the small triangle at the top right of the actions palette and this menu will drop down. Look down the menu and you will see the New Action button. Click on that one once

This tutorial sort of kills two birds with one stone. Not only will it show you how to enlarge an image, it will also show you how to create an action of your very own! When you click on the New Action selection, you will see the following box.



Type in the name of your new action and put it in the desired Action Set. You can create a new action set in the Actions Palette. A real nice shortcut when using actions is that you can assign them their very own Function Key! Pick out a key and record it somewhere so you don't forget about it. You can also pick a color for that action of yours to make it jump out a bit if you don't assign it a Function Key.

After you have named your action, you are ready to start super sizing your image!

Click on the Record button and you are ready to go. Click on Image/Image Size on the toolbar and the Image Size box will appear. Make sure that the Resample Image box is checked. You will also want to change the document size unit to Percent. In the Document Size section of the box, you will want to enter 110 for the width of the document.



This effectively increases the size of your image 10%. Click OK to resize your image. As soon as you are done with that you will want to stop recording your new action. Press the square button on the bottom left of the action palette.



For some reason, 10% works wonders but in order for you to get a poster size image you will have to do this a lot, hence the creation of an Action. Instead of going to the Image Size menu every time all you have to do is hit a key. A little bit faster eh? Below is the final image. Compare the ruler on the original and finished image. Seeing this on the web doesn't do this technique justice. Don't be afraid to try this one at home! I hope this one helps you out someday. If you have any questions, drop me a line and I will try to help you out!

[brad_towery]

Thanks Jeff! I had read about the 10% "trick" but having an action to speed things up will be great. Thanks for your time and effort on the tutorial.

[keithbales]

I like this idea, great way to blow up a crop to poster size.

Keith

[Throughmyeyes]

Very helpful tip indeed, just downloaded Gimp and I wonder if it can do the 10% trick also.

[snooze4592]

Terrific! Thanks!

[jbradc]

I have read about this technique before but never tried it. It is good to hear from someone that it works.

[Landis]

Jeff,
This is good, however I have learned to do it in 5% increments rather than your 10%. I have tried many methods of doing this and have found that the smaller the change, the smoother your image at the end.

If you have your "standard size" print you like to do from your camera, do the same as you have done here, but do all the individual steps to get to your size, maybe upsizing 6 or 9 times, what ever it takes, and write an action for that whole series and call it something like "RAW to 17"wide. Hit it once and you end up with your exact size without having to hit the action run button X times.

Thanks

[Ralph Newman]

Okay this works for increasing size, what would you recomend for decreasing size. Most of us posting to the web star with pictures up over the 2000x2000 and end up with 640x480. Till now I have been doing it in one hit with a slight USM at the end. Should the reduction be done in smallers steps?

[CathieT]

Thanks Jeff!

Cheers,
Cathie

[photoshopabuser]

I usually go to Image/Size and uncheck the Resample box and set the resolution to 72, and click OK. I then go back to Image/Size and check the Resample box and enter a value of either 600 pixels for landscape mode or 500 pixels for portrait mode.

Finish it up with a bit of sharpening and you are on your way. Don't forget to sharpen on a duplicate layer so you can fade that layer if needed. Sharpening techniques isn't that bad of an idea for a new article now that I think about it......

[photoshopabuser]

Thanks everyone for the kind words!

Landis, if that works for you.... cool. I haven't played with RAW files yet so I'm not sure about that at all. I have just gotten used to the 10% and have come up with some suprisingly good prints.

[aweller]

Thanks Jeff - like this too. Now I have to start a thread on getting billboard size prints. Anyone done this? (ie. what is the best print quality at reasonable cost?. I want to do a 1.5 x 2.6m poster from some stitched images I have created.

On this super-sizing method:
How do the results compare to using the raw convertor in Photoshop CS and selecting the size that is bigger than the native size? ... I'll give it a try soon if noone knows.

And for those asking, on reducing size, photoshop is a lot better at that (it is removing information after all) than it is at increasing the size.

I suspect there is some quality benefit in reduction by exact multiples of pixels (ie. 1024 x 1024 down to 512 x 512) using Image size, and then using canvas size (in pixels to exactly the size you want).

I keep a calculator handy to do these sort of calculations.\

Ciao,
Andrew who still can't get Stuart E to tell him where he got his hot shoe level in Australia!

[Ralph Newman]

well Andrew, I am not Stuart, but have a look at these links. One is a PDF price list file with a level available at $70. Australian.

http://www.mastery.com.au/qt/shd-qt/...rrp_160104.pdf

http://www.mastery.com.au/

http://www.mastery.com.au/qt/qthw.html

then there is this link that has a picture in it.
http://www.mastery.com.au/qt/hw-qt/p...s.html#monobbl

[aweller]

Thanks Ralph heaps. Now back to the original question:

I did this quick and dirty comparo.

Used the raw conversion interpolation on Photoshop CS (one step to 6144 x 4096 - it's largest size) for my "Largest" Canon Raw file.

cropped this 800x400 from the middle of it.

Compared this to the supersize method proposed.

The only scope for finessing the comparison would be to understand more about the impact of sharpening in either method. I used a smaller radius (0.5 px vs 1.0 px) for the smaller photo.

I think I will be doing the Raw conversion interpolation in future ... you decide for yourself.

Ciao,
Andrew off to buy his hot shoe level.

[Ralph Newman]

Get one for me while you are at it Andrew!! Will send you the delivery address if you need it!

[neilp]

hmmm interesting technique...

does this only work with photoshop???

I'm curious as to how this is different to just doing the single one step large resize, in other words if you are going from a small image to a large one then there's no way you can fill in the missing data...

can anyone post an example of a small image and a crop from the resized results; Chief Editor
it would be great if you could include a crop of the feeler/antler things on your butterfly to show us the detail, and also a crop of the original for comparison!

Thanks!

Neil.

[Ralph Newman]

Neil, I can see how it would work better using the step method but would also like to see a close crop of the same photo, one using 1 step and one using multi step both unsharpened to see what difference if any. There are programs around that plug in to PS that will do the resize for you, I believe there is a complicated mathimatical equation behind all this too big for my brian to comprehend.

[neilp]

There's always some maths behind these things! I'd be interested in the theory if anyone knows it.

Cheers,

Neil.

[ap.]

Elves. Tiny little elves living inside Photoshop. They can only count as high as the fingers on their hands, so 5 or 10 work best. True!

[snooze4592]

Elves. Tiny little elves living inside Photoshop. They can only count as high as the fingers on their hands, so 5 or 10 work best. True!

And they eat chocolate chip cookies.

[aweller]

Guys,

It's called "interpolation" ... it's not really that complex. Ie. at its simplest level imagine once an images is upsized by 50%. It has 2 adjacent pixels both with the same value x. When resized these two pixels need to be represented by three pixels. it has a value x in pixel 1 and a value x in pixel 3. It guesses that there should be a value x in pixel 2. That is the simplest case that only takes a few elves

There is an "algorithm" (or formula that is then converted to a computer program) called the Bresenham algorithm - look up Bresenham on google - 12,800 references!

All it is trying to do is decide on the basis of the colour of a pixel, and it's neighbours, what should be the colour of the pixels that replace it and them in the resized image.

There is another process called anti-aliasing which is the process of tricking the eye to think there is more detail in a group of pixels than there is by twiddling with the individual colours in each pixel to make lines LOOK less jaggy etc. Even though when you look up close, the real story is a lot more evident.

These things work together in the sophisticated editing software like Photoshop, or the sophisticated in-camera imaging systems that do this sort of thing depending on the settings you have.

There you go ... if you want to dive deeper, enjoy the prospect of becoming a geek.

Ciao,
Andrew, happy to let the elves work their magic.

[neilp]

Hey Andrew,

Thanks for the information... I hadn't heard of Bresenham before... that's a new one for me, I think I'll take a look. Hmm here's a site all about what the elves do!

http://www.cs.helsinki.fi/group/goa/...s/bresenh.html

I understand the idea of interpolation for englargimg and anti-alias for reducing sizes... what I don't yet understand is how a single large resize (with interpolation) is different to many small enlarges...

Any ideas?

[aweller]

The difference must surely be a difference of perceptions and the effectiveness of the different algorithms used for the type of detail in the original photo.

The resultant images may be more pleasing, but less sharp, and less acurate.

Interpolation is the process of filling in the blanks ... any iterative process should surely be less acurate by definition than a direct process - even though by nature it may be less pleasing to the eye. The addition of a similar level of blurring to the one step image may produce the same aesthetically pleasing result.

rgds,
Andrew.

[samtimes]

there is a free plugin that will give you a little more flexibility using this technique. I used to go the action route before and since I found this plugin, I'm using this instead:

Stairstep Image Size

___________
sam | ddoi

[Ralph Newman]

Mike, you have one steep learning curve ahead of you. It will be exciting so long as you are able to commit some time to it all. A little PS7 each day will be a lot better than a lot once a week. The biggest thing is remembering what you did last time and where it was.

[Mperko]

http://www.imphotography.com/downloads/ssimagesize.htm

Free plugin for Photoshop that does that nicely for you. You put in the desired image size, set the number of steps, and set the % per step, and watch it go!

[Ralph Newman]

Great tip Matt. I just loaded the plugin and tried it, works very fast so one assumes it "knows" what it is doing. Seems very much the same as described here. Nice to have an automated action. Thanks for the tip.

[samtimes]

heyy! I said the same thing as Matt 2 posts before him, but he got thanked only and not me!

oh well, I think I'm not welcome here.

packing my bags now

sam

[Ralph Newman]

Boy He is right!! So you did Sam, and I totally missed that post, don't know how, I must apologies. NOw leave those bags alone okay, we don't allow sulking on this site! To be fair, "great tip Sam". Boy don't you just hate copy cats Sam? Bet Matt was the only one that spotted your link and decided to repost it????

[Mperko]

Must have been posting at the same time I guess. There was no mention of that plugin when I posted.