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The Artblog.net Guide to Shooting Totally Adequate Digital Images of Your Work

Post #868 • September 12, 2006, 8:40 AM • 31 Comments

Recently The Next Few Hours announced a workshop offered by LegalArt on how to shoot digital images of your artwork. Alesh went, and reported that, basically, it sucked.

If I wasn't a photographer and a photoshop geek myself, my take-away from this would have been that it's impossible for me to take a decent picture of my work, and I need to get a pro to do it. It's really a shame; someone should do a workshop like this and give artists information they can actually use.

No surprises there - LegalArt also just sponsored an emerging artist award that reeked of conflict of interest on a scale that put it slightly above a harsh bleu and just under yak entrails.

Friends, it is indeed possible. Without further ado, here is the Artblog.net Guide to Shooting Totally Adequate Digital Images of Your Work. Hope it helps.

Comment

1.

Noodles

September 12, 2006, 9:50 AM

Thanks for the guidance jeti geek master, but perhaps you could have offered this info without the snarky comments about legalart...you have make it exceedingly clear that you despise EVERYTHING about Miami, from it's artists, it's cultural institutions and it's workshops. That's Okay, But tone your hatred down, it doesn't become you.

One more thing a TRIPOD is a very important ingredient for taking nice pictures.

2.

opie

September 12, 2006, 9:58 AM

Thanks. This is very generous of you. I do some of these things but there is lots more I can try & I am sure that will help. Also I expect some of our techie readers will offer further advice.

3.

opie

September 12, 2006, 10:02 AM

Noodles, Franklin's response to LegalArt may be colorful but it seems to me merely a reasonable reaction to something he found very inadequate.

You can disagree, but It was not "hatred" nor should it be ascribed to "despising everything about Miami". That's just silly.

4.

wwc

September 12, 2006, 10:09 AM

Thanks Franklin for the good advice about getting digital images.

I sometimes just scan the flat thing in pieces on my little flat scanner, then piece them together in Photoshop. I end up with a full size high-res version of the work. It can be a hassle though...

5.

Franklin

September 12, 2006, 10:22 AM

Noodles, I'll upgrade the importance of tripods in the essay. You should learn the difference between hatred and criticism. Miami has a lot going for it, notably one of the best cultural affairs councils in the nation and some excellent artists. There's also a lot of ridiculous crap. It's not all one or the other.

Opie, you're welcome, and any techie input into this would be great. I've been meaning to record my thoughts from years of teaching and they may end up as similar pages.

Wwc, I've tried that too, and it can work unless the paper has texture, which shows up in the image as severe noise and moire. It's probably fine for photos and other similarly flat papers.

6.

alesh

September 12, 2006, 11:28 AM

Wow, thanks, Franklin!

I haven't read the essay, but will very soon. Super cool.

Not only is having an artist a much better suited to providing this informatino to artists then a digital imaging geek, but I suspect that an online how-to reference is more useful in the long run (and possibly even in the short run) then a demonstration/lecture. Perfect.

7.

Marc Country

September 12, 2006, 1:35 PM

Shouldn't that be, "The Artblog.net Guide to Shooting Totally Adequate Digital Images of Your PAINTINGS"?

I'm a big fan of using the sun for taking pictures of my sculpture, too, but I'd recommend a cloudy day for that (the 'soft-box' effect).

I'm surprised at how much photoshop-ing you do on your images, Franklin, especially the "Free Transform" bit (in lieu of just shooting the work straight-on in the first place).

Be careful with that clone tool, folks... sometimes it can have some pretty obvious effects...

8.

Brian Duey

September 12, 2006, 3:46 PM

Thanks for the info on shooting artwork. I have always struggled with that until I bought a scanner.

9.

Franklin

September 12, 2006, 4:39 PM

Marc, want to do a 3D version of the tutorial?

I've found that you can either kill yourself setting everything up square, or just yank it around in PS, in which case it just has to be close. If you're shooting outside it's a big help.

10.

Jack

September 12, 2006, 6:54 PM

Well, I'm sure this is hardly news, but I know never to use flash when photographing sculpture, even if the camera wants to do it (which it almost always does indoors). Sculptures don't like flash; it startles them. Suppressing the flash mode has often resulted in unexpected and sometimes very interesting effects. My favorite was a picture of Canova's marble The Three Graces, which somehow came out with a pale coral flesh tone in the figures. It was not true to life, but it looked delicious.

11.

Hovig

September 12, 2006, 6:59 PM

Best ... art-related ... blog entry ... ever.

Coincidentally, yesterday I threw my camera aside in disgust and had three drawings scanned by a local print house (1, 2 and 3). It cost about $17 each ($2 per square foot for an 8-bit [black and white] scan; each piece being 30 x 40 inches), plus a few bucks for burning them to a CD, but I needed high quality images since I'm thinking of making some printed materials from one of them.

12.

alesh

September 12, 2006, 7:16 PM

I'm really really glad you did this, Franklin. Your instructions are solid and intelligent (i learned a couple of great new things), and for something so important, I don't think anything this good exists anywhere else on the web.

Some quibbles/observations/tricks:

* A DSLR is the perfect thing to use, especially if you have a fixed lens, but with a little experimentation, any 3 megapixel or more point-n-shoot should get you close. It will just require some experimentation and tweaking (especially as concerns the autofocus; with some cameras the center point has to be pointed at a sharp vertical line while half-pressing the shutter).
* I couldn't agree more about the natural light; direct sunlight and indirect/overcast sunlight both seem to work pretty well for 2d work. A special consideration is when shooting a number of similar pieces, or pieces with delicate color, or pieces where the paper/bg is visible. In this case color balance becomes very important, and it would be worth getting a grey card and including it in the frame. You can then point the middle color picker on the photoshop level's dialog at it, and it SHOULD make all the pieces match.
* I've never used a polarizing filter . . . i imagine it can be helpful with glare on a painting in direct sunlight, but i'd be distrustful of color rendition (do you really want your blues that rich?). A UV is a no-brainer, especially with how I tend to treat my cameras
*The crop/free-transform trick is an absolute stroke of genius. My biggest problems have typically been trying to get pieces to look square with the Lens Correction filter.
* Having said that, lens correction (under filter->distortion) (and only in photoshop CS2, unfortunately) is an absolute lifesaver. I would caution that, in your example, the free transform maneuver will slightly change the height/width ratio of the piece. This is very bad, and is a good argument for getting the square issue as correct as absolutely possible on the camera. The Lens correction also relates to point-and-shoot cameras, which will be distorted. If possible, use them around the middle of their zoom range, where they tend to be truest. This means zooming in with the camera and getting farther away. The nice thing about point-and-shoot is that you compose your picture on an LCD, which with a tripod can get close to perfect results.
* The sharpen filter, especially, is a red flag that your original isn't so hot. is the only part I out-and-out disagree with. Digital cameras inherently capture images that are everso soft; you recognized that when you said "set Optimize Image to sharpness (its default is a little soft, for portraits)." This is all post-capture sharpening; whether it's done in-camera or in photoshop is irrelevant, except that photoshop gives you more control. In digital imaging, the focus of the lens is a necessary but not sufficient condition for an ideally sharp image. Which, btw, here's my instructions for using Unsharp Mask: (1) Set your magnification to 100%, (2) Fire up filter -> Sharpen -> Unsharp mask, set threshold to 0, (3) Set radius to 1 (or lower; some people swear by 0.3) (4) Slide the 'Amount' around until it looks right. Error on the side of too little, and especially look out for the characteristic 'sharpening halos.' 100% is a good place to start, though often it's way too much. If you're using anything over 200% I'd agree that a re-shoot under better conditions may be in order.
*The 45 degree light is much more important for pieces with surface texture. For photos and other perfectly flat images, the _evenness_ of the light is more important then the angle. Speaking of photos, never ever try shooting something that's framed behind glass if possible (maybe that's where the polarizer is a good idea, but for my money it's worth the effort to pull it out of the frame).
* I've never photographed sculpture, but Marc's comment re. overcast makes sense (might make sense for other work, too). I'd imagine that a nice backdrop is important for sculpture, and that ideally you'd want the camera and backdrop to stay still and rotate the piece for different POV's.

13.

opie

September 12, 2006, 7:57 PM

I know what you mean by the "yanking around in photoshop", Franklin. If you are not a real pro photographer Photoshop is absolutely necessary to get it fixed up. I have been using color correction, the skew tool, unsharp mask and other devices, like color range (helps get glare out), when necessary, ever since I started taking pictures of paintings digitally because I am much better at Photoshop than I am with the damn camera.

Good info, Alesh. Thanks. You are right about the sharpness; even under the best conditions digital cameras always seem to be a little soft. It isn't so bad for my paintings (it bothers me; no one else even notices) but as a photographer it must be galling to you.

14.

ahab

September 12, 2006, 9:35 PM

A really good resource, Franklin, almost surprisingly useful not least because you've offered it as shareinfo. You should really ride Marc Country to write up the "Totally Adequate Photos of Sculpture" corollary. I usually take photos I like well enough as pictures, but never do a very good job of documenting my other artworks, so thanks for the advice; although I'm no closer to knowing how to afford a dSLR.

Say four months from now I want to point a student this way, how will we find it? I don't see it in the special Artblog.net sections linked in the banner.

15.

alesh

September 12, 2006, 9:59 PM

I neglected to mention that I really like your new series of paintings. the piece you use as an example is particularly good; maybe my favorite einspruch. I read the discussion of it with some interest, though it didn't quite sit right with me. Since the woman facing us is drinking sake, I always saw the table (which extends to the left and right edges of the frame) as a bar, which makes the woman with the green tanktop a sushi chef, which seems a tad absurd. So it's a pleasant mystery to me.

opie~ trying to rephotograph a 20x24 c-print is a hell I wouldn't wish on anyone. The images on my site are just that, and I did them before I learned a lot of these tricks. More photoshop went into making them suggest the original prints then i'd even care to remember. Especially since my pictures invariably feature straight lines parallel, and close, to the edges.

Jack raises a couple of important points. Relevant to photography in general is that the use of flash should _always_ be at the photographer's discretion, not at the camera's. It's worth taking every single picture with and without flash for awhile, to learn the consequences. Also, since a photograph of a sculpture is a photo of an object, not a capture of an image, a certain amount of "artistry" can enter into that process (traces of said artistry are in the 45 degree light in franklin's photograph of his paintings, and are utterly absent from a photograph of a watercolor or c-print). Experiments with different types of light (ie direct sunlight, overcast, multiple strobes, softbox, etc.) are called for.

If you really find you need a DSLR, ahab, you can always rent one. Rockwell recommends renting a fixed macro lens along with it.

16.

Marc Country

September 12, 2006, 10:05 PM

The best thing about "Yanking in P-shop" rather than messing around with the real thing, is that on the 'puter you can always UNDO... My photoshop skillz are all trial&error learned, so I recommend that method highly.

"Levels" is definitely a beauty (not auto-levels), and can even be used to make decent images of some otherwise disasterous original files. "Variations" is good too, as it can easily correct any unfortunate colour cast the image may have. If you use this one a bit, remember to set it back to 'original' before you start on a new image.

I've learned the hard way about 'digital zoom'... just say no, and stick to 'optical zoom'.

Jack's right about avoiding flash for sculpture (and probably for pretty much any other art)... I'm a big fan of shooting in natural light on an overcast day... even light, little to no shadow... even a partly-cloudy day can work well for this, if you have the patience to wait for the clouds to move in front of the sun before shooting... this can be especially helpful if you're shooting large outdoor sculpture, since a grey day will look depressing if the sky features into the shot, whereas a partly-cloudy day looks cheerful, with big puffy clouds like at the beginning of The Simpsons.

As alesh notes, the background is indeed crucial in photos of sculptures, since you can't simply cut the sculpture out from its surroundings. Also, I believe that when people are looking at your images of sculpture, they are primarily looking at images, not sculpture... so, rather than trying to get the most descriptive shot, you're probably better off trying to get the most appealing image.

If the sculpture is not highly coloured, then set it in front of a coloured background. If the sculpture is small, you can rotate the piece (again as alesh suggests), keeping the camera, lighting, background constant (and thus get away with a small board propped up in your yard, pretending to be a prestigious gallery wall. Depending on the size, location, transportability... of the sculpture, you may in fact have no control over the background at all. In that instance, it is very important to visually consider background features and how they interact with the sculpture... do they interfere with the profile, etc... , and moe to elmnate problems. If possible, use a longer focal length and wider aperture (shorter depth of field) to achieve maximum blur of the background, setting the sculpture apart in crisp focus.

And always shoot lots of pictures... you can always delete fro free (I shudder to think of all the money in failed slides I've immediately thrown out over the years).

17.

Franklin

September 12, 2006, 11:01 PM

Hovig, makes my day. What he's describing is great for drawings, especially reflective ones that resist normal scanning.

Alesh, point by quibble...

The polarizing filter isn't distorting the color at all. It's making sure that the light only enters the lens from one direction. The blues become bluer without affecting the other colors, because the filter makes up for the fact that our atmosphere handles blue differently than every other hue. Plus, it cuts down on glare.

I'll look into lens correction. Thanks for the tip. For P&S, it sounds like the way to go. I'd probably try to hold out for the DSLR.

This is all post-capture sharpening; whether it's done in-camera or in photoshop is irrelevant, except that photoshop gives you more control.

Are we absolutely sure about this? I was under the impression it's post-capture, but pre-JPEG formation, which means that sharpening in the camera is worth doing. Thanks for the unsharp mask tutorial in any case. And I'm glad you like the recent work.

Ahab, how about a tutorial page? I'll set one up tomorrow.

18.

opie

September 12, 2006, 11:11 PM

I don't want to wish any more projects on you, Franklin, but it seems to be that a little more infomation-gathering and you could have a small instruction book which might sell a few copies.

Ahab don't point a student to it, just download the info and keep it on file. That's what I've done.

19.

Oak

September 13, 2006, 7:45 AM

CTC offers Polaroid 7000 slide burners for $495 plus shipping.

http://www.ctcsouth.com/p70001.htm

I bought mine a few years ago (and got the 8000, which , it turned out, really was not necessary). The software they provided works only under NT, but they appear to be offering other options now.

They attach to the computer using a SCSI interface, which is available now pretty cheap.

20.

alesh

September 13, 2006, 7:47 AM

And there are many more useful chapters in that book that pop right to mind, which F could write quite handily. How about the Artblog.net Guide to Setting up Totally Adequate Online Galleries of Your Work??

Franklin~ I've never used a polarizer, but "blues become bluer without affecting the other colors" is quite exactly what I'd have thought _you_ would have a problem with. I suppose if it looks good IRW then it's fine. I have a D80 in my near future, and I intend to get a CP filter for it to play with.

Right, theoretically you'd be sharpening the jpg artifacts. But as you've realized, at the 'fine' setting there hardly are any. The control that photoshop gives you outweighs the theoretical degradation.

I'm sure the guide will pop up prominently in Google for a number of related search terms soon enough; I wouldn't worry about finding it in the future.

21.

Franklin

September 13, 2006, 9:45 AM

Oak, slides are going the way of the dodo, and none too soon in my opinion. I'd regard a slide burner as a luxury expense these days unless I had to generate hundreds of them. You know that Kodak isn't making projectors for them anymore, yes?

Alesh, that gallery tutorial is a good idea. I'll get to work on it. Your homework is to find out whether that in-camera sharpen is a filter or a compilation mode off of the raw.

22.

Marc Country

September 13, 2006, 10:18 AM

I just tossed off an application for an Elizabeth Greenshelds grant, and among a few of their specific particulars is their demand for 35mm slides ONLY (no substitutes).

p.s. I had previously thought the grant was only availble to Canadians but, reading the application form, I don't see that written anywhere, so any of you "emerging" figurative artists out there may want to check it out... it's worth up to $12,500 CDN.

Maybe Jordan already got one of these? If not, he should definitely think about applying...

24.

Oak

September 13, 2006, 2:58 PM

Franklin you said you have slides made. I don't know how many you have made, but where I live it costs $25 each, so it does not take many slides to exceed the cost of a burner. The burners I am talking about are made by Polaroid, not Kodak, but you are right, they are no longer manufactured new. What you get for $500 is factory refurbished.

I firmly believe the old fashioned slide projector was and is one of the most cost effective pieces of visual equipment there ever was. The blackboard may be even more cost effective, I don't know, but together, the two are awsome and really hard to top. If you use a slide projector, you gots to have some slides.

PowerPoint on a fancy computer, on the other hand, is a bottom feeder, a turn off. I get sleepy everytime someone uncorks one of those over-hyped tech-ladened "multi-media" presentations.

25.

mfoto

September 13, 2006, 6:08 PM

no way you need to spend $800.00 on a digital camera these days to be able to take good images of your work. Also, the lens you mention [55-200] which is a zoom lens is not a good lens for taking images of artwork - you will do better with a standard lens - which will give you better depth-of-field. if you look at the image of your painting it feels flat - also longer lenses tend to start in slower f-stops.
for paper work that is flat a non-glare piece of glass does wonders. get a color reproduction guide or gretamacbeth color guide card to help you set white balance on your camera [pre-shooting] and in photoshop [post-shooting]. some thoughts.

26.

Alesh

September 14, 2006, 5:10 PM

Personally, I believe that the reason some organizations still demand slides (and some other are sometimes believed to discriminate against digital images, eg the South Florida Cultural Consortium) is to weed out non-serious artists.

I see the logic in that as much as I despise it, because it forces many people to jump through absurd hoops.

Having said that, most digital projectors are not of sufficient quality to match a good slide through a slide projector. A high resolution monitor is a different story, and even the resolution on the projectors is improving.

The problem with a digital projector is that you need someone who knows how to work them, or at least to set them up (and, often, to troubleshoot). And maybe that parenthetical remark hits on something too -- the other big problem with digital is that there are many many variables that the "art people" often don't grasp well enough to control.

But this needs to change, and with-it organizations accept digital images more and more. Gradually, all will come to.

27.

that guy

September 14, 2006, 5:43 PM

"The problem with a digital projector is that you need someone who knows how to work them, or at least to set them up (and, often, to troubleshoot)."

Yeah, how do you do that? Mine only projects about an 8th of the color that shows up on my desktop? Any quick fixes that you know about?

28.

Dan

September 19, 2006, 7:00 PM

Really nice guide, Franklin.

Some thoughts a week after the fact...

I second Alesh's points re: sharpening. A little Unsharp Mask is virtually essential for a quality image. And I'd never let the camera do the sharpening for me.

For one thing, it doesn't allow the flexibility to account for the different needs of different images. More importantly, sharpening should be the last operation you perform on a image. Because any resizing can undo the subtler effects of a previous sharpen, you may find that you have to resharpen when you downsample it for various media (something you want to avoid if at all possible, due to the increased destructiveness of resharpening).

Typically, I'll crop and color correct an image and save it, without sharpening, as a sort of 'base' file. I only sharpen when I'm saving final copies, resized for output. After all, you're going to want to sharpen a full-page monograph image differently than an image destined for a postcard-sized mailer (not to mention a 500 pixel image for the web).

Resize first, then sharpen.

And only sharpen once.

The Unsharp Mask numbers Alesh gives are in line with my experience. For print images I usually settle in at a Radius between 0.7 and 1.5 pixels or so and an Amount of 85-150% (always with a Threshold of 0). For web, I usually go with 0.3 pixels at anywhere from 50-250% or, if that's too intense, 0.2 pixels at 150-500%. In any case, be sure keep the filter preview pane zoomed to between 50% and 100% to give you an adequate proxy to judge from.

* * * * *

Also, a couple quibbles to add to the list...

First quibble: When Free Transforming the image, to avoid distortion you need to make sure that you square it to a rectangle that is proportional to your original image.

To do this, following Franklin's example...

... After cropping around the image, expand the canvas slightly to give yourself room to work

... Zoom in on the top left corner of the painting and pull a couple guide lines out from the rulers (Cmd+R to show rulers on Mac, Ctrl+R on Windows) to set a sort of crosshairs over the corner

... Zoom back out (try Cmd+0)

... Set the Rectagular Marquee tool to a Fixed Aspect Ratio (see the "Style" pulldown menu on the Options bar at the top of the screen) that matches that of the original (no need to do the math... just enter the original dimensions in the Width and Height fields)

... With "Snap" turned on in the View menu (toggle on/off with Shift+Cmd+;), pull a selection down from the top corner, completely enclosing the painting

... With this selection still active, pull two more guide lines to its right and bottom edges to complete the rectangle (with Snap on, these guides should snap into place)

... Hit Deselect (Cmd+D), turn "Snap" off (Shift+Cmd+;) and proceed as before, fitting the painting by a bit of trial and error to the box created by these guide lines

If you're doing any lens correction in CS2 to eliminate any barrel distortion from your wide angle lens (often necessary), do that before you Free Transform it. In fact, do that before you crop the image at all.

* * * * *

Second quibble: I'm not sure what leads Franklin to say that a PICT file is in any way "typical." PICT is a Mac-only format (for both bitmap and vector images) that I believe was primarily used for system graphics (pre-OS X).

Perhaps his service provider uses PICT, but truly typical would be a lossless TIFF. (N.b.: Using LZW compression on your TIFFs shouldn't affect image quality, but service providers often request the files uncompressed. Talk to your printer.)

Save your original and working files as either TIFFs or PSDs. If you need save your images as JPEGs, save these as copies and only as a final step. (High quality/low compression JPEGs are fine for printing, but saving and reopening JPEGs and saving them again can progressively degrade image quality as the files are recompressed again and again.)

29.

Dan

September 19, 2006, 9:06 PM

Also, a couple thoughts re: color management...

First, and I can't stress this enough, when saving in Photoshop always check the option to "Embed Color Profile" (except when saving JPEGs for the web, in which case this is just extraneous data).

If you understand nothing else of the esoterica of color management, understand this: it is the height of frustration to be on the receiving end of an image without an embeded profile... it's like being given a color by number without the color key.

* * * * *

Beyond that simple bit of advice, and getting a bit more complicated than is probably necessary...

Most consumer cameras will save to sRGB color space. This is fine. Higher-end models, including, I believe, Franklin's D50, may save into their own color space. More most purposes this should be fine. Depending on the nature of it, though, color correcting in this space could go a bit wonky, so it's probably best practice to convert the image to AdobeRGB before proceeding. (In any event, you may need to convert before sending it to print anyways.)

When you open the image, depending on your color preferences (Shift+Cmd+K), it may prompt you and allow you to convert it before opening. Otherwise, convert it manually:

In versions of Photoshop up to CS, go to Image > Mode > Convert to Profile... In CS2 go to Edit > Convert to Profile...

Choose "Adobe RGB (1998)" as your Destination Space, "Adobe (ACE)" as your Engine and "Relative Colorimetric" as your Intent, with "Use Black Point Compensation" and "Use Dither" checked.

If your photo starts out in sRGB, for most practical purposes you can probably go ahead and work with it in that space, but it may be best practice in some cases to convert this as well.

* * * * *

If you don't care about minor nitpicking that's totally beside the current point, stop reading now.

For the sake of clearing my own head, though, a clarification on this...

> JPEGs shoot into an RGB color space, intended for screen viewing. A purist will point out that the CMYK color gamut used in 4-color printing is larger (and hence you should shoot RAW and save as TIFF). This is true, but ignore it anyway. The CMYK color gamut includes combinations like C95-M95-Y95-K95, which is going to ooze out of the Heidelberg onto the floor.

This isn't quite right in a few respects.

First, color space (RGB vs. CMYK in this case) is irrelevant to file formats (JPEG vs. TIFF). These are two entirely separate issues.

Also, RGB is not just strictly for screen viewing—it's also for capturing and editing images. No one should really be working in CMYK. Print workflows typically end in CMYK, but only as a final step. All of the heavy lifting is generally done in RGB (though, if you really want a fun conversation, ask me about 16 bit/channel L*a*b* workflows).

Generally speaking, RGB gamuts tend to be much larger than CMYK gamuts (possibly clipping only the purest of cyans, magentas, yellows and blacks... e.g., 95%C, 0%M, 0%Y, 0%K). The AdobeRGB gamut contains virtually any colors you'd hope to print (especially printing on a 4-color press), and plenty you can't (particularly in the greens), which is why it is the color space of choice.

What the purists object to is sRGB in particular, which does clip some printable colors.

> Save For Web in PhotoShop forces the image into an sRGB color space, which is a subset of RGB. It constitutes a big savings in file size. I sometimes notice that a JPEG looks flat to me after going through Save For Web, but have not determined whether this is psychological or real.

From what I can gather, Save for Web doesn't convert to sRGB. If you're editing in another space, that could explain the flatness you perceive. Convert to sRGB before saving for web or sending to ImageReady.

Also, the particular color profile assigned to an image has absolutely no bearing on file size. Saving to Web saves on file space through compression, and by not embedding the profile.

30.

George

September 19, 2006, 10:19 PM

Dan's right about CMYK.

CMYK is ink specific and although there are some general standards, in general CMYK isn't really a color space, it's a separation space. Also, CMYK standards are different in different areas of the world, Europe uses the Din standard and in the far east "Toyo" is the standard. In other words their ink colors are slightly different and as a result the CMYK separations need to be different.

Once a file has been converted to CMYK, some of the original color information is lost and doing the reverse CMYK-->RGB does NOT revert to the original colors. What you see on screen when you view a CMYK image is actually an approximation of how it "might" look when printed. The CMYK color points are converted to RGB for display using a lookup table or profile.

One should always save archived files as RGB NOT as CMYK, if you need a CMYK file for a printer save it out separately but keep you original artwork archived as RGB.

I linked the articles in comment #23 because Bruce Fraser is on top of the ins and outs of digital color. If one really wants to dig deeper into the technology, they are a good place to start.

31.

Dan

September 20, 2006, 1:44 PM

One more quick note, following on George's points re: CMYK... then I swear I'm done.

Unless you're printing to a 4-color press, you shouldn't have to worry about CMYK at all. (And if you are printing to press, as George notes, you only convert to CMYK as a final step... and you should follow your printer's instructions at this point anyways—they may have a custom CMYK profile for you.)

If you're just printing to an inkjet, laser or dye-sub printer (including all of those sweet 7-color Epson Ultrachrome inkjets), chances are you'll be printing from RGB. In most cases, even if you send CMYK image data to one of these, they'll just turn around and convert it back to RGB on the fly.

And, as inkjet gamuts tend to be considerably larger than those of CMYK , unnecessarily converting to CMYK when printing to such devices only serves to unnecessarily cripple your color.

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