Hello... Well this morning The render got done for the Renderosity Cover Contest and I did postwork and I decided to see what it would look like as CMYK and boy was it real dark....And anyways to make a long story short I saved when I didnt want to save so I have to re-render(Took 40Hours this last time...I am rendering at 2550x2984@300dpi) now it will get done the morning of the 9th (I hope)and I will do the Postwork and save as A tiff file but in CMYK format like They want and I will upload the 640x749 @72dpi ...Now I went back into the scene and Lightened it up and re-rendered a scene this morning then saved as CMYK and looked at it and it looked like the original did when I first did it before I did the adjustments for CMYK....How come a normal lit scene went and turned extremely Dark?I saved with the LZ2 compression? How should I go about setting up my already dark scenes for Printing? Should I use the Gamma Correction Feature,Seems when I use that feature everything gets washed out especially all of the shadows? For all of you GURU's out there how would you go about this?Especially if you wanted to do Movie Poseters? Do I need to add more lights? Help is there a tutorial out there or do I need to do one for the general Brycer community?

If you are using Photoshop 5 or newer you have to set your color profiles to display the image properly. Photoshop adjusts the image color to display properly on screen for you, and the settings from the factory are usually wrong. Those settings are in the file menu. To get a rough calibration, print your image in RGB, convert to CMYK, and adjust your color profile to match the print as closely as possible. If you don't have a printer, then adjust the CMYK profile to match what the RGB was and hope for the best. Color correction is a pain. If you are using a Mac, calibrate the ColorSync Control Panel/Pref Pane as well (well first, actually).

Oh, and never compress files unless you absolutely have to. That LZW compression can introduce artifacts into the image, so unless you absolutely have to, turn it off. You can always stuff or zip your files after you save them to conserve space.

Thanks for the heads up...

Another good rule of thumb is to adjust your colors and levels in RGB mode to lighten etc, then change to CMYK mode, adjust your brightness and contrast to about 7contrast, 15 brightness to adjust for the gamma diff from mac to windows and maybe adjust hue and saturation. In PS 7 the cool thing is to use the Proof set up> Windows Preview, mac preview etc. But overall I would work out my levels and curves in RGB mode first before converting to CMYK. Today's printing is sucha nightmare OYEEE!! LOL!!

I asked this in the Magazine forum; Can I do everything as normal; render and save as .bmp post-work in Photoshop (7) get it just the way I want it... then convert to CMYK, and then adjust the levels agin to try and imulate what I had beforeas RGB? Will this work? AgentSmith

Well, that won't work, since it looks exactly the same in Photoshop as my RGB version, but when I look at it without Photoshop, it's all dark... So...if anyone knows of a webpage "CMYK for complete freaking Dummies"... I would appreciate it, I'm starting to get that same level of confusement as when I had tried using Vue... Not that I'm going to win, I can't even place in these things, lol, but now I want to know how to do this properly. AS

PS 5.5 has a curve tool. Should be worth playing with.

It can be a real pain converting to CMYK - and the things that usually suffer the most are rich blue skies etc. Renders from Bryce often tend to appear darker, and more muddy in Photoshop than Bryce, and one of the first things to do is try the AutoLevels function. The results are not always desirable, but you can fade the it down immediately after applying it. But the point is that the levels will have been pushed to their highest with the gamma, and you have an idea of the colour/contrast range in your pic. If you are going have the image printed via a particular company/press type, ask them for their own colour profile files, which should convert your RGB into their specific printers range. It's always best to work on a copy of the original render, and try different methods to achieve the final result that you can compare. Once you become experienced as to what colours are most likely to suffer the conversion, you are often better to convert to CMYK immediately (or use the proof setup preview in PS) and do all you contrast and colour tweaks in the colourspac that the image will be printed in. I use LZW compression all the time, and I have never noticed artefacts - it is supposed to be lossless compression!!?

AAArrrrgghhhh, I just looked at my renderosity cover entry in tif using a different package to pshop and have exactly the same thing, my carefully made image looks pants :-(

Attached Link: http://www.renderosity.com/messages.ez?ForumID=12366&Form.ShowMessage=1185799

There's a much easier solution, though, than slaving over test-prints and re-renders. Hope this helps you, Foleypro, there's a lot of What-you-see-is-what-you-get software available, the best one I've found is Colorific for Windows. Any professional setup not using at LEAST Colorific is, well, amateur. (A big "screw you!" to Kinko's!) It creates color correction profiles for monitors, and standardizes output for both print and monitors. It will process all of the math necessary to convert RGB to CMYK, internally, and with little or no intervention from the user. I've been using it for years, over several platforms, and countless monitor/graphics card/printer setups. Flawless. Give it a try, if the Renderosity printers aren't using it yet, tell them to get on it.

Oh yeah, COlorific is similar to the ICC engine in Photoshop 5 and later, I assume the two use related functions or something. Just an idea to help save some time, maybe...

Thanks all... Where can I get Colorific? I am re-rendering the scene anyways I want to see if this will help by lighting up the scene way more then normal without useing the Gamma Correction feature(Washes everything out too much) I use PSP 7.04....

I got Colorific with my vid-card.

Attached Link: http://www.colorific.com/c1.htm

Don't want to muddy the waters here too much, cause I am interested in the answer. When I compare between the CMYK output of my epson C82 printer under a good halogen light and the image on my monitor (RGB), it is very close! (I use PhotoPaint 9 from Corel). I have not converted to CMYK (unless it does it on the fly in the background with the print). Thus my basic question, is it really necessary to do so?

Incardine, it's only necessary to convert to CMYK if you are sending your image to be printed on a press. If you leave it in RGB mode, sometimes your image will print in black ink only.

Well the render is at 85% which is actually at this time 5% faster then last time? Will keep you all informed....

Holy shit! that's some difference. I don't use Photoshop, but I think there should probably be a preferences or options setup option under file.

Thanks all.... And yes there is a big difference when switching over to CMYK saveing the file as a Tif with CMYK then bringing back into your favorite Paint program and placeing side by side,There you will see a massive difference.... Wait until I get the main Render I am doing for the Cover Contest done and posted then I will be posting in my gallery both renders side by side and I will be doing a Tutorial for Bryce on "How to set up your scenes for Printing A.K.A...CMYK" Well I got until tonite so I need to go in and do some Postwork on the render and will check back in tonite and hopefully have a render to upload for the contest,My main Problem is that I am rendering at 2550x2984 @300 dpi BUT it is alot easier to do postwork on the pics at this size tho...

I rendered my cover entry at full size too, it does indeed make post work easier, I used RGB in post so that I could use all the pshop filters, I have the same problem with my cover entry as with the image above. The CMYK TIF file looks great in pshop and pants in everything else :-( Note with the above sample all I've done in this session of each program is load the same CMYK tif file.

I've got the same problem in Corel Photopaint 8, the CMYK is darker and bluer (my purple sky is now all blue). When I converted to CMYK it said something about using a Generic offset separation profile to do the conversion. Not sure if there are any other profiles to use or how to set one up.

My feeling is that the darker image that comes out from a CMYK conversion is meant to be printed, not viewed, and should print properly as is. I just had a normal RGB image printed on a commercial printer it came out too light and washed out.