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Doug Griffith
08-29-2008, 1:24 PM
Hi All,
Expanding on both Frank and Rodney's efforts to make it easier to convert files for engraving, I created a Photoshop script that should make it even easier. For the full scoop, check out the originating thread at:
http://www.sawmillcreek.org/showthread.php?t=91076

The script(s) are located here:
http://www.dogcollarlabor.com/smc/

I also put Frank's actions there just in case they get lost.

If anybody finds any problems let me know. I can also update it to accept more parameters, etc...

Cheers,
Doug

Frank Corker
08-29-2008, 4:35 PM
Doug I like the script but I ran an identical picture through and there are some variations. Only very subtle in the contrasting, your script removed detailed from the whiter areas. On my action script I added slight changes on initial load up but it is definitely making a difference.

greyscale
image sized to 300/400/600 (Alt+Ctrl+I)
Adjustments/ Auto Levels (Shift+Ctrl+L)

then I did +25 on brightness and contrast
then the unsharp (twice 3.5 then 1)
bitmap
invert

The reason why I chose steps 1,2 and 3.
(1+3) Even when adjustments have been made to a picture before being saved, quite often the image isn't quite right after being converted to greyscale and the shades of grey are different to the shades of colour. What might be suitable to make a colour picture is fine but it doesn't necessarily make a good greyscale photo.
(2) The image needs to be made the correct size before the image alterations are done.

I've never actually used that method, a java script, but I do like it. I'm not sure how long it took to create or if it would be difficult to make the alterations. Also in Actions the 'Actions' panel always remains open, is there a specific one for the java scripting?

All this is positive Doug, in no way a criticism - it's what sharing wealth is all about and anything that makes things easier for anyone using either method is a good thing and I'm all for it.

.

Frank Corker
08-29-2008, 4:55 PM
I wonder if I might hijack this post a little and expand on what we are trying to achieve. I would love to know how Photograv got such an even greyscale picture as the one they used in all of their samples? Obtaining this level of overall uniformity is probably one of the biggest hurdles that we all face. I refer to the one attached if nobody has it.

I think if the guys who are excellent in graphics might be able to direct us into an almost foolproof way of achieving that we could all be better off. So let's hope we can generate some good responses.

Doug Griffith
08-29-2008, 5:02 PM
Thanks Frank

Scripts in Photoshop are pretty tricky but now that I've gut the guts to it nailed down, changes won't be too involved.

I followed the actions exactly. Your last post mentioned "then the unsharp (twice 3.5 then 1)". The actions provided does an unsharp at 500/3.5/0 then 150/1/0. Am I missing something?

Thanks,
Doug

Doug Griffith
08-29-2008, 5:07 PM
I wonder if I might hijack this post a little and expand on what we are trying to achieve. I would love to know how Photograv got such an even greyscale picture as the one they used in all of their samples? Obtaining this level of overall uniformity is probably one of the biggest hurdles that we all face. I refer to the one attached if nobody has it.

I think if the guys who are excellent in graphics might be able to direct us into an almost foolproof way of achieving that we could all be better off. So let's hope we can generate some good responses.

In Photoshop I'd say it's all about adjusting curves. Levels would be the next best choice. The problem with curve adjustment is the difficulty in mastering. I'm going to look into scriptability of curves whaich might make it easier.

Cheers

Frank Corker
08-29-2008, 5:12 PM
Thanks Frank

Scripts in Photoshop are pretty tricky but now that I've gut the guts to it nailed down, changes won't be too involved.

I followed the actions exactly. Your last post mentioned "then the unsharp (twice 3.5 then 1)". The actions provided does an unsharp at 500/3.5/0 then 150/1/0. Am I missing something?

Thanks,
Doug


No Doug, you have that part all perfect, it's just the beginning bit up to +25 for brightness and contrast that needs to be changed. I'll be glad of it if you can post it when you have it.

Doug Griffith
08-29-2008, 6:08 PM
Hi Frank,
I moved the image sizing to after the grayscale conversion. Maybe that will do the trick.

I updated the files on my server.

Frank Corker
08-29-2008, 6:52 PM
Nope, still getting the same result. Have a look at the two images below. Focus on the writing and the hair.

Doug Griffith
08-29-2008, 7:36 PM
OK. Now I'm on a mission.

Damon Hoxworth
08-29-2008, 11:36 PM
Fellas,
Don't mean to jump in unannounced, but howdy.

I've used Photoshop and its ilk for the past number of years and in all my dealings of converting color photo to greyscale image I have never used the default Image-->Mode-->greyscale conversion alone. I believe that it is this use that is creating the need for more refining work.

I really don't have time to get into specifics (be back next week for sure), but check out Channels to make adjustments. The idea is that instead of just a single greyscale layer you have several channels Red Green Blue & Greyscale to make adjustments. So make 2 copies of your original RGB file. Convert one of them to Greyscale using PSs Image-->Mode-->greyscale. The second, keep rgb, but select the Channels pallette, and for each (RGB) composite layer, select all and copy onto the greyscale copy you have open (these channels will all be greyscale representations of the RGB image). Make sure to name the copied layers appropriately Red/Red et al. After you have them all over (now 4 layers in total R,G,B & greyscale) and make adjustments to each individual layer to get your desired result.

See you next week. Happy Labor Day and Labour Day Eh!
damon

p.s. There are other ways of doing this as well which we could get in to when I get back, check out using an adjustment layer on a working copy of the rgb image, shoot for 100% on values.

Frank Corker
08-30-2008, 4:37 AM
Look forward to hearing about it Damon. I have used the desaturation method that you are talking about to find out which one of the colours is affecting the picture more but it's quite a dragged out method. That said, if you can show us the way to getting nice even grey colouring, I'm listening.

Clyde Baumwell
08-30-2008, 7:25 AM
I'm jumping in now.

In Photoshop (pre CS3) there are many ways to convert to greyscale like Damon mentioned that will give you much more even tonality. Probably the best way is to use the Channel Mixer found in adjustments or layers (I prefer using layers for non-destructive editing). Just click on monochrome at the bottom of the dialogue box and go at it with the (RGB) channel sliders. Remember that what you see on your monitor is not always what will print, but should be sufficient for this purpose. You can adjust each channel individually to achieve the results you are looking for.

Another, often useful way, is to convert to LAB under Image>mode and adjust what is called the "lightness" channel and convert to grayscale from that image after either a curves or levels adjustment. (the a & b channels will be automatically discarded)

I don't use one method exclusively because no 2 images are exactly the same.

I suggest resizing before converting-not sure how much it matters for laser engraving photos, it just makes sense to me.

After I got CS3 I have changed my workflow. In CS3 there is a black and white layer adjustment that is as powerful as it gets and also I can do it in Adobe Camera raw (not only raw files but jpeg and tifs) - they are both non destructive conversion methods that offer the most flexibility.

sorry for the rambling post
clyde baumwell

Doug Griffith
08-30-2008, 1:08 PM
I look forward to learning more and better techniques when working with grayscale images in Photoshop. The more knowledge the better. I've always applied levels and curves to channels.

Regarding the "Gold Method", in my opinion print is far more receptive than laser etching when it comes to fine tuning. In the end, lasers are just firing all the same sized dot spaced accordingly.

I modified the "Gold Method" script to:
1) convert to lab mode
2) delete a & b (scripting doesn't do this automatically)
3) convert to grayscale
4) change resolution
5) apply shadow/highlight operations
6) apply autolevels (to remove loose white artifacts)
7) apply unsharpmask a few times
8) flip & invert if needed
9) convert to bitmap

I think it might be a good idea for me to add a few adjustment sliders.

The difference I found between scripting and actions is that brightness/contrast does not work the same between the two. In fact brightness seems to be buggy when scripted. I opted for shadow/highlight instead and seems to be less destructive to the image and produce better results.

The files on the server have been updated.

Cheers,
Doug

Doug Griffith
09-01-2008, 9:36 PM
New and improved script!!!

Better conversion methods plus you can now adjust brightness and sharpness as well as invert and flip on the horizontal axis.

I updated the script and put it online.
http://www.dogcollarlabor.com/smc/DOWNLOADS/GoldMethod.zip

It can be ran from the scripts menu or double clicked from the desktop.

Hey Frank,
Your PM box is full. I tried sending you a message.

Cheers,
Doug

Frank Corker
09-02-2008, 7:57 AM
Sorry Doug, seems I'm a popular guy! Just downloaded the new script, fantastic! Works like a dream. For those of you who haven't tried it, you really should, there are quite a lot of additions to the original and it is so easy to use. Well done to Doug for his hard work. It's paid off.

Doug Griffith
09-02-2008, 8:50 AM
Thanks Frank,
We all contribute as we can. I just hope it doesn't get lost in the thousands of threads.

Doug

matt heinzel
09-02-2008, 10:27 AM
One sizing Question. When I make a 8x10 image at 300 dpi, I then run the script on the file at 300dpi. When the image is done it is now smaller then 8x10. Why does it resize?

Doug Griffith
09-02-2008, 10:33 AM
Hi Matt,
I just ran an 8 x 10 with no resizing issues. Are you sure the display window is not resizing due to the resolution of your screen? If that's not the case, can you check the image size in Photoshop and let me know what it resized to?

Thanks,
Doug

matt heinzel
09-02-2008, 10:49 AM
1.92 x 2.4, which is proportional to 8x10. I am not sure why it would do that to me.

Doug Griffith
09-02-2008, 11:00 AM
One more question before I dive into the code. Are you using metric units?

matt heinzel
09-02-2008, 11:18 AM
No set up a blank 8"x10" document at 300dpi. Then I dragged a picture into that document and saved the file. Then I ran the script and it resized it down to that size in inches also.

Doug Griffith
09-02-2008, 11:26 AM
I just sent you a PM.

Frank Corker
09-02-2008, 1:58 PM
Matt when I have resized and saved the image does not alter. The screen picture will alter but the finished picture should be exactly the same dimensions.

Doug Griffith
09-02-2008, 2:09 PM
I figured out it was a CS2 vs CS3 thing. CS2 needs the preferences temporarillary set to pixels. I made adjustments and it now works in both versions. The updated script will be uploaded to my server later today.

Cheers,
Doug

Doug Griffith
09-02-2008, 3:49 PM
After looking into it, the script will only work in Photoshop CS2 & CS3.

Cheers,
Doug

matt heinzel
09-02-2008, 4:01 PM
Frank has been working on this with me. Seems the script worked in cs3 and I have cs2. He fixed it and now it works for me as well.

Frank Corker
09-02-2008, 4:21 PM
Frank has been working on this with me. Seems the script worked in cs3 and I have cs2. He fixed it and now it works for me as well.


Doug! Doug has been working with you and fixed the script. Doug's the genius behind this one.

matt heinzel
09-02-2008, 4:31 PM
Ha thats what I meant Doug not Frank! whoops! Sorry Doug!

Doug Griffith
09-02-2008, 10:38 PM
It's been said I'm frank but this is too far!!!

I uploaded the latest and greatest. I'm labeling this as version 1.

Cheers,
Doug

Jon Scrivano
09-11-2008, 8:05 PM
Hey guys!
This is really rad script. I'm kinda brand new to the whole laser engraving and doing a bunch of experiments. So with that said, I already have PhotoGrav. Would it be best to stick with that? Or could I get a better picture quality with this script?

Doug Griffith
09-11-2008, 8:47 PM
I would experiment and see which works best. Let us know how things work out.

Cheers,
Doug

Dave Yanke
02-17-2009, 1:40 PM
This thread needs to be a "sticky"!

I was sent here by Jack Harper. After getting frustrated waiting for ULS to release their new driver which has photo enhancements, I was ready to fork out cash, a tight commodity in the current economy, for PhotGrav. This appears to at the very least save us some $$ waiting for ULS. Heck, as I play with it, we might not need to new feature in the driver like we thought we would.

Thanks to Doug for the script and Frank and all for the input.

Doug Griffith
02-17-2009, 1:55 PM
Thanks to Doug for the script and Frank and all for the input.

You're welcome.

This used to be in the suppliers sticky which for some reason disappeared. It would be nice if that whole thread was brought back.

Cheers,
Doug