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Raw & Post Processing, Printing => Adobe Camera Raw Q&A => Topic started by: albedo13 on August 13, 2012, 12:55:42 PM

Title: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: albedo13 on August 13, 2012, 12:55:42 PM
I do mostly aviation photography, and in many cases it is simply impossible to avoid significant backlighting situations when you are shooting flying aircraft.  I have been trying to find new approaches (to me at least!) for optimizing these shooting situations as much as possible.  I always shoot in raw, and the approach I have used up to now has been opening an image twice in ACR via Smart Objects, processing it once to optimize the aircraft and let the sky go to heck, and then processing it the second time to optimize the sky and let the aircraft go to heck.  I then use Refine Edge in PS to combine the two layers so that I get the best sky and aircraft combination I can, and this seems to work reasonably well.

I have never used the ACR Adjustment Brush before, and have been watching a bunch of video training on ACR to try and improve my skills.  The presentation on using the Adjustment Brush for backlighting situations looked very powerful, but it seems like the ability to refine your areas of interest is not as powerful as you can get with Refine Edge in PS/CS6.  My question is this: are there any advantages to doing as much of this type of correction in ACR versus doing it after the image has been read into PS/CS6?  Are there any advantages to doing this in "raw" space in terms of more color space for trying to deal with such a wide dynamic range yet still maintain as much detail without introducing a lot of noise?  If so, does this outweigh the advantages made possible by the Refine Edge capabilities within PS/CS6?  Thanks, and please be gentle to the newbie questioner.... 

Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: Redcrown on August 14, 2012, 11:17:14 PM
Why has no one answered this?

Basic answer is yes, there are advantages to doing most adjustments in ACR instead of waiting until you get the image into Photoshop. Most, but not all, in my experience.

Doing tonal adjustments is better in ACR, especially in the new ACR 7 with the "2012" process with its highlights and shadows features. It's easy to test this. Take one of your images and fix the sky in ACR. Then pass another version to Photoshop without the ACR fix and try to do the same adjustment using Photoshop only tools. Be sure to pass the unfixed version to Photoshop in the ProPhoto colorspace to make it a fair contest.

Repeat with some midtones or shadows. If the adjustments are conservative you might not see much difference. But when the adjustments get more aggressive, the advantages of ACR will show up. For example, take a badly underexposed image and do a +1.5 exposure adjustment in ACR and then try that in Photoshop.

On the other hand, I find saturation (and vibrance) adjustments are better in Photoshop than in ACR. Primarily because in Photoshop you have access to more advanced saturation adjustment tools (Channel Mixer, LAB mode) and sophisticated saturation masks. But also because if you push the ACR Saturation slider to extremes, strange things can happen. Out of gamut colors are reached much sooner than with the basic Hue/Sat slider in Photoshop.

Sharpening and noise reduction is still highly debated. Some argue that ACR is better, some argue that Photoshop is better. Again, those arguments sometimes hinge on the ability to use advanced masking in Photoshop.

Which brings up your other question of the Adjustment Brush in ACR. Personally, I find it to be a crude and difficult tool to use. But that's because I've spent years masking in Photoshop, either by hand with paint brushes, or with other semi-automated techniques. I'm real comfortable with Photoshop "brush masking". Can't get comfortable with the Adjustment Brush in ACR.

Bottom line, I think your technique of making 2 or more ACR versions of an image and masking them together in Photoshop is a a good one. A lot of famous gurus advocate that approach. You get the best tonality from ACR and the best masking from Photoshop.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: Colorwave on August 14, 2012, 11:24:58 PM
I'm in agreement that the ideal way of playing to the strengths of both applications is to use ACR/Lightroom to process two ideal versions optimized for subject and background, then combine and mask them in Photoshop.  The masking capabilities of Photoshop just can't be beat, IMO.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: albedo13 on August 15, 2012, 12:46:40 PM
Redcrown & Colorwave-

Thanks for your responses, I was beginning to think I had inadvertently asked an especially dumb question!  I will continue with the 2 step blending approach.  In most cases, where the aircraft is clearly defined against the background, it is pretty straightforward to use that technique because it is easy to delineate the aircraft versus the sky.  However in some cases like the attached, I also would like to enhance the turbulence/plasma coming right out of the engines.  Since I am relatively new to using masks, I would have a hard time delineating the edge of the turbulence in PS.  Plus, from my experience it seems like the Clarity slider in ACR can really make this turbulence pop out from the rest of the sky/background. Is there an equivalent control in PS to Clarity in ACR, and can you make a mask to fit such a "nebulous" area of interest?  Thanks again!

Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: Rory on August 19, 2012, 11:02:25 AM
In photoshop try using a very soft brush and sharpen the masked area with an unsharp mask where the radius is very large, say 50-60.  Experiment with the radius and amount.  This is what clarity is doing in ACR basically.

Alternatively, this is the type of brushing that is easy to do in ACR/LR.  Again, make sure to use a soft brush, and just paint in the clarity.  Since you do not have any hard edges to deal with, you should be able to quickly get to where you want.

Hope this helps.

Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: kim on August 22, 2012, 08:17:24 AM
Answering your main question, I'd see the advantage of doing all the editing in ACR is that you have all the edits in one place so it is easier to make changes. The downside is, as you've said, the fewer features available in ACR for refining a mask. Your only real option in ACR is doing everything by hand, enlarging the image to 100%, then painting along the dividing line with a small brush and hoping that the edge looks alright.

I've shot aircraft in the past and having tried these masking techniques in PS and LR my overall advice would be - if you want to continue using PS, stick with the technique you've got. Only change it if you want to get to grips with Lightroom because it's in Lightroom that you really see the benefit of time-saving techniques like the Adjustment Brush.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: rambler44 on October 30, 2012, 02:17:50 PM
One way to pinpoint adjustments in ACR is to use the Tone Curve and the point system along the Linear setting. (In the Tone Curve window, select Point, and change the Curve pop-up menu to Linear)
For example, hold the Command Key (Mac) or Control Key Windows as you click on one specific area of the image.  That will add a point along the line that corresponds to the area you clicked on.  Moving just that point either above or below the main line (the line going from corner to corner diagonally) will either brighten or darken that particular area of the image where you clicked. More accurately it will not change areas with the same input/output values to change, get lighter or darker. 

If this has just confused you, just play around with the Command or Control Key clicking and you will see dots or points added to the line.  For further fine tuning use the arrow keys to move the points in the corresponding directions and keep an eye on the changes to you image.

Also, when using the ACR Adjustment Brush, you do not have to be too exact along the edges which I think is why there are two circular ring lines.  You can go outside the edge with the outer circle without painting the edge.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: Ken Bennett on October 30, 2012, 02:45:47 PM
I hope you will pardon my editing your image.

I created a duplicate layer, added an Unsharp Mask at 65/250/0, then made a layer mask and filled it with black to cover the USM effect. Then with a soft brush I painted in white where I wanted the effect to show through.

Of course you may want more or less of an effect, or something totally different, but this is one way of adjusting only the one area. It's even easier given the lack of a sharp line between that area and the background.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: rambler44 on October 30, 2012, 03:19:42 PM
Hi K B, My manual (PS Bible) suggests right clicking the Duplicate layer and then chosing Convert to Smart Object.
Then Filter to Sharpen to Unsharp Mask to apply the Unsharp Mask Filter to the Smart Object, and as you have suggested, "adjust the Radius to include enough of the surrounding pixels to detect the change and provide a smooth transition along the edges." !!

November edition of PS Magazine has a quick explanation of Smart Filters and Smart Objects, pp 48-49.

Albedo, here is a way to add some cool backgrounds to your planes:  Take an image of green trees, then goto Filter>Blur>Motion Blur and put in various "Distance" numbers, (pixels) eg. 150.  This will give you a nice motion blur of green which you can also set at an angle.  Then drag your plane on top of that using Free Transform (Command or Control T) to scale it to size.
Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: davidh202 on November 11, 2012, 01:19:28 PM
A very easy way of adjusting an image like this where you need separation of the sky would be to first do as much of your global adjustment in ACR to your liking, then use the graduated filter in ACR adjustment  to darken the sky which willl also affect some of the plane and trees. Then go to the adjustment brush with auto masking turned on, and use the brush with appropriate feathering to back off the areas of the plane and trees that got too dark with the grad filter adjustments.Turn on the show mask option so you can see exactly where you need to work.( A hint)... As you work with the brush, you can even set a moderate color hue to see where your painting (adjusting), and then select that adjustment marker and go back to the color option, and put the saturation and color back to white, which will restore your original view .

Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: albedo13 on November 12, 2012, 12:28:30 PM
My apologies to everybody contributing here, I have not checked this post for a while.  I really appreciate the suggestions and techniques, I can't wait to go back and try out some of these.  I have been aware of, but never considered using the Graduated Filter in ACR just because of there being so many irregularities in the shape of the background etc.  I am reading Jeff Schewe's Digital Negative book and am seeing that he uses it quite often in the same situation, so with the suggestions here I will definitely give it a try and see what I can come up with.  The next challenge after this one is enhancing the vapor cone that forms at high speed/high humidity so that it is more visible against a totally overcast background sky...


Title: Re: ACR Adjustment Brush versus PS Masks & Refine Edge for Backlighting
Post by: rambler44 on November 13, 2012, 08:46:49 AM
You guys are way ahead of me in your PS skills, and you can maybe tell that I have been using Photoshop Magazine for 'tips and tricks'.

The May/ June 2012 edition includes a lengthy "Special Section" on CS6 including ACR 7 and the Adjustment Brush!