PTLens and CS5 – Remove Keystone Distortion and Replace Missing Details

I’ve blogged about PTLens in the past. Some probably think that the addition of lens distortion correction to Photoshop CS5 has eliminated the value of PTLens. Well, in my opinion far from it. PTLens provides distortion correction for many small sensor cameras that CS5 can never afford to concern itself with. And PTLens has very easily mastered controls for perspective correction, specifically the elimination of keystoning in your image.

As the first stage in processing, you should remove all distortions and crop to the look you want. That way, you do not waste any energy or computer power on processing parts of the image that you will ultimately remove. Some of these extra elements can be distracting and lead to a less than optimal result by confusing the eye.

This article is the first stage in the HDR processing of an image in my article on Topaz Adjust 4.

PTLens is sold through ePaperPress on this page. It is inexpensive and runs stand-alone or as an external editor for Lightroom or a plugin in Photoshop. It supports 8 and 16 bit color, and it support 32 and 64 bit versions of CS4 and CS5. 32 bit only in earlier versions of Photoshop. I also runs in Elements. And on the MAC in Lightroom (I think.)

The controls at the bottom-middle are the meat of the tool. It will read the EXIF info and do its best to guess which lens or camera you have, and it is usually right on. You can switch the distortion correction on and off at will, which is useful if you want to run the tool more than once. You can only correct lens distortion once, after that you are introducing the reverse distorions, and good luck trying to correct *that* :-)

By the way, for any lens or camera that is unknown, you *must* disable barrel-pincushion correction, else the OK button is never enabled. Also, the Scale button is *only* enabled if you touch one of the other correction buttons. So if all you want to do is to correct barrel distorion and scale the image, well, no can do. I hope Thomas fixes that one day. If *any* changes are made, the scale button should be enabled. In fact, why not enable it no matter what? His resizing algorithms seem rather good.

On the right, you have three tabs. My goal with this article is to demonstrate the middle tab, Perspective correction. I can say that the vignette correction is very useful. I often use this one in preference over Photoshop. It again has sliders that seem to have a good level of control without feeling twitchy. I have to say that I rarely use his Chromatic Aberration correction though, as I quite like the corrections in ACR5 and ACR6. I also like my Shay Stephens fringe removal action. But I’m sure it does the job.

Back to the work flow.

You can see that PTLens has correctly guessed the camera and lens used for this image. And it has removed the pincushion distortion inherent in most consumer zoom lenses.

 

In this image of just the image panel in the dialog, I have turned on the grid, which makes a huge difference when scanning for perspective issues. I can see from this that the buiding is leaning outwards, a case of reverse keytoning caused by shooting the building from above at a downward angle. I need to dial the sliders a bit to push the top of the building together and that often also requires a bit of rotation. You find that these two sliders interact the most often when working with perspective.

The final result required +12 of vertical distortion correction and –0.2 of rotation. A very small amount, but it is amazing what the eye sees, especially when the lines are near the border, as is our horizon. The final result from PTLens looks like this.

Obviously, I did not use the built in scaling capability. That’s because I want finer control of this crop. I was to try to save the gentleman looking over the lady’s shoulder, which I did not do the first time I processed this image in Topaz Adjust. This time, though, I have the CS5 content-aware fill to help me out. So first I crop:

The crop tool works very well for this task, and does not change the pixels or resolution unless you tell it to. I always leave those moxes empty and only fill in the dimensions, which is really just the proportions or more accurately the aspect ratio of the crop. And you can see that I will be forced to recreate the upper left corner, which was removed by the original pincushion distortion fix.

To fill in the area, select with the lasso tool and hit delete. This brings up the fill dialog to select the content you want to replace the deleted area with. CS5 adds the new “content-aware” fill, which is wicked powerful. It does wondrous things at times.

I can’t really call this a wondrous job, but it has certainly left me with little to do. Just paint in the top of the bubble and paint out the reflection above their heads and all will be well.

That’s pretty good. And of course, when reduced to normal viewing sizes, the repair is invisible. For advanced photographers or enthusiasts, I highly recommend the Photoshop tools. There is a ton of info on these and the advanced nature of the tools and filters makes short work of certain difficult tasks.

Now you can go back to the Topaz Adjust 4 article to continue with this image.

Topaz Adjust 4 – A Taste of HDR on a Budget

I’ve been using Topaz Adjust almost since it came out. I bought Adjust and DeNoise for a fairly low price during an introductory offer a few years ago. They have been offering free upgrades ever since, and the tools have definitely gotten more refined. Adjust has a far superior interface in version 4 than it did in earlier versions, although this current interface is similar to that introduced in version 3. This interface has a fairly quick preview mode and a few extra default looks over version 3.

Why do I say default looks? Well, Topaz Adjust is driven by a bunch of sliders that control all aspects of exposure and detail. These two interact a great deal, providing a near infinite variety of looks along the way. Topaz Adjust offers a whole array of default settings that you can use as they are, or use as a starting point for further tweaking.

I had used Topaz Adjust 3 to tweak up an image of the parliament buildings in London that I shot from the eye, just as it was descending back to earth. The image is rather flat, as it was a very dull day.

I definitely like the composition, though, as it shows the bubble next to us and some people doing exactly what I am doing, shooting the pairliament and Big Ben from above. But the dull colors and low contrast make it a boring image.

Using just ACR6 and CS5, the saturation and contrast can be adjusted.

It doesn’t look too bad, but somehow the image still looks a bit dull. More of an HDR look is needed I think.

So it’s time for Topaz Adjust 4. Now, before getting to Topaz itself, I need to remove the keystoning and crop the image to remove some of the bright section at the very top. It is distracting and adds nothing to the image. I use PTLens for removal of distortions of all kinds, and you can read about that in this separate article.

So once the image has been prepared for color and tone adjustments, it is time to open the topaz adjust filter. It comes up in a fairly large modal dialog, shown here:

There are several panels for you to use during your editing session. Click through to see the larger screen shot (hint: right click, open in new window so you can read while referring to the larger panel in a separate browser window.) Starting top left and proceeding clockwise:

1. Preview panel. When you float your mouse over any of the default effects in the left hand panel, the preview panel top left shows the effect while the mouse hovers.
2. Tabs for original image and adjusted image. You can also see the original image by clicking on the main diagram in the middle and holding the left mouse button down.
3. Top right os the original view of the image.
4. Top middle has a few useful buttons to change the size of the main image preview in the middle. You can see the original image fit to view. You can see a 1:1 view, which allows you to see all the noise for fine adjustment of sharpening or noise reduction. And you can increase or decrease magnification in small increments. There are also a couple of buttons for undo and redo. Handy stuff.
5. The right hand panel contains the real meat of the dialog, many sliders that affect everything about the image. These are covered in much more detail in a moment.
6. A strip of buttons at the bottom provides managing of presets that you or others create, a menu showing tutorial links etc, the cancel and ok button for the whole dialog, and a reset all button to go back to the preset value itself. There is also an “I Feel Lucky!” button to presumably let Topaz pick a preset for you. I never get lucky with that button.
7. And finally the left hand panel containing the list of presets. Lots of interesting choices based on exposure, detail, color, or many combinations thereof. There are several new ones in Topaz 4 – a couple of new HDR looks (note, Topaz Adjust already had several), a couple of night time looks, and some new sketching looks. Pencil sketches etc. This tool is incredibly versatile.

So on with the work flow.

You first choose your preset. In this case, exposure color stretch looks pretty good.

Then you go over to the right hand panel and start tweaking the sliders. The first bank is the exposure bank.

Adaptive Exposure and Regions work hand in hand here. These are responsible for a lot of the HDR look you can get. Here is the tool tip you get:

 

You can think of Adaptive exposure as “Shadows and HIghlights” on steroids. Then, you have regions:

Think of this as “radius.” Basically, you get very fine details as you dial it up, and much coarser details as you dial it down. Kind of like sharpening versus local contrast adjustments. The unsharp mask tool can do both, and the radius is what makes the difference. Same thing here. But on steroids again.

Contrast, brightness, highlight and shadow are obvious here. And yes, highlight and shadow are pretty much what you get in photoshop. The Adaptive Exposure is similar conceptually, but adds the HDR twist.

The next panel is the Details panel.

 

Strength is quite similar to “amount” in most sharpening tools. They call it the “degree of detail enhancement.”

Boost is “the degree of small details enhancement.” This is a convenient slider with a small radius. Between these two, you have a lot of different looks possible. Note, though, that setting boost to zero essentially cripples the Strength slider. There is a definite interaction there.

Threshold is supposed to control the number of elements that are considered as details. And it seems to do that. Setting Threshold to the minimum value cripples the radius slider. Threshold has an effect not unlike radius. The two together offer a incredible amount of control over contrast and detail.

Sharpen removes image blur. This is a pretty standard sort of sharpening tool, but since the rest of the sliders all affect the perception of sharpness in one way or another, you really need to play with them all and watch them react to each other before getting a feel for the effects you like. I doubt that there are many tools that offer the kind of detail enhancement you can get with this one.

The final two panels are Color and Noise.

Adaptive saturation is similar to the other adaptive controls in that the job is to even out the image. This helps give the HDR “look” to an image. Regions is related in that it controls how finely grained the image looks to adaptive algorithm. I.e. how many parts into which the image is divided. Choosing a larger number provides a more even result.

Saturation and saturation boost provide an increase in overall saturation, and an increase in saturation of less saturated areas, respectively. And Hue provides a minor hue correction control. Very much unlike the Hue/Saturation slider in Photoshop, which swings the hue wildly between extremes. This one is very limited, which is also very helpful.

The version I did of this image way back a few years with Topaz Adjust 3 is still one of the best ones I’ve done.

For this article, I ran it again in Topaz Adjust 4 without referring to the above image and I came up with a very similar image. I should have cranked up the regions slide for saturation I think, but otherwise I obviously used mostly the same settings.

A little brighter than the previous one. I think I like that. More golden. And, of course, I handled the other bubble better, preserving the gentleman that is looking of the lady’s shoulder as she shoots the buildings.

As I mentioned, though, there are many looks available with Topaz Adjust 4. Here are three others, all new.

Sketch – Dark Charcoal

Dark – Ghostly

HDR – Sketch

 

Remember that you can run Topaz Adjust 4 on a separate layer and use all of its powerful tricks to pull out colors or detail or anything else you can think of. Then you can use a mask to paint on only the areas you want to keep … for example, I’ve run Topaz just to pull out feather detail on a bird and left the rest of the image alone. This really emphasizes the details in that one areas. Ditto with moon shots. There is no end of fun with this tool.

A few more examples of pseudo-HDR from my gallery:

  

In my opinion, It’s a worthy addition to almost anyone’s toolkit. 

F70EXR – Larger versus Medium Size – Yet Another Test

The EXR sensors have afforded us a new way of shooting. Hardware assisted dynamic range (DR) extension provides far better captures in the day time than can be obtained by lesser sensors. This because they can split the sensor into two separate sensors and stop the exposure early for the highlights. The combined image can store a much wider dynamic range than any other small sensor.

This binning mode (combination of two adjacent like-colored pixels in the case of the EXR technology) also has the advantage of reducing noise as ISO rises.

But the EXR technology can be ignored in a high resolution mode that uses all of the pixels as individual picture elements. I have railed against this use of the cameras on any EXR model because I have looked at images produced in both modes from all of the EXR sensors (F200EXR’s larger sensor, shared with the S200EXR, F70EXR’s smaller sensor, and F80EXR’s smaller and denser sensor) and none of them retain more low contrast details in hi res mode. In very bright light, they can retain slightly more detail with very bright details, but edge integrity still suffers as the noise reduction that must be used on hi res images kicks in.

I’ve shown this several times and you can search this blog for the articles if you would like to see the tests.

But … a fellow named Oasis Feng left a comment on my how to shoot article for EXR sensors that he had discovered that the 10mp L size mode for the F70EXR is not completely useless. He shot a long exposure with a tripod in a dark environment and he sees more fine details with the large image.

This, of course, forces me to test that specific example, since none of my L vs M tests have done exactly that.

The short answer is that M upsized to L size still defeats the native L size. It’s quite subtle, in that the L size shot at 100 iso (when using tripod, there is little need to raise ISO unless 8 seconds is insufficient for your exposure) retains slightly better noise character. This because I double the size of the noise particle on upsizing the M image. But the advantage there is pretty small.

I shot a tooth brush in a dark bathroom at 8 seconds, and that resulted in a slight underexposure that required lifting in photoshop. I cropped the two out of camera images (after upsizing the M image to match) and put them together before performing any other processing. I lifted the exposure, added a bit of contrast, and sharpened the crops together.

The arrows in the following image show where I prefer one over the other for detail retention. The L image does have a couple of better spots. But the M image has more.

It’s quite close, so don’t get too excited about it. It is obviously not going to make much difference at web sizes, but as with any small sensor, low contrast details such as those in shadow, are lost earliest. If you shoot in M mode, you will always hold them longer. There is no way around that. Lower density wins.

Click through to see the full sized crops.

Scotty said it best: “Ye canna change the laws of physics!”

F70EXR - Another Dark and Rainy Night

I met Karen at her office before heading downtown for a comedy show the other night. Great show by the way. Absolute Comedy, if you’re ever in Ottawa.

Her office is in a bit of a hippie neighborhood, which makes for some interesting people and some very interesting buildings. The small parking area next to her building has a wall on its other side on which someone went to town with the paint. A very nice mural, although I admit that I cannot see the significance of the three sections.

But here they are in a row. Shot with the F70EXR hand held. Processed with a little help from the new ACR6, CS5 and Topaz 4, all of which will eventually be mini-reviewed on this blog.

Of course, when we got back to the parking lot the wall was no longer visible in this way.

I got home later and looked up to see a plane flying towards me. It was to fly right over my house on its landing path. We get that when the wind is just right. So I thought I would try my panning overhead. Not so good :-)

If I stretch the exposure like crazy, you can sort of see impressions of the wings … but the image looks like crap.

It started to rain at that point and I turned my attention to the beautiful yellow tulips that insist on growing in my garden every year, despite a total lack of attention to their health. I tried many shots with flash (there is no hope whatsoever of getting a decent shot hand held with a compact at night) and out of at least 15 images, this is the one I thought was ok. Not great, but ok.

The issue, of course, is the use of direct flash. DIrect flash never looks all that good (exception, appropriately used ring flash), but it is all you have with a compact unless you set up some off board SB26 flashes on slave + delay mode. But that’s way too much work for this kind of shooting and it was raining :-)

To handle the direct flash, all you can do is work with the contrast and brightness until you minimize its effect. As I did here.

Carrying your compact everywhere affords a lot of opportunity for interesting shots. I keep the cam on the settings I recommend – P mode, auto ISO 1600, DR400, M4:3 (or M3:2) and I was able to get these shots with no real thought to the exposures. I set my cam for magnify mode when it displays the image that is shot, so I can clearly see if I am getting focus and if I am blowing highlights.

For the former, I actually had to put the AF assist lamp on, which made a huge difference. For the latter, you play with compensation. I ended up at –1EV to hold the highlights. Never be afraid to underexpose to hold highlights. These cams have a lot of latitude (decent quality of pixels) so you can raise the exposure without getting undue noise.

My new account was banned! LOL *updated again :-)*

Interesting that the use of “temporarily” was quite incorrect. They wiped that account off the face of the earth.


I had responded to a truly obnoxious post insulting half the forum made by Greg Photo Sydney. And I'm thinking that this joke in my initial reply might have tipped the scales to the ban:

Q: How do we know when Greg Photo Sydney is insulting someone?
A: He’s typing.

(Update: GPS was permanently banned later on for persistent extremely bad behavior. I feel vindicated :-)

Note, this ban is DPReview-wide … that account cannot log in.


*Update: Duh … I had forgotten to check that email account (kdletkeman) and of course the notification of the permanent ban was sitting right there :-)



Update: Obviously it is bad form to create an account to get around a permanent ban, although people do it all the time. But in this case I felt justified as my ban was not.

So, to recount the history here:

• I took a 3 month break, largely because I was tired of seeing the same stupid comments from the same *experienced* posters and then getting into the same arguments
  
• I came back to test the waters
  
• I responded to a particularly obnoxious post by GPS
  
• Dave the weasel ostentatiously announced that he had pressed the complaint button (no reason given)
  
• One presumes that his cronies did the same
  
• I was permanently banned only from the FTF with no explanation at all. None.
  
• After a few days, I created a second account.
  
• History repeated itself
  
• I was told by DPReview in an email that I must resolve the first ban through the feedback mechanism.
  

So … what will I gain if I speak with the moderators? Well, they will repeat what they told me last year when they permanently banned me unjustly and then reversed it after checking out the facts.



That came directly from one of their moderators in a statement telling me that they were reversing a lifetime ban.

Basically, they are saying here that some people press the complaint button a lot and that makes too much work for them so I need to stop being a lightning rod. They suggested in a later email that I should put them in my ignore list.



What that says is that I am allowed to post so long as I put D, G, P and a few others on my ignore list and never respond to them. That way, they have no reason to push the button (although they have proven they do it anyway.)

Obviously, I did not do that and I was banned within 48 hours of returning after my sabbatical. That tells you how easily the undue use of the complaint button can be used these days to change the face of the forums.

**Update**
Read this obnoxious and rather neurotic response from Dave to Velvet Anty, and of course to this article. You will laugh your ass off if you try to hear it in a hysterical, shrieking voice … 

A few points of explanation from points in Dave’s diatribe:

1. Dave did have a comment removed from this blog under threat of legal action. (Update: When he annoys me, I think of him as "threatens-a-lawsuit.") The comment was not defamatory, and certainly not actionable in my opinion. But I removed it as a favor to the fellow who left it. He said he didn’t need that shit in his life, and who can argue? And by the way Dave … it is *not* illegal to write the truth. One need only look at your gallery and one would have no issue with the wording of the comment that was removed. To repeat … it did not defame …. it simply commented on an observable fact based on *dozens* of images on your own gallery. An observed fact that is trivially verifiable is *not* actionable.
   
2. If there was a part of the removed comment that slammed some new FTF poster, it had nothing to do with them not posting any more. That kind of thinking is moronic. How would that person even see a comment buried inside a blog that Dave says is not even read by the majority on FTF :-)
   
3. Dave is quite correct that my accounts are both banned from the FTF at this time. Dave even alludes to some other account that he alleges is also banned, although one wonders how he would know that. Interesting that Dave is essentially admitting to hammering on anyone who even writes like me.
   
4. Dave comments “In reality, that blog contains some of the most slanderous, and libelous, comments about individuals, which I have ever read.” This is, of course, utter bull shit. I would never write something that I thought could be actionable. And by the way Dave, slander is defamation by oral utterance. Not the sharpest tool in the shed I’m thinking.
   
5. An interesting and truly disingenuous comment Dave made is “Crikey ! I have not responded to them for months. Again, fully documented. I don't care if they are here, or not.” He somehow thinks using “them” distances him from his own comments. Silly boy. Anyway, he had not responded to me for months because I was abesnt from the forum for *3* months. And if he did not care if I was on DPReview, he would not be able to name every ban and some that have not even happened. He would not be intimately familiar with the content of this blog and with the comments on that content. He would not be accusing random people of being me. He’s simply obsessed. Nice to have fans though :-)

Dave’s diatribe indicates that he has extremely intimate knowledge of this blog and its content. And the comments about its content. I wonder how he came by that … :-)

F80EXR – A Cold and Rainy Night

Time for another test of the F80EXR white balance. I beat it up pretty bad because it does not play nice with the blue channel when the light must be heavily pushed. I really dislike that property, because the F70EXR did not do that. But … fair is fair … the camera should be given a chance to prove itself at night outside in the dark. In fact, by only incandescent light. We tend to be forced to shoot by that light when we are out at night after all …

So the first thing I did was to set custom white balance on a rail near my house. This rail is not perfectly white, so the CWB came out a little more blue than it should … but I like a rough and tumble test. Let’s see how it did.

My method was to shoot a few images in the CWB I had set, and then reshoot them in AWB. But I will write as if I shot in pairs, because that will flow better :-)

First thing, I shot the front porch. This is the light that was used to set AWB in the first place, so similarly colored items should come out white. The window frame for example.

The two originals in CWB and then AWB:

And here are some crops to reinforce the obvious :-)

 

*BIG DIFFERENCE*

It’s pretty obvious that this kind of image, with a dollop of shadow wunning along the bottom right and on and under the mailbox, will over stimulate the blur channel. There is some very obvious blur blotching in the top image. The bottom image, on the other hand, is rather warm, but is also fairly free of noise. I could live with that image quite well.

On the other hand, I do prefer the colors in the first image, at least the colors not involved in the chroma noise situation. So is the image irredeemable? Well, by happenstance I received the release announcement for Topaz DeNoise 4 tonight, so I downloaded and installed the free upgrade to see what it could do. And I was pleasantly surprised. Although it has really been refined to handle up to four stops of more fine grained noise, it handles this level of noise with aplomb as well.

The denoised versions:

Now the CWB image is quite acceptable and the AWB image is really clean. Very nice plugin this one.

Conclusion: CWB is risky under incandescent light … might be better off with AWB.

Next pair … the neighbors’ yards across the street. Beautiful shiny pavement from the rain.

Both images look ok to me. The former is a better color for my eyes … but bear in mind that I am color deficient. And did you click through and catch the netting visible under the hoop on the right? Amazing for 1600 ISO!

Conclusion here would be that CWB is not fatal and may enhance the colors for some people. Those who prefer the cool look at night.

At this point, I turned my attention to capturing the plants near my porch. This was rather problematic since there was very little light near the ground. I was forced to turn on the AF ailluminator (I never use it normally) and after trying a few images, I had to switch on the flash to get anything at all. And the end result was rather good.

The bleeding hearts near my door … I think this is the same sprig that appears in the last post. The only reason why I got an interesting background here is that I allowed the camera to choose 800 ISO.

And a tulip that lives under my porch like a troll … unlike the bleeding heart, this one was not under the overhand and I got some nice droplets on it.

Note, I made a mistale and left a small light colored twig just inside the frame on the right. You should always clean up the frame … remove distracting elements as they serve no purpose.

So I think the F80EXR did a decent job. If you stay away from custom white balance under really warm light, it makes fine images.