Apple has updated the long-ignored iPhone SE model.
The new version is very similar to the outgoing iPhone 8 and maintains the same glass-back design, single rear camera and water resistance. Frustrated that you can't get in the studio with a model to test and experiment with lighting set-ups and shooting ideas? This set. The Fujifilm X-T is a low-priced mirrorless camera with a stunning 3. Dive into our review to see how it ranks against its peers. Find out why it may be the reason he's on the DPReview team today. The latest legal ruling follows a similar case from about a tweet that featured a copyrighted image of Tom Brady.
The lens doesn't currently have a price, but you can count on it being one of the—if not the—most affordable 50mm lens for Sony's aseries cameras. The 33mm F1. Recently we caught up with Fujifilm's Toshi Iida to talk about the X-T4, XV and, of course, the ongoing impact of the coronavirus epidemic on Fujifilm and the camera industry as a whole.
Fujifilm's newly-formulated Acros II will be hitting store shelves soon! Curious what it looks like? Check out our sample gallery, chock full of 35mm and format scans. We asked two executives of Japanese imaging companies whether or not this incentive could help their operations.
The new model supports nearly all 35mm analog SLR cameras and can be used with dedicated back covers designed for the most popular camera models. Year-over-year, sales of mirrorless interchangeable-lens cameras decreased by Like so many, self-employed photographer Suzi Pratt found herself at home with lots of time to kill. Here are the steps she recommends for those in the same position, both to fill time during isolation and to prepare for what's next.
The two-minute video shares a behind-the-scenes look at how commercial film production company Threefold made an old ambulance the ultimate all-in-one film truck. Compact and affordable, the new Sirui 50mm anamorphic lens comes in options for three camera mounts — so we tried it on each of them. See the lens in more detail and read about the benefits of using it on each system. The Fujifilm XV is a camera designed to tag along on adventures large and small. We brought it along on plenty of excursions during the course of testing — back when we were able to do that sort of thing — from trips to the coast to walks around the block.
We shot Fujifilm's new Acros II black and white film in both 35mm and medium format, developing it ourselves. We also compared it to Fujifilm's Acros film simulation.The Lensfun library provides many different mathematical models for lens distortion. They are mostly of theoretical interest but could be useful when porting calibration data made with some other software.
These models are described in the comments to the lfDistortionModel type. For our needs we'll use just two models: the "ptlens" model, which is a fourth-order polynomial:. Thus, poly3 is suitable for lenses with more predictable distortions, and ptlens model can be used if the poly3 model does not give good enough results which means that your lens distortion can not be approximated with a simplified 3rd-order polynomial.
As Pentax 12—24 is a very linear lens with very little distortion for its wide anglewe'll use the poly3 model here. Computing the ptlens model coefficients is almost as simple, you'll just have to click more checkboxes in Hugin :. So we now will run Hugin and load several images we made at one focal length three to be precise at a distance of at least 8 metres. Try to place points in high-contrast places like corners and edges. Try to pick points spreaded around the whole image, and don't forget to put points in at least two corners of the shot.
Here's a example of how a good distribution of control points looks:. You also can try to use the autogenerated control points generate them with autopano-complete.
If everything goes normal, Hugin will compute new values for all marked parameters. If something goes wrong, Hugin will display a message that the values computed seem way out of their normal range. This usually means that the control points are wrong somewhere; check them once again. If nothing helps, try to make a new series of test shots. Repeat these steps for every focal length at which you made test shots. This will take quite a bit of time, but in the end you will end with something like this:.Remember Me?
Forgot Password. The Latest. Pentax Stores Pentax Retailer Map. Go to Page Accessory Search. Style Selector. All times are GMT The time now is AM. See also: NikonForums. It's great to see you back on the forum! Have you considered joining the community? Forum Search Options. Advanced Search. Pentax Items for Sale. Wanted Pentax Items. Price Watch Forum. List a New Item. Get seller access! Pentax Retailer Map.
Sample Photo Search. Recent Photo Mosaic. Today's Photos.Lens corrections help offset imperfections present in nearly every camera image. These might include darkening near the corners of the frame, otherwise straight lines appearing curved, or color fringes near edge detail. Even though these often aren't obvious in the original photo, the benefits of their removal almost always are. However, lens corrections also have the potential to make images worse if not carefully performed, and depending on the subject, some imperfections can actually be beneficial.
Results after vignetting, distortion and chromatic aberration correction. However, lens correction software is typically only able to fix certain types of each imperfection above, so being able to identify them is key. The following sections describe the types and causes of each imperfection, when correction is possible, and how to minimize imperfections in the first place. This describes the gradual fall-off of light towards the corners of your image, and is perhaps the most straightforward lens imperfection to observe and correct.
Note how internal vignetting is most objectionable only at the top left and bottom right due to the subject matter, even though the effect applies uniformly to all four corners. The first can be minimized by stopping down your lens using a higher f-numberbut the second is independent of lens setting.
Natural vignetting is therefore unavoidable, unless one is able to use a lens with a narrower angle of view, or a specially-designed corrective filter that discards light toward the image's center uncommon except perhaps with large format cameras.
Vignetting can often be fixed using a single "amount" slider, although you can sometimes also adjust the center of the vignetting correction using a "midpoint" slider but this is rarely needed.
However, correction will increase image noise toward the corners, because digitally brightening an image amplifies both the signal and the noise equally.
Artificial Vignetting. Some photographers actually add vignetting to their images in order to draw attention to a central subject, and to make the frame's edges appear less abrupt. However, you'll want to do this by applying the vignetting after any image cropping sometimes called "post crop vignetting". This can give otherwise straight lines the appearance of bending inward or outward, and can influence the depiction of depth:.
Blue dot represents direction of camera; red lines mark converging parallel lines. With landscapes, distortion of the horizon and trees are usually most detectable. Placing the horizon along the center of a photo can help minimize the appearance of all three types of distortion. We see it with our own eyes, but our mind knows the correct 3D positioning of objects and therefore doesn't perceive these lines as converging.
Fortunately, each of the above types of distortion is correctable.
HKO AT A GLANCE
However, this should only be performed when necessary, such as with subjects that include straight lines or are highly geometric. Architectural photography is often most sensitive, for example, whereas many landscapes aren't noticeably affected.
However, make sure to use the grid overlay feature if available so that you can more easily assess whether editing has made lines straight and parallel. Distortion correction usually requires cropping out curved edges of the corrected frame, which can influence composition.
Correction also redistributes an image's resolution; with pincushion removal, the edges will appear slightly sharper at the expense of the centerwhereas with barrel removal the center will instead appear slightly sharper at the expense of the edges. With wide angle lenses, barrel distortion is actually a helpful way of offsetting the corner softening that is common with these lenses, for example. Chromatic aberration CA appears as unsightly color fringes near high contrast edges.PTLens 8.Using PTLens to correct Lens Distortion
Download free. If EXIF damaged, incomplete, or missing may manually specify the brand camera and lens of course, if he replaceable. By itself "knows" a great many models of cameras and interchangeable lenses. The PTLens es 8. PTLens is available as a standalone application or Photoshop plug-in.
The plug-in version works with Photoshop version 6 and above and all versions of Photoshop Elements. Available History in PTLens kr 8. It all started August 20,when in a newsgroup with the following message: "I need the program with batch processing that reads the 'EXIF information of 'JPEG file, finds the next match in the table, and automatically corrects distortions. Several years of work and 30, lines of source code of a simple DOS program to run from the command line later became PTLens application and Photoshop plugin that corrects the distortion, vignetting, chromatic aberration, and perspective.
To date PTLens - the first and the best program for the correction of distortions geometric distortion introduced by imperfect optics of camera lenses, it is possible to control the white balance. If 'EXIF damaged or missing is not complete, it is possible to manually specify the brand of camera and lens if removable. PTLens User 8. It will be extremely useful for both novice photo enthusiasts and professional photographers. Post a Comment. All Cracks Software Site.
PTLens is the first application to automate the correction of distortion. It all started August 20,when in a newsgroup with the following message:.
Release: Language: Multilingual. Solution : Key License. Size: 3. Email This BlogThis! Newer Post Older Post Home. Social Profiles.PTLens was recommended to me by a fellow photographer and proves to be one of the easiest ways of fixing four common problems:. It comes in Mac and Windows versions; on the Mac it runs in native bit mode if invoked from Lightroom and is a Universal application, meaning no need for the buggy Rosetta application which causes spontaneous reboots in Snow Leopard and supports full bit color TIFF and PSD file formats.
Perspective correction has been done in Photoshop CS2. As for chromatic aberration and vignetting, Lightroom version 2. Many common lenses are programmed in though not, for some reason, fisheyes.
There is no practical difference, defishing rendering the field of view of a 12mm hyper-wide rectilinear lens. PTLens saves the processed file back into the image stack in Lightroom and is very fast, the preview reacting in real time as the sliders are worked. When it comes to correcting more regular lens distortions, PTLens is in its element, as it has a large database of lenses with all the settings stored for you, whereas Photoshop has none — you have to do everything manually.
Barrel time — mm Canon lens at 24mm. Here are the before and after images, the latter processed in PTLens using the programmed settings from PTLens with no other adjustments:. Take a good look at the handicapped parking sign before and after correction. Highly recommended. PTLens has finally consigned Photoshop to the trash, where I have long wanted to place it.
Remove Barrel Fisheye Effect For Perfect Aerial Photos
As an architectural photog, it has been a personal fantasy of mine to NOT have to export into PSP just to make minor perspective tweaks. I imagine that LR will eventually have this feature built in someday, but until then you have shown me the light. Thanks for this post and hats off to a great blog! The easy way to fix distortions. Correcting chromatic aberration color fringing and vignetting — not tested here It comes in Mac and Windows versions; on the Mac it runs in native bit mode if invoked from Lightroom and is a Universal application, meaning no need for the buggy Rosetta application which causes spontaneous reboots in Snow Leopard and supports full bit color TIFF and PSD file formats.
Here are the before and after images, the latter processed in PTLens using the programmed settings from PTLens with no other adjustments: Take a good look at the handicapped parking sign before and after correction.In geometric opticsdistortion is a deviation from rectilinear projection ; a projection in which straight lines in a scene remain straight in an image.
It is a form of optical aberration. Although distortion can be irregular or follow many patterns, the most commonly encountered distortions are radially symmetric, or approximately so, arising from the symmetry of a photographic lens.
These radial distortions can usually be classified as either barrel distortions or pincushion distortions. See van Walree.
In barrel distortion, image magnification decreases with distance from the optical axis. The apparent effect is that of an image which has been mapped around a sphere or barrel. Fisheye lenseswhich take hemispherical views, utilize this type of distortion as a way to map an infinitely wide object plane into a finite image area.
In a zoom lensbarrel distortion appears in the middle of the lens's focal length range and is worst at the wide-angle end of the range. In pincushion distortion, image magnification increases with the distance from the optical axis. The visible effect is that lines that do not go through the centre of the image are bowed inwards, towards the centre of the image, like a pincushion.
A mixture of both types, sometimes referred to as mustache distortion moustache distortion or complex distortionis less common but not rare. It starts out as barrel distortion close to the image center and gradually turns into pincushion distortion towards the image periphery, making horizontal lines in the top half of the frame look like a handlebar mustache.
Mathematically, barrel and pincushion distortion are quadraticmeaning they increase as the square of distance from the center. In mustache distortion the quartic degree 4 term is significant: in the center, the degree 2 barrel distortion is dominant, while at the edge the degree 4 distortion in the pincushion direction dominates.
Other distortions are in principle possible — pincushion in center and barrel at the edge, or higher order distortions degree 6, degree 8 — but do not generally occur in practical lenses, and higher order distortions are small relative to the main barrel and pincushion effects.
Barrel distortion may be found in wide-angle lenses, and is often seen at the wide-angle end of zoom lenses, while pincushion distortion is often seen in older or low-end telephoto lenses. A certain amount of pincushion distortion is often found with visual optical instruments, e. In order to understand these distortions, it should be remembered that these are radial defects; the optical systems in question have rotational symmetry omitting non-radial defectsso the didactically correct test image would be a set of concentric circles having even separation—like a shooter's target.
It will then be observed that these common distortions actually imply a nonlinear radius mapping from the object to the image: What is seemingly pincushion distortion, is actually simply an exaggerated radius mapping for large radii in comparison with small radii. A graph showing radius transformations from object to image will be steeper in the upper rightmost end.
Conversely, barrel distortion is actually a diminished radius mapping for large radii in comparison with small radii. A graph showing radius transformations from object to image will be less steep in the upper rightmost end. Radial distortion that depends on wavelength is called " lateral chromatic aberration " — "lateral" because radial, "chromatic" because dependent on color wavelength.
This can cause colored fringes in high-contrast areas in the outer parts of the image. This should not be confused with axial longitudinal chromatic aberration, which causes aberrations throughout the field, particularly purple fringing.
In barrel distortion, straight lines bulge outwards at the center, as in a barrel. In pincushion distortion, corners of squares form elongated points, as in a cushion. In mustache distortion, horizontal lines bulge up in the center, then bend the other way as they approach the edge of the frame if in the top of the frameas in curly handlebar mustaches.
Radial distortion, whilst primarily dominated by low order radial components,  can be corrected using Brown's distortion model,  also known as the Brown—Conrady model based on earlier work by Conrady. The latter is also known as decentering distortion. See Zhang  for additional discussion of radial distortion.