When people used early ultrawide angle lenses that had visible distortion, did they simply accept the fact and print it too ... or were there mitigations for things like critical architecture photography? Were contraptions like non-planar paper/film holders, and/or specialized optics in the enlarger light path, used?
122217
Were there ever any tools to correct for lens distortion in the film-only era? I'm thinking a device that contained a lens system that you could alter, or a soft workable lens that you could fine tune, to transform the distorted image back again. Or maybe even something as easy as not resting the photo paper on a flat surface during development.  I haven't heard of anything like this but I'm sure that it was something photographers in certain situations wanted to do.
81317
Someone mentioned that "veiling glare" or "veiling flare" was to blame for reduced contrast in a photo. What does this mean exactly?  What causes veiling glare, and how can it be avoided? How does it relate to those floating polygonal lens flares one often sees in movies?
72588
We have a question and answers outlining the . I'm interested in the other DSLR makers, and how the cameras they make compare in terms of significant features, system design philosophy, and unique or interesting photographic capabilities enabled or made easier by these cameras. Likewise, what such things are not handled as well?  Take "the big two have more market share" and the associated advantages of availability, accessibility, and third-party support and documentation .  I'm not interested here in compact cameras, interchangeable-lens cameras with electronic viewfinders, or in rangefinders. (If you're interested in that, though, see )  P.S.: Differences in lens lineups are covered at
109069
I use Adobe Lightroom to remove the barrel distortion from GoPro images. Does anyone know if this software uses the Brown-Conrady model to achieve the lens correction? If not which model does it use? From an extensive Google search I have done, I didn't come up with an answer.
100059
Ever since I've heard of extension tubes I've been curious if they somehow crop the image that appears on the camera sensor.  Based on , the answer is "no" (at least not that I can tell).  Now that I know that, why not?  It seems like they would somehow muck up the image that appears on the sensor, and while they obviously do alter the DOF, it looks like the image still appears on the entire sensor. Obviously my understanding of how the lens forms an image on the sensor has something wrong with it, but what is the actual effect on the light when using an extension tube?
94507
When on the road as a tourist, I often do not carry a reflector of flash. Now I am at a location with very strong sunlight and I want to take a photo of a companion in front of a nice scenery or building, the classic "we have been here" photo.  With very strong sunlight however, specially at a slight angle, I either get it into the person's eyes and they squint like crazy, or they are in the shade and their whole face is black.  Please note that I do not have aspirations to take a professional photo in such circumstances, but at least something acceptable.  Is there an easy trick to deal with that?
45084
There was recently a video posted about how different focal lengths affect portrait photography, specifically how distortion at smaller focal lengths have more distortion and are less flattering.   So the question is that, because we always talk about how Canon's cropped sensors have a 1.6x crop factor so the lenses are essentially longer, does the distortion caused by the lens change when used on a cropped sensor?  My initial thought is "no" given that my idea of how a cropped sensor works is like printing off a 8x10 picture and then cutting out the 4x6 that I like: the picture doesn't change, only my view of it.   However, if distortion is least prominent at the center of the photo and most prominent at the edges, then the perception of the net effect of the distortion would be changed by using a cropped sensor and I get confused again.   Any thoughts?
120247
I have a set of concave/convex mirrors/lenses, and I have drawn out all of the ray tracing diagrams for each possible combination and type of image each optical element can produce. When I look at the ray tracing diagrams then reproduce the situation in the real world with myself as the &quot;object&quot;, all the scenarios make sense to me except one: when I as the object stand beyond the focal point of a concave mirror.  The image ends up as &quot;real&quot; and appears to be in front of the mirror. Now I understand that in the situation above, I as the object would stand at 6m and this would result in the image appearing at 12m. So if I placed a wall or screen at the 12m mark, the image would form on that surface (just like a movie theater screen).... at least I think I interpreted that correctly. But I still see myself when I look in the mirror?! If the image is supposed to form and come into focus behind me, what in the world am I seeing when looking at the surface of the mirror? I still see myself, just inverted. The surface of the concave mirror still has a reflection on it. It doesn't look quite like a normal flat mirror, in that the image doesn't really look like it's &quot;inside&quot; the mirror, more like it's right on the surface of it. It's really frustrating because every other possible arrangement of optical elements makes total sense to me, except this one. Any suggestions on how to think about it? Thank you for your time!
61859
This is something I just realised I don't entirely know the answer to, so I'm going to ask it here as I think it's interesting.  In most non-scientific writing on depth of field, diagrams generally show camera and subjects as being perfectly parallel, e.g.    However, is this a more accurate representation of the focal plane?    Are there ways to optically alter the shape of the focal plane?  Note: Obviously these diagrams are two dimensional, but I'm assuming in the second diagram the shape would be spherical with the sensor at the center.
106698
Context  Looking at previous shots I've taken, I see that when I'm indoors and shooting outdoors with glass in between, I sometimes get glare. I know that realistically if I can get outside, the shot looks a lot better but sometimes that isn't an option, or it is inaccessible.  The only way I've found to reduce glare is to remove the lens hood and put the lens right up to the glass but I'm unable to get different perspectives except ones tangential to the glass.  Question  Are there ways to mitigate or reduce glare, before post production? Related when is glare most predominant/likely to occur?  Related
20175
I have a variety of lenses in my camera kit. One that I do not have, and has me curious, is a fisheye lens. I mostly understand what it does: it captures an image with distortion similar to what you see through a door's peephole.  Given the distortion, are there any particular types of shots for which a fisheye lens is useful?
78250
I am trying to take pictures of large rugs. The rug size is about 10mx5m, and I'm  planning to purchase , and Canon 7D Mark II with Canon EF 50MM F/1.2L USM lens, since we need high quality images.  We want to set up a studio to take giga-pixel quality images of the large rugs for museum conservation purposes  Could you please suggest the best way for mounting the camera to the ceiling, and any other recommendations for my camera/lens setup, and required lighting? It will be  an indoor shoot. Just we want to setup a studio to shoot the large rugs.
12977
Hai.  I have a question, I switched from Canon to Sony a while ago and I found out that if I shot bright places, like the sky, the cloud that is supposed to be seen clearly, looks like a blown-out highlight (like real crazy), as you can see on my picture.  I have to set a low exposure just so the highlight is not blown out, and it’s only happening on Sony, not on Canon. On Canon the object is visible, but the background (cloud) is still seen all just fine.  Do you guys know what to change on the Sony to get that good look? Is it the setting or the lens? (BTW, I’m using a Sony 35mm f/1.8 lens.)
21574
For the start, I thought was orthographic, but when I used the orthographic camera, it didn't match up. Client say they want a so-called &quot;industry schematic&quot;, talking about a 135 degree look.  I found a trick to do this, which is using lattice. I align the lattice with the cube, and move the upper four points a little bit along the axis showing on the following image. But I want to achieve this by just using the camera.
34274
Okay, so I'm trying to grasp how the human eye will perceive the real image created for example by a convex lens. Take the upper image in this picture for example.    If you were to place a screen at the focal plane, you'd see the projected image, and the size relative to the original object would be as the arrows suggest. What would I see if I was standing in the focal plane? Would I see the image with the same size change? Would I see anything?  If I stood much farther away, would I see a "virtual image" (I know it wouldn't actually be virtual), that is would it look to me as if the object actually was in the focal plane, and was of the size of the arrow in it?
111662
I am wanting to venture into some extreme macro photography, specifically insects, such as . After doing some research I have believe that my 1::25 macro lens will be sufficient if I am to use some extension tubes (which I have bought).  I would like to shoot the in the wild, is this possible/likely? Or is this always a catch, then release style of shooting?  Regarding the link I've posted, would this be possible with a 1:25 macro and extension tubes? I have a set of three (21mm, 31mm and 13mm). How would you go about shoot a blue bottle for example? Surely they are going to fly away? Should I use a tripod or will that cause more of a hindrance than a help? Are there any techniques/tricks I could use to get a sharp focus on my subject?
108654
A friend of mine is thinking of buying a used medium-format film TLR camera (a ), and he showed me some of the test shots he'd taken with it.  I was struck by the curiously non-uniform bokeh in some of the photos, like this one:   (Subject's face blurred for the sake of privacy, since they're not my kids.)  If you look at the background, especially the trees at the top of the picture, you can clearly see that the bokeh is not circular but elliptic, and that the long axis of the ellipse seems to be orthogonal to the line from the center of the image.  It almost looks like circular motion blur, as if the camera was rotated during the shot, but the lack of blur in the foreground makes it clear that it's not.  I rather like the effect, especially the way it draws the eye to the center of the picture.  (It's not so effective in this particular shot, since there's no strong central subject for the eye to be drawn to, but in some of the other photos with a more central composition it worked really well.)  What I'm wondering, however, is what's causing it, and is there a name for it?  I can sort of see how it might arise from the way the light travels diagonally through the iris near the edges of the image, emphasized by the relatively large film format (my own camera, which I've never really noticed such an effect with, is a Nikon DSLR with a comparatively tiny APS-C sensor), but is that really all there is to it, or is there something more complicated going on?  And how could I deliberately achieve the same effect, short of switching to medium format myself?  Ps. Here's a close-up of the top of the photo above (click to enlarge):    The picture was taken with the Mamiya-Sekor 80mm f/2.8 lens.  Unfortunately, I don't know the exact aperture and shutter speed settings used.