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Forum: Mini-Challenges, Games, and Photo Stories
01-15-2012, 06:31 PM
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Skipping along
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Forum: Pentax SLR Lens Discussion
01-13-2012, 04:05 PM
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Some samples, wide open.
Focus on center right edge (Asahi/pentax logo). First AF, then move camera 1-2cm to avoid field curvature:
Focus on upper left AF point (Asahi logo):
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Forum: Pentax K-5 & K-5 II
07-19-2011, 02:56 AM
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Nice photo, Phil. The high iso capability of the K5 is really impressive.
I know everyone seems to focus on the fact that you can avoid camera shake with a shutter speed of 1/FL, but there are other reasons to bump your shutter speed, in particular to freeze motion.
As far as handholding ability, SR does help two to three stops, but as the number of megapixels in a camera goes up, the ability to hand hold it and get pixel level sharpness becomes increasingly more difficult. I feel like the rule of thumb that you use really depends (a) on the individual (how shaky are you really?), (b) on the pixel density of your camera and (c) on how much you pixel peep. Those who don't pixel peep are bound to be satisfied more than the rest of us.
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Forum: Digital Processing, Software, and Printing
07-17-2011, 01:28 PM
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It never matters what DPI the resolution field in the Exif is set to. All that matters is how many pixels are in the image. All 1200x1800 images are exactly the same resolution at a given print size, regardless of what the Exif DPI figure says. Pick the right number of pixels for your purpose, and don't worry about the value in the Exif field. I picked 1200x1800 because that's a size I use a lot. Enough for full screen viewing and hen some, or for a 300dpi print at 4x6 inches. But the dpi value in the Exif doesn't matter.
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Forum: Mini-Challenges, Games, and Photo Stories
07-08-2011, 09:47 PM
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tripper
get to stepping
le crooked smile
street
More street
repent
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Forum: Pentax K-5 & K-5 II
06-30-2011, 12:37 PM
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Well for such a trip and assignment it is good to take two camera body's. To be honest, I'm probably the only user on this forum who just trust's the K-5 and would not doubt about starting on this trip with 2 K-5's and some DA* lenses.
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Forum: Pentax DSLR Discussion
06-28-2011, 08:26 PM
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A) Measure a pinhead's surface area
B) Measure some angels' arses
C) Divide A by B. Elementary, eh?
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Forum: Pentax Compact Cameras
06-24-2011, 11:15 PM
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Define Image Quality?
There are people who shoot with full-frame camera's and put a lensbaby on the front. What about Polaroids? (I've seen entire shows made up of just them.) I guess no person who shot on 35mm film instead of medium format ever got a photo with good image quality?
I love gear talk as much as anybody else on here, but at the end of the day a great photo can come from any one of a variety of "cameras." At least that is the view I take.
If Sony provides the "Image Quality" that works for you, then be happy that you've found this out. I don't know why you would need to put down another product to justify your choice.
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Forum: Photographic Technique
06-22-2011, 10:27 AM
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I didn't find the MBP to be noticeably better than other non-Apple laptops I used. These included a Dell, a Sony, and an HP. But that's just my limited experience. As a graphic designer, I started out in 1997 using Radius ColorMatch displays, so my standards are pretty demanding.
Something else I noticed: In areas other than brightness and resolution, my 2002 Powerbook G4 Titanium had a better screen than my 2008 MBP. The color & brightness consistency across the screen of the Powerbook was much better. I compared them side-by-side and was shocked at how much more viewing-angle variation the MBP had. Unless I'm far away from it, I see color variation from top to bottom at any angle. Of course, they're both TN screens, so it only gets so good. In addition to having extreme color & brightness shifts at different viewing angles, TN panels can only produce 6-bit (per channel) color, which yields thousands of colors. Manufacturers use dithering to get "millions of colors." Deceptive advertising, IMO.
Apple Cinema Displays, newer iMacs, newer MBPs, and other high-quality displays use IPS panels. These are the best for color consistency and accuracy. MVA & PVA panels are sort of in between. They do, at least, have true 8-bit color. There's some brightness variation by viewing angle, but not very much color shift. At home I have a monitor with an MVA panel.
You can use this site to check your LCD monitor.
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Forum: Photographic Technique
06-22-2011, 09:05 AM
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My interpretation of RioRico's slight :) intolerance for the "purity" idea is that it's a bit of scorn an experienced person has for some of the relatively inexperienced, yet strongly-expressed, opinions. I myself am not nearly so experienced, but from the experts I've studied, they seem to have no hesitation manipulating an image. So where is the dispute?
It seems to me that complicating this discussion are the several streams of thought going on which some think are in competition, but really are merely different practices of photography.
For example, of course one wants the very best RAW file (or negative) since that will contain the most information and the most potential for creating the desired finished photo. When we were talking about Ansel Adams earlier, his approach was precisely that . . . his first and foremost objective was to obtain the best possible negative to work with. In that spirit, if one wanted to develop the ability to get the most out of a RAW file or negative, it is very useful to practice shooting with the intention of applying no PP, and so those posters recommending that practice are making sense (of course, once Adams had the best negative, he didn't stop there).
There are also various uses for photography, some for technology where accuracy of image is the goal. There are people simply recording snap shots to look at in their old age or show relatives, etc. My wife uses her cell phone camera to enhance her descriptions of what she sees while out and about. Anyone using photography like that will have their own priorities for processing, or lack of it.
And then there are those, many of whom participate at forums like this, who are shooting to evoke a feeling or appreciation by viewers . . . that kind of effort is the attempt to do art. Understanding how a camera and processing work are the tools we use to create, and in the quest for evoking feelings there is nothing out of bounds if it "works" the way we hope it will.
Now, to do art, is it useful to know how to create the best possible RAW file? Of course. Yet what about when the light is poor, or when you have just a fleeting moment to capture something happening? Should one pass up creative opportunities because one can't produce the perfect RAW file or negative?
So if RioRico seems intolerant of the purist idea, possibly it is because he knows that among experienced photographers there is no question about image manipulation, whether that is by lens choices, composition choices, exposure choice, DOF choices, or processing choices. I agree because when I look at a picture, I just want to be pleased . . . I don't care how the artist arrives at the pleasing photo.
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Forum: Photographic Technique
06-19-2011, 10:33 AM
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I'm perfectly sympathetic with PP as a means to create an artistic or even visually realistic image (like how mild hdr/tone mapping can make an image more like your mind remembers the scene) or drastically altering a image for effect but there are situations where precise recording of what was actually there is the goal. In such circumstances it is important to calibrate a tool before you use it - not afterwards- unless there is a good means of self calibration built into the scene.
Just a reminder - not an argument that one shouldn't PP to modify for purposeful effect. But it depends on the final purpose; substituting blue for brown eyes on a passport photo isn't quite proper I suspect while removing a scab from a make-up model's nose seems ok for selling makeup.
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Forum: Photographic Technique
06-17-2011, 08:57 PM
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Red Rock Canyon, Valley of Fire, Hoover Dam, Charleston Mountains, neon-sign junkyards and museums, casino shots (day and night), these are all pretty obvious. Any guidebook will point out the Kodak, er I mean Pentax Moment spots. Instead, do this: Find a desert wash / gully. Be there before dawn. Watch the colours and shadows change. Be there again at sunset. When you drive by at 100 kph, it's all just stinking desert. Walk slowly at twilight and it's alive. Don't forget the tripod.
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Forum: Photographic Technique
06-17-2011, 01:19 PM
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Steve, these are often asked questions, and even more commonly questions that people are afraid to ask for concerns of the answers not gelling with any sort of 'purist' model hoped for.
Not just the K-5 - sensors and films in general hardly have the DR and capability of the naked eye to 'see' the scene in vivid colour and contrast. So emphatically: no. The creative eye sees the way a photo can be produced from the scene in front of the photographer, even before the photo has been taken.
No.
Ridiculous to consider cropping as such. That would also mean that the camera's sensor/film size innately 'contaminates' the images for having the dimensions that it has.
No, no, no, not applicable. PP is not bastardising an image, insomuch as tennis is played by a talented pro who wants to hit the ball with a $500 racquet of his/her choice as opposed to a standard $50 one (as it is with lenses in photography). How far PP is taken determines the resultant image's appeal and talent of the photographer, not only in the capture of the image but in the processing of it.
Admittedly, changing the contents of an image in PP is somewhat different (and not what I'm talking about here), though it too has its place particularly in glamour photography with composite work.
There is no perfect photograph, only varying photographers' interpretations of the scene before him/her, each with their own value and appeal as seen by others. Perfection is elusive in photography, as it is in most professions, though there are degrees of allure or charm to a photograph that implies excellence in the art. But excellence can exist in many forms without being 'perfect'; perfection itself implies that there are objective criteria to attain that status (in art these are far more subjective). And since perfection only allows for one 'best' result, it is a self-defeating entity in photography given the variety of rendition and PP of a single scene that can produce differing reactions from viewers yet the same appeal.
I am convinced that the more a photographer knows the complete process of producing photographs, the more the PP becomes a valued part of the process as much as the initial 'seeing a scene with the mind's eye', and the photographic techniques involved in the capture of the scene. The foresight of seeing a scene with PP in mind to create a work of art is a great virtue not unlike that of a skilled architect or surgeon who sees the end result even before pencil is put to paper or a scalpel has made the first incision.
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Forum: Photographic Technique
06-15-2011, 02:31 PM
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I think a lot of people believe post processing an image somehow destroys the integrity of the photo and that they don't want to be a part of that. That it is a dishonest act of deception that misrepresents reality...
Just... ignore them, honestly. Every camera does post processing for you -- even if you shoot RAW your camera has settings dictating how it should treat certain information. To take direct control over this and do it on a computer with sophisticated programs is to me just another step in presenting your work. Certainly people can sometimes take it "too far", but that's not much of an argument against post processing by itself. You're creating an image, not dutifully reporting a summary of the photon activity in the area when you pressed the shutter button.
The way I see it, even the human eye-brain system is doing an enormous amount of post processing on the raw information that streams in from the environment, so who truly has the right to claim what an honest image is?
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Forum: Pentax SLR Lens Discussion
06-08-2011, 06:43 PM
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You might be mistaking a critical cost-benefit analysis as "demeaning" in many cases.
Just a thought. You arent the only one who makes that mistake.
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Forum: Pentax SLR Lens Discussion
06-06-2011, 05:22 AM
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Winder, I may be reading you wrong but you seem almost angry in your posts. I sure hope you're not. I'm sharing what I know about lens design, you're free to believe me or not, I can only give you my credentials and share the knowledge and experience I do have.
a smaller sensor allows for a smaller lens (better price) but not an easier design. There are little fundamental differences between designing a full frame or an APS-C lens.
Hoya is one of the biggest manufacturers of glass in the world, I have ordered from them and designed with their glass in the past. But thinking it can have any significant impact on how Pentax design their lenses is mostly wrong. There is about a dozen of major glass manufacturers in the world, each with their catalog of glass with different properties. When designing a lens, you look up the glass with the properties you want, and include it in your design, whatever manufacturer offers it. If Pentax limited themselves to Hoya, they would be unable to work, essentially.
Lens coatings improve transmission, but do nothing to reduce aberrations.
Computer design of optical elements is something I do everyday in my job. It has been around for some time... the first version of the Vivitar 70-210 was computer designed. You can even dab your hands at it by downloading the educational (free) version of OSLO, one of the most advanced lens design tools. The 450 pages manual is in fact an introduction class to optical design.
the process of designing a lens, nowadays, is like this:
1-look up existing designs (you can purchase CDs with 10 000 designs on them, look up any optical science magazines).
2-find the design closest to what you want to do
3-adapt its specifications (focal length, aperture, etc)
4-look at the aberrations involved, start to swear
5-play with the values, glass types, thicknesses, and so forth, until you find balance.
The art of optical design is all comprised in that fith step.
For the record, the 645D is a 10k camera competing with 40k cameras, so yeah, it's economical.
We are now exiting optics territory and entering marketing/sales territories. I am not trained in those fields. I will use my logic, such as it is, and propose that with all the talent we know is available at Pentax, if a lens such as a 200mm f1.8 WAS a good and profitable move, it would have been done already.
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Forum: Digital Processing, Software, and Printing
06-03-2011, 12:10 PM
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In the library module's catalog pane, click on the 'All Photographs' bar. Select any photograph in preview pane. Hold the 'ctrl' key and press the 'a' key, this will select all photos. Click 'Export'. In the export dialog 'Export to' dropdown menu, chose 'same folder as original photo'. Check 'add to this Catalog' check box and chose your format, quality and other options.
After exporting, Use the library filter to filter the catalog by file type and remove the raw files.
If you don't have the room to do all the photos at once, you will have to do them in smaller batches. The export process will probably take a very long time.
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Forum: Pentax SLR Lens Discussion
06-01-2011, 10:20 PM
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I posted two photos of the same scene where it's easy to distinguish between the FA 43 vs. DA 40 (harsh vs. smooth background bokeh).
Here's an interesting bokeh roundup:
Bokeh Test |
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Forum: Pentax SLR Lens Discussion
06-01-2011, 04:45 PM
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To use the guitar comparison....I suck just as bad on my $3500 Masterbuilt Telecaster as I do on my $800 Telecaster.
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Forum: Pentax SLR Lens Discussion
06-01-2011, 02:30 PM
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Don't even get me started on audiophiles. Before I spent my time learning about photography on forums (amazing how much I have learned from you people in the last year), I spent my time learning about guitars on forums. Guitar audiophiles are *true* emperor's new clothes victims. They're the same people who spend 100s of dollars on oxygen free wires, and buy hand-made amplifiers because "point to point wiring is made with a better type of metal that sounds better".
On guitar forums, I learned something after about a year - it's not the pickups, it's not the amp, it's not the room, it's your fingers. It's all in your fingers. Flash forward 8 years, and I *can* make a bad acoustic sound good. Tone is in the fingers, and I would imagine that pixie dust is as well.
I've really done some thinking about this. I like, but do not love, my FA 77. No question that it's a great lens in a technical sense, but I do not connect with it. Therefore, very few pictures I take with it have any magic. Looking through my library of pictures, other lenses really *do* have magic (at least when compared with my other work).
The one lens that has the most hits is my K55 1.8. There is no good technical reason for this. It's kinda soft wide open, the bokeh is so so stopped down, and it's not exactly a pleasure to work with in an environment where the lights are rapidly changing. I find it flares up too much, not the best for action, etc.
However, for whatever reason, I connect to the world when I'm looking through that lens. I see in a way that makes sense to me, and I'm able to capture the important stuff (subject / light) more naturally when the K55 (and similarly, the FA 50) is attached to my DSLR. I think it's due to the focal length, mostly, but I'm sure rendering comes into play as well.
The point is that a lens *can* have pixie dust... or maybe more accurately, a lens can *pull* pixie dust right out of you. If you connect with the FA 43, the unique way of separating the subject from the background with a very unique mix of sharpness and impressionistic bokeh, the focal length - then you are going to take some magical pictures. And you will attribute that magic to the lens... but really, it's just the relationship you formed with the lens!
This also accounts for the disagreements about the *best* FA ltd (or DA ltd). That's going to vary a lot depending on how *you* see the world through a camera. Some people want the 31, a naturalistic point of view with a very pleasing blur. Other people want the 43, a sharp-as-hell lens with a "sensationalized* rendering that zooms in just enough to isolate an object. Other people want the 77, so they can literally cut an object out of spacetime and present them in an ethereal light.
Clearly we all have different goals. Maybe I'm thinking about this too much, but I liken it to music. Everyone has a natural tempo. Some people are adverse to fast music, they prefer grungy blues, hip hop, or soul at 80 BPM. Others prefer pure stimulation, seeking out music like metal or electronic music in the 140 bpm range. And of course there's the pop fans who like it right in the middle, not to warm and not too cold. No one can convince the other that their feel is the right feel. I know I get bored as hell listening to folk music, but my good friend gets downright irritated when I show him some tech house. I don't think either of us are right.
So this was a very long winded way of saying: I agree with Marc. It's pretty damn subjective, and the elusiveness of pixie dust might be due to the fact that it's contingent on you developing a relationship with your lens, and as we all know, love is a personal thing.
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Forum: Pentax SLR Lens Discussion
06-01-2011, 12:08 PM
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Nice post, and I'll use the above statement as the baseline for further comments.
In almost exactly the same way, there is a special quality to Coke as compared to Pepsi. If we knew the formulas, would could put that difference into words just as Jun did in explaining the FA Limiteds. But that doesn't make all people who prefer Pepsi wrong, nor would it mean that those who can't tell the difference, or who can tell the difference but still don't *prefer* one over the other, are missing out on anything particularly important in the grand scheme of things.
But still, in the end, subjective. It's like this in almost all fields. Recognizing and appreciating differences in the musics of Bach, Beethoven, and Brahms (and the differences *within* their output) is similarly a matter of trained and attuned perception. The differences are real. But it's still the case that experts might disagree on preferences, or simply not have preferences. I can tell the difference between these three as easily as you can presumably tell the difference between the FA43, DA40, and FA50. But I won't claim that just because on any given day I might have a preference for listening to one over the other, that this has any significance beyond being just that - one person's preference on one given day.
BTW, I'd claim that the differences being discussed here are akin to the differences between Beethoven and Brahms than between Beethoven and Bach, in terms of magnitude and significance. That is, relatively subtle.
You left out category 4: those who think lenses matter and acknowledge the "special" qualities of certain lenses, but don't recognize that being "special" makes them "better" in any objective sense, because such things are subjective and not objective. Most of these people also happen to believe the magnitude of these particular differences are pretty small, and have trouble making the distinctions reliably themselves. But that's kind of beside the point.
To some extent, you could lump these people (obviously, I am referring to myself) in with class two, and in that case:
I'd have to put myself in class 2a. But I would not be one to try to convince anyone that the lenses that are special to me must necessarily be the ones that are special to anyone else. In other words, I would be pointing out that the people in class 3 above could be divided into:
3a. Those who recognize the subjective nature of their own preferences
3b. Those who find it necessary to deride those who point out that such preferences are subjective
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Forum: Pentax SLR Lens Discussion
05-31-2011, 09:13 PM
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I'll not bother to get specific with my own breakdown, but I've slowly come round to the opinion that in the recipe for a good photo, the photographer is maybe third down on the list of ingredients, behind light and lens. I'm certain no one would agree with this bit of sacrilege.
And it's complicated by the fact of the photographer's direct influence on both light and lens. But I have many photos the impact of which would have been reduced by 95% or so had the light been different. Certainly, even if we reduce the photographer's contribution down to something as low as 10%, it's a critical 10%. For example, let's say chocolate chips make up 10% of a great cookie. We cannot simply replace them with rabbit turds and expect to get a result that doesn't leave one with the aftertaste of rabbit turds.
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Forum: Pentax SLR Lens Discussion
05-31-2011, 03:06 PM
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Yes, but that's obviously a single-blind.
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Forum: Pentax SLR Lens Discussion
05-30-2011, 10:46 PM
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Nonsense. Glorious Soviet optical lenses were designed to deliver the greatest number of megatons of pixie dust.
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Forum: Pentax SLR Lens Discussion
05-25-2011, 10:15 AM
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I actually decided to take my lenses apart last night to try and measure the actual amount of pixie dust each one had. It turns out that the FA limiteds indeed do have a fair amount of pixie dust in them. The FA31 has 15.6 micrograms, the FA43 had 27.2 micrograms and the FA77 had exactly 18.0 micrograms of pixie dust contained in the glass itself. By contrast, I was only able to find 0.2 micrograms of pixie dust in the DA40/2.8 and less than 0.1 grams in the DA35/macro. My best guess at this point is that the DA limited lenses aren't suppose to have pixie dust in them but perhaps there was some overspray in the factory during the pixie dust application process for the FA limiteds and some pixie dust was accidently deposited onto the DA limited glass before they were assembled. Hopefully tonight I'll have a chance to take the rest of my lenses apart and see if the I can find any other lenses with any pixie dust in them. I suspect I may find a little in the FA*85 :rolleyes:
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