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Forum: Pentax DSLR Discussion
12-29-2009, 03:04 PM
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Andras, thank you for the pointers. Both cameras were unfamiliar to me the first time I tried them out. Now I am using the AE workaround fairly regularly. Not so with the AE-AF linking though, becaues it gave me bad exposure far too often. I had to delink them.
Anyway, here is a fantastic explanation of why Nikon D40 with its 420-pixel RGB AE metering gives way way better photographs of people: (I don't know how to link URLs, so here is a quote from Imaging Resource D90 review - D40 uses same AE metering):
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Face Detection in Phase-Detect AF?
Here's a new wrinkle we were frankly a little surprised to hear about: The Nikon D90 can actually use face detection when in normal auto-area phase-detect AF mode. At first, this sounds like an impossibility, and it would be for a purely conventional phase-detect AF system. After all, how could the AF sensors tell whether they were focusing on a face or any other object? All they see is a signal that indicates how far in or out of focus their part of the subject is: There's nothing that would indicate what type of subject they're looking at.
This is where the 420-pixel RGB sensor comes into play again. It obviously doesn't have anywhere near the resolution of the main image sensor, but there's probably enough to give at least some idea of where a face might be in the image. We don't know the details of how the 420 pixels are arranged, but if they were in an array with a 3:2 aspect ratio to match the overall frame dimensions, that would be an array on the order of 25 x 17 pixels in size. Pretty paltry by camera image sensor resolution, but perhaps enough to detect a skin-colored blob against a differently-colored background. In closeup portraits, this is also probably enough resolution to figure out what part of the subject corresponds to an eye vs. a nose.
Of course, as noted before, the RGB sensor itself doesn't collect any distance information, and as such, can't directly control focus operation. In other words, you're still only going to be able to set focus based on areas covered by the AF points themselves. But what the RGB sensor data can do is to help the AF system decide which of the AF points to pay attention to.
Playing with a prototype of the Nikon D90, we found this to work surprisingly well. In auto-area AF mode, if we arranged objects to have several both covered by AF points and at equal distances from the camera, the camera pretty reliably chose the AF point lying over a face. Even more impressive, if we composed a portrait shot with several AF points on the subject's face, but only one over an eye, the camera picked the eye more times than not. (It seemed pretty accurate, but we'll have to spend more time with a production sample before we can give any idea of how reliable this AF system feature is. Nonetheless, what we saw struck us as both impressive and useful in actual shooting situations.
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Hope this technical explanation clarifies what I mean by my layman's description "Pentax AE+AF is dumb comapred to Nikons and Canons when taking snapshots of people".
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Forum: Pentax DSLR Discussion
12-29-2009, 01:46 PM
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I know EXACTLY what you mean, I had the same feeling when I was comparing a friend's Canon T1i with my Pentax K-x head to head. Kx images looked terrible enough to make my heart sink :fedup:.
So we sat down at the local bar with a difficult bright lights + dark seating and I started experimenting with both cameras for a few hours and now I have a work-around :cool: : Bottomline is, Pentax AF and AE metering algorithms are really dumb compared to Canons / Nikons in a snapshot situation. Hate to say it, but it's true. I feel that Pentax algorithms act like an engineer, trying to get the best image parameters, while Canons and Nikons act like marketing guys who make people in your snapshots look good.
Here is my workaround for snapshots: Switch the AF to 5-point instead of 11-point and keep the subjects close to the center. Now experiment with AE metering mode, till you find the right "look". For me it is usually center-weighted metering in challenging direct sunlight or dark areas. As a downside you lose freedom in framing your subject, but you can crop the photo later to your liking thanks to the 12MP resolution.
Try these two settings out, let me know what you think.
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Forum: Film SLRs and Compact Film Cameras
12-14-2009, 01:24 PM
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Ash and Nesster, appreciate your guidance on this one.
My original lens is a Cosina 35-70mm macro, I also picked up Penatx M 50mm and 28mm on ebay last year. All the lenses are sticking - I tried to shave off a milimeter of plastic protrusion off of Cosina's back, but that didn't do enough to help.
I will take a look at the foam kit that you recommended...
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Forum: Film SLRs and Compact Film Cameras
12-14-2009, 12:57 PM
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Hey all,
I just upgraded to a K-x but still love my film SLR dearly. However lately I have been experiencing a problem with the mirror: When I release the shutter, the mirror clicks up and just stays there. I have to remove the lens partially, and then mirror clicks back down. Feels like it is getting stuck on the lens.
Has anyone experienced this issue? Is there any solution to it?
Thank you in advance!
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Forum: Pentax SLR Lens Discussion
12-09-2009, 06:59 PM
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Oh I was so happy to see the lightning quick image results with my new FA77, and thought to myself that may be this lens is so awesome that it doesn't need much correction at all. On the other hand my kit lens takes about 2 seconds to correct after pressing the shutter. Now I know :-((((
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Forum: Pentax SLR Lens Discussion
12-09-2009, 06:55 PM
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I think I would try out the new HD video feature. The blurry manual focus should negate my blurry, drunk vision resulting in crystal clear footage.
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Forum: Pentax SLR Lens Discussion
12-08-2009, 08:01 PM
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M8O, thanks for pointing out PBase - I did not know that resource before.
I am still shopping around for a FA43, although FA77 and Schneider Kreuznach D-Xenogon 35 (35mm f/2 AL rebadge) are en-route! Will post some pictures after I experiment with them over next couple of weeks...
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Forum: Pentax SLR Lens Discussion
12-05-2009, 01:51 PM
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OMG Kristoff, I was thinking of Leica S2 too!! My party shots would look like Vogue centerfolds!! The shop next door didn't have it though, and I was like what the hell, let me get the white color camera!!! Now I totally stand out at every partaay I go to because everyone else's SLR is black, isn't that like so cool?!!?
Oops I misspelled your name again. Am I hurting your feelings every time I do that?
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Forum: Pentax DSLR Discussion
12-05-2009, 01:44 PM
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I suspect it is the mirror - especially during live-view, when mirror locks up it is making a disheartening flapping sound every time I move the camera :-(((( wish they had used stronger mechanism to prevent this.
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Forum: Pentax SLR Lens Discussion
12-05-2009, 01:36 PM
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Yep, back in the days of frat parties I actually had the Pentax Optio 43WR waterproof, shockproof camera. Hurl-proof! Also came in handy during drunken rafting trips at Ohiopyle.
Now I am down to a more reasonable binging levels and people around me hurl a lot less, I felt that SLR with FA can be a safe bet. And thus the upgrade!
LOL @jsherman999 and @mastoberg!!! Spot on advice!
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Forum: Pentax SLR Lens Discussion
12-05-2009, 01:29 PM
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Haha thanks for the support FH, I went ahead and tagged my remarks with tag just to make it clear to those who don't get it.
I will give the 35 Macro a shot as well.
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Forum: Pentax SLR Lens Discussion
12-04-2009, 05:22 PM
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Visiting websites different than you does not make me a troll Kristoff. One of my friend's father is a well-known photographer in my neck of woods, and I visited his FB group to see his images and lenses. Anyway, other than a personal attack, did you want to contribute something else to this discussion?
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Forum: Pentax SLR Lens Discussion
12-04-2009, 04:36 PM
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Folks, one clarification: "me" photographs don't mean self-portraits, it means that you hand the camera over to someone nearby and ask them to take a picture. At every party you see these group sessions, where 4-5 people hand their cameras to the least photogenic person and do a 1-minute photoshoot before getting back to binge drinking.
I see some people commenting or ridiculing me for judging a lens' quality from Internet pictures. I am not judging the quality, I am judging the look or the emotional impact. And as @Nesster correctly observed, candy-coated pictures with people or animals tend to get more attention from the masses. Professional or non-professional, print is slowly but surely being replaced by Internet - this will require new approaches to testing and comparing lenses. My approach is no more or no less valid than any pixel-peeper's Imatest analysis.
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Forum: Pentax SLR Lens Discussion
12-04-2009, 02:29 PM
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Thank you all for understanding the angle I am coming from and not flaming me out!
@Ash and @Nesster, I realize I wasn’t very specific about image characteristics so let me add some detail here.
First off I selected the FA series lenses and disregarded DAs, because I plan to upgrade to a full-frame SLR as soon as Pentax releases it in future.
The FA77 was an easy elimination because it acts as a 115mm lens on a cropped sensor that we all have now (and for next year or two at least) – this kind of long focal length, handheld in dark indoor environments (read: parties) after a couple of drinks gives blurry pictures no stabilization system can salvage. During daylight and sober shooting, it ends up being too narrow FOV to show off the general awesomeness surrounding the “me”.
So the race was on between FA31 and FA43, and I sat down with a few friends to go through pictures on Flickr. Every FA31 opinion raved about the level of detail, sharpness, and buttery smoothness, but none of this was visible to any of us at 800x600 or other internet-friendly resolutions. The “me” style pictures on Flickr from amateur DigiSLR+FA31 combo looked very flat, as if they were from a Sony T-series cameras girls carry around in their purses, according to one opinion.
On the other hand, more of FA43 Flickr images seemed to have a more immediate impact on my friend-advisers. The very-shallow DOF and the corner-softness everyone seems to complain about simply emphasized the “me” in the picture, while the wide angle FOV hints at the locations the subjects were gracing with their presence. And most pictures with stepped-down aperture showed greater vibrance. Chromatic Aberrations from FA43 that PhotoZone.de complains about can be corrected in-camera by Pentax Kx, so they were a non-issue.
These reasons made me prefer the FA43 initially, and the compact size and weight that can be helpful in backpacking trip and hiking sealed the deal for me.
@David, once upon a time I too enjoyed the art of photography with my fully-manual film SLR I had for a decade. But the time I spend on taking pictures of sand-piles in Mohave and flowers in Ohiopyle is being cut down by the time I am spending now on Twitter and Facebook.
And no, the kit lens or iPhone will no do because it can not emphasize “me” with shallow DOF interchangeable lenses can provide!
@Kenyee – exactly!
@DragonFly – I tacked on the citizen comment just to save myself from flaming. Thanks for reading!
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Forum: Pentax SLR Lens Discussion
12-04-2009, 12:36 PM
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Hello all,
I observed something very interesting about the dramatic change in “Photo Consumption Habits” these days, and how that turns the long-established assertions on their head. I thought I will share my thoughts with you all in an op-ed style write-up, and hear your comments. Please don’t flame – I am using words like “me” and “we” just as a generalization.
I wanted to buy FA Limiteds for my new Kx, so I started out by almost memorizing reviews from numerous sites like www.PhotoZone.de and our own PentaxForums, and scanning through every picture on www.PentaxPhotoGallery.com. The opinion seemed unanimous: FA 31mm is the best Pentax lens ever made.
But before biting this very expensive bullet, I decided to check out pictures taken by these lenses on www.Flickr.com and Facebook photography groups, which is probably a better representation of what new-generation, non-professional photographers can do with these lenses. And THAT totally reversed my conclusion – I came out wildly preferring the Pentax FA43 lens.
Hunting for an explanation, I realized that all wide-spread reviews and opinions are from people whose “Photo Consumption” is very VERY different compared to everyone I know. Every good picture we take ends up on Facebook, and all my friends check them out on their laptops and iPhones. We broadcasting anything weird or funny we see using Twitter apps on phones (I will upload an example in my gallery later tonight). We never print, and in our 800x600 pixel world old pixel-peeping standards of quality are meaningless. The “look” of the picture is the only thing that matters, and Photoshopping helps your popularity among friends.
Even the content of the photographs has changed: We are interested in only “me” centric subjects (me at a party, me at someplace cool, me with someone cool, look what me made, me at a bigger and better party than you), sort of like this German Pentax Kx commercial: http://www.youtube.com/watch?v=UOR-qVVcG5k. Categories like macro and landscape are dead for us; even classic portraits are on life-support reserved only for weddings and parents. Taking pictures of objects, flowers, buildings, or sand-piles doesn’t matter, because “If I am not in the picture, why not just download pictures from National Geographic or some website, where a professional photographer did a much better job than I could ever hope to do?”
And no, we are not a bunch of bird-brains mooching off our parents. Most of us are working hard, and are doing quite an alright job being a good citizen and all that.
Thanks for reading!
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