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01-14-2007, 08:31 PM   #16
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QuoteOriginally posted by bdavis Quote
Huh? Yes, I am an American. I don't see how my geographic location would make it easier/difficult to prove that the camera is faulty. (As you said, it would show up in the pictures!) It also doesn't make it possible for me to snap my fingers and magically make a new body appear. I'd have to work with my source/dealer/service center just like everyone else. As I said before, my verifiable, objective, repeatable issues would be seen by whomever I took the camera to.
You are very naive if you think that laws and rules are the same everywhere.

Also interesting what would you do if your source/dealer/service center would just refuse to agree that camera is defective? You can show tham hundreds of misfocused pictures they'll just say: user error, focus accuracy is in tolerable margin and so on. Maybe it's hard for you to believe that it can be like that, but it happens in Eastern Europe, Russia. Then it's much easier to look at those internet sources (have you noticed, solution comes from Russia?) and to fix problem yourself.


Last edited by Edvinas; 01-14-2007 at 08:37 PM.
01-14-2007, 10:08 PM   #17
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QuoteOriginally posted by Edvinas Quote
You are very naive if you think that laws and rules are the same everywhere.

Also interesting what would you do if your source/dealer/service center would just refuse to agree that camera is defective? You can show tham hundreds of misfocused pictures they'll just say: user error, focus accuracy is in tolerable margin and so on. Maybe it's hard for you to believe that it can be like that, but it happens in Eastern Europe, Russia. Then it's much easier to look at those internet sources (have you noticed, solution comes from Russia?) and to fix problem yourself.
I don't know about any country but canada, and around here it all depends on SERVICE.
sometimes if you buy from a big chain store that the sales people make commision, then there is a possiblility that you have to go way out of your way to prove that something is wrong with your equipment. sometimes this is how places cut costs in order to make their products cheaper.
I have heard more then one "horror" story about a chain store called futureshop.
some stores will let you take it back for one dead pixel, and others, especially sales person without a lot of knowledge in the field, will tell you it is nothing wrong with it.

I think Edvinas has some truth to what he was saying about it being easier to get things fixed in USA. American consumers seem to not put up with defective equipment as well as other places. Just read the papers. Class action suites seems to be a common thing when companies fail to deliever a quality product. this in turn helps to make sure that products are of higher quality (companies think twice about shipping defective products).
with the right people, it is not to hard to get a lawyer to help you get one going.
In other countries, including canada, this type of thing just isn't entertained in the courts as often.

class action suite IMHO does 2 things

1) help keep quality control in the hands of consumers

2) raise the price of products indirectly by lawyers fees

No american bashing here, just sharing an opinion.
01-14-2007, 10:11 PM   #18
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QuoteOriginally posted by Edvinas Quote
Good for you in USA. In some other places you would have really hard time trying to prove that your camera is front/back focussing. And not necessary succesfully.
I read that in Australia - where you are based Edvinas (?) retailers offer a 45 day return policy, better than the USA!
01-14-2007, 10:40 PM   #19
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I would also add that I am in Melbourne, Australia and if you have a real problem CR Kennedy's support is extremely good (local Pentax distributor)..

P.S. All new Pentax gear has a 1 year warranty here..

If you want to try and 'fix' things yourself then go ahead, but you void the warranty... and RH didn't provide a true fix of anything in that blurb IMO... though I admit I am not one of the 'suffering' few who needs a fix ;-)


Last edited by joele; 01-14-2007 at 10:54 PM.
01-14-2007, 11:11 PM   #20
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Before this degenerates into actual name calling lets take a serious look at the conditions of the suspected back/front focus, lets review the manufacturers directions and warnings concerning extreme operating conditions and lets, for a moment, do a little independent thinking. Lets also examine the credentials of the testers.

Before we can fix a problem under the product repair/return conditions of any country, we must actually have a problem.

Conditions: maximum aperture, minimum focusing distance, moderate or low light. In the case where we use the edge of a book, very low contrast. In the case of the Jackson test, many long parallel lines.

From the manual: Pg 66:

The auto focus mechanism is not perfect.

Specific problem areas: (a) Low contrast, (b) low subject reflectivity, (d) high subject reflectivity, (e) strong vertical or horizontal patterns, (f) multiple subjects in foreground and background.

Thinking: paper is not the most reflective material on the planet--too hard on the eyes when one must read the type found on the sheet. So it's actual reflectivity is more a function of the lighting; keep this in mind. The book edge test gives auto focusing problems because of (b), (e) and (f). The Jackson test is problematic with (b) the paper, (d(0 the ink, (e) and (f).

Testors: mainly photographers and internet geeks. Any actual scientists, engineers or skilled optical technicians? Any mathematicians or statisticians? I'd accept either a college degree or a lifetime of hands-on experience; any takers?

{Best not to try to fake this as far as I'm concerned: I am both degreed and 20+ years experienced as an engineer. Education includes sufficient credits, continuing education and experience to earn 2nd, 3rd and 4th degrees in mathematic/statistics, chemistry and world history; including graduate level studies I qualify for 4 additional minors: chemistry, US history, physics and computer science. Fluent in 7 or 8 computer languages; specialize in system modeling and system fault analysis. Run my own business. Hobbies besides photography include computer building, amateur radio, telescope making, orienteering/geocaching, extensive reading and walking the dog. FYI: my daughter may be young and inexperienced-I wouldn't go so far as to call her naive--I am none of these descriptors.}

So, we have a group of artists performing suspect pseudo-scientific testing known to fail under conditions far short of normal operating parameters. (How often will you be wide-open at minimum focusing distance with low contrast subjects and poor or questionable lighting?) We have no collected statistics except for a handful of alleged failures of such test. No measurements, no controls for the scientific method, no objective testing.

The manufacturer with both qualified personnel and suitable testing equipment and procedures is unable to reproduce alleged problem.

As someone qualified to do this type of testing, as someone who has done this type of testing properly and as someone who knows what results this type of testing should produce the 'testing' of Ricehigh and similar individuals is suspect. Results are misleading; recommendations are ridiculous. In short front/back focus based on the Ricehigh 'hogwash' is essentially a non-issue.
01-14-2007, 11:12 PM   #21
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QuoteOriginally posted by Edvinas Quote
You are very naive if you think that laws and rules are the same everywhere.
I've got my eyes wide open, Edvinas, and I don't happen to see that I've got any particular advantage due to my citizenship, or that residents of other countries really have any disadvantage. Heck, I didn't even get to use one of those lousy, unfair to the rest of the planet, Pentax USA rebates when I bought my setup. Man...I had to pay full retail! All that money, and my gear doesn't even make my tea in the morning.

If my alleged naiveté is so evident, why don't you try to educate rather than hiding behind the flag of your choice, pathetically insisting that you've got it bad in your neck of the woods? To answer your question, no, I haven't seen ANY solutions coming out of Europe or Russia (or America, Asia, and Never Neverland). I haven't seen any legitimate, full blown problems to have solutions for, either.

(I have, however, seen a loudmouth minority work the internet communities into a tizzy. Misinformation, misinterpretation, myth, and many flaming dumptrucks of bad advice abound for those who refuse to accept lack of skill and practice, as well as the filing of manuals in circular cabinets, as the reason for poor photographs.)



Randy, trust that many terrible products make it to market without a class action suit ever being brought against the manufacturers. The US has an awful amount of litigation, but there really are much better means of quality control.
01-15-2007, 12:46 AM   #22
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QuoteOriginally posted by superfuzzy Quote
I read that in Australia - where you are based Edvinas (?) retailers offer a 45 day return policy, better than the USA!
Nope, I am talking about Eastern Europe.

QuoteOriginally posted by joele Quote
I would also add that I am in Melbourne, Australia and if you have a real problem CR Kennedy's support is extremely good (local Pentax distributor)..
P.S. All new Pentax gear has a 1 year warranty here..
Well, maybe it is good, but they don't service equipment under warranty which is purchased outside Australia. Market division into regions sucks

QuoteOriginally posted by joele Quote
If you want to try and 'fix' things yourself then go ahead, but you void the warranty... and RH didn't provide a true fix of anything in that blurb IMO... though I admit I am not one of the 'suffering' few who needs a fix ;-)
No, thanks, I don't feel qualified for that, however I've read that people sucessfuly adjusted their focus to fix FF/BF problem.
01-15-2007, 05:24 AM   #23
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QuoteOriginally posted by jfdavis58 Quote
Before this degenerates into actual name calling lets take a serious look at the conditions of the suspected back/front focus,
Whist you say you don't want to see name calling, you just do it extensively in your this post (and the last posts in this thread). Just how many times you have called my name in your this post?

QuoteQuote:
lets review the manufacturers directions and warnings concerning extreme operating conditions and lets, for a moment, do a little independent thinking. Lets also examine the credentials of the testers.

Before we can fix a problem under the product repair/return conditions of any country, we must actually have a problem.
(snipped)
Assuming users who have reported FF or BF problems are using their cameras in the extreme conditions as stated in the user manual are groundless pure assumption and imagination. I don't think all those reporting users can all have user errors like you supposed and don't know how to operate their gear at all.

QuoteQuote:
{Best not to try to fake this as far as I'm concerned: I am both degreed and 20+ years experienced as an engineer. Education includes sufficient credits, continuing education and experience to earn 2nd, 3rd and 4th degrees in mathematic/statistics, chemistry and world history; including graduate level studies I qualify for 4 additional minors: chemistry, US history, physics and computer science. Fluent in 7 or 8 computer languages; specialize in system modeling and system fault analysis. Run my own business. Hobbies besides photography include computer building, amateur radio, telescope making, orienteering/geocaching, extensive reading and walking the dog. FYI: my daughter may be young and inexperienced-I wouldn't go so far as to call her naive--I am none of these descriptors.}
What's the point here? I can't get it. Pardon?

QuoteQuote:
So, we have a group of artists performing suspect pseudo-scientific testing known to fail under conditions far short of normal operating parameters. (How often will you be wide-open at minimum focusing distance with low contrast subjects and poor or questionable lighting?) We have no collected statistics except for a handful of alleged failures of such test. No measurements, no controls for the scientific method, no objective testing.
I'm afraid that you've pure conjecture here.

QuoteQuote:
The manufacturer with both qualified personnel and suitable testing equipment and procedures is unable to reproduce alleged problem.
Then, all the cameras will be perfect, there is simply no need of any servicing and no warranty is needed.

QuoteQuote:
As someone qualified to do this type of testing, as someone who has done this type of testing properly and as someone who knows what results this type of testing should produce the 'testing' of Ricehigh and similar individuals is suspect. Results are misleading; recommendations are ridiculous. In short front/back focus based on the Ricehigh 'hogwash' is essentially a non-issue.
The use of your word "hogwash" imposed on me personally is inhuman and uncivilised, in addition to your numerous finger pointing to me already. I can't imagine how a self-claimed highly educated person can attack other without any reason in such a way. I deserve an apology from you. I don't know you in any way before and I can't understand why you must treat me like that.

Also, I am sure that you just have NOT read my article before you have jumped on me seriously in your several posts. I just wish to ask: what tests I have done? and what recommendations I have made? How come they are "ridiculous"??

01-15-2007, 05:29 AM   #24
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QuoteOriginally posted by -=JoN=- Quote
daily reports? i'm here everyday, and it's like once in a blue moon someone posts up a focus problem.

and i thought they were isolated incidents...

man...seriously...enough w/ the technical stuff, and just take photos...
The reports come from many places, not only here. Also, I state clearly in the beginning of my article that it is "regardless of brand"!

Afterall, those FF/BF reports are numerous.
01-15-2007, 05:39 AM   #25
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Manual focusing by eyes with modern DSLRs are not easy and it cannot be more accurate than AF with viewfinders of smaller magnification. That says the K10D will MF better than the K100D, but it is still not quite good owing to the following two factors:-

1. Its viewfinder is still small with the 1.5X factor (0/95/1.5 = 0.63);

2. The super clear focusing screen is actually mostly transparent than the old days ground glass matte screen which can be relied for MF.

Well, one can install the expensive Katz-eye screen, but then the exposure system is affected, owing to the loss in light to the MF screen, in particular the central split prism absorb more light - and the central segment of the metering cells is affect most seriously.

Nonetheless, your mentioned technique of narrowing down the MF range "little by little" is the right thing to do, I think.

QuoteOriginally posted by Simon Quote
It is mainly because of the potential for focussing inaccuracy that I have until now avoided auto focus SLRs (accepting AF in P&S cameras). This extract (by Izumi Taniguchi) from the Pentax Web site a reasonable (in my view) and pragmatic response to criticism about auto-focus inaccuracies...

Take advantage of the quick-shift focus function for final, minute adjustments

Remember that, no matter how advanced your camera’s AF system is, your eye is always the most reliable tool in focusing. It takes a great deal of time and trouble to do everything from the start with manual focus, but an effective combination of autofocusing and manual focusing can offer tremendous benefits.

Such benefits are all yours, if you own a PENTAX digital SLR camera and a PENTAX interchangeable lens equipped with the quick-shift focus mechanism. Incorporated in all PENTAX digital SLRs, the innovative, user-friendly quick-shift focus function makes manual focus adjustments simple and effortless: While keeping the shutter release button at the half-depressed position, rotate the focus ring of your lens to make final, minute adjustments manually from the initial autofocus position. Thanks to the bright, clear viewfinder featured in all PENTAX digital SLRs, this PENTAX-original function is an effective and efficient aid for your focusing operations.

When you have difficulty in making such minute adjustments by the eye, there is a simple, effective technique to assure sharp, crisp focus on your subject. After reaching the manual-focus stage, manually shift the focus ring little by little, and take an image after each shift. You will end up with several images with slightly different in-focus points, so choose the most accurately focused image later. Called “focus bracketing,” this technique is commonly used by professional photographers.
01-15-2007, 05:44 AM   #26
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I'm afraid the case is not that simple as you suggested. Firstly, Pentax or her agent may not acknowledge problem; Secondly, they will try to repair the problematic gear than to replace them, usually for a prolonged period and this similar cases can be dragged on for a long time. Thirdly, even they replaced the body (they did it for me for two times - for a *ist D and another *ist DS), do you think that the case can be resolved? (if all the bodies are just the same??)

QuoteOriginally posted by bdavis Quote
Hmm, if my camera had focusing issues--verifiable, objective, repeatable (by ANYONE) focusing issues--I'd send it back. I would know it had a problem, and would get a new one; no muss, no fanfare, no gratitude to a questionable internet source, just a new body.

One of these days, I'd really love to get my hands on the dud, because I'd take it apart. Unfortunately, these duds seem to be in short supply (gee...how can that be? Is it likely that there just aren't that many? Is it just easier for the manufacturer to replace a camera for a hysterical owner rather than convincing them the the problem is user error?), and its unlikely that I'll ever get to do it.
01-15-2007, 05:49 AM   #27
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QuoteOriginally posted by rfortson Quote
Thanks RH. Looks like some interesting reading.
I totally agree. I'm not sure I understand the earlier dissent or proclivity against information, but I for one applaud it. My main hobby is auto racing. In order for me to be the best racer possible, I need to collect and use as much information as possible about my sport / hobby. While photography is obviously more creativity-based, there exists technical aspects to it of course. With a better understanding of these technical aspects or limitations, it can only serve to make one a better photographer.
01-15-2007, 06:10 AM   #28
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QuoteOriginally posted by RiceHigh Quote
Manual focusing by eyes with modern DSLRs are not easy <snip>
Your argument should be that AF camera focusing screens should include split screen and microprism elements...

QuoteOriginally posted by RiceHigh Quote
The reports come from many places, not only here. Also, I state clearly in the beginning of my article that it is "regardless of brand"!
...possibly with a secondary argument against autofocus technology in general.

QuoteOriginally posted by RiceHigh Quote
Nonetheless, your mentioned technique of narrowing down the MF range "little by little" is the right thing to do, I think.
(I can't claim the credit - it was mentioned by Izumi Taniguchi on the Pentax Web site.)

Autofocus is a tool, not a solution. Someone who relies on it unquestioningly is either inexperienced or a fool.

Simon

Last edited by Simon; 01-15-2007 at 06:11 AM. Reason: Typo correction
01-15-2007, 07:04 AM   #29
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QuoteOriginally posted by Simon Quote
Your argument should be that AF camera focusing screens should include split screen and microprism elements...
You cannot have a needle which has two pins..

The main mirror is called a half mirror as at least a portion of the light pass thro it and go to the secondary smaller mirror for the AF, say, 30%.

So, the focusing screen cannot as "rough" as that was before and no more ground glass can be used unless the viewfinder is made to be rather dim.

But ground glass is the media for the MF, clear glass focusing screen simply don't do the job as a good aids.

Also, the central "loop hole" of the main mirror will cause unevenness in the viewfinder image. To relieve the syptom, the mirror has to crave for marks for those "totally intransparent" outer side and the density will increase from inward to outside. Well, the ancient Minolta 7000 and the Pentax SFX has this. And, the Pentax SFX has ground glass focusing screen!

The 1.5X crop factor of DSLRs made thing worse as there is less light entering the finder for the same FOV.

QuoteQuote:
...possibly with a secondary argument against autofocus technology in general.
Nope. I'm a big fans of AF. It's convenient and is a joy to use.

(I can't claim the credit - it was mentioned by Izumi Taniguchi on the Pentax Web site.)

QuoteQuote:
Autofocus is a tool, not a solution. Someone who relies on it unquestioningly is either inexperienced or a fool.

Simon
Then, I'm either one of these! But do note that I've experienced no significant problem with my MZ-S, even I used for years my FA*85/1.4 at f/1.4 to f/2.0. Ditto for my K100D used under daylight with my FA*85/1.4 - no problem here!

I'm glad to continue as a fool as long as the AF of my SLR is something that I can rely on.
01-15-2007, 07:15 AM   #30
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QuoteOriginally posted by RiceHigh Quote
The main mirror is called a half mirror as at least a portion of the light pass thro it and go to the secondary smaller mirror for the AF, say, 30%...
You describe some interesting problems seeking solutions. Maybe if you can come up with solutions you will make a lot of money. In the meantime perhaps you should seek a manual focus body or put up with the limitations of the technology.

QuoteOriginally posted by RiceHigh Quote
Nope. I'm a big fans of AF. It's convenient and is a joy to use.
Yet you say that ciriticism of auto-focus accuracy is not manufacturer-specific.

QuoteOriginally posted by RiceHigh Quote
I'm glad to continue as a fool as long as the AF of my SLR is something that I can rely on.
But I doubt that you are. If you can see that your camera has failed to find correct focus (as surely happens in all sorts of marginal situations), do you click anyway and complain about the results? I suspect, like me, you will select a different AF point, use AF lock or (heaven forbid!) take manual control.

Simon
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