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06-29-2009, 04:21 PM   #16
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QuoteOriginally posted by Marc Sabatella Quote
I'd say, spend some time reading the hundreds of other threads on focus over the years, come to good understanding of how the autofocus system works and the common user errors in using it - most common being failure to adequately control what the camera is actually focusing on. Then download one of the good focus test charts referenced in those other threads, read the isntructions carefully, follow them carefully, test in good light (not incandescent), and post the results.
I get what you are adding, good tip for sure...my issue is not so much with the focus in general but rather the inconsistent focus. Mind I was using a tripod on a static scene and the Pentax K IR remote...I even used MLU a couple times. I tried SR on, SR off and all manner of settings in between as well as resetting all the camera settings to factor fresh. I stopped short of re-flashing 1.03 though...and I tried 'green box' mode also to let the camera do all the work.

But, my results would vary from shot to shot as the samples show, taken within moments from one another with the same settings. And it was ONLY after the "magic cleaning" that the lens settled down and began producing consistent results from shot to shot...

I fully appreciate this focusing system is going to be a bit different from what I am coming from and need some time to understand it's behavior, but it should not be so different or 'high strung' as to produce the widely varying results as I was getting last night/early this AM.

Plus I never discount my own incompetence as a potential source of error...hahaha...that all said, the results are there to look at and, well, not much I can say beyond what has already been written here.

My battery just finished recharging a short bit ago and all shots were spot on as they were after the 'magic cleaning'. So, I really thing there was something on the element affecting the focus in a random fashion depending on how the light was being passed through the lens. Weird that is also happened on the tripod though...and before the idea about turning SR off on the tripod, I experiment with it both ways and received the same results.

Just was a weird one...and anytime in the next hour, I'll have the 35mm limited to use as a comparison...but I do not expect the issue is with the lens build itself. Really looking forward to using the macro though, it will be weird coming from the 180mm macro, I think the perspective will seem more realistic though, but that Sigma 180mm APO as not bad at all.

06-29-2009, 07:03 PM   #17
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just a friendly aside

If you mean multiple personalities, that's schizoid. Schizophrenia is a different thing entirely.

(It's one of those common mistakes that irks me.)

P.S. I am not a psychiatrist nor do I play one on TV.
06-29-2009, 07:11 PM   #18
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QuoteQuote:
If you mean multiple personalities, that's schizoid.

Well I am glad I dont suffer from that

Yes you do

No I dont

Yes you do
06-29-2009, 07:11 PM   #19
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QuoteOriginally posted by rparmar Quote
If you mean multiple personalities, that's schizoid. Schizophrenia is a different thing entirely.

(It's one of those common mistakes that irks me.)

P.S. I am not a psychiatrist nor do I play one on TV.
no, really?

hehehe...good comment, as a lot of folks do not know there is a huge difference. One is actually very rare, the other, not so much really. Even more think such conditions are willful and indicate a person is somehow weak willed and a bad person. Sadly these 50s era "Leave it to Beaver" thought processes are slow to die off. The conditions are no different than any other sort of disease. No cure only palliative care with a bit of cognitive therapy is the best people can to in an effort to hold it at bay or at least slow any progression/collateral complications with their lives in general.

At least with my RA, there are pain meds which work most days...though the meds used to slow the progress down are potentially far worse than the disease itself. Same goes for a large variety of other auto-immune diseases.

06-29-2009, 07:12 PM   #20
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QuoteOriginally posted by nulla Quote
Well I am glad I dont suffer from that

Yes you do

No I dont

Yes you do
06-29-2009, 07:16 PM   #21
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btw, back on topic...I can only say this about the 77mm Ltd...SCREW FIGURING IT OUT...I LOVE this 35mm Macro Ltd!! Holy-Schnikes!! Amazing and just what I had expected from the 77mm...I might just hold off on buying that Sigma 24-60 for a few days now...gotta see if I can coax the 35mm to work as my product lens. I expect there to be little problem on that front...it's freaking amazing!
06-30-2009, 12:52 PM   #22
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QuoteOriginally posted by brecklundin Quote
I get what you are adding, good tip for sure...my issue is not so much with the focus in general but rather the inconsistent focus.
Right, and that's what IO was getting at in suggesting you read about how AF systems work and the issues that come up in trying to use them. It's hard to tell from one posted picture, but my assumption is that the camera simply chose to focus somewhere other than where you wanted. That's normal and only partially avoidable - but the first step would be learning what steps you can take to try to avoid it. Selecting the focus point yourself, for instance, is the place to start, but you also have to be aware that the AF sensors are *MUCH* larger than the little red squares that light up in the viewfinder so even if the red square lights up where you wanted, that is no guarantee the camera will focus on that *exact* spot - all it tells you is that it is somewhere *near* that spot. If there is something bearby that is further in front or further in back, the camera might legimately focus there instead. That's just life with an AF system - they can't always read your mind.

It's also possible, of course, that you are fully aware of all this, but as I said, it was tough to tell from the posted picture and your description. So without further evidence to the contrary, my assumption is simply that the camera chose to focus somewhere other than you intended, and you either didn't do all you could to try to force it to focus where you wanted, or you tried, but the AF sensor is simply too large an object to pinpoint with the necessary level of precision for the subject, so you'd want to switch to manual focus in cases where focus is that critical.

QuoteQuote:
So, I really thing there was something on the element affecting the focus in a random fashion depending on how the light was being passed through the lens.
That's certainly possible, but wouldn't discount what I wrote above. Clean lens or not, there will be times when the camera will not read your mind correctly, and you'll need to learn to do what you can to maximize your chances of success but also to recognize when you won't be able to guarantee success and will be better off focusing manually.
06-30-2009, 12:57 PM   #23
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QuoteOriginally posted by rparmar Quote
If you mean multiple personalities, that's schizoid. Schizophrenia is a different thing entirely.
Actually, while "schizoid" is indeed separate from schizophrenia, neither is the same as multiple personality disorder (MPD), aka dissociative identity disorder (DID).

QuoteQuote:
P.S. I am not a psychiatrist nor do I play one on TV.
Ditto, but I have known someone diagnosed with this condition (MPD).

06-30-2009, 08:00 PM   #24
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QuoteOriginally posted by Marc Sabatella Quote
Right, and that's what IO was getting at in suggesting you read about how AF systems work and the issues that come up in trying to use them. It's hard to tell from one posted picture, but my assumption is that the camera simply chose to focus somewhere other than where you wanted. That's normal and only partially avoidable - but the first step would be learning what steps you can take to try to avoid it. Selecting the focus point yourself, for instance, is the place to start, but you also have to be aware that the AF sensors are *MUCH* larger than the little red squares that light up in the viewfinder so even if the red square lights up where you wanted, that is no guarantee the camera will focus on that *exact* spot - all it tells you is that it is somewhere *near* that spot. If there is something bearby that is further in front or further in back, the camera might legimately focus there instead. That's just life with an AF system - they can't always read your mind.

It's also possible, of course, that you are fully aware of all this, but as I said, it was tough to tell from the posted picture and your description. So without further evidence to the contrary, my assumption is simply that the camera chose to focus somewhere other than you intended, and you either didn't do all you could to try to force it to focus where you wanted, or you tried, but the AF sensor is simply too large an object to pinpoint with the necessary level of precision for the subject, so you'd want to switch to manual focus in cases where focus is that critical.



That's certainly possible, but wouldn't discount what I wrote above. Clean lens or not, there will be times when the camera will not read your mind correctly, and you'll need to learn to do what you can to maximize your chances of success but also to recognize when you won't be able to guarantee success and will be better off focusing manually.
sure mom...what ever you say. But if using spot metering and CP focus is that inconsistent then this system has problems and I won't be using for long. It's that simple. In fact it is a reason to drop it like a stone. Perhaps the K7 will have a functioning AF. I am used to systems where the AF for anything beyond macro is 99% spot on. I suspect one of the issues is the quite slow AF tracking is not great combined with the lack of visable focus points in the viewfinder makes keeping the point on the original target by the time you click the shutter button completely. But I know it's not the AF tracking that is the issue since with tracking off the results were similar.

All I asked was if the lens had a history of focus weirdisms not for a lecture on how I should be using the focus and that I need to accept AF does not work as on every other digital I have ever used.

Sorry if that is curt, but it cuts through the BS and gets to the point. And the point is, I acknowledged your suggestions were vaild and even if I did not gush over them, nowhere did I discount them. As before I appreciate the suggestions but they did not really answer the question asked. And the question is important because if there is a history a fast trip to Pentax for adjustment and checking is simple and easy rather then spending hours traking down a problem from which a $500-$600 bit of gear should suffer. I think it is the coolest looking lens I have ever used...but right now a 20-yr old $30 MF 50mm lens is a better option if the results stay as they are currently.

Oh, btw, since I received the body last week, there have been 1000ish shots taken...not one...nor did I post just one shot, rather 20+ of the same scene in a static controlled environment, had you followed the link you would be aware of that.

For now, I am not thrilled with the lens. Especially compared the the 35mm Macro Limited. Heck, my Sigma 24-60 delivers far better images under similar conditions and I have shot 1000s of shots with that lens. Still I will give it time and see if I can justify not selling it for a better option for me personally.

I LOVE the shots people have posted with the lens, not like a person drops over $500 on a lens to piss all over it...or over $2500 on new gear to do the same thing.

I mentioned earlier in the thread...I would know more once the 35mm arrived. It got here yesterday and is spot on ever shot...this leads to only the 77mm as the issue. Which was my original question, does the lens have a history of strange focus issues.
06-30-2009, 09:57 PM   #25
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QuoteOriginally posted by brecklundin Quote
sure mom...what ever you say.
Is that how you typically respond to people who are trying to provide help?

QuoteQuote:
But if using spot metering and CP focus is that inconsistent then this system has problems and I won't be using for long.
Like I said, it's hard to say from one sample picture. I'm just telling you things that are true of *all* AF systems. It's still unclear to what extent you already knew, or even understand, what I am saying, but at this point, given your attitude, my interest in continuing to help has waned.
07-01-2009, 09:15 AM   #26
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QuoteOriginally posted by Marc Sabatella Quote
Is that how you typically respond to people who are trying to provide help?



Like I said, it's hard to say from one sample picture. I'm just telling you things that are true of *all* AF systems. It's still unclear to what extent you already knew, or even understand, what I am saying, but at this point, given your attitude, my interest in continuing to help has waned.
I think breck is only kidding ! and I do think he appreciates the help that you guys give.
07-01-2009, 03:38 PM   #27
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yeah Marc...I was really JOKING with the first line...that was why the smiley!! I do appreciate your effort to help but was also trying to let ya know I am pretty familiar with the whole issue of AF and such. Yet at the same time I never had a lens/body combo miss it's focus as frequently as this one. I do realize the vast majority of folks complaining about a soft or missed focus are simply not used to the razor thin DOF at f/1.8, heck at f/4 for that matter. That is not the case for me. I would have said that explicitly but, well, that too can come across as kinda stuck-up. So, instead I tried to explain what I have done and that there was a method to the madness hoping those who read it would understand I was not basing it on one hand held low light AF test. Your comment seemed to miss that part and rather focus on your own method. And all I was really after was not someone to fix it for me but rather to let me know if the lens had any history of AF issues which I had not been able to sleuth out myself here on the board.

And as I said, so far the lens is not impressing me but that I also understand there is a learning curve to any bit of gear. Too many are very please with this lens. My primary concern is that the trip from Canookia was just a bit rough as the packing was not great so something might have been knocked off alignment just enough.

So really, no offense was intended, just a bit of ribbing...that's me is all...hope that works for ya!! We are bound to run into each other here so best to make sure we "get" each other.

BTW, for now an AF adjustment of +4 is working well and giving consistently decent test shots at all apertures. Still learning to watch for the purple fringing bug-a-boo but that's just life with this lens, that part I was aware of...

Anyway, hope this all make sense...and thanks 'PP' for trying to help!! I really am enjoying the folks here...
07-01-2009, 04:06 PM   #28
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QuoteOriginally posted by brecklundin Quote
But I almost exclusively use the center FP and in this case I was using it. I tried the two modes for selecting the CFP using SEL or the[*] (specifically set to the CFP only) setting one whatever that dial is called (NOTE: I just looked in the manual and it is called AF Switch Point Switching Dial ---gee who know it would be that simple?...). In fact one of the first things I checked as to be sure I was not letting the danged camera select the FP...for me that never works well. Took me about 2-months with the 40D before I realized it flat was useless on that body...it would miss just enough to look OK on the LCD then during post, I learned I really stunk on ice...now that was the camera setting for sure!

Ah. I like to call that the Built In Subject Suggestor. Don't use it much, either.
07-01-2009, 04:15 PM   #29
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hahahaha...I LIKE that definition. I wonder just how many new to the hobby that 'feature' has turn-off? I honestly was really frustrated with the 40D at first until I realized how it was screwing up the shots.
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