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02-22-2010, 10:46 AM   #16
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QuoteOriginally posted by er1kksen Quote
Actually, I have not. It's been requested that I test the SR both before and after that firmware update, so since I haven't gotten around to doing that testing yet, I have not yet updated the firmware. It's really become a non-issue for my normal use so I'm not terribly motivated to see about fixing it.
ha-ha! - there you go, wrong of me to ass-u-me
(which makes an "ass"- (out of) -"U" (and) -"me" )

Is there any reason why you would not want to update your firmware -
and see if the issue does go away for you?

02-22-2010, 11:32 AM   #17
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er1kksen I'm sincerely sorry if I offended you. I did not intend that. You were not the originator of this 'mirror slap' issue, but someone who has, fruitfully, taken it up and identified where there might be some concern (having little in fact to do with the physical issue of "slapping"). I hoped my 'idiot' comment was clearly aimed at the original source of complaint, the one who left it with this unfortunate naming. Sorry it came off wrong. The OP in this thread, and many others I'm sure, continue to be misled by the tag "mirror slap" here.

Would someone answer my question?

Is there anything at all hardware related going on here? And if not, can we stop calling it "mirror slap" for god's sake?

Last edited by frascati; 02-22-2010 at 11:40 AM.
02-22-2010, 01:07 PM   #18
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QuoteOriginally posted by UnknownVT Quote
ha-ha! - there you go, wrong of me to ass-u-me
(which makes an "ass"- (out of) -"U" (and) -"me" )

Is there any reason why you would not want to update your firmware -
and see if the issue does go away for you?
Eh, it was a reasonable enough assumption, no harm done.

I do intend to update the firmware, just not until after I've done the initial formal testing, which I keep putting off in favor of other activities (like taking real pictures ).

QuoteOriginally posted by frascati Quote
er1kksen I'm sincerely sorry if I offended you. I did not intend that. You were not the originator of this 'mirror slap' issue, but someone who has, fruitfully, taken it up and identified where there might be some concern (having little in fact to do with the physical issue of "slapping"). I hoped my 'idiot' comment was clearly aimed at the original source of complaint, the one who left it with this unfortunate naming. Sorry it came off wrong. The OP in this thread, and many others I'm sure, continue to be misled by the tag "mirror slap" here.

Would someone answer my question?

Is there anything at all hardware related going on here? And if not, can we stop calling it "mirror slap" for god's sake?
No offense was taken, I did understand that you were referring to whoever it was over at the DPR forums who originally started making a big deal about the "mirror slap problem." I just feel that it's generally a better tactic to maintain some level of politeness when dealing with people, even when their conduct doesn't suggest that they "deserve" it, including the individual mentioned. Calling people idiots doesn't help anybody get anywhere, really.

As far as the nature of the issue, I'm really not sure. I know the what but not necessarily the why. Since the problem has survived one firmware update already (which should have eliminated the problem if it were simply a bug in the original firmware of my specific K-x), other possibilities I've been considering are that the SR hardware is slightly miscalibrated in some K-xs or even that some copies of the 18-55 L are flawed and give the camera incorrect focal length info, leading to overcompensation. I have a friend with a K20D and the II version of the kit lens, as well as several manual lenses of my own, so I intend to test a variety of different combinations to get to the bottom of the issue.

So again, my inclination is to suspect a hardware fault, but one can never really be sure...
02-22-2010, 01:27 PM   #19
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This is perhaps a newbie question, but is this "mirror slap" issue a manufacturing defect that comes with the camera out of the box, or could it also onset after a certain amount of issue of the camera?

I guess what I'm trying to ask is, if the camera doesn't have "mirror slap" to begin with, is it possible for it to degrade over usage?

Thanks

02-22-2010, 02:11 PM   #20
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QuoteOriginally posted by frascati Quote
Is there anything at all hardware related going on here? And if not, can we stop calling it "mirror slap" for god's sake?
There definitely is something going on but I don't think it's likely related only to the reflex mirror shock (happy?), I think it's possibly to do with timing between the shutter/mirror and SR assembly, I suspect that the SR is still settling when the shutter opens.
02-22-2010, 02:19 PM   #21
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QuoteOriginally posted by asdfTT123 Quote
This is perhaps a newbie question, but is this "mirror slap" issue a manufacturing defect that comes with the camera out of the box, or could it also onset after a certain amount of issue of the camera?

I guess what I'm trying to ask is, if the camera doesn't have "mirror slap" to begin with, is it possible for it to degrade over usage?

Thanks
I noted the issue as soon as I started putting the camera through its paces. It's seen a lot of additional wear and tear since I first noticed the problem, but the problem has not changed or worsened, so I don't think any sort of usage-related deterioration is at play.
02-22-2010, 03:15 PM   #22
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I recommend anyone interested in the issue of mirror slap, SR etc read the following thread, and the excellent research paper associated with it:

A study of the effectiveness of K7 shake reduction: Pentax SLR Talk Forum: Digital Photography Review

Research paper:
Study of the Effectiveness of Shake Reduction in the Pentax K7

This is how these sort of issues should ideally be investigated...

The conclusions dispute the contribution of SR and mirror slap resonance in the K-7 to image blur. I suspect the same would apply to the K-x.
02-22-2010, 06:24 PM   #23
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QuoteOriginally posted by rawr Quote
I recommend anyone interested in the issue of mirror slap, SR etc read the following thread, and the excellent research paper associated with it:
....
The conclusions dispute the contribution of SR and mirror slap resonance in the K-7 to image blur. I suspect the same would apply to the K-x.
Thanks for reference! That is a very good test, and a really excellent writeup.

It clearly shows the benefits of K7 SR extend far beyond a single stop. It also shows that this particular K7definitely does not have the SR/mirror problem at 1/80s.

The test also showed a big difference between horizontal and vertical handheld positions. Interesting that vertical is much worse.

The test also shows the general mirror slap affect. The rigid bench test with MLU is noticeably less blurry than without MLU. Not a big effect, but noticeable. He tested with a 50mm, and a longer FL would probably show a bigger effect. This is not surprising, and absolutely not a defect. Almost any DSLR or SLR will show an effect from mirror slap. That is exactly why better cameras have MLU. (one reason I won't buy a Nikon below the D90, they don't offer MLU)

I would expect the Kx to have a bigger mirror slap effect. Not a defect, but the shutter release is much louder than average, and the tested model, the K7, has a very quiet shutter.

03-02-2010, 03:53 AM   #24
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I got a bunch of blurry DA40 pics last week at around 1/100s. Here's crop of one, the netting is not double threaded by the way. Hmmm. Hopefully it's my technique, I'll take more this weekend to see.
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03-02-2010, 07:52 AM   #25
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QuoteOriginally posted by twitch Quote
I got a bunch of blurry DA40 pics last week at around 1/100s. Here's crop of one, the netting is not double threaded by the way. Hmmm. Hopefully it's my technique, I'll take more this weekend to see.
That looks like the "double image at 1/80s - 1/120s" problem that a few others have seen. (Some people don't like calling it a mirror slap problem.)

When you test it, try with and without SR. Some cameras have no problem unless SR is on. Others have a "blurriness" at those speeds with and without SR.

Good luck
03-02-2010, 04:33 PM   #26
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I’ve spent a little time looking at the exif data of a hand full of my favourite photos. Turns out some of my favourites are also shot handheld at 1/100sec @ ~40mm but with no evidence of ghosting whatsoever, they are tack sharp. Difference is they were taken with my Sigma 17-70 as I’ve only owned the DA40 for a week. That makes it seem more likely a technique issue than a camera issue I think. Maybe because the DA40 is so much smaller and lighter than the 17-70, my technique relies on a heavier lens to grab onto to eliminate shake.

I would have expected camera movement during the shutter press would have more of a “smear” effect rather than the ghosting that can be seen in the crop I posted though. Am I wrong?
03-02-2010, 04:48 PM   #27
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QuoteOriginally posted by twitch Quote
I would have expected camera movement during the shutter press would have more of a “smear” effect rather than the ghosting that can be seen in the crop I posted though. Am I wrong?
I think that's correct, it would likely smear due to an overzealous shutter press, this well defined double image that seems prevalent in example shots is likely camera induced.
03-03-2010, 12:12 AM   #28
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I've just shot 10 test shots of the same scene trying to hold steady as possible, all 1/100sec @ 40mm. 5 with SR on, 5 with SR off.

The results were:
5 out of 5 sharp & no ghosting with SR on
3 out of 5 sharp & no ghosting with SR off, 2 with slight ghosting

So it really does seem I have shakey hands, and in my shots on the weekend I was even more shakey than usual. Yay, seems I don't have the "mirror slap" issue after all.
03-03-2010, 07:19 AM   #29
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QuoteOriginally posted by twitch Quote
I've just shot 10 test shots of the same scene trying to hold steady as possible, all 1/100sec @ 40mm. 5 with SR on, 5 with SR off.

The results were:
5 out of 5 sharp & no ghosting with SR on
3 out of 5 sharp & no ghosting with SR off, 2 with slight ghosting

So it really does seem I have shakey hands, and in my shots on the weekend I was even more shakey than usual. Yay, seems I don't have the "mirror slap" issue after all.
is that why they call you Twitch?

10-29-2010, 07:25 AM   #30
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I did following test ... will post cropped pictures soon, however please let me know if the testing process was right
1) SR on , TV mode - Shutter Speeds 1/30 to 1/200 at 55 MM - No Blurring / double images - Horizontal camera position
2) SR on , TV mode - Shutter Speeds 1/30 to 1/200 at 55 MM - No Blurring / double images - Vertical camera position

As I took the shots indoors ISO was set to 3200, so I can see slight noise at 100% crop due to high ISO, the picture I took was of a Moisturizer bottle and had a lot of text written over it, I think it is easy to spot blurring on text rather than on anything else.

I did not find any blurring or double text on pictures at 100% crop... so I think atleast my camera does not have this issue.

Please let me know your thoughts or any other tests that I need to do...

Thanks.
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