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Interesting Incorrect Shutter Count Finding

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NIKO View Drop Down
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Post Options Post Options   Quote NIKO Quote  Post ReplyReply Direct Link To This Post Topic: Interesting Incorrect Shutter Count Finding
    Posted: 08 April 2021 at 14:46
Hello all. I tried some shutter count tools found online to gauge what my A77II camera has in terms of actual camera count. For starters let me simply say I know that I have less than 6000 shots made on my camera since its purchase back in November of 2014. I haven't used it all that much since I also have 2 A700's and a Maxxum 5D which I continue to use.

Anyway, when I used a few of the counter tools available online they show my camera having a shutter count in the 9000's and not in the 5000's. I found that very odd. I don't recall ever resetting the counter. However, things get even stranger. Pictures that are only one count from one another according to file name, DSC05459 to DSC05460 to DSC05461 to DSC05462, the shutter count from these counter tools would give me numbers such as 9388, 9390, 9392 and 9394. WTF???

Now maybe, just maybe, I could believe that I accidentally reset the counter. Or perhaps after the camera was built many photos where made at Sony for testing purposes before the camera was sent out for sale. However, why would each file with a file number that is one digit apart show shutter count numbers that are 2 digits apart? I fail to understand.

Has anyone encountered this phenomenon? Any ideas as to why this is?
A77II|2xA700|5D|2xMaxxum7|CZ1680|1635|2470|S28|50|24105|70200G|1.4X&2XTC|2xF60M|4xF56AM|M50|2885|28135|3570|70210|KM1870|1735|2875|2x3600HSD|Σ10|70|85|1020|100300|1.4X&2XTC
 



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pegelli View Drop Down
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Post Options Post Options   Quote pegelli Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 14:56
Maybe (just a theory):
EFCS on: 1 shutter count per photo
EFCS off: 2 shutter counts per shutter

But I know for a fact that for instance sweep panoramas on my NEX6 and A6000 count all the shutter clicks for just 1 file (and 1 file number), the same happens with in camera HDR and other multi-frame captures (like ISO-AUTO), all shutter clicks get added for just one file number.
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Post Options Post Options   Quote QuietOC Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 14:58
Yes, I think using both mechanical curtains counts each one separately. You would need to enable the electronic front curtain to limit the shutter count to one per picture.

Several Sony cameras only have a single mechanical curtain including the recent A7C.

Edited by QuietOC - 08 April 2021 at 15:01
Sony A7RIV NEX-5T HVL-F45RM LA-EA3 LA-EA4r MB-IV MC-11 EF-E II TLT ROKR MD-NEX KR-NEX DA-NEX
Minolta Maxxum 600si
Pentax Q7 5-15 15-45/2.8 8.5/1.9 11.5/9 AF-P/Q
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Post Options Post Options   Quote NIKO Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 15:30
Originally posted by pegelli pegelli wrote:

Maybe (just a theory):
EFCS on: 1 shutter count per photo
EFCS off: 2 shutter counts per shutter

Yes..... I have my EFCS set to "Off."

Originally posted by QuietOC QuietOC wrote:

Yes, I think using both mechanical curtains counts each one separately. You would need to enable the electronic front curtain to limit the shutter count to one per picture.

Wow..... That's interesting. I truly didn't know that the A77II had 2 mechanical curtains. Why would that be? What is their configuration?

Does my Maxxum 5D and A700's have 2 mechanical curtains or only one? I've been using them for years and now I'm learning all of his???
A77II|2xA700|5D|2xMaxxum7|CZ1680|1635|2470|S28|50|24105|70200G|1.4X&2XTC|2xF60M|4xF56AM|M50|2885|28135|3570|70210|KM1870|1735|2875|2x3600HSD|Σ10|70|85|1020|100300|1.4X&2XTC
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Post Options Post Options   Quote QuietOC Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 15:48
Originally posted by NIKO NIKO wrote:


Originally posted by QuietOC QuietOC wrote:

Yes, I think using both mechanical curtains counts each one separately. You would need to enable the electronic front curtain to limit the shutter count to one per picture.

Wow..... That's interesting. I truly didn't know that the A77II had 2 mechanical curtains. Why would that be? What is their configuration?

Does my Maxxum 5D and A700's have 2 mechanical curtains or only one? I've been using them for years and now I'm learning all of his???

The electronic front curtain is a fairly recent feature. If the database here is correct, the A77/A65 were the first A-mount bodies with it. People complained about shutter shock with the original A7R because it lacked electronic first curtain and the mechanical first curtain would shake the camera enough to blur images at some shutter speeds.

The 5D and A700 do not have electronic front curtain and always use 2 mechanical curtains. Film cameras also all have 2 mechanical curtains unless they use a leaf shutter or something similar. There are some digital cameras without any mechanical focal plane shutter like my Pentax Q7.

Edited by QuietOC - 08 April 2021 at 15:54
Sony A7RIV NEX-5T HVL-F45RM LA-EA3 LA-EA4r MB-IV MC-11 EF-E II TLT ROKR MD-NEX KR-NEX DA-NEX
Minolta Maxxum 600si
Pentax Q7 5-15 15-45/2.8 8.5/1.9 11.5/9 AF-P/Q
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Post Options Post Options   Quote sybersitizen Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 15:53
Originally posted by NIKO NIKO wrote:

I truly didn't know that the A77II had 2 mechanical curtains. Why would that be? What is their configuration?

Every camera with a focal plane shutter needs two curtains in order to support a range of useful shutter speeds: one to start the exposure and one to stop it.

A single curtain would only work satisfactorily for very slow speeds.

They can be mechanical or electronic, or one of each, but two are required.

Does my Maxxum 5D and A700's have 2 mechanical curtains or only one?

They have two.
 



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Post Options Post Options   Quote sybersitizen Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 16:20
Oh, one other thing. There are reasons for having an option of using mechanical or electronic curtains, as many cameras now offer. Currently, mechanical curtains can support a shorter transit time, providing faster x-sync speeds and better control of skew with moving subjects. Also, mixing a mechanical curtain with an electronic one can cause issues under some circumstances because the two curtains are not in the same physical plane.
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Post Options Post Options   Quote NIKO Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 18:05
Thanks all for the information. Most interesting.
A77II|2xA700|5D|2xMaxxum7|CZ1680|1635|2470|S28|50|24105|70200G|1.4X&2XTC|2xF60M|4xF56AM|M50|2885|28135|3570|70210|KM1870|1735|2875|2x3600HSD|Σ10|70|85|1020|100300|1.4X&2XTC
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Post Options Post Options   Quote amrep Quote  Post ReplyReply Direct Link To This Post Posted: 08 April 2021 at 18:14
For the most used shutter speeds the shutter opening is a moving slit between the two shutter curtains (true for all typical focal plane shutters). But special for a camera with an electronic viewfinder (EVF) that reads out the image from the main sensor is that it obviously also needs to additionally open the shutter fully between exposures. That's why your camera has correctly counted twice.

(In the simplified comparison below "e1" means the EFCS.)

SLR with OVF: open-1 -> expose picture -> close-2 (and stay closed) = 1 mechanical shutter cycle per picture

SLT with EVF and EFCS on: open-e1 -> expose picture -> close-2 -> open-2 (and stay open)   = 1 mechanical shutter cycle per picture

SLT with EVF and EFCS off: close-2 -> open-1 -> expose picture -> close-2 -> open-2 (and stay open) = 2 mechanical shutter cycles per picture

Sony got it right about the shutter counter. You wear out the shutter twice as fast with EFCS off. (Maybe not a problem if you don't use your camera that much.)

Edited by amrep - 08 April 2021 at 18:22
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Post Options Post Options   Quote NIKO Quote  Post ReplyReply Direct Link To This Post Posted: 09 April 2021 at 19:37
Originally posted by amrep amrep wrote:

For the most used shutter speeds the shutter opening is a moving slit between the two shutter curtains (true for all typical focal plane shutters). But special for a camera with an electronic viewfinder (EVF) that reads out the image from the main sensor is that it obviously also needs to additionally open the shutter fully between exposures. That's why your camera has correctly counted twice.

(In the simplified comparison below "e1" means the EFCS.)

SLR with OVF: open-1 -> expose picture -> close-2 (and stay closed) = 1 mechanical shutter cycle per picture

SLT with EVF and EFCS on: open-e1 -> expose picture -> close-2 -> open-2 (and stay open)   = 1 mechanical shutter cycle per picture

SLT with EVF and EFCS off: close-2 -> open-1 -> expose picture -> close-2 -> open-2 (and stay open) = 2 mechanical shutter cycles per picture

Sony got it right about the shutter counter. You wear out the shutter twice as fast with EFCS off. (Maybe not a problem if you don't use your camera that much.)


The best explanation yet. Great description as to what's happening in the camera.

Thanks!!
A77II|2xA700|5D|2xMaxxum7|CZ1680|1635|2470|S28|50|24105|70200G|1.4X&2XTC|2xF60M|4xF56AM|M50|2885|28135|3570|70210|KM1870|1735|2875|2x3600HSD|Σ10|70|85|1020|100300|1.4X&2XTC
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