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03-11-2014, 08:58 PM   #16
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This video shows just a strobe light hitting the camera mount at ISO 1600 is all it took on the A7

Sony A7-A7r and Fuji X-T1 have a light leak issue (Both can be solved). | Mirrorless Rumors

Far cry from ISO 25600 and 30 seconds

03-11-2014, 10:54 PM   #17
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QuoteOriginally posted by tuco Quote
This video shows just a strobe light hitting the camera mount at ISO 1600 is all it took on the A7

Sony A7-A7r and Fuji X-T1 have a light leak issue (Both can be solved). | Mirrorless Rumors

Far cry from ISO 25600 and 30 seconds
Sony is promising a firmware fix in the near future. There is a firmware solution for every problem, even light where you don't want it.


Steve

(Just tested my K10D against my guide number 61 strobe at full power and ISO 1600...no leak...)
03-11-2014, 11:28 PM   #18
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QuoteOriginally posted by stevebrot Quote

(Just tested my K10D against my guide number 61 strobe at full power and ISO 1600...no leak...)
Shine the strobe at the vf instead.

I am unable to reproduce this light leak problem with my A7r and any FE lens attached. Only when I attach the body cap or off brand lens the problem with the purple streaks, exactly like the ones earlier in this thread, start to appear.
03-12-2014, 12:49 AM   #19
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Or better, drill a hole as I previously suggested

Imaging Resource, again on light leaks:
Sony A7 light leak, round II of III - Results of direct-sun test suggest more testing needed…
"The Pentax K-3 and K-5 were entirely lightfast."
I'm surprised about the D800.

By the way, they managed to find a real-world application where it can have an impact. It wasn't easy, though

03-12-2014, 05:01 AM   #20
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QuoteQuote:
And for you Fanboys who just can’t wait to Sony bash over this odd little issue, let he whose camera is without light leak cast the first stone. Because, so far the same problem has been found with Canon, Nikon, and Fuji cameras. I assume a similar solution will work just fine for those, too.
LensRentals.com - The Sky is Falling and the Light is Leaking: the A7r Anti-Massacree
03-12-2014, 05:25 AM - 1 Like   #21
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Conventional definition of a fanboy ("fanboi" to the terminally cool):
Someone who uncritically admires a product or person, without understanding it or them.
Alternative definitions:
1. Someone who denies the greatness of something I uncritically admire, and chooses something else; or
2. Someone who has the temerity to prefer something I don't understand, and therefore despise.
03-12-2014, 05:59 AM   #22
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My two-steps approach regarding such issues:
+ is it serious?
- so-so. It's not something that shows up only at "30 seconds at ISO25600" but it needs special conditions to appear.
+ is there a workaround?
- Yes! Black tape, cheap and efficient - and only needed in those rare cases where the leaks might show up in your pictures.
No need to panic, then.

I would not consider the camera weather resistant, by the way; and Sony retracted such claims from their site. Many good cameras are not weather sealed (and I will remind again that the Sony is cheaper while still extremely capable)
I would be more concerned about the "squishy mount", but I only know about one such case - most likely a defective sample. Just to keep in mind this isn't a camera to support a medium (or larger) lens.

But sure, it's nice to know the insanely hyped Sony, the camera-that-would-solve-all-Pentaxians-problems, is not perfect

03-12-2014, 06:41 AM   #23
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QuoteOriginally posted by Kunzite Quote
...But sure, it's nice to know the insanely hyped Sony, the camera-that-would-solve-all-Pentaxians-problems, is not perfect
But it does exist. :-)
03-12-2014, 10:21 AM   #24
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QuoteOriginally posted by Kunzite Quote
- Yes! Black tape, cheap and efficient -
Yep, black tape is just the thing. Sony should include a roll and/or a couple of hair-ties as accessories in the box.


Steve

(...still scratching head that a $2300 USD camera should fail at something as fundamental as being light-tight at the mount face with the manufacturer's lens mounted...)

---------- Post added 03-12-14 at 10:28 AM ----------

QuoteOriginally posted by Clavius Quote
Shine the strobe at the vf instead.
Very good, though that is where my eye usually is and doing so sounds painful

Seriously though. I have been VERY intrigued by the a7 and a7R and have a couple of online friends that are doing very good work with their cameras. That being said, I noticed that recent photos from one such friend taken at a tropical location (v. bright sun) seem to have evidence of extraneous light or flare and I wonder if a light leak might be the problem.


Steve
03-12-2014, 11:08 AM   #25
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QuoteOriginally posted by stevebrot Quote

(...still scratching head that a $2300 USD camera should fail at something as fundamental as being light-tight at the mount face with the manufacturer's lens mounted...)

Steve
i can see you having a heart attack at the thought of a $7,000 camera that leaks light at the lens mount

"BUT when I read about Leica's new flagship, the Leica M 240, here on the forum, I have to say I am a bit surprised. A camera in this price range should obviously be flawless and should not leak light between the lens and camera body (Leica User Forum - Das weltweit größte Leica Forum) and threre should not be parts become loose inside the camera (Leica User Forum - Das weltweit größte Leica Forum). And it should not take several weeks for Leica to solve these embarrassing faults."
Should I reconsider? - Leica User Forum
03-12-2014, 01:34 PM   #26
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QuoteOriginally posted by stevebrot Quote
Very good, though that is where my eye usually is and doing so sounds painful
Also with 30 seconds exposures at ISO256000?
03-12-2014, 02:08 PM   #27
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Putting all personal preferences and jokes to one side, are we really surprised by this failure (and, in strict technical terms, it is a failure of sorts) or by the reports of defects in more expensive cameras? We seem to be obsessed with the image that (particularly) Japanese and German manufacturers have enjoyed (and promoted, if not fabricated) for some time, in that they are immune from defects, or, to the better informed, making products that fall within extremely narrow tolerances. It's nearly sixty years since Deming introduced the concepts of Quality Management to Japanese manufacturers, as part of their industry re-building after their disastrous intervention in WW2. Since then, we've had variations and extensions on those simple precepts to the point where people tout systems like 'Six Sigma' production with no real understanding of the basic processes they're applied to. While the overall outcome has been that many, if not most, manufactured goods are produced with comparatively little waste and rejects or defects, only 100% inspection can guarantee that all of those goods fall within the design tolerances set in their specifications. Only high value items like Leicas can fall within that inspection regime, and clearly, either they don't do it or error will still creep in, in spite of it.
From the evidence produced for the Sony A7s, it seems their tolerances for body and lenses mount dimensions allow the axes of the two components to be sufficiently eccentric to allow light to enter one corner under particular circumstances. No one here knows whether or not that means their manufacturing tolerances were too wide, or their manufacturing processes were too poorly controlled to prevent it. All of that, it seems to me, is objective truth. Whether or not it's a problem to the user, or a symptom of inadequate manufacturing control, is for the respective parties to judge for themselves.
03-12-2014, 03:30 PM   #28
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Light leaks were very common in the days of film cameras - we used to measure them by the number of weeks one could safely leave film in the camera.

Till recently, digital cameras probably weren't sensitive enough to capture light leaks. With advances in sensor performance, it's hardly surprising they are now being reported on the higher end models of various brands (Canon, Nikon, Sony, Leica, Fuji) under extreme conditions.

Storm in a teacup.
03-12-2014, 05:59 PM   #29
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QuoteOriginally posted by Christine Tham Quote
Light leaks were very common in the days of film cameras - we used to measure them by the number of weeks one could safely leave film in the camera.
Perhaps with your film cameras.

I have owned several over the last 45 years and currently own about a dozen film bodies and have never had film fogged due to light leaks except for my FED-2 and with the FED-2 it happens at exposure time from a point near the rangefinder window and then only from full sun late in the day from the upper right quandrant. I suspect that the reason the FED leaks light is that it is descended from cameras that were Leica copies.


Steve

(...light leak through the lens mount flange? Give me a break. It would be a crime on a K-500 at discount. The price of the a7R (or Leica) merely adds injury to insult...)

Last edited by stevebrot; 03-12-2014 at 06:28 PM.
03-12-2014, 06:41 PM   #30
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Folding bellows cameras would sometimes leak light through cracks in the bellows and, of course many older cameras had the orange window for the frame markers that introduced light into the backs of those cameras. I've left film in my older Pentax screw mount bodies for much longer than a few weeks and never experienced a light leakage problem, even with 400ASA film. Of course, we used to push process HP-5 to 3200 occasionally, but never to 25,600, so those limits were untried.

Still, with 6 stops from 400 to 25,600, 30 seconds at 25,600 becomes 1,920 seconds which is considerably less than an hour of daylight, ignoring the effects of reciprocity failure on the film. So, leaving a 400ASA film in a camera exposed to daylight for a week should more than test its equivalence to this situation. Obviously, we're not talking about the light-tightness of the lens mount alone.
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