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A7r - Unusual memory card event

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jpartlo

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Sorry for the double post, pushed the wrong key.

I'm gradually learning how to use my new A7r. Technique is important and I don't think you can get away with lazy. Last weekend I had a day shooting in a village near me in Suffolk, England. I'm familiar with the place and shot around 250 frames. Once downloaded and processed I was dismayed to find I couldn't get any shot to be truly sharp and to display fine detail. As I say technique is important but even I can't miss every shot with the three lenses I possess - FE35,FE55 and a old Canon 100mm fd. So I wondered was my camera suddenly faulty? Well, as well as the camera being common to all the shots so was the memory card. I did a fairly rigorous test on all six of my cards and sure enough one the the cards produces files with a noticable slight blur and a loss of fine detail. I can't recall ever hearing of such a thing happening to any one else but my gloom has certainly lifted.

Just for fun I attach some other shots that have maybe worked OK.

Regards

jim partlo

































 

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How did you do the tests? I really can't imagine the card being the cause of blur of some kind..
 
Hello - Yes, I couldn't imagine how such a thing is possible but I'm pretty sure it's the case. I tripod mounted my A7r and with each lens I took the same shot with each card using the same settings. I then downloaded the files to my computer and ran them through PS 6 with the same settings on each file and I was suprised to see that one card on every file displayed a slight blurring and the loss of fine detail. It doesn't seem possible but with three different lenses displaying the same effect on the one card I can't argue with what I'm seeing.

Regards

jim partlo
 
Could you post same samples? What cards did you use?

I find this topic very curious. I really wouldn't know how this could technically be explained.
 
jpartlo said:
Hello - Yes, I couldn't imagine how such a thing is possible but I'm pretty sure it's the case. I tripod mounted my A7r and with each lens I took the same shot with each card using the same settings. I then downloaded the files to my computer and ran them through PS 6 with the same settings on each file and I was suprised to see that one card on every file displayed a slight blurring and the loss of fine detail. It doesn't seem possible but with three different lenses displaying the same effect on the one card I can't argue with what I'm seeing.

Regards

jim partlo
Click to expand...
I would say the conclusion so far must be highly unlikely, if not impossible. If a card posseses some fault making the files somehow semi-corrupted, it would show as digital artefacts, not a general blur. For the card the picture files are just sets of numbers a la 00111010101010101001. How a techincal error manages to hit the exact right 0s and 1s so the result shows as a blurred image, must be so improbable that it in practice is impossible. Your experience so far makes you believe the card is the cause, but I would say it is much much more likely the the method and/or conclusion is wrong. However, I don't know what the correct conclusion would be.
 
Gentlemen - I cannot argue against the science which I do understand, however, what I see on my calibrated Nex monitor is another matter. Attached you will find six shots and I believe you will see a modest difference in them. Jpeg compression may make the difference seem to be small but given the physics why is there a difference at all? I prepare my files for printing and given the quality of the sensor and the Sony lenses I expect to see very fine details which I do but not on this particular card. Shots 11 and 13 are from the 35mm, numbers 17 and 19 are from the 55mm and 23 and 25 are from the manual Canon 100mm. The difference in quality between the Canon and the Sony lenses is clear.

Regards

jim partlo

































 
Interesting. I do see the difference you talk about. Still, I have no idea how to explain it.

I guess all you can do is get rid of that card, if that's what causes the problem.
 
Wow, digital is digital. Whatever the camera writes to the card is the photographer's and/or camera's doing, not the card's. Don't blame the card for bad photography. Take a look at your camera, lens, or your skills, because therein lies the issue. The issue is not with the card.
 
So your suggesting that every one of the 250 shots I took last weekend that display this quality was an operator error and that the other 5 cards I used in my test that did not display this fault were just a product of luck and that it just happened that when using the faulty card I got my technique wrong? I mounted my camera on a tripod, fixed a lens and then changed the 6 cards in a series and your suggesting that when it came to card 4 (the faulty one) I managed to get it wrong and I continued to do so with the next lens and the next. Seems an improbable chain of events. My other 5 cards seem to work just fine! I might be wrong but read/write errors are not entirely unheard of in the digital is digital world.

Regards

jim partlo
 
jpartlo said:
So your suggesting that every one of the 250 shots I took last weekend that display this quality was an operator error and that the other 5 cards I used in my test that did not display this fault were just a product of luck and that it just happened that when using the faulty card I got my technique wrong? I mounted my camera on a tripod, fixed a lens and then changed the 6 cards in a series and your suggesting that when it came to card 4 (the faulty one) I managed to get it wrong and I continued to do so with the next lens and the next. Seems an improbable chain of events. My other 5 cards seem to work just fine! I might be wrong but read/write errors are not entirely unheard of in the digital is digital world.

Regards

jim partlo
Click to expand...
We would like to know the cards you are using and the one that is causing problems. Can't you provide this information? Have you tried formatting the card on a computer or checking it for errors?

Who knows, you could be on to something and the compression that is used by a specific storage card maker but do give us more information.
 
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jpartlo said:
So your suggesting that every one of the 250 shots I took last weekend that display this quality was an operator error and that the other 5 cards I used in my test that did not display this fault were just a product of luck and that it just happened that when using the faulty card I got my technique wrong? I mounted my camera on a tripod, fixed a lens and then changed the 6 cards in a series and your suggesting that when it came to card 4 (the faulty one) I managed to get it wrong and I continued to do so with the next lens and the next. Seems an improbable chain of events. My other 5 cards seem to work just fine! I might be wrong but read/write errors are not entirely unheard of in the digital is digital world.
Click to expand...
As I look at the samples, I think I'm seeing motion blur in one vs. the other. I can think of no reason this would be the card's fault.
 
The card in question is an older Lexar Premium Series 32gb sdhc. As to motion blur I'm at a loss how this could happen. I mounted my camera on a tripod, fitted a lens and then shot 3 frames on different cards that were fine, the 4th shot is the bad card and after that I take 2 more frames with different cards and they too are fine. I proceed the same with two more lenses and the 4th card always displays this blurring. It takes a stretch of credibility to suggest that somehow out of 18 shots I always manage to blur exactly on the 4th card in the series. For my part I'll simply bin the card and carry on happily with the others. The mystery will remain.

Regards

jim partlo
 
jpartlo said:
The card in question is an older Lexar Premium Series 32gb sdhc. As to motion blur I'm at a loss how this could happen. I mounted my camera on a tripod, fitted a lens and then shot 3 frames on different cards that were fine, the 4th shot is the bad card and after that I take 2 more frames with different cards and they too are fine. I proceed the same with two more lenses and the 4th card always displays this blurring. It takes a stretch of credibility to suggest that somehow out of 18 shots I always manage to blur exactly on the 4th card in the series. For my part I'll simply bin the card and carry on happily with the others. The mystery will remain.

Regards

jim partlo
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I would be very curious to see if you notice any difference by formatting the card on a computer and then retrying it. Formatting a card in the camera is not a full format which some don't realize. It retains system information and directory structure on the card. There are articles that generically address file deterioration on SD cards and some more specific ones that address file degradation on a hard drive but only after extended periods of time.
 
stevo23 said:
jpartlo said:
So your suggesting that every one of the 250 shots I took last weekend that display this quality was an operator error and that the other 5 cards I used in my test that did not display this fault were just a product of luck and that it just happened that when using the faulty card I got my technique wrong? I mounted my camera on a tripod, fixed a lens and then changed the 6 cards in a series and your suggesting that when it came to card 4 (the faulty one) I managed to get it wrong and I continued to do so with the next lens and the next. Seems an improbable chain of events. My other 5 cards seem to work just fine! I might be wrong but read/write errors are not entirely unheard of in the digital is digital world.
Click to expand...
As I look at the samples, I think I'm seeing motion blur in one vs. the other. I can think of no reason this would be the card's fault.
Click to expand...
There IS motion blur on those shots. Maybe the card moved in its housing during the shot…

;-)
 
PatrickSmith said:
stevo23 said:
jpartlo said:
So your suggesting that every one of the 250 shots I took last weekend that display this quality was an operator error and that the other 5 cards I used in my test that did not display this fault were just a product of luck and that it just happened that when using the faulty card I got my technique wrong? I mounted my camera on a tripod, fixed a lens and then changed the 6 cards in a series and your suggesting that when it came to card 4 (the faulty one) I managed to get it wrong and I continued to do so with the next lens and the next. Seems an improbable chain of events. My other 5 cards seem to work just fine! I might be wrong but read/write errors are not entirely unheard of in the digital is digital world.
Click to expand...
As I look at the samples, I think I'm seeing motion blur in one vs. the other. I can think of no reason this would be the card's fault.
Click to expand...
There IS motion blur on those shots. Maybe the card moved in its housing during the shot…
Click to expand...
That's it! The card is heavier and therefore harder to hand hold.
 
True story: In 2000 I went to Best Buy to purchase my first digital camera. It was a simple point and shoot (Olympus C300Z). The sales guy was helping me pick up a memory card. I was looking at two cards, both the same size but one of them was made by sandisk and was more expensive so I asked the rep about the reason. He picked up the card, looked at the packaging and replied "oh. the pictures this card takes are of a much higher quality than the others."
 
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PVCdroid - I have formatted the card in windows 8 but haven't had the opportunity to trial it yet, perhaps tomorrow.

Regards

jim partlo
 
jpartlo said:
I'm presuming you bought the most expensive one and haven't looked back since.

All the best

jim partlo
Click to expand...
Of course. the pictures were as sharp as a razor, awesome creamy bokeh and a fantastic "3D" feel. all because of the superior card.
 
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