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        Important news regarding memory cards and Aiptek SD cameras.

#1 RMihara Jul 30, 2003 07:42 PM

Important news regarding memory cards and Aiptek SD cameras.
 
Hi All,

Taking a short break from work and called up Aiptek to troubleshoot a clients camera problem and found out that they do not recommend using any memory card(s) from PNY.

It seems that Aiptek has received numerous 'problem' calls from users having difficulty with their cameras normal operation with one of these memory cards installed.

Now they are one of the cheapest SD cards out there but for the price... :(

Just thought I'd pass along the info.

Oh btw, it turns out that you can reformat an SD card while it's still in the SD PenCam. Simply hold down the 'Mode' button (only) for 5-10 seconds. The cameras display will show 'FOR' then you push the shutter button and let the camera go through it's gyrations.

In some instances this will help cameras that fault when accessing an SD card.

Regards,
Roger

#2 Joe Bennett Jul 30, 2003 08:52 PM

Roger,

You are the man. I don't think that the word on memory cards would have gotten out as easily if you had not inquired yourself. Thanks alot, as I plan on acquiring an SD in the future (still preparing to part with my mini soon for modification, but finding it hard to send it.......). I plan on using the SD in my Phoenix glider as I like the horizontal orientation as opposed to the mini. Again, thanks Roger..................

Joe :)

#3 Flybyguy Jul 31, 2003 03:11 AM

Yes,

Thanks for passing that along!

Brian

BTW Roger- The pencam still has not been mounted to the Stick, but it will see some action at the Drag Races in Sonoma on Saturday!

Will post some pics (aerial, of course) once I get the cam mounted.

#4 BEC Jul 31, 2003 02:05 PM

Well, I have a 128 Mb PNY card in my Pencam SD and at least so far it's been just fine. And you know, Roger, what that camera's been through :eek:. I wonder what it is about PNY cards that Aiptek has problems with?

#5 Karl Bē Jul 31, 2003 02:20 PM

For computer system memory, I think it used to be that PNY was a discount seller, packaging various makes of ICs under the same part numbers. Most memory could be set slightly higher than the rated speeds, while PNY had less of a margin. This may have all changed in the years since I built my last desktop system, and of course flash memory isn't the same as SDRAM.

I'm using Lexar brand for my Compact Flash ground-bound camera, and a SanDisk SD for my Pencam, both with no problems.

Karl

#6 Extremeone Jul 31, 2003 03:43 PM

SD cards
 
Hi Roger,
I have been using PNY in my SD all along and now have it in the Casio Exilim, I have had no problems. After reading your post I went outside and took the same three pictures with the same camera only using three different SD cards. I have never run a comparison like that before. Of the three I found the Panasonic and PNY were vurtually identical and SanDisk was the worst. I always thought SanDisk was the Rolls Royce of memory cards but this test changed my opinion. The other two came out looking identical but the Sandisk was more harsh and had much less vibrant colors.

For now I will continue to use PNY. I don't doubt for a moment that they told you that but they may have had a bad card or perhaps were looking for a handy excuse. I would say run your own tests and act accordingly.
Regards, John

#7 RMihara Jul 31, 2003 04:24 PM

It may very well be that the memory card problem calls Aiptek receives -or more specifically, the applications engineer I spoke with - comes from PNY card users. I did think about whether this problem would exist with any other memory card manufacturer but I did not think of it before I ended my call so I'll save the question for the next time I contact Aiptek.

Wow John, you brought forth some really interesting news there. I would never have thought about differences between memory cards and how they could affect image quality.

Memory circuits - much like any other electronic component - have variances in their electrical properties from die to die and lot to lot so even obtaining one data point may not be enough ascertain whether one memory card is optimum over another.

It does suggest that perhaps the primary differences between all of the inexpensive Digi-Cams and their image quality are also affected by system memory and not just the imager itself.

[This part is kinda long-winded]
Keep in mind that we are talking of a device that stores logic bit values and not an analog voltage that spans some range. As long as a bit's 'Logic High' or 'Logic Low' falls within specific parameters it is considered to be in that state. So the difference in image quality has to be caused by the imaging processor itself.

The conversion from an 'analog' value (from the CCD or CMOS array) is converted to a digital representation and if the reference for that conversion varies then so does the converted bitstreams values.

The only way the reference voltage could vary is by the main power supply rail. Now keep in mind the variance in electrical properties of one device vs. another and you may have Flash RAM chips that 'sink' more or less current than another comparable device. This in itself could be causing the supply rail to vary thus directly affecting the processors ability to convert analog data into a digital bitstream (worst case scenario here).

I could be entirely wrong here but based on my past experience in data acquisition that would be my first guess.

Anyone else out there with different SD cards care to add to Johns observation?

Roger

Edit: changed 'video processor' to 'imaging processor'.

#8 Extremeone Jul 31, 2003 07:42 PM

Technical Stuff
 
Roger,
What you mean, from and engineering point of view, is that these memory cards are like a box of chocolates. "You never know what you're going to get".
Regards, John

#9 propfan Jul 31, 2003 08:30 PM

Not exactly...
Basically by the time the image gets to the card it's too late for there to be any effect on the image quality. However, the card could possibly cause a slight amount of electrical interference to the part of the camera that grabs the image from the sensor. Then magic high-frequency stuff happens and the camera gets all confused :confused:

I wonder what effect the speed of the card has? It probably grabs the entire image before it starts sending it (otherwise you would have an extremely ugly picture if anything was moving), but maybe the PNY cards are a little slower, and the camera is a little sloppy about checking to see if the card is ready for more data.

#10 Extremeone Jul 31, 2003 09:08 PM

Image grabber
 
I don't think it grabs it all at once. If anything moves we do get an extremely ugly image. At least we do with a CMOS imager, It's called the Jaggies. I hope the CCD imagers will be better. I should find out starting tommorrow.
John

#11 propfan Aug 01, 2003 12:34 AM

Well, it doesn't grab it all at once, but I don't think it would pause to write to FLASH. Writing to FLASH is pretty slow.


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