Steve's Digicams Forums

Steve's Digicams Forums (
-   Memory Cards, Microdrives, Card Readers (
-   -   Lexar Capacity (

mslan May 17, 2004 8:51 AM

I bought a Optio S40 this week and a 256 Lexar 32x SD card. I was surprised when I put the card in on camera (on best resolution) that it said it only had room for 98 pictures. I thought it was supposed to get 128. Was I wrong?

Also how much different is the quality if I move it one down as I am going away an a two week holiday and do want as much storage as possible because I don't know when I will be able to download. I don't blow up more than 8 x 10 (unless there is a spectacular shot!).


eric s May 17, 2004 9:57 AM

I know nothing about that camera. The only S40 I know is the Canon Powershot. Is this the same camera but with a different name?

If not, how many mega-pixels is the sensor on this camera? From the numbers you have stated, the camera is around 3MP. Is that correct?

Since JPG pictures are compressed, the actual number of pictures that can fit on a card is only a guess. The camera can not know how large a JPG picture is until you actually take it.


mslan May 17, 2004 11:13 AM

the Pentax Optio S40 is a 4 megapixel camera with the following resolutions:

2304x1728, 2048x1536, 1600x1200, 1024x768, 640x480

eric s May 17, 2004 3:12 PM

Ah, yes. There it is in the list of reviews Steve did.

That is not that surprising for a number of pictures. That assumes about 1/3 compression of the image. The reality is that some pictures will compress more, some less (for example, blue sky with few clouds compresses lots.) This is why the number of pictures remaining is just a guess.

You would only get 128 images if you got 50% compression on the jpg. Maybe you will.


ps. All my numbers assume you're using the highest quality jpg settings.

mslan May 17, 2004 4:42 PM

So in other words, I would expect the same results with any card and this is not an issue merely on this card that I bought, is that correct?

Puck M May 17, 2004 10:32 PM

In Steve's review of your camera it was stated that4 of highest resolution and least compressed pictures would fit in its 10MB internal memory. That's about 2.5 MB per picture. If that's the case then about 100 pictures would fit on a 256 MB card. Where did you get the 128 number?I have a 256 MB Lexaras well as a 256 MB Panasonic cardand they bothare estimated to hold 156 picturesby my 3 MP camera. I don't think there is anything wrong with your Lexar card. As was previously stated, the number shown by your camera is only an estimate because .jpg picture files can vary in size depending on their content. Your solution to storingmore picturesis to go to less resolution and/or higher compression or better yet, get an additionalcard. Your camera has 5 different resolutions and 3 choices of compression so you should be able to drop back to an acceptable limit.I'm not sure whether less resolution or higher compression would be better. I'll leave that one to the experts.

mslan May 18, 2004 4:43 PM

Here is a chart right from Lexar's site and I think Sandisk uses the same capacity numbers.

So does anyone have a suggestion of compression vs. resolution & which is the lesser of two evils to compromise.

Puck M May 18, 2004 8:36 PM

I see where you got the 128 now. Lexar justused an average number. The fact is that not all 4 MP cameras use the same compression ratio.Since your camera makes bigger filesthey are compressed less which, other things being equal, is good.

For example, I have two 3.2 MP cameras. The Epson 3000z at its best .jpg setting will fit 256 pictures on a 256 MB card, where my Minolta Z1 will only fit 156 pictures on the same size card. The Minolta hasless compression of the image files. The Epson on the other hand will store pictures in the TIFF format and then can only fit 27 images on a 256 MB card (no compression). I would tend to think that your best bet would be toincrease the compression rather than to reduce the resolution but I'm notvery knowledgableabout such things. I'd also like to hear more on the subject of resolution versus compression.

eric s May 18, 2004 9:42 PM

I believe Puck M is right. The higher compression more resolution is probably better. But try it out and see. But I'm sure its dependent on the style of picture you take. If you have lots of sky in the pictures, they will compress a lot. If you do a lot of nature shots with trees it will compress less.


mslan May 18, 2004 10:42 PM

Thanks guys. That's a big help.

All times are GMT -5. The time now is 5:48 AM.