Magic Memory Cards?

magpieant

magpieant

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Hi Everyone.

Here's a question for you all .... I can't understand this - too technical! :)

Formatted a memory card yesterday (2gig). Placed it in my D50, which is on RAW setting. Camera states that the card will hold 274photos on RAW setting.

Go to Chester Zoo and manage to get 369 photos on said card, again, still in RAW setting.

How does that work then?

Answers on a postcard to the usual address please ..... ;)

ANTH
 
Not sure if this is the answer, but I noticed on my camera the amount of shots varied with the ISO setting. With a 1 gb card I get 160 shots at ISO100 & 146 shots at ISO 3200.
 
The display for the amount of pictures is based upon a standard image size, however when you shoot not all images will be that size hense you will get more pictures. I shoot RAW + Jpeg on my D50 with a 1gig card, it shows 120 pictures but I know that I can get at least 160 pictures on it :) .
 
:agree: not all RAW images are the same size so the camera can only guess at how many shots you'll get on your card based on an average. I can always squeeze about an extra 20 shots on a 1 gig CF card.
 
Or to put it another way RAW uses lossless compression of the data. Shoot a plain blue sky and it is easy to compress to a small file. Shoot a leafy tree and grass etc and it can't be compressed as much without losing detail.

So how many shots you get depends on what you shoot.
 
Cracking explanations as always. Thank you!!!

I did change the ISO settings at times due to low light, so that has obviously impacted as well as the various size files.

Cheers again.

Anth.
 
It's also down to the level of detail in your image, more detail = bigger file, try a few shots to experiment for yourself. :)
 
Dan Leach said:
Its not just RAW, and i dont think its down to ISO. On my eos 400d if i take 20 jpg's they will generally range from 2.8 - 5.6mb
Click to expand...
Higher ISO files do, in general, have larger file sizes - the image noise at higher ISOs is more difficult to compress.

JPGs will vary in size because of their very nature. They employ a lossy compression algorithm so simple scenes with large areas of smooth colour can be and are compressed more than complex scenes like foliage for example.

RAW files use lossless compression so the content doesn't have the same bearing on the file size and hence the part played by the ISO becomes more obvious.
 
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