RAW vs. cRAW

there may be another reason to prefer raw to craw.

when shooting images in continuous mode the rate of image capture (fps) may well slow down somewhat because compressing will also take some time and processor capacity.

at the same time when using craw it will take longer to fill the buffer completely, so you might be able to get more shots in a sequence.

has anybody ever made a comparison between the two types of shooting when using max fps?

it may also be that not every raw converter around that can handle raw files will also be capable of handling craw files.

I have nothing to contribute to the debate on whether or not the loss in cRAW is significant but, as with most things, whether or not to choose cRAW really comes down to one of cost, cost of CF/MS cards and cost of data storage.

With HDD prices down to L90 for 2 Terra bytes and with the cost/MB halving almost every year, the cost of data storage is pretty much a non issue.
The cost of flash memory, on the other hand, is rather more significant.

I have 32MB of CF cards which I found a bit limiting for my A700 plus, only 2x8MB cards are 300x (45MB/sec), the rest are old and slooow.
For my newly acquired A900 and contemplating a 10 day trip, I figured I needed another 2x32MB cards to be safe. Ouch! Nearly L400 and out of the question having just blown the budget (and a bit more) on the A900 + CZ16-35mm.

Anyway, to cut a long story short, I decided on a L160, "Nexto" 320GB portable backup device.
Basically it's a Battery powered, 320GB, 21" SATA hard drive and in size is, unsurprisingly, similar to a standard 21" ext. drive but about twice as thick.
The NexTo LiPol battery does 60GB between recharges and if thats not enough you can buy an external battery which is good for another 80GB. Charging is done via USB or a provided mains PSU.

The device takes CF cards or a whole bunch of Memory stick/SD variants via a second 4in1 slot or via USB.
A microprocessor and eeprom software allows for several functions but I'm only concerned with one (for now) which is, automatic transfer of images from the CF card with data verification. This function is selectable via a simple Menu System on the front LCD.

In use, nothing could be more simple, plug in the CF card and the NexTo recognises the card, creates a new folder, copies the images, verifies the copies by comparing them with the originals and, if all Ok, deletes the CF card ready for it to go back in camera. The whole process takes less than six minutes for my 8GB Sandisk. A different folder name is generated every time you put in a CF (or other) card.

On the trip, the 2x8GB Sandisks were more than adequate for a day's shooting and I didn't need to recharge the NexTo.
At home it connects to my PC for file transfer via eSATA (60MB/sec) or you can use USB.

All I need now is a second NexTo drive so I have a backup in case of failure.

Peekayoh wrote: I have 32MB of CF cards which I found a bit limiting for my A700 plus, only 2x8MB cards are 300x (45MB/sec), the rest are old and slooow. For my newly acquired A900 and contemplating a 10 day trip, I figured I needed another 2x32MB cards to be safe. Ouch! Nearly L400 and out of the question having just blown the budget (and a bit more) on the A900 + CZ16-35mm.

I have 3 16GB Transcend 400x cards, and just purchased a 32GB card for use in my a850. In the US, the 16GB sells for $60 and the 32 for $110. I checked Amazon UK link. The prices are a bit higher, but still 1/2 of your quote.

The Transcend 400x exceeds the a900's 5fps requirements and comes with a lifetime warranty. I've used Transcend almost exclusively since picking up 4GB 133x cards for my KM 7D. 8GB 266x worked well in my a700 and now 400x 16 and 32GB for the full frame. 5+ years, multiple cards and cameras and approaching 100,000 actuations without a single hiccup lets me recommend Transcend without reservation.

Graham

Fuzzphoto wrote: If the difference is both negligable and invisible, why use larger files?

Exactly my opinion as well. I shoot everything (paid jobs) in cRAW and have never been sorry.

Before I made the switch to cRAW I did many comparison shots, outside, inside studio, etc and I could never find a difference in the image after processing. cRAW give me 50% more card space and when shooting a wedding or a sports team, that extra space is quite useful.

Fuzzphoto wrote: If the difference is both negligable and invisible, why use larger files?

Contrarily, if the cRAW is truly loss-less for all intents and purposes, then why would Sony even provide the totally loss-less/unmanipulated RAW in their professional models ?    To fill up the CF-cards faster ?

PS: Nikon also does this. They call it NEF (RAW) and cNEF (cRAW). Nikon only offers full loss-less NEF in their models D300 and higher (in other words, professional models). In all other consumer level models, they don't even attempt to provide NEF and only provides cNEF, because providing the larger NEF (especially at higher 5FPS etc) requires a higher specced data pipeline architecture, than the smaller cNEF files.

I don't think I would ever notice any possible loss of quality in a cRAW file but I still use RAW for all but action sports where I prefer the extra buffer room that cRAW allows. Why not use cRAW all the time? I convert all my RAW and cRAW files to .dng with lossless compression when I import them into Lightroom. The .dng files end up being around the same size as cRAW no matter whether they originate as RAW or cRAW. Since storage space is the same for me I figure there's no reason to take the chance (even though it is almost definitely a non-issue).

I get the feeling this discussion will never end without cold hard facts.

I shoot cRAW for everything. I may switch to RAW for an upcoming wedding.