Dear all,
I eventually tried the Eye-fi option and, now that it is working reliably, am very happy with the product. See my review at http://www.amazon.com/review/R2ADGC350OJK3F/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B002UT42UI&nodeID=&tag=&linkCode=
Thanks again,
Jolyon

Thanks again, Algi.
Do you (or anyone) know if an Eye-Fi card will work with a Pentax ist DS? Obviously, if it works, all I have to do is take the shot, wait for it to arrive at the laptop and either keep it or delete it. It would be almost as good as using the laptop as a live viewfinder. Yours, Jolyon

Thanks again, Algernon, amoringello and Terry. Still no luck with RA but I am looking into the Eye-Fi option. Will that enable me to use the laptop as a viewfinder?
Yours,
Jolyon

Thanks to Mongoose and Algernon. I feel that I'm getting there. Did you have the camera's SD card in?
I still need someone with a Mac and an ist DS to confirm.

Thanks, Mongoose.
I think the firmware has been updated. I bought the camera second hand last year and I think that was one of the selling points.
How can I find the version number and is it possible to revert to the original?
I do have the original disk, S-SW28, but it doesn't work on this OS. It's probably a PC disk. Pentax Installer just opens a blank window.
Yours,
Jolyon

For those who wish to operate their *ist DS cameras from laptop computers, aka tethering, here are the links for the software, Remote Assistant:

Mac OS 10. http://www.pentaximaging.com.evohst.org/files/scms_docs/REMOTE%20Assistant_e.sit

Windows. http://www.pentaximaging.com.evohst.org/files/scms_docs/INSTRA01.EXE

However, I still haven't got this working on a MacBook Pro, OS X 10.5.8. Remote Assistant will open but all its functions are greyed out, indicating to me that it can't find the camera.

I have tried this with the camera's card in and out but it seems to make no difference. Logically, I would expect that the card should be out so that the computer doesn't see it as just another external drive.

I think I need to install driver software for a Pentax *ist DS on my Mac. This might have come with the original software for the camera but that disk is now unreadable and my attempts to download it from Pentax have been in vain. Hoya seems not to have bothered to keep those links unbroken...

Any suggestions are more than welcome.

Yours,
Jolyon

No, I'm afraid it's a no go. I got the following reply from Pentax Australia:

Dear Customer,
Remote Assistant does not support ist DS.
Kind regards,
Consumer Support

So, unless anyone knows of an alternative, it's back to the newspaper copying for me. Thanks anyway, Jolyon

Thanks to all who responded. The fact that Remote Assistant doesn't give a live view won't worry me. It sounds great.
So far, I have not been able to download a copy of RA for the *ist D and Mac OSX from http://www.pentax.jp/english/support/download_digital.html. However, I now know what I'm looking for...
Yours,
Jolyon

Does anyone know if this is possible? I have to do a pile of newspaper copying and bending over to look down the viewfinder is breaking my back! If I could connect the Pentax ist to my Macbook Pro, get the image I need and fire away, life would be easier... Yours, Jolyon.