Should be possible - just hack one of the short extension tubes surely so that the lens always stops down? Build in a 0.7 teleconvertor with a lever to control the stop down and everyone will be happy - except that outside Japan you will probably only be able to buy the grren one which doesn't match any lenses or bodies!
> -----Original Message----- > From: Cotty [mailto:[EMAIL PROTECTED] > Sent: 12 October 2003 21:26 > To: pentax list > Subject: Re: Old lenses and *ist D > > > On 12/10/03, [EMAIL PROTECTED] disgorged: > > >No extra code is required for stopdown metering with M42 lenses. If > >the code for the camera is properly written, (I'll make no bets on > >that, I've seen some awful code, but assuming they did a > good job) then > >the amount of code used a.) to make the camera not > >fire when a lens isn't set to A, or doesn't have an A > setting, (if properly > >written that should > >be the same code, it's looking at the same sensor), or b.) > Overrides that > >function to turn off > >the meter and allow the shutter to fire, could be re-written > to call the > >module to stop down the > >lens and the module to turn the meter on, thus giving K/M > lenses stop down > >metering at least. > > This is interesting. To get the D60 to fire with the M42/EOS > adapter aboard, I had to physically grind off a small bit of > flange where it contacts a small 'pin' on the camera. > Presumably this pin on the camera tells the electronics that > there is a lens in place and can it detect the electrical > contacts on the lens? If it can (EOS lens) it allows the > shutter to work. If it can't (M42/EOS adapter) it won't allow > the shutter to fire. Knowing that the camera will fire with > no lens, no nothing in the bayonet, I figured that to remove > the 'pin' on the camera would be out, cuz I obviously want to > use other EOS lenses, or lose the bit of metal that contacts > the pin. This I did and hey presto it fires, and allows stop > down metering in manual and AV modes. This was the basis of > my idea to construct an EOS mount on the back of a Pentax lens. > > Given the above info, is there any way that the back of a K > mount lens could be modified to let the *ist D fire using > stop down metering in similar modes? > > > Cheers, > Cotty > > > ___/\__ > || (O) | People, Places, Pastiche > ||=====| www.macads.co.uk/snaps > _____________________________ > Free UK Mac Ads www.macads.co.uk > >
