Archived posting to the Leica Users Group, 1999/06/14
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]m037iu00@cwcom.net wrote: > Horst, > Thanks for the reply, > The Dallmeyer lens you have is quite rare, don't seel it off cheap! The 85/2 was a lens > that I owned at one time, this was also the exchange lens for me acquiring something more > usable, my 28mm Ricoh! > The 75/1.9 is of course my own creation, cobbled together to work on the camera, it will > be interesting to see how well it fares. I also had a 135/4(.5?) Dallmeyer Dalrac which > serviced me very well for many years. > > Having said it is coated it does not refer to Dallcoating on the front lens rim, I am > merely going by the bluish tinges when looking at reflections from light sources, perhaps > this is natural 'blooming' and not a coating at all, perhaps the lens is pre-war? Do you > know if there are any guides to serial number / production for this marque? > > best regards, > > Jem > > Jem, Thanks for your interesting replay.The Super Six I have here does a good job. But i noticed with this lens and other non coated lenses, if they have about 6 or more glass elements, it is wise to increase the exposure by one value. It seems, coating makes quite a big difference to the light transmission. I would say, an uncoated 6 element lens with a f-stop of 2, would be equivalent to a modern coated lens of f 2.8.I don't know the serial numbering of the Dallmeyer lenses, But Marc Small may have a some idea. Natural blooming. I have read in some photographic book, that natural blooming can happen and also improves the lens performance. But I suppose this is a relatively uncontrolled environment and prone to great variations.