I�d say all telephoto lenses are long focus - because they do indeed have long focal length. But all long focus lenses are not telephotos because - like you say - telephoto lenses are optically made physically shorter than their focal lengths. And yes, only some inexpensive long focus lenses are not telephoto designs but it was not always so. E.g. some really expensive Leitz lenses were not telephotos. All the best! Raimo K Personal photography homepage at: http:\\www.uusikaupunki.fi/~raikorho
----- Original Message ----- From: "J. C. O'Connell" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, June 26, 2004 7:19 PM Subject: RE: pentax-discuss-d Digest V04 #680 > Long focus and telephoto designs are mutually exclusive. Long focus > designs > are physically approximately the same length as the optical focal > length. > Telephoto designs on the other hand are physically shorter than the > focal length. > Nearly all lenses for 35mm SLR over 105mm are telephoto designs rather > than > long focus designs for handling reasons. You want/need a telephoto, not > a long focus lens. > One that is low cost but outstanding is the RMC Tokina 400mm 5.6. It was > made > in both M42 Screw and non-A K for pentax. I have one in M42 and it is > really really good. > these sell for $100-150 on ebay from time to time. > jco > > -----Original Message----- > From: Lorin Mackey [mailto:[EMAIL PROTECTED] > Sent: Saturday, June 26, 2004 11:53 AM > To: [EMAIL PROTECTED] > Subject: Re: pentax-discuss-d Digest V04 #680 > > > Good Morning jco; > I detest showing my ignorance like this but, I was under the > impression that long focus was the proper terminology for any telephoto > type lens. > Would you like to make a suggestion as to which would be better for me > ? > My primary interest is birds and animals at a range of 1000 feet or > less. My 135 lens does not do it for me. Lorin > > > -----Oprindelig meddelelse----- > > Fra: J. C. O'Connell [mailto:[EMAIL PROTECTED] > > Sendt: 26. juni 2004 05:03 > > Til: [EMAIL PROTECTED] > > Emne: RE: Long Focus Lens for Spotmatic > > > > > > Do you really mean long focus or will a telephoto type lens be > > sufficient? Long focus M42 lenses are rare in that length. > > jco > >
