Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-03-2012, 02:50 AM   #91
Site Supporter
markku55's Avatar

Join Date: Dec 2011
Location: Hanko, Finland
Posts: 195
Original Poster
I know that this is complete wrong place to talk about languages, sorry that I started this, but I have to tell one story still.
It was about mid sixties when one language professor told that the best candidate as a world language is Finnish.
Reason to that is that all letters spells always in same way. Example in English the letter a spells different depending on word: In auto or car you spel it like it is always spells in Finnish, but in lake you spell it like written in Finnish leik.
In Finnish a long vocal is always written with two vocals, if you spell some word with double consonat, you also write it with two consonat etc. Finnish grammar may not be so simple, but you learn quite fast to speak and even write Finnish.
I was'nt so interested on learning Swedish or English in school, but later during my working carrier I had to speak and write English, close to every day, so I have learned my simple English because of I needed it.
I have learned also during years, that it is not so important to write or speak 100% pure English, most important is to be understood and to understand.

03-03-2012, 05:36 AM   #92
Senior Member




Join Date: Mar 2008
Location: Lisbon
Posts: 142
QuoteOriginally posted by markku55 Quote
I'm an old guy, and I think that metal is metal and plastic is plastic.
I could tell you a sad story of a plastic bike Itera, but may be you only read its history:
Plastic bicycle - Wikipedia, the free encyclopedia
The stupid guys from Volvo believed on a bike made nearly 100% of plastic, that was a huge mistake and a really expencive disaster.
There are several places in where plastic is a good solution, may be even the best one, but not in a lens mount
Sorry to inform but polimers are here to stay. Since then polymers have evolved a lot. Think about carbon fiber tripods. Even carbon fiber bycicles are available today.

Aparently those "stupid guys from Volvo" where on the right track, just like some other "stupid guys" like Da Vinci when he designed the chain.

Polymers can be extremely resistant and a lot less expensive than metal. Newer polymers will replace most metallic parts eventually.
03-03-2012, 09:49 AM   #93
Site Supporter
markku55's Avatar

Join Date: Dec 2011
Location: Hanko, Finland
Posts: 195
Original Poster
QuoteOriginally posted by lpfonseca Quote
Sorry to inform but polimers are here to stay. Since then polymers have evolved a lot. Think about carbon fiber tripods. Even carbon fiber bycicles are available today.

Aparently those "stupid guys from Volvo" where on the right track, just like some other "stupid guys" like Da Vinci when he designed the chain.

Polymers can be extremely resistant and a lot less expensive than metal. Newer polymers will replace most metallic parts eventually.
You have complete right, but you should know which kind and where you use polymers. In the case of Itera bike, the whole consept was wrong, the materials they used was not meant to be used in that kind of purposes and alreay the construction itself was poor.

Talking about lens bajonet made of plastic, I know that there is problems with broken flanges etc.. It is obvious that a heavy lens and big camera body, there CAN NOT be used plastic in the bajonet to fix the lens to the body. Have you seen any?
03-03-2012, 09:57 AM   #94
Veteran Member
KungPOW's Avatar

Join Date: Nov 2007
Location: Vancouver, Canada
Photos: Gallery
Posts: 1,702
You know that the lens mount on most cameras is actually screwed into a plastic base inside the camera. K-7/K-5 included.

03-03-2012, 11:01 AM   #95
Site Supporter
markku55's Avatar

Join Date: Dec 2011
Location: Hanko, Finland
Posts: 195
Original Poster
QuoteOriginally posted by KungPOW Quote
You know that the lens mount on most cameras is actually screwed into a plastic base inside the camera. K-7/K-5 included.
That might be today so, but that is not the point, the sharp edges, especially the inner edges, on a bayonet are the most wournable places, there will be the highest stress and at last the plastic flange will broke.
My poor English do not give me the possibility to explane strength matters, but believe me strength calculations have not changed after I graduated as an machine construction engineer 1974.

From my side it is ok to stop arguing about this bayonet matter, but I'm so oldfashion guy that according to my opinnion, a lens mount bayonet must be made of metal, what ever plastic there is available
03-03-2012, 02:37 PM   #96
Pentaxian
thibs's Avatar

Join Date: Jun 2007
Location: Belgium
Photos: Albums
Posts: 5,161
QuoteOriginally posted by markku55 Quote
Talking about lens bajonet made of plastic, I know that there is problems with broken flanges etc.. It is obvious that a heavy lens and big camera body, there CAN NOT be used plastic in the bajonet to fix the lens to the body. Have you seen any?
I think everybody agrees. Which is why, in Pentax world at least, plastic boyonet are exception and are used only in low cost small lenses.
So, in the end... lots of noise for nothing ?
03-04-2012, 03:04 AM   #97
Site Supporter
markku55's Avatar

Join Date: Dec 2011
Location: Hanko, Finland
Posts: 195
Original Poster
QuoteOriginally posted by thibs Quote
So, in the end... lots of noise for nothing ?
You have sooo right, but I'm a guy who can not keep quiet if some one challenge me, sorry
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
cp, pentax news, pentax rumors
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Machinery 2012 Houston Auto Show - Porsche's New Gen 911 [9 IMG] Sailor Post Your Photos! 15 02-09-2012 06:00 AM
Machinery 2012 Houston Auto Show - Lambo Aventador Sailor Post Your Photos! 14 02-05-2012 07:42 AM
Picture of the Week POTW #197: January 1 2012- January 15 2012 wolfiegirl Weekly Photo Challenges 86 01-15-2012 03:02 AM
Greetings for 2012 EggMan Welcomes and Introductions 2 01-02-2012 09:56 PM
2012 according to Wall St Nesster General Talk 2 09-14-2010 01:17 PM



All times are GMT -7. The time now is 04:51 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top