Astronomy, Photography and Weather
August 15, 2020, 06:41:50 pm
Welcome, Guest. Please login or register.

Login with username, password and session length
News: IAA lecture programme continues alternate Wednesdays from September - an excellent programme of lectures- Queens University Belfast - Bell Lecture Theatre. Also keep an eye out for the Summer Events
  Home Help Search Gallery Staff List Login Register  

Taped Contacts - 1.4 X

Pages: [1]
Author Topic: Taped Contacts - 1.4 X  (Read 367 times)
Hero Member
Posts: 1631

Gloucester : UK

View Profile
« on: June 20, 2009, 06:50:07 pm »

 Yes, that's a fair point re. the camera being fooled, so to test  that I  used the 70-200 and took a photo at the F4  it  appeared  to retain and then dropped it to f5.6 and there was a difference in the exposure- the f5.6 photo in the LCD was, of course darker , so it does seem that it actually does give you f4.  BUT lol.. I've just had a thought..I can hear you knowledgeable gentlemen saying "Ah but how do you know that it wasn't taking it at f5.6 (in reality) and the next photo you took was infact  f8 - well, that's a good point I didn't think of that at the time so what I'll do is to to take one photo at f4 with the extender taped and then take the extender off and take one at f5.6 and see if there's  any difference-- is this correct ?

My concern, though,  is that I can hear the lens hunting and wonder if it may damage the contacts somehow. When it hunts and assuming there is time, I can can go to manual get it focused and switch to auto and take the photo,  as and when, there may be a minimum of adjustment but no hunting. What I also found was that the hunting problem is mainly with hand held ,when it was tripod mounted the auto focus was fast, hardly, if any difference. However, the focusing without the extender was instant .
Report Spam   Logged

Pages: [1]
Jump to:  

Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum

Powered by SMF | SMF © 2016, Simple Machines
Privacy Policy