Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-25-2012, 06:00 PM   #16
Veteran Member




Join Date: Feb 2011
Photos: Gallery
Posts: 573
If you want to get 5x magnification, you simply need to create an extension 6x the focal length. For a 105mm lens, you simply need 630mm between the lens and the image plane. For a 200mm lens, you need 1200mm between the lens and the image plane.

M = (d ) / where d is the lens to image plane distance.

This is really why microscopes are so popular for imaging.

10-26-2012, 09:37 AM   #17
New Member




Join Date: Aug 2012
Posts: 23
Original Poster
Sounds good! I am getting the bellows - so I can combine with the 200 or 105 plus extension tubes - should do the job...
10-26-2012, 10:57 AM   #18
Pentaxian




Join Date: Feb 2009
Location: Arizona
Posts: 911
Klaus, I'm doubtful that the formula in question works for the 35mm fisheye since this lens has unequal image magnification across the frame. Paraxial areas have higher magnification than the marginal areas. Pentax does not list the Fisheye in their Extension Tube/Close up booklet-probably for this reason.
10-26-2012, 12:53 PM   #19
Senior Member
klaus123's Avatar

Join Date: Apr 2011
Location: Germany
Posts: 210
QuoteOriginally posted by desertscape Quote
Klaus, I'm doubtful that the formula in question works for the 35mm fisheye since this lens has unequal image magnification across the frame. Paraxial areas have higher magnification than the marginal areas. Pentax does not list the Fisheye in their Extension Tube/Close up booklet-probably for this reason.
I tried it (just in the view finder): The focal distance with all 3 distance rings is exactly at the front lens - on a K7 with adaptor that means, that one of the forum smileys is a full screen picture (~ 3:1)

10-30-2012, 11:35 AM   #20
New Member




Join Date: Aug 2012
Posts: 23
Original Poster
So..., I upgraded and now I am where I wanted to be with magnification, for now at least... - It's a serious pain to take a Photo (highest magnification)..., will post the outcome. Anyways, it's a felxible setup!

Name:  IMG_0815.jpg
Views: 88
Size:  103.3 KB
10-30-2012, 11:42 AM   #21
New Member




Join Date: Aug 2012
Posts: 23
Original Poster
QuoteOriginally posted by klaus123 Quote
I tried it (just in the view finder): The focal distance with all 3 distance rings is exactly at the front lens - on a K7 with adaptor that means, that one of the forum smileys is a full screen picture (~ 3:1)
With full magnification I get the smiley in full frame... Is there any way to just take it times four (~12:1) - compared to small format? I am really not up for crunching numbers (formula)...
10-30-2012, 03:23 PM   #22
Senior Moderator
Loyal Site Supporter
Nass's Avatar

Join Date: Aug 2009
Location: The British Isles
Photos: Gallery
Posts: 2,251
Good grief
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!
camera, macro, medium format
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Zeiss Macro 50mm f/2 ZK Macro-Planar T* vs Pentax-A 50mm Macro kbrede Pentax SLR Lens Discussion 13 07-10-2012 11:07 AM
Macro benefits? dedicated Macro VS Telephoto/Macro choices Tricktech Pentax SLR Lens Discussion 11 07-01-2012 11:17 AM
For Sale - Sold: DA 35mm/2.8 Macro Ltd, FA 50mm, DA L55-300mm, Pentax Macro Bellow Unite I (US) yurko_yr Sold Items 10 03-16-2011 07:09 PM
For Sale - Sold: Pentax primes (F50/1.7, F50/2.8 macro, F100/2.8 macro, FA100/2.8 macro) dgaies Sold Items 5 11-02-2010 11:51 AM



All times are GMT -7. The time now is 06:02 PM. | See also: NikonForums.com, CanonForums.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