Approve the Cookies
This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and our Privacy Policy.
OK
Index  •   • New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Guest
New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Register to forums    Log in

 
FORUMS Photography Talk by Genre Macro Talk 
Thread started 11 Nov 2017 (Saturday) 13:03
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

Photographing a moth egg - advice please

 
Trik
THREAD ­ STARTER
Senior Member
Avatar
728 posts
Gallery: 86 photos
Best ofs: 2
Likes: 1443
Joined Apr 2005
Location: Dorset, England
     
Nov 14, 2017 14:00 |  #31

Archibald wrote in post #18496375 (external link)
Hint - shorter focal length will give more magnification.

So, are you suggesting that my wide-angle at, say 50mm, might be better, or only if reversed, please?

Trik


http://www.trikimages.​co.uk (external link)

  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)
Temma
Senior Member
774 posts
Gallery: 49 photos
Likes: 371
Joined Sep 2009
Location: Rocky River, Ohio
     
Nov 14, 2017 14:03 |  #32

Trik wrote in post #18496359 (external link)
I am unsure as to how they work as well - after each movement, I would need to re-focus. Is that correct?

No.

You achieve initial focus slightly in front of the subject. You never touch the lens afterward.
All subsequent focus changes are accomplished by moving the entire camera forward via the rail until you have an area slightly behind the subject in focus.




  
  LOG IN TO REPLY
Temma
Senior Member
774 posts
Gallery: 49 photos
Likes: 371
Joined Sep 2009
Location: Rocky River, Ohio
     
Nov 14, 2017 14:17 |  #33

Archibald wrote in post #18496375 (external link)
Hint - shorter focal length will give more magnification.

I get my greatest magnification from a 50mm Minolta manual reversed onto two sets of extension tubes.

I've been keeping my eye open for a bargain on another manual lens in something like the 28-35mm range.




  
  LOG IN TO REPLY
Wilt
Reader's Digest Condensed version of War and Peace [POTN Vol 1]
Avatar
40,232 posts
Gallery: 1 photo
Likes: 2035
Joined Aug 2005
Location: Belmont, CA
Post edited 8 months ago by Wilt. (4 edits in all)
     
Nov 14, 2017 14:20 |  #34

Trik wrote in post #18496381 (external link)
So, are you suggesting that my wide-angle at, say 50mm, might be better, or only if reversed, please?

Trik

extension / FL = reproduction scale...

As already suggested, use the SHORTEST AVAILABLE FL lens with a specific extension tube in order to obtain highest magnification of subject on focal plane

  • 25mm extension on 100mm FL (focused at infinity) = 25/100 = 1/4 scale image
  • 25mm extension on 50mm FL (focused at infinity) = 25/50 = 1/2 scale image
  • 25mm extension on 25mm FL (focused at infinity) = 25/25 = 1/1 scale image


...of course, the above does not take into consideration the internal focus mechanism's own Minimum Focus Distance (using no extension tube).

Consider how long of an extension tube is needed, to obtain a 1:1

  • 100mm extension on 100mm FL (focused at infinity) = 100/100 = 1/1 scale image at a distance of 400mm from subject to focal plane (4* true FL)
  • 50mm extension on 50mm FL (focused at infinity) = 50/50 = 1/1 scale image at a distance of 200mm from subject to focal plane (4* true FL)
  • 25mm extension on 25mm FL (focused at infinity) = 25/25 = 1/1 scale imag eat a distance of 100mm from subject to focal plane (4* true FL)


BTW, 50mm is NOT 'wide angle' especially on your APS-C frame size 7D or 7DII ! 50mm FL does not become 'wide angle' unitl it is mounted on a medium format camera like a 645 or 6x6 format.

And reversing any lens on a dSLR makes for very inconvenient macro shooting of any live mobile subject because of the methodology needed to shoot with any lens -- particularly for any lens which ordinarily uses electrical contacts to communicate with the body! It is workable (but nevertheless rather awkward) even with a moth egg (which does not move).

You need to give me OK to edit your image and repost! Keep POTN alive and well with member support https://photography-on-the.net/forum/donate.p​hp
Canon dSLR system, Olympus OM 35mm system, Bronica ETRSi 645 system, Horseman LS 4x5 system, Metz flashes, Dynalite studio lighting, and too many accessories to mention

  
  LOG IN TO REPLY
Trik
THREAD ­ STARTER
Senior Member
Avatar
728 posts
Gallery: 86 photos
Best ofs: 2
Likes: 1443
Joined Apr 2005
Location: Dorset, England
     
Nov 14, 2017 18:23 as a reply to  @ Wilt's post |  #35

Temma : Good to know that, after initial focussing, no more is necessary when using a rail.

Wilt : I used the term "wide angle" because my lens is actually a 24 - 105 mm, and only suggested setting it at 50 mm as a possibility for using with extension tubes and/or reversed. Would that particular lens work at 50 mm reversed, though? Also, how can a reversed lens be manually focussed? Wouldn't it be going the wrong way? As you can tell, I have never got involved with this sort of technique and it is all very strange to me.

Trik


http://www.trikimages.​co.uk (external link)

  
  LOG IN TO REPLY
Temma
Senior Member
774 posts
Gallery: 49 photos
Likes: 371
Joined Sep 2009
Location: Rocky River, Ohio
     
Nov 14, 2017 18:47 |  #36

Trik wrote in post #18496557 (external link)
Also, how can a reversed lens be manually focussed?

By moving the camera forward and backward with the rail.

I don't touch the focus ring on my reversed Minolta 50mm.

A lot of this is counterintuitive, but that's how it works.




  
  LOG IN TO REPLY
Trik
THREAD ­ STARTER
Senior Member
Avatar
728 posts
Gallery: 86 photos
Best ofs: 2
Likes: 1443
Joined Apr 2005
Location: Dorset, England
Post edited 8 months ago by Trik.
     
Nov 14, 2017 19:13 as a reply to  @ Temma's post |  #37

Do you set focus at infinity then, Temma? And do you think my 24 - 105 mm, reversed and set at 50 mm, would work?


http://www.trikimages.​co.uk (external link)

  
  LOG IN TO REPLY
Wilt
Reader's Digest Condensed version of War and Peace [POTN Vol 1]
Avatar
40,232 posts
Gallery: 1 photo
Likes: 2035
Joined Aug 2005
Location: Belmont, CA
Post edited 8 months ago by Wilt.
     
Nov 14, 2017 19:13 as a reply to  @ Trik's post |  #38

A 'reversed lens' is an ambiguously used term...it can be either


  1. a lens mounted to another lens, front-to-front, rather than directly to the body
  2. a lens mounted via an adapter which allows the front of the lens to be directly mounted to the body


The problem with #2 is that there is zero control of the lens' automatic diaphram, making it more difficult to focus with wide aperture and then stop down to shooting aperture at the moment of pressing shutter button.
In the case of #1, the lens mounted on the body in the conventional manner has its normal aperture control, but no focus control.

In either event, the focus distance is effectively set by the back of the lens, and the only way to 'focus' is to move camera+lens forward and back.

You need to give me OK to edit your image and repost! Keep POTN alive and well with member support https://photography-on-the.net/forum/donate.p​hp
Canon dSLR system, Olympus OM 35mm system, Bronica ETRSi 645 system, Horseman LS 4x5 system, Metz flashes, Dynalite studio lighting, and too many accessories to mention

  
  LOG IN TO REPLY
Trik
THREAD ­ STARTER
Senior Member
Avatar
728 posts
Gallery: 86 photos
Best ofs: 2
Likes: 1443
Joined Apr 2005
Location: Dorset, England
     
Nov 14, 2017 19:20 as a reply to  @ Wilt's post |  #39

Thanks for the explanation, Wilt, and for pointing out the disadvantage of #2.

I have thought of another drawback to a reversed lens, i.e. my Twin-Lite won't fit...


http://www.trikimages.​co.uk (external link)

  
  LOG IN TO REPLY
Trik
THREAD ­ STARTER
Senior Member
Avatar
728 posts
Gallery: 86 photos
Best ofs: 2
Likes: 1443
Joined Apr 2005
Location: Dorset, England
     
Nov 15, 2017 12:35 as a reply to  @ Trik's post |  #40

I have been window-shopping and like the look of the Fotodiox Pro Extension Tubes (as suggested by Temma) and the Manfrotto Micro Positioning Plate (only forward and back but the adjustments can be less than 1mm according to some reviews I have read). Any thoughts on those choices, please, before I go ahead?

Thanks


http://www.trikimages.​co.uk (external link)

  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)

5,837 views & 1 like for this thread
Photographing a moth egg - advice please
FORUMS Photography Talk by Genre Macro Talk 
AAA
x 1600
y 1600

Jump to forum...   •  Rules   •  Index   •  New posts   •  RTAT   •  'Best of'   •  Gallery   •  Gear   •  Reviews   •  Member list   •  Polls   •  Image rules   •  Search   •  Password reset

Not a member yet?
Register to forums
Registered members may log in to forums and access all the features: full search, image upload, follow forums, own gear list and ratings, likes, more forums, private messaging, thread follow, notifications, own gallery, all settings, view hosted photos, own reviews, see more and do more... and all is free. Don't be a stranger - register now and start posting!


COOKIES DISCLAIMER: This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and to our privacy policy.
Privacy policy and cookie usage info.


POWERED BY AMASS forum software 2.1forum software
version 2.1 /
code and design
by Pekka Saarinen ©
for photography-on-the.net

Latest registered member is macui
476 guests, 371 members online
Simultaneous users record so far is 6430, that happened on Dec 03, 2017

Photography-on-the.net Digital Photography Forums is the website for photographers and all who love great photos, camera and post processing techniques, gear talk, discussion and sharing. Professionals, hobbyists, newbies and those who don't even own a camera -- all are welcome regardless of skill, favourite brand, gear, gender or age. Registering and usage is free.