Olympus UK E-System User Group
Olympus UK E-System User Group

Join our unique resource for Olympus Four Thirds E-System DSLR and Pen and OM-D Micro Four Thirds photographers. Show your images via our free e-group photo gallery. Please read the e-group.uk.net forum terms and conditions before posting for the first time. Above all, welcome!


Go Back   Olympus UK E-System User Group > Site news and information > Tutorials, Informative & Classic threads

Tutorials, Informative & Classic threads A new e-Group area for all the wonderful tutorials and helpful threads put on here by our members. Tutorials on using software, camera hardware - and feel free to request a tutorial if you need assistance!

Reply
 
Thread Tools Display Modes
  #1  
Old 24th October 2013
Bill Grolz Bill Grolz is offline
Junior Member
 
Join Date: Nov 2012
Location: San Diego, California
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Likes: 0
Liked 0 Times in 0 Posts
E-5 f-45??

I was using my E-5 and started to turn the aperture knob. I was at f22 and turned it a little further and found it went to f45. I now cannot recreate the event. Does anyone know of this. It is not in the manual. Was it a freak one time camera error or does anyone know how to recreate this so I can use the higher f stops?
Reply With Quote
  #2  
Old 24th October 2013
IainMacD's Avatar
IainMacD IainMacD is offline
Full member
 
Join Date: Mar 2008
Location: Drumnadrochit
Posts: 4,012
Thanks: 1,227
Thanked 551 Times in 492 Posts
Likes: 1,915
Liked 866 Times in 242 Posts
Re: E-5 f-45??

Were you by any chance using an EC-20 tele-converter on the lens at the time; this gives you a further 2 stops?
__________________
Iain

E-M5 II, E-M1, E-M1 II, 7.5, 8-18, 12-40, 25, 40-150, 45, 60, 300

Website
Flickr
Reply With Quote
  #3  
Old 24th October 2013
photo_owl photo_owl is offline
Full member
 
Join Date: Jan 2008
Location: Kent
Posts: 1,423
Thanks: 37
Thanked 129 Times in 113 Posts
Likes: 55
Liked 53 Times in 42 Posts
Re: E-5 f-45??

available aperture is a function of the lens/lenses rather than the camera.
__________________
E, Pen and OM-D bodies
43 m43 and legacy glass
loads of flashes and accessories from all the systems
Reply With Quote
  #4  
Old 24th October 2013
Shaw's Avatar
Shaw Shaw is offline
Senior
 
Join Date: Nov 2007
Location: Howe o' the Mearns, Aberdeenshire
Posts: 1,138
Thanks: 202
Thanked 168 Times in 99 Posts
Likes: 457
Liked 160 Times in 60 Posts
Re: E-5 f-45??

Quote:
Originally Posted by IainMacD View Post
Were you by any chance using an EC-20 tele-converter on the lens at the time; this gives you a further 2 stops?
Yes, that's what happens. My E-5 with EC-20 tele-converter shows F45.
__________________
Stewart

My Zenfolio Site
My Portfolio Site

Olympus: E-M1 Mk11 | PEN-F + ECG-4 | XZ-1 | EE-1 Dot Sight Lumix: G9 | LX100 Nissin: i40
Zuiko: 40-150 Pro + MC-14 | 12-100 Pro | 7-14 Pro | 17 | 45 | 60 | OM 135 Leica: 100-400 | 12-60 Samyang: 7.5 fisheye Tamron: 14-150
Reply With Quote
  #5  
Old 24th October 2013
IainMacD's Avatar
IainMacD IainMacD is offline
Full member
 
Join Date: Mar 2008
Location: Drumnadrochit
Posts: 4,012
Thanks: 1,227
Thanked 551 Times in 492 Posts
Likes: 1,915
Liked 866 Times in 242 Posts
Re: E-5 f-45??

Quote:
Originally Posted by Shaw View Post
Yes, that's what happens. My E-5 with EC-20 tele-converter shows F45.
When I use my EC-14 I lose a stop at the wide end (F2.8 becomes F4) and gain a stop at the narrow end (F22 becomes F32)
__________________
Iain

E-M5 II, E-M1, E-M1 II, 7.5, 8-18, 12-40, 25, 40-150, 45, 60, 300

Website
Flickr
Reply With Quote
  #6  
Old 24th October 2013
David M's Avatar
David M David M is offline
Full member
 
Join Date: Dec 2007
Location: A Brit now living in Ontario, Canada.
Posts: 6,612
Thanks: 39
Thanked 678 Times in 640 Posts
Likes: 254
Liked 1,323 Times in 796 Posts
Re: E-5 f-45??

I wonder how bad the diffraction would be at f45?
__________________
It's the image that's important, not the tools used to make it.

David M's Photoblog
Reply With Quote
  #7  
Old 24th October 2013
IainMacD's Avatar
IainMacD IainMacD is offline
Full member
 
Join Date: Mar 2008
Location: Drumnadrochit
Posts: 4,012
Thanks: 1,227
Thanked 551 Times in 492 Posts
Likes: 1,915
Liked 866 Times in 242 Posts
Re: E-5 f-45??

I am not sure of the physics of this as the aperture size at F45 with the EC-20 would be the same size as the aperture at F22 with no converter so would diffraction be any worse?
I know that it does happen but not why it happens (F45 with EC-20).
I am way out of my depth with trying to understand this so maybe one of our friendly experts would like to help me out?
__________________
Iain

E-M5 II, E-M1, E-M1 II, 7.5, 8-18, 12-40, 25, 40-150, 45, 60, 300

Website
Flickr

Last edited by IainMacD; 24th October 2013 at 09:38 PM. Reason: re-ordered
Reply With Quote
  #8  
Old 24th October 2013
David M's Avatar
David M David M is offline
Full member
 
Join Date: Dec 2007
Location: A Brit now living in Ontario, Canada.
Posts: 6,612
Thanks: 39
Thanked 678 Times in 640 Posts
Likes: 254
Liked 1,323 Times in 796 Posts
Re: E-5 f-45??

Sorry Iain, it's 34 years since I studied optics.
__________________
It's the image that's important, not the tools used to make it.

David M's Photoblog
Reply With Quote
The Following User Says Thank You to David M For This Useful Post:
IainMacD (24th October 2013)
  #9  
Old 25th October 2013
Nick Temple-Fry's Avatar
Nick Temple-Fry Nick Temple-Fry is offline
Full member
 
Join Date: Nov 2007
Location: Wiltshire
Posts: 4,395
Thanks: 17
Thanked 190 Times in 142 Posts
Likes: 0
Liked 5 Times in 5 Posts
Re: E-5 f-45??

Quote:
Originally Posted by IainMacD View Post
I am not sure of the physics of this as the aperture size at F45 with the EC-20 would be the same size as the aperture at F22 with no converter so would diffraction be any worse?
I know that it does happen but not why it happens (F45 with EC-20).
I am way out of my depth with trying to understand this so maybe one of our friendly experts would like to help me out?
Whether I'm friendly or an expert I'll leave to others to judge.

But a teleconverter basically works by taking the central part of an image and spreading it out across the frame size. So it wont add to the diffraction inherent from the aperture but it will spread it across more pixels so it will be more visible.

There will be a second order of diffraction as effectively the teleconverter is a lens with a fixed aperture, so that will create its own diffraction pattern. But that aperture will be relatively large (compared to F22 on the main lens) so I'll need convincing that it'll be observable.

Nick
__________________
Nick Temple-Fry

Medicine as a science ranks somewhere between archaeology and economics.

www.theChurchPhotographer.co.uk 90 Churches -- Fairford St Mary's, exceptionally splendid
www.temple-fry.co.uk
Reply With Quote
The Following User Says Thank You to Nick Temple-Fry For This Useful Post:
IainMacD (25th October 2013)
  #10  
Old 25th October 2013
Zuiko's Avatar
Zuiko Zuiko is offline
Administrator
 
Join Date: Nov 2007
Location: Dunmow, Essex
Posts: 22,186
Thanks: 1,991
Thanked 3,175 Times in 2,480 Posts
Likes: 3,447
Liked 4,504 Times in 2,141 Posts
Re: E-5 f-45??

We all know that diffraction becomes an issue from around F8 onwards and Ian has in the past posted a series of crops which demonstrate this so it's safe to say there will be a noticable loss of quality. How noticable will depend upon how close you pixel peep and how large you print. If you need an aperture that small for a particular reason, go ahead and use it, if not play safe and select a much larger aperture.
__________________
John

"A hundredth of a second here, a hundredth of a second there even if you put them end to end, they still only add up to one, two, perhaps three seconds, snatched from eternity." ~ Robert Doisneau
Reply With Quote
  #11  
Old 25th October 2013
David M's Avatar
David M David M is offline
Full member
 
Join Date: Dec 2007
Location: A Brit now living in Ontario, Canada.
Posts: 6,612
Thanks: 39
Thanked 678 Times in 640 Posts
Likes: 254
Liked 1,323 Times in 796 Posts
Re: E-5 f-45??

That sounds about right Nick.
__________________
It's the image that's important, not the tools used to make it.

David M's Photoblog
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 12:28 AM.


The Write Technology Ltd, 2007-2019, All rights reservedAd Management plugin by RedTyger