Home · Register · Join Upload & Sell

Moderated by: Fred Miranda
Username  

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Sony Forum | Join Upload & Sell

1       2       3              40      
41
       42              104       105       end
  

Archive 2016 · Front-End Filter Improves Corner Smearing

  
 
MIRANDA1
Offline
• • •
Upload & Sell: Off
p.41 #1 · p.41 #1 · Front-End Filter Improves Corner Smearing


In the wall test the left side is noticeably sharper than the right in the corners when viewd at 100%


Feb 01, 2017 at 11:31 PM
artur5
Offline
• • •
Upload & Sell: Off
p.41 #2 · p.41 #2 · Front-End Filter Improves Corner Smearing


That might be due to different reasons : 1- adapter issue . 2- lens issue 3- filter not correctly centered inside the "sandwich" of step rings.
If, when removing the front filter, both sides of this wall are equally sharp ( or unsharp) then the filter alignment is the problem. Wideangle lens are merciless. It takes only a very minor tilt of the front lens to produce uneven results in the corners.



Feb 02, 2017 at 05:16 AM
artur5
Offline
• • •
Upload & Sell: Off
p.41 #3 · p.41 #3 · Front-End Filter Improves Corner Smearing


Fred Miranda wrote:
....
By looking at the Proxar 1m lens, I believe it is a 'positive meniscus' optical design with one convex and one concave surface. (Instead of a convex and a plano found on a PCX lens)
In other words it's a convex meniscus (thicker in the middle than at the edges) and a similar optical design as the one found in glasses for folks whot are long-sighted. Basically these lenses shift the plane of focus from infinity to the distance correspondent to the focal length of the close-up lens.
I'm not sure how the Hoya close-up lens is designed but it probably
...Show more

Yes, I have a Hoya and other close-up lenses of different brands and all are like this, convex-concave designs thicker in the center than in the corners.



Feb 02, 2017 at 05:36 AM
HaruhikoT
Offline
• •
Upload & Sell: Off
p.41 #4 · p.41 #4 · Front-End Filter Improves Corner Smearing


padam19 wrote:
Hi all,
Do you think I can use a 5m PCX filter on a Summilux 35/1.4 ASPH (pre-fle) as well?

I'm not sure if infinity focus is adjustable the same way as with the ZM 35/1.4, or if it is the optimal piece of glass for it. Thanks.


Here are simulated MTFs.
https://farm1.staticflickr.com/646/32513037522_f58715b071_o_d.jpg


As always please note the Lux 35's original aberrations are not included here.
I got the exit pupil distance from lensrentals article.
I also edited my model parameters to match the specified optical vignetting of lux 35 asph pre-fle..

With 5m PCX, corner sharpness and field curvature will be improved, but there will be noticeable mid-zone dip at wide-open. The mid-zone recovers from f1.7 and the whole area will be very good at f2.8 or higher stop.

To reach infinity, too-short M-E adapters (Pixco or Fotodiox) may work, as well as ZM35/1.4.
I can't recommend you to remove shim inside such expensive lens.



Feb 02, 2017 at 09:45 AM
padam19
Offline

Upload & Sell: Off
p.41 #5 · p.41 #5 · Front-End Filter Improves Corner Smearing


Thanks for taking the time, looks worthwhile for an experiment (Why did I sell the Hawks adaptor in the first place )

Dear Bastian, may I ask, do they ship the filter outside Germany as well?

I would be nice to try before buy and I do visit Germany for time to time, but not that area unfortunately


Installation is the same as the Contax G28?



Feb 03, 2017 at 02:23 AM
BastianK
Offline
• • •
Upload & Sell: Off
p.41 #6 · p.41 #6 · Front-End Filter Improves Corner Smearing




padam19 wrote:
Thanks for taking the time, looks worthwhile for an experiment (Why did I sell the Hawks adaptor in the first place )

Dear Bastian, may I ask, do they ship the filter outside Germany as well?

I would be nice to try before buy and I do visit Germany for time to time, but not that area unfortunately

Installation is the same as the Contax G28?

Optosigma has different distributors for different countries,
contact Optosigma.com first, they will forward you to your specific distributor.
Delivery time can be very long though...
If there is someone with the Leica lens near Stuttgart reading this he is invited to contact me so we can check out the results.

Installation is pretty much the same for all lenses,
only the x -> 55mm step up ring needs to match the diameter of your lens.



Feb 03, 2017 at 03:03 AM
teeraash
Offline

Upload & Sell: Off
p.41 #7 · p.41 #7 · Front-End Filter Improves Corner Smearing


Hi HaruhikoT,
Would the 5M PCX work on the 50/1.4 ASPH as well? Could you do a simulation on this lens in case that you have the required parameters? Thanks.



Feb 03, 2017 at 06:32 AM
HaruhikoT
Offline
• •
Upload & Sell: Off
p.41 #8 · p.41 #8 · Front-End Filter Improves Corner Smearing


teeraash wrote:
Hi HaruhikoT,
Would the 5M PCX work on the 50/1.4 ASPH as well? Could you do a simulation on this lens in case that you have the required parameters? Thanks.

Would try to simulate but I can't find Exit pupil distance or Chief Ray Angle of the lens.
Does anyone find these values on the web?



Feb 03, 2017 at 08:35 AM
GMPhotography
Offline
• • • • • • •
Upload & Sell: On
p.41 #9 · p.41 #9 · Front-End Filter Improves Corner Smearing


so I got some more rings for the ZM 25, more for the hood side of it more than anything else and i like this setup. So from lens itself going out 46-55 with Proxar inside that 55-52 step down with 52mm retaining ring. This holds the lens the best. I feel the retaining ring is the key to proper alignment inside this rig. Than for the hod part I used a 52-55 step up which gives nice clearance from the Proxar and acts as a hood and protection, plus it looks better. Ill try the Hoya but Im done with this setup as I feel for me at least what I want












Feb 03, 2017 at 09:37 AM
GMPhotography
Offline
• • • • • • •
Upload & Sell: On
p.41 #10 · p.41 #10 · Front-End Filter Improves Corner Smearing


My 5m just showed up for my ZM 35 . Yahoo


Feb 03, 2017 at 12:36 PM
BastianK
Offline
• • •
Upload & Sell: Off
p.41 #11 · p.41 #11 · Front-End Filter Improves Corner Smearing


GMPhotography wrote:
My 5m just showed up for my ZM 35 . Yahoo

Still waiting for mine. Still said to arrive on friday 10th...

But I can share some good news for Voigtlander 35mm 1.7 fans.
Phillip has sent me the lens (and a "meymoon" step up ring, never ever buy from that junk "brand"!!!)
and I put my Eksma Optics 5m filter on.
Remember: this filter is not the same as the Opto Sigma 5m filter as it is 2mm thicker and it didn't
yield results as good on my ZM 35mm 1.4 (huge midezone dip even at f/5.6).

But it seems to be a great fit for the VM 35mm 1.7:

Sharpness_Vm_35mm_1.7_center_5m by Bastian Kratzke

Keep in mind though: I bought an uncoated filter form Eksma which leads to some issues with the sun in the frame,
as you can see in this album.
They also offer to add multicoating but this will not only increase the price but also the delivery time (to 5 weeks).

PS: with my slowly becoming famous Fotodiox L/M-Nex adapter infinity focus is possible with mounted 5m filter and without any modifications on the lens.
Infinity hard stop is also working starting at f/2.8.



Feb 03, 2017 at 01:09 PM
GMPhotography
Offline
• • • • • • •
Upload & Sell: On
p.41 #12 · p.41 #12 · Front-End Filter Improves Corner Smearing


Looks good


Feb 03, 2017 at 01:45 PM
MIRANDA1
Offline
• • •
Upload & Sell: Off
p.41 #13 · p.41 #13 · Front-End Filter Improves Corner Smearing


I finally recieved my ZM25 today and had an opportunity to test it out with and without the Proxar 1m. The differences are pretty astonishing, I'm seeing similar results to what Guy posted. I'm struggling with two minor irritants at this point however. My particular lens didn't have any silver shims, there were two gold and two bronze shims, after messing around with infinity focus I'm finding that with only the bronze shim on both my Novoflex and Voigtlander adapter that infinity is achieved just slightly before the hardstop, with the Gold shim I can't focus to infinity before I hit the hard stop. A silver shim likely would be the solution or a Hawk's adapter with an adjustable infinity stop wouldtake care of this. With the TAP in manual more you can focus well past infinity in my current setup.

The other issue I've noticed is that I am unable to add a final step-up ring to act as a "hood" similar to how Guy set his up, I start getting mechanical vignetting and get progressively worse with the hight aperture.



Feb 03, 2017 at 02:37 PM
sebboh
Offline
• • • • • •
Upload & Sell: Off
p.41 #14 · p.41 #14 · Front-End Filter Improves Corner Smearing


BastianK wrote:
Still waiting for mine. Still said to arrive on friday 10th...

But I can share some good news for Voigtlander 35mm 1.7 fans.
Phillip has sent me the lens (and a "meymoon" step up ring, never ever buy from that junk "brand"!!!)
and I put my Eksma Optics 5m filter on.
Remember: this filter is not the same as the Opto Sigma 5m filter as it is 2mm thicker and it didn't
yield results as good on my ZM 35mm 1.4 (huge midezone dip even at f/5.6).

But it seems to be a great fit for the VM 35mm 1.7:
https://c1.staticflickr.com/1/505/32534945762_9e0f67a3d2_o.jpg
Sharpness_Vm_35mm_1.7_center_5m by Bastian Kratzke

Keep in mind though:
...Show more

sweet!

any idea if it corrects the mid distance field curvature for narrow dof shots as well as it does for the zm 35/1.4?




Feb 03, 2017 at 02:47 PM
Fred Miranda
Offline
Admin
Upload & Sell: On
p.41 #15 · p.41 #15 · Front-End Filter Improves Corner Smearing


MIRANDA1 wrote:
I finally recieved my ZM25 today and had an opportunity to test it out with and without the Proxar 1m. The differences are pretty astonishing, I'm seeing similar results to what Guy posted. I'm struggling with two minor irritants at this point however. My particular lens didn't have any silver shims, there were two gold and two bronze shims, after messing around with infinity focus I'm finding that with only the bronze shim on both my Novoflex and Voigtlander adapter that infinity is achieved just slightly before the hardstop, with the Gold shim I can't focus to infinity before I
...Show more

I believe that shim thickness is batch variant. I've seen two ZM 35/1.4 lenses from different batches that had different shim thicknesses (shim colors were different).
So, what works for Guy may not work for you and you will have to play around removing shims and testing the lens to see if infinity focus is achieved by a modified shim combination.

The same goes for step-up and step-down rings. Different brands may have different lengths and that may influence vignetting.



Feb 03, 2017 at 02:49 PM
GMPhotography
Offline
• • • • • • •
Upload & Sell: On
p.41 #16 · p.41 #16 · Front-End Filter Improves Corner Smearing


Make sure your 52mm retaining ring is fully down. Fooled me too . You can tell if you hear the lens shaken inside the mount. When fully down it makes no sound and is tight


Feb 03, 2017 at 02:49 PM
rhawidantas
Offline
• •
Upload & Sell: Off
p.41 #17 · p.41 #17 · Front-End Filter Improves Corner Smearing


Hi Bastian,

Thanks for spending the time with the tests.

I have to say I am a bit overwhelmed by the amount of info in this thread on where to buy and how assemble the lens for the Voigt 35mm 1.7.

Will you guys be writing a blog post on where to buy the material and if not would be so kind in condensing in one post?

thanks once again,
Rhawi Dantas



Feb 03, 2017 at 02:54 PM
rji2goleez
Offline
• • • • • •
Upload & Sell: On
p.41 #18 · p.41 #18 · Front-End Filter Improves Corner Smearing


I just placed my order for the Opto Sigma optic for my Zeiss Distagon 35/1.4ZM. It's got a 4-6 week lead time!


Feb 03, 2017 at 02:56 PM
BastianK
Offline
• • •
Upload & Sell: Off
p.41 #19 · p.41 #19 · Front-End Filter Improves Corner Smearing


sebboh wrote:
sweet!

any idea if it corrects the mid distance field curvature for narrow dof shots as well as it does for the zm 35/1.4?


Did not check yet, but is already on my to do list. And I would be very suprised if it didn't help :-)



Feb 03, 2017 at 02:56 PM
BastianK
Offline
• • •
Upload & Sell: Off
p.41 #20 · p.41 #20 · Front-End Filter Improves Corner Smearing


rhawidantas wrote:
Hi Bastian,

Thanks for spending the time with the tests.

I have to say I am a bit overwhelmed by the amount of info in this thread on where to buy and how assemble the lens for the Voigt 35mm 1.7.

Will you guys be writing a blog post on where to buy the material and if not would be so kind in condensing in one post?

thanks once again,
Rhawi Dantas

Done already: https://phillipreeve.net/blog/rangefinder-wide-angle-lenses-on-a7-cameras-problems-and-solutions/

The correct description of the filter you need and how to attach the filter is included,
but I will add some more info on the two manufacturers (Optosigma and Eksma Optics).



Feb 03, 2017 at 03:02 PM
1       2       3              40      
41
       42              104       105       end




FM Forums | Sony Forum | Join Upload & Sell

1       2       3              40      
41
       42              104       105       end
    
 

You are not logged in. Login or Register

Username       Or Reset password



This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.