Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-27-2011, 09:43 PM   #1
New Member




Join Date: Dec 2011
Location: Sydney, Chatswood.
Posts: 10
Pentax 67 120mm soft focus lens

Likely most would use this for soft focus at the bigger f stops. How sharp though is it between f8-f22, can it be used for scenic photography as i like the size and weight of it. I noted one review on this site said very sharp above f8. Does this sound accurate?

Thanks

12-28-2011, 12:05 AM   #2
Pentaxian




Join Date: Jan 2010
Location: Vancouver, BC
Posts: 1,421
Most soft focus lenses are portrait lenses and as such they are sharp, flat field lenses. The soft focus usually only work at maximum aperture and the softness would start diminishing as the lens is stopped down and by f5.6-8, it would function as any sharp portrait focal length lens. If you already have it great, but if you are not a portrait shooter, there is no point in paying the premium for the soft effect.
12-28-2011, 04:46 AM   #3
Senior Member




Join Date: Jun 2010
Location: Hamburg
Posts: 267
what's the soft effect like? What does this lens achieve that the 100mm Macro or the 105mm doesn't?
12-28-2011, 08:36 AM   #4
Veteran Member




Join Date: Feb 2011
Photos: Gallery
Posts: 573
Soft Focus lenses have spherical aberration built in. They would cause a foggy glow. Oddly enough, soft focus lenses are very high resolution and so the spherical aberration does not blur detail.

12-28-2011, 04:25 PM   #5
New Member




Join Date: Dec 2011
Posts: 22
QuoteOriginally posted by Yamanobori Quote
Soft Focus lenses have spherical aberration built in. They would cause a foggy glow. Oddly enough, soft focus lenses are very high resolution and so the spherical aberration does not blur detail.
Thanks for answering my question before it was asked. "Sharp" is a relative term...I was about to check my copy of The Camera to see if there was a specific section on soft focus lenses.
12-28-2011, 05:26 PM   #6
Pentaxian




Join Date: Feb 2009
Location: Arizona
Posts: 868
Let's not misunderstand; the reason it is called "soft" is because the spherical aberration is left uncorrected. Marginal, zonal and paraxial rays all have a different focus and when stopped down, the marginal and zonal rays are truncated, leaving the paraxial rays to form the image. Using these rays reduces the spherical greatly and makes for a sharp image. Shot wide open it is soft.
12-28-2011, 05:58 PM   #7
Veteran Member




Join Date: Feb 2011
Photos: Gallery
Posts: 573
It is not soft wide open in that the resolving power is still excellent. You can get a lot of detail wide open from a soft-focus lens, but you are also getting a glow which lowers contrast and creates the halo/glow effect. I remember an article that showed a soft focus lens out resolving a normal one of similar focal length. Smearing grease on your lens or unfocusing it will not duplicate the image from a soft focus lens.
12-29-2011, 02:18 AM   #8
Senior Member




Join Date: Jun 2010
Location: Hamburg
Posts: 267
do any image examples exist? I'd like to see what you are talking about, esp. that "glow" effect.

12-29-2011, 08:37 AM   #9
Veteran Member




Join Date: Feb 2011
Photos: Gallery
Posts: 573
I did a google search and many of the examples are using a soft-focus filter, which is not the same thing. Personally, I have ever been into the soft-focus effect and have never owned one. This is one on Flickr, but the size is not really big enough to appreciate the image. Medium-format and large format soft focus lenses are nicer as they have special sieve aperture plates.

Soft Focus Test 5 | Flickr - Photo Sharing!
12-29-2011, 11:59 AM   #10
Senior Member




Join Date: Jun 2010
Location: Hamburg
Posts: 267
This is the effect? And you get this with the Pentax 120 soft lens at all apertures? Wow, ugly. What's the point in having this effect for portraits?
12-29-2011, 03:09 PM   #11
New Member




Join Date: Dec 2011
Posts: 22
That's a really strong softening effect, by my standards.

I own a couple of original silver prints of Greta Garbo, and - while I don't have documentation on the lens choice - they were obviously shot with either a soft focus lens or an exceptional soft focus technique. The effect is very subtle, but it's noticeable...it adds a smoldering glow to the highlights, almost a coronal feel, without blowing them out.
12-29-2011, 03:26 PM   #12
Veteran Member




Join Date: Feb 2011
Photos: Gallery
Posts: 573
QuoteOriginally posted by phonoline Quote
This is the effect? And you get this with the Pentax 120 soft lens at all apertures? Wow, ugly. What's the point in having this effect for portraits?
No, the spherical aberration is reduced as you stop down, at about f/11, the glow is mostly gone. In order to keep the glow and control exposure, really good soft focus lenses have a sieve aperture plate.

Well, you are just not going to fit in with the photographic trend of the turn of the 20th century.
12-29-2011, 03:41 PM   #13
Senior Member




Join Date: Jun 2010
Location: Hamburg
Posts: 267
your example just looks very photoshopped, maybe that's why I can't get warm with this effect. I'd like to see an acual picture taken with that Pentax lens to see if it is interesting/worth to purchase or not.
12-29-2011, 05:16 PM   #14
New Member




Join Date: Dec 2011
Location: Sydney, Chatswood.
Posts: 10
Original Poster
Thanks for the insight. I hear what you saying about the cost if not a portrait shooter, however the size and weight makes it a good option for backpacking.
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, focus, medium format
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Rare SMC Pentax 85mm F2.2 Soft Focus (US/CAN) ga-hing Sold Items 13 10-15-2010 03:33 PM
Soft focus on SMC Pentax-DA 18-55mm F3.5-5.6 AL WR khvatov Pentax SLR Lens Discussion 7 07-29-2010 05:47 AM
For Sale - Sold: SMC PENTAX-FA 1:2.8 28mm -SOFT FOCUS- tsiklop Sold Items 4 01-04-2010 09:52 AM
For Sale - Sold: SMC Pentax FA 85mm F2.8 Soft Focus Lens tsiklop Sold Items 8 12-26-2009 02:14 PM
For Sale - Sold: SMC Pentax-FA 28mm 2.8 SOFT FOCUS Lens tsiklop Sold Items 3 12-22-2009 09:37 AM



All times are GMT -7. The time now is 08:16 AM. | See also: NikonForums.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