Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-27-2013, 08:48 AM   #16
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
Testing 67 lenses on the 645D is like testing FF 35mm lenses on and APS-C. You don't see what the rest of the lens does.

05-27-2013, 09:21 AM   #17
Senior Member
Paul MaudDib's Avatar

Join Date: Jul 2009
Location: Michigan
Posts: 292
That's kind of the point - you are shooting the sharpest, best corrected part of the lens. Who cares what the rest of the lens is doing? If you can actually see it, then you will have a larger sensor and you will be fine (ala 645D). If the center is sharp, you're golden.

I was citing the 645D because it's a similar setup to a really high-end full frame sensor like a D800 (the OP asked about it working on a new full frame sensor), but If you don't like the 645D test I guess you can look at the test on the Canon 5D Mark II, where the P67 lenses are also out-resolving the sensor. To head this goalpost-moving off at the pass, yes, if you put P67 lenses on the Pentax Q, you will have poor results, but more due to diffraction limits of the tiny tiny sensor than any fault of the lens.

The bigger problem is the focal length and speed. A 75mm lens is a 75mm lens no matter what format, so the OP would have an array of long-ish glass if he wanted to use them on his K-01 or on a FF DSLR. The widest rectilinear lens is the 45mm f/4, the absolute widest you could do is the fisheye 35mm (one of the poorer lens in the line). These are not particularly fast lenses. On the other hand there are some longer fast lenses that are probably quite good for sports or portraits or what have you, like the 105/2.4 or the 150/2.8 or 165/2.8. The difference in focal length will be much less pronounced on a 645 (particular the film models), where 75mm is a normal lens. I believe Pentax made auto-aperture adapters to allow full automatic functionality. All P67 lenses are manual-focus, however.

Last edited by Paul MaudDib; 05-27-2013 at 09:27 AM.
05-27-2013, 10:40 AM   #18
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
QuoteOriginally posted by Paul MaudDib Quote
...
Which of the Pentax 67 lenses, specifically, do you have a problem with?
I don't see any of your 6x7 shots in the medium format threads. Do you shoot that camera? I have a good collection of Pentax 6x7 lenses. And between my 3 MF film cameras (500C/M and M7II) the Pentax is mostly now used now for its excellent 300mm M* ED lens. I don't have that telephoto in the other cameras. The M7II wins out for me for a walking around camera and its really excellent wide 43mm it has. The 500C/M wins out for times when I need versatility with its hot-swapping backs and when I practice highlight compression. And the Pentax 6x7 picks up the remainder.
05-27-2013, 11:06 PM   #19
Senior Member
Paul MaudDib's Avatar

Join Date: Jul 2009
Location: Michigan
Posts: 292
Yes, I have a P67/.MLU kit with the 55/4, 75/4.5, 105/2.4, and 150/2.8.

Here is an example of one the SMC-T 6x7 105/2.4 wide open on Provia:




That's wide open and slow, handheld with MLU, and the slide is quite sharp (individual bugs can be seen in the scan). I have a M7 but I can't decide between the wides and can't afford them anyway. I picked up my P67 system for about $400 plus some upgrades (MLU body and split prism screen).

I tried a 45mm for my P67 at one point and it was not for me. I can't handle that much foreshortening and come out with interesting composition, so superwides are not a priority for me. Also, 10 shots is not a horrible burden for me in most situations. If I need something within 10 shots and latitude won't handle it, I probably am carrying an XA or a Stylus Epic or something as a backup. The 300/4 EDIF is reputed to be quite good and I'd like to try one for astrophotography, if I can afford it someday.


Last edited by Paul MaudDib; 05-27-2013 at 11:21 PM.
05-27-2013, 11:54 PM   #20
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
QuoteOriginally posted by Paul MaudDib Quote
Yes, I have a P67/.MLU kit with the 55/4, 75/4.5, 105/2.4, and 150/2.8.

Here is an example of one the SMC-T 6x7 105/2.4 wide open on Provia:
Nice shot and use of exposure and graduated darkening to deal with a wide open shot. Since there is a difference in 55/4 generations, saying 55/4 does not tell a fellow P67 shooter what lens you actually have, btw.
05-28-2013, 12:10 AM   #21
Senior Member
Paul MaudDib's Avatar

Join Date: Jul 2009
Location: Michigan
Posts: 292
QuoteOriginally posted by tuco Quote
Nice shot and use of exposure and graduated darkening to deal with a wide open shot. Since there is a difference in 55/4 generations, saying 55/4 does not tell a fellow P67 shooter what lens you actually have, btw.
The P67 55/4, late model, as I mentioned upthread. Definitely one of the best lenses I've used on any format, period. Remaining sharp enough out to the mid and corners wide open under any conditions (close up, etc) is not an easy task. The 55/4 can do it, the 105 is pretty sharp for what it is (a very fast double-gauss lens), sharp in the center and reasonably sharp in the edges. The 75/4.5 is slow but develops a lot of resolution right from the getgo, particularly in the center. However, the center is really the thing the sensor sees, right? You don't see what the rest of the lens does?

I imagine that adapted lenses would perform very well on a FF DSLR, if one ever gets released.

Last edited by Paul MaudDib; 05-28-2013 at 07:11 AM.
05-28-2013, 12:19 AM   #22
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
QuoteOriginally posted by Paul MaudDib Quote
The P67 55/4, late model. Definitely one of the best lenses I've used on any format, period. Remaining sharp enough out to the mid and corners wide open under any conditions (close up, etc) is not an easy task. However, the center is really the thing the sensor sees, right? You don't see what the rest of the lens does?
Yes.

You can find good uses for the 45mm even if that wide is not your style. Just look at its DOF scale. Getting DOF one might have taken for granted on their 35mm camera is often more of a challenge on this camera. The 45mm can come to the rescue sometimes. It's handy to have just in case.
05-28-2013, 03:39 AM   #23
Veteran Member
Silent Street's Avatar

Join Date: Nov 2011
Location: Geelong & Richmond, Vic AUS
Posts: 538
The 45mm f4 is my ultimate prime. I do have the 55mm, but my compositions make use of scale and perspective, chiefly in rainforests. It's chiefly a hyperfocal lens and equal in performance to the 55mm — both are used often by the 45mm is the go-to prime. My only gripe with the 45mm and 55mm is they are hard to focus in low light, and low light is everywhere in rainforests. WIth a polariser used in 99% of photography I have to remove it, focus precisely then refit the POL. This is a small price to pay though the the unimpeachable performance of such a stellar lens.

05-28-2013, 10:07 AM   #24
Senior Member




Join Date: Nov 2008
Photos: Gallery
Posts: 241
My 67 to K mount adapter came today. It is the Fotodiox version with tripod mount. I will be using it on my K-01 for among other things, astrophotography. I will be testing it on the newest 45, 55, 105, and 200 as well as the 75, 200, and 300 SMC Takumars. I will be checking wide-open performance using the infinitely small pinpoints of starlight as the test objects. I hope to post a review in the near future for those interested.

I have shot the 67 system for astrophotography for years and it excels even today. Being able to use my existing line of lenses with the K-01 will be a boon for me if the performance is what I expect. I'm expecting the 55,75 and 200 to be the best performers here. Just a hunch.

We'll find out starting tonight, which is looking to be clear.

If a lens can pass the star test it should be able to render nicely just about anything if sharpness is your thing, and with astrophotography it is just that.

Cheers !
06-01-2013, 05:17 AM - 1 Like   #25
Senior Member




Join Date: Nov 2008
Photos: Gallery
Posts: 241
A quick follow up. With the Fotodiox adapter all my 67 glass was able to be focussed at infinity and a preliminary star test revealed that while all the lenses did a good job in daylight, problems did occur on the cropped sensor with star images when lenses were utilized at full aperture. The results from my copies of the lenses revealed that my 50mm 1.7 SMC Pentax A surpassed the venerable SMC 67 55mm at equal apertures. The 105 and 165 lenses had a moderate amount of CA wide open, but was tamed by f/4.8 to f/5.6.

The stunner of all the lenses seemed to be the 75/4.5 Takumar. Wide open it was simply incredible, yielding pinpoints across the frame wide open with virtually no CA. This is also the result found on its 35mm brethren, the 35/3.5 Takumar.

The 200 looked fine, but focus is critical at f/4 and I will need more tests. It looks to be a good performer with lower CA than the 105 and 165.

I hope to have a thorough test on all these lenses before the end of summer and report my findings here on Pentax Forums.

While sharpness is not everything, bokeh is also consideration. The 105 at 2.4 is stellar in this area.

Morning Dew | Flickr - Photo Sharing!

Peace.
06-09-2013, 01:20 PM   #26
Pentaxian




Join Date: Feb 2009
Location: Arizona
Posts: 904
I have long suspected that the 75 Takumar could be the sharpest lens in the lineup. Your comment supports that impression. The 165 f/2.8 is a bit long for a Double Gauss design and I have questioned that idea by Pentax. The newer 165 (LS) uses the same design as the 200 Pentax and my copy seems to be very sharp. Their Ernostar design is better suited to that focal length.
11-03-2013, 05:32 AM   #27
Senior Member




Join Date: Nov 2008
Photos: Gallery
Posts: 241
Sorry to dig up an aging thread, but I had just been shooting my 67 glass on my K-01 and found that I was getting really good results. A tour through the woods with the 105mm/2.4 wide open was great. Once focused properly, it was razor sharp.





Likewise, the 75mm/4.5 is amazingly sharp wide open.






Compared with my other 35mm lenses these two lenses are on par or better with the best I own.
11-03-2013, 04:37 PM   #28
Pentaxian




Join Date: Feb 2009
Location: Arizona
Posts: 904
In case some have not seen the cross section for the 75mm f/4.5. Here it is.
Attached Images
 
11-03-2013, 10:41 PM   #29
Veteran Member
Silent Street's Avatar

Join Date: Nov 2011
Location: Geelong & Richmond, Vic AUS
Posts: 538
QuoteOriginally posted by desertscape Quote
In case some have not seen the cross section for the 75mm f/4.5. Here it is.
And the 75mm f2.8 ASPH.?
11-04-2013, 11:40 AM   #30
Pentaxian




Join Date: Feb 2009
Location: Arizona
Posts: 904
I have never seen the cross section of the 75 AL published. As an optics geek, I did take a guess at what is most likely inside that lens.
Attached Images
 
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, lenses, medium format, pentax, view
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pentax Medium Format Resources: 645 & 6x7 Cameras and Lenses, 645 & 6x7 Accessories Adam Pentax Medium Format 9 02-12-2017 03:38 AM
6x7 lenses on K-5 DeadJohn Pentax SLR Lens Discussion 12 04-25-2013 06:36 PM
Lens adapter to use non Pentax lenses on 6x7 Surlysteve Pentax Medium Format 8 03-12-2012 06:30 AM
6x7 Lenses on 645n & Stop-down Metering Trouble Dubesor Pentax Medium Format 4 02-04-2012 07:03 PM



All times are GMT -7. The time now is 11:22 AM. | 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