Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-24-2013, 04:37 PM   #1
Senior Member




Join Date: Aug 2013
Photos: Albums
Posts: 131
HD means higher MTF?

So with all the HD lenses that is now being offered, does it mean that the MTF is higher?
And if placed on full frame camera, after cropping the picture would still produce sharp images?
Hmmmm.... in doubt, but need to check with you guys first before i jump into HD DA15mm...
with 49mm Lee filters are possible?
So much question, need to know or my investment in it are all wasted....

10-24-2013, 05:12 PM - 1 Like   #2
Veteran Member




Join Date: Oct 2013
Posts: 402
I'd be curious as to what these lenses would yield on film. Wondering if the focal plane is the same.
10-24-2013, 05:15 PM - 1 Like   #3
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,430
QuoteOriginally posted by choong_dc Quote
So with all the HD lenses that is now being offered, does it mean that the MTF is higher?
No idea, and we likely won't until someone does a test.
QuoteOriginally posted by choong_dc Quote
And if placed on full frame camera, after cropping the picture would still produce sharp images?
AFAIK all of the HD lenses are for APS-C, so you would get vignetting to some degree, although some of the limiteds are reported to be able to cover the FF image circle. But to your question, since the optics AFAIK are the same as the SMC versions, just the coatings changing and the rounded blades, then there should be no difference in edge sharpness versus the SMC version. As to how they would work on a mythical FF camera? Who can tell until there is such a thing?
10-24-2013, 05:16 PM   #4
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,430
QuoteOriginally posted by OldNoob Quote
Wondering if the focal plane is the same.
If you mean the registration distance then it has to be the same. It's still a K-mount lens so distance to focal plane remains the same.

10-24-2013, 05:17 PM   #5
Senior Member




Join Date: Aug 2013
Photos: Albums
Posts: 131
Original Poster
On film?!!! I SALUTE you!!!
Let me check my current knowledge [might be wrong stuff kept in it]... Due to the HD DAs' being built for APSC crop sensors, would that cause heavy vignetting around your image with a 35mm [I might be ignorant about this-judgment be damned ]?

Last edited by choong_dc; 10-24-2013 at 05:22 PM.
10-24-2013, 05:23 PM   #6
Veteran Member




Join Date: Feb 2012
Location: Fredericton, New Brunswick
Photos: Gallery
Posts: 631
As far as the new coatings increasing MTF results? In theory? No. If the lighting is perfect, it should remain the same. In real life situations though, probably a better performer due to lower reflective properties.

The DA40 and DA70 Ltd lenses are FF compatible. The DA35 Macro is as well, to an extent. (Severe Vignetting @1:1 ratio, lessening by F8, but always being clearly there.)
10-24-2013, 05:25 PM   #7
Veteran Member




Join Date: Oct 2013
Posts: 402
i mean obviously there would be need of cropping, but it would be nice to drop in a roll of Fuji Reala 100 and test some of these HD lenses to see if they are truly flat, and don't have a Focal plane tilt, that some DSLRs compensate for.
10-24-2013, 06:06 PM   #8
Veteran Member




Join Date: May 2011
Location: Southern California
Photos: Albums
Posts: 4,082
QuoteOriginally posted by Eulogy Quote
As far as the new coatings increasing MTF results? In theory? No. If the lighting is perfect, it should remain the same. In real life situations though, probably a better performer due to lower reflective properties.

The DA40 and DA70 Ltd lenses are FF compatible. The DA35 Macro is as well, to an extent. (Severe Vignetting @1:1 ratio, lessening by F8, but always being clearly there.)
The DA70 is only compatible at f5.6, still only a minor crop would be needed.

OP,

The DA15 certainly will vignette heavily. You can buy the Samyang 14mm/2.8 for a full frame lens, but mounting filters is an expensive, or custom, proposition.

10-24-2013, 06:08 PM - 1 Like   #9
Veteran Member




Join Date: May 2011
Location: Southern California
Photos: Albums
Posts: 4,082
QuoteOriginally posted by OldNoob Quote
i mean obviously there would be need of cropping, but it would be nice to drop in a roll of Fuji Reala 100 and test some of these HD lenses to see if they are truly flat, and don't have a Focal plane tilt, that some DSLRs compensate for.
There is a thread on this forum with test shots from several Pentax lenses, on film.

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/31629-da-lens-...ts-thread.html

SMC Pentax-DA primes...
DA 14mm F2.8: - (clawhammer)
DA 15mm F4.0: - (Zav)
DA 21mm F3.2 Limited: - (Boris Liberman)
DA 35mm F2.4 AL: +++ (aurele ;like FA35/2.0 and no vignetting) (frank)
DA 35mm F2.8 Limited Macro: 0 (ryno), + (@ 1.15 crop)
DA 40mm F2.8 Limited: +
DA* 55mm F1.4 SDM: +++ (aurele)
DA 70mm F2.4 Limited: +
D FA Macro 100mm F2.8 WR: +++ (officially specified FF by Pentax)
DA* 200mm F2.8 ED [IF] SDM: +++? (common belief, but is it true?)
DA* 300mm F4 ED [IF] SDM: ++ (officially rated "designed for FF" by Pentax patent US7715116)
SMC Pentax-DA zooms...
DA 10-17mm F3.5-4.5 Fish-Eye ED [IF]: FE, see #59, #61, #94. 10mm: heavy vignette / 14mm: almost no vignette / 17mm ++ (Reps, froeschle, Gooshin)
DA 12-24mm F4 ED AL [IF]: - (below 16mm, xitek.com), o (at 18mm, architorture), + (at 20mm, architorture), ++ (at 24mm, architorture)
DA 16-45mm F4: - (below 21mm, Nesster)
DA* 16-50mm F2.8 ED AL [IF] SDM: - (xitek.com)
DA 17-70mm F4 AL [IF] SDM: - (KjetilH)
DA 18-55mm F3.5-5.6 AL: - (at 18mm, Spongefingers; below 23mm, xitek.com)
DA 18-55mm F3.5-5.6 AL II: missing
DA 18-250mm F3.5-6.3 ED AL [IF]: - (xitek.com)
DA 50-200mm ED: -
DA* 50-135mm F2.8 ED [IF] SDM: - (elho_cid)
DA* 60-250mm F4 ED [IF] SDM: ++ (officially rated "designed for FF" by Pentax patent US7489452) probably good on full frame but evaluation still missing; ++ is a temorary rating)
DA 55-300mm F4-5.8 ED: 0 (+, ++ at tele end, viking79)
Sigma K mount DC...
Sigma 18-200mm f/3.5-6.3 DC: -
Sigma 10-20mm f/4-5.6 DC: - (below 14mm, Gooshin)
...
Tamron K mount Di-II...
...
Overall rating scale:
+++: no significant difference between APS-C and FF corners
++: difference but usable at full aperture with a small loss in corner IQ only
+: usable staring at f/4~f/5.6, with no or a small loss in corner IQ only
o: usable at f/11 or with big loss in corner IQ only
-: not usable


Read more at: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/31629-da-lens-...#ixzz2igwg8lpo
10-24-2013, 06:42 PM   #10
Senior Member




Join Date: Aug 2013
Photos: Albums
Posts: 131
Original Poster
Great!!!! Now to look for a 24mm f2.8 manual lens for landscape so that it'll fit a FF Pentax in future... finger all crossed!!!
10-24-2013, 07:13 PM   #11
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,467
QuoteOriginally posted by choong_dc Quote
Great!!!! Now to look for a 24mm f2.8 manual lens for landscape so that it'll fit a FF Pentax in future... finger all crossed!!!
Find yourself a Tamron 24/2.5 (01B, Adaptall-2) and you are set!


Steve
10-25-2013, 04:56 AM   #12
Pentaxian




Join Date: Nov 2011
Photos: Gallery | Albums
Posts: 3,655
QuoteOriginally posted by choong_dc Quote
Great!!!! Now to look for a 24mm f2.8 manual lens for landscape so that it'll fit a FF Pentax in future... finger all crossed!!!
I've been well satisfied with the K24/2.8.
It's not always quite as sharp at the edges as some third-party lenses,
but controls flare well, and renders nicely.
10-25-2013, 07:18 PM   #13
Loyal Site Supporter




Join Date: Apr 2010
Location: Tennessee
Posts: 5,550
HD PENTAX-DA 15mm f/4 ED AL Limited Lens Review

This is the first review that I know of for the HD DA LTD glass.
10-25-2013, 07:36 PM   #14
Pentaxian
Digitalis's Avatar

Join Date: Mar 2009
Location: Adelaide.
Posts: 8,612
QuoteOriginally posted by choong_dc Quote
after cropping the picture would still produce sharp images?
Let me get this straight..you are going to use a full frame camera with an APS-C lens and crop the image afterwards...you would save time by sticking with an APS-C camera then.


QuoteOriginally posted by OldNoob Quote
test some of these HD lenses to see if they are truly flat, and don't have a Focal plane tilt, that some DSLRs compensate for.
If a lens has a tilt in the imaging plane then it will perform poorly on film and digital, no camera can compensate for a de-centred lens. There are very few lenses with a perfectly flat focus field, nearly all of them are macro lenses and are very expensive.

QuoteOriginally posted by choong_dc Quote
with 49mm Lee filters are possible?
With the filter holder and a few Lee 100x150mm filters on the front of a tiny lens like the DA15 the appearance is rather comical - i'm speaking from experience here.

QuoteOriginally posted by choong_dc Quote
So with all the HD lenses that is now being offered, does it mean that the MTF is higher?
No. HD is just a re-branding of SMC coatings.
10-25-2013, 10:50 PM   #15
Senior Member




Join Date: Aug 2013
Photos: Albums
Posts: 131
Original Poster
Well if it means by using the DA15mm on a future pentax FF DSLR which i would get a 24mmFL i'd be happy coz its HD...but now you said it was just rebranding of SMC coatings [I'm turned off]... my frustration and disappointment was further re-enforced when i tested the HD lenses from my friends K5 and made comparison to his non HD DA limited... no difference... Thinking of a 12-24 and an Fish Eye... also i does not look comical with a 77mm filter mount :P
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!
hd, k-mount, pentax lens, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
MTF program mode, w00t ! spystyle Photographic Technique 7 07-16-2013 02:53 PM
Is there an MTF setting? guavaboy Pentax K-30 & K-50 4 07-03-2013 10:21 PM
A question for the MTF guys. normhead Pentax DSLR Discussion 3 04-08-2013 05:46 AM
Hot K-5 means louder shutter? rawr Pentax K-5 9 10-24-2012 01:10 AM
Where do I find MTF graphs? micmac Pentax SLR Lens Discussion 7 07-19-2012 07:44 AM



All times are GMT -7. The time now is 04:32 PM. | 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