Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-09-2012, 09:51 AM   #1
Veteran Member




Join Date: Jan 2012
Posts: 691
DA35/2.4 ~ What about a 16 or 17 wide angle version?

Is it possible to make a 16 or 17 2.4 around the size of 35/2.4?

I am so going to get the DA50/1.8.

03-09-2012, 10:10 AM   #2
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
At f/2.4, the answer is NO, at least not for APS-C. Well, maybe it would be *possible*, but the optics wouldn't be real good. Wide lenses can be 1) small and fairly slow, or 2) big and fairly fast, or 3) have crappy optics. Compare the big DA14/2.8, the small DA15/4, and the tiny Fisheye Takumar 18/11.

For a camera with a smaller format than APS-C, it's no problem. Short fast lenses are common and fairly cheap, for small enough formats (like video). I have a lightweight 15-25mm f/1.2 zoom that cost me all of ONE BUCK! Only problem is, it's for a Super-8 camera. Doesn't work on my K20D, nope.

How-to build a fast wide lens: 1) take a FA50/1.4; 2) mount a 0.25x wide screw-on adapter on its front, giving a 13/1.4 optic; 3) ignore the distortions and aberrations and bulk and snide sneers. Better yet, just save up for the DA14 or DA15 I mentioned above. Or if you don't mind fishiness, get a Zenitar 16/2.8.

Last edited by RioRico; 03-09-2012 at 10:15 AM.
03-09-2012, 10:43 AM   #3
Veteran Member
ironlionzion's Avatar

Join Date: Dec 2010
Location: Dallas, TX
Posts: 409
With the high iso capabilities of dslrs today, it'd be kind of cool and reasonable to make a really compact wide angle small aperture lens like a 16mm f/8...probably won't happen though...
03-09-2012, 10:51 AM   #4
Pentaxian




Join Date: Jun 2011
Location: NJ
Photos: Gallery
Posts: 4,882
QuoteOriginally posted by ironlionzion Quote
With the high iso capabilities of dslrs today, it'd be kind of cool and reasonable to make a really compact wide angle small aperture lens like a 16mm f/8...probably won't happen though...
There's already the DA 15 f/4... and at f/8 you're already just one stop away from diffraction on an APS-C sized sensor.

And as good as the current crop of sensors are, there's still no substitute for low ISO when it comes to noise, sharpness & DR.

03-09-2012, 10:57 AM   #5
Veteran Member
ironlionzion's Avatar

Join Date: Dec 2010
Location: Dallas, TX
Posts: 409
QuoteOriginally posted by luftfluss Quote
f/8 you're already just one stop away from diffraction on an APS-C sized sensor
true, didn't think about that.
03-09-2012, 11:20 AM   #6
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
A note on diffraction limit: On an APS-C-size frame, the limit is around f/9. But that really only matters with pixel-peeped tripodded mirror-locked-up images. For handeld shots, even with SR on, we don't really notice the effects until around f/22 on a large display, beyond that with smaller images. Anyone with an 18-55 kit lens can check it out. At 55mm its f-stop range is f/5.6-40. Shoot a set of handheld test shots at f/8-11-16-22-32-40, then display them at moderate size|resolution, not at 100%. They will follow the old rule: Almost any picture looks good if it's small enough!
03-09-2012, 11:42 AM   #7
Emperor and Senpai
VoiceOfReason's Avatar

Join Date: Jun 2010
Location: Nashville, IN
Posts: 5,420
I have a Sigma 20 f/1.8 and that thing is huge. I can only imagine how much bigger if it were wider AND faster. 100+mm filters anyone?
03-09-2012, 11:43 AM   #8
Senior Member




Join Date: May 2010
Photos: Gallery
Posts: 208
To (sort of) respond to the initial quesiton, though, I wonder whether the XS series will include any small wide primes? Personally, I'm hoping for a 24/2, but an 18/2.8 would also be of interest. Of course, those lenses might not be mirrorbox-friendly . . .

03-09-2012, 12:24 PM   #9
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
I suspect we have a parallel with paranormality. If water-witching for petroleum worked, energy firms would sponsor appropriate training programs, instead of hiring those expensive geophysicists. If good small fast wide cost-effective lenses for APS-C cameras *could* be built, they *would* be built. What is the smallest-fastest-widest-cheapest glass for the NEX? That could hint at the limits for the XS line.
03-09-2012, 12:33 PM   #10
Pentaxian
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
I'd like a 10mm F0.95 with a tripod mount, kthx
03-09-2012, 12:34 PM   #11
Senior Member




Join Date: May 2010
Photos: Gallery
Posts: 208
QuoteOriginally posted by RioRico Quote
I suspect we have a parallel with paranormality. If water-witching for petroleum worked, energy firms would sponsor appropriate training programs, instead of hiring those expensive geophysicists. If good small fast wide cost-effective lenses for APS-C cameras *could* be built, they *would* be built. What is the smallest-fastest-widest-cheapest glass for the NEX? That could hint at the limits for the XS line.
That would be 16/2.8 . So 18/2.8 or 24/2 should not be a problem . . .
03-11-2012, 09:29 AM   #12
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,107
Interesting question and the previous postings have all provided excellent responses. In the past, particularly full frame lenses, provide some answers. Carl Zeiss starting in the mid 70's and through 2005 had a professional line of cameras, Contax (and there is a Pentax story here but for another time). Their line of lenses all had a very similar look and feel (from the Porsche Design Group), plus they were as small as possible. Their line-up of lenses ran from 16mm to 300mm, so if you pay particular attention to the 25mm through the 85mm, they are all of a very similar physical size and weight - for the aperture of f2.8 (the f2, f1.4 lenses are all much larger). Take a look at this database (and slide the slider bar on the right hand side over to the right to get the physical dimensions)Now these lenses all contain great optics, excellent build, and perform wonderfully on today's digital cameras. Canon folks seek them out for these qualities (and they mount with a cheap inexpensive adapter).

However take a look at the wider end, from 21mm down to 15mm, the physical dimensions grow comparatively quite large and the front elements get quite big. This is just a real life example of what happens when the reality of optics meet the designers whim - optics wins out....

03-11-2012, 05:02 PM   #13
Veteran Member




Join Date: Jan 2012
Posts: 691
Original Poster
Browsing with Android I see no weight and size. But lenses optimize for apsc would be smaller yes? I am sure the next killer wide angle with small form factor would be for ko 1 utilizing the vast space between lens and sensor. With this kind of concept, I thought this would mean wr zoom (internal), prime and body as well. Ko 2 perhaps.
03-11-2012, 07:48 PM - 1 Like   #14
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
QuoteOriginally posted by lightbulb Quote
Browsing with Android I see no weight and size. But lenses optimize for apsc would be smaller yes? I am sure the next killer wide angle with small form factor would be for ko 1 utilizing the vast space between lens and sensor. With this kind of concept, I thought this would mean wr zoom (internal), prime and body as well. Ko 2 perhaps.
PK-AS-mount lenses that extend far into a mirrorless body will need some physical limiter so they can't be mistakenly mounted on our dSLRs. AFAIK we don't know yet if Pentax makes such protection for the K01 mount. If so, then some VERY flat primes and short zooms could be designed. I'll take a pancake 20-40/2.8, thanks. A "killer wide angle with small form factor" could maybe be built, or maybe not, but probably not much shorter than 16mm. Shorter (and faster) will probably be bigger. But we can hope, can't we?
03-11-2012, 08:26 PM   #15
Pentaxian
Jonathan Mac's Avatar

Join Date: Apr 2009
Location: Madrid, Spain
Posts: 4,361
Samsung have a 16mm f/2.4 lens which is small & apparently performs well (unlike the Sony 16mm f/2.8, which is just small). I see no reason why one couldn't be made for a K-mount, though the increased registration distance would mean it would have to be larger.
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!
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
Misc with the wide angle _riccardo_ Post Your Photos! 4 03-05-2012 01:37 AM
wide angle Conqueror Pentax SLR Lens Discussion 21 12-17-2011 09:49 PM
Which wide angle should I go with? iseeincolor Troubleshooting and Beginner Help 25 06-10-2011 06:10 PM
Pentax 10-16 mm wide angle ? lesmore49 Pentax News and Rumors 35 04-10-2010 06:34 AM
Tokinas version of the DA35 Macro blende8 Pentax SLR Lens Discussion 13 03-20-2007 06:55 AM



All times are GMT -7. The time now is 10:10 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