Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-17-2010, 06:48 AM   #31
Veteran Member
Abbazz's Avatar

Join Date: Nov 2006
Location: Myanmar
Posts: 510
QuoteOriginally posted by blende8 Quote
Ok, what do you mean by a "tack sharp picture"?
Below is a quick shot of my phone.
Sharp enough for me.
100% crop:
Thank you for taking the time to post this sample picture. It does indeed appear sharper than anything that I get from my second copy of this lens, but I find the longitudinal chromatic aberration in the 100% crop (green halo in the out of focus background and purple halo in the out of focus foreground) particularly annoying.

Most lenses appear sharper when used for close-up photography. It's better to judge sharpness on a picture taken at infinity. On both copies of the 20/1.8 that I tried, landscape pictures don't look good with mediocre sharpness and lots of chromatic aberrations.

Here are some comparison pictures taken this morning -- sorry but it was pouring, so I had to put the tripod in my garage to take these boring pictures. You can click on any of them to view it full size.

20/1.8 @ F/1.8:


20/1.8 @ F/2.0:


20/1.8 @ F/2.8:


20/1.8 @ F/4:


20/1.8 @ F/5.6:


24/1.8 @ F/1.8:


24/1.8 @ F/2.0:


24/1.8 @ F/2.8:


24/1.8 @ F/4:


24/1.8 @ F/5.6:


30/1.4 @ F/1.4:


30/1.4 @ F/1.8:


30/1.4 @ F/2.0:


30/1.4 @ F/2.8:


30/1.4 @ F/4:


30/1.4 @ F/5.6:


Cheers!

Abbazz


Last edited by Abbazz; 01-17-2010 at 07:06 AM.
01-17-2010, 07:29 AM   #32
Veteran Member
blende8's Avatar

Join Date: Feb 2007
Location: Bremen, Germany
Photos: Albums
Posts: 1,484
Boah Abbazz, that's bad! I agree.
One can see double images at the antenna and those glowing borders.
Not good!

This is definitely a bad copy of that lens.
Mine does not show this.
01-17-2010, 08:46 AM   #33
Veteran Member
pcarfan's Avatar

Join Date: Sep 2007
Location: Dayton, Ohio
Photos: Gallery | Albums
Posts: 2,958
Original Poster
@Abbazz and Wielnad,

Thank you for those sample images.

P.S: How do you link images like Abbazz has done where it goes to the full resolution when clicked on it...I know 'imgwide' doesn't do that..........
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!
f1.8, k-mount, pentax lens, sigma, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sigma 28mm f/1.8 and Sigma 30mm f/1.4: 3 Questions Biro Pentax SLR Lens Discussion 0 03-06-2010 03:12 PM
Sigma & Pentax Primes 15-30mm Christopher M.W.T Pentax SLR Lens Discussion 3 02-28-2010 05:50 PM
sigma 30mm vs. pentax 30mm jay legere Pentax SLR Lens Discussion 6 02-01-2008 04:15 PM



All times are GMT -7. The time now is 11:08 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