Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-02-2013, 09:00 AM   #76
Site Supporter




Join Date: Jan 2010
Location: Michigan
Photos: Gallery
Posts: 2,072
Halloween night, I used the K-01 with a Vivitar f/2 28mm cfwa, a manual lens, so in Manual mode, f/2 to f/4 , manually focussed by the focus peaking.
Also the ist ds with the 18~55mm kit lens in AF and Av mode, iso 400 and f/8 with its internal flash deployed.
The shots were difficult for me , either low light or with flash, the kids were moving fast etc.

Anyway the shots out of the old ist ds with the 18~55mm kit lens and flash were almost invariably far sharper and better exposed and better color balanced that the manual ones I took on the K-01.
Most of the istds / 18~55 shots are even sharp enough at 100% zoom, so lens quality is not an issue for me, viewing on a 22 inch monitor.

I have done tripod tests comparing the 18 ~55 with the 50mm lenses here, and the 18 ~55mm kit lens shows edge sharpness falloff, and worse flare into sun on test shots but that doesn't seem to be such an issue on real photos.

The problem I had with the manual lens at below f/4, and the motion, the K-01 focus peaking does not have enough resolution for me to pick focus on a face, even if the zoom focus is used. If I put the 18~55mm kit lens on the K-01, the problem is it takes too long to AF focus on the moving subjects.

11-02-2013, 09:18 AM   #77
Veteran Member




Join Date: Oct 2013
Posts: 402
QuoteOriginally posted by altopiet Quote
I see quite a few people saying that you should just find the sweet spot, that might be perhaps, say @35mm, or something like that, for someone else perhaps another setting... My problem is that the lens is supposed to give passable images all over. If I can only get passable images at a certain focal length and aperture, I might just as well get a prime fot that purpose. That said, I'll take my WR for another spin this weekend, just to see if perhaps I missed something the other times��
yep indeed, i agree. The lens has only limited sweetspot somewhere between 28 and 45mm at f/7.1 , my experiance with the WR anyway. If you try f/5.6 at any focal setting it seems blurry at 100%
11-02-2013, 09:32 AM   #78
Site Supporter




Join Date: Jan 2010
Location: Michigan
Photos: Gallery
Posts: 2,072
QuoteOriginally posted by OldNoob Quote
If you try f/5.6 at any focal setting it seems blurry at 100%
Here is a test shot, full resolution jpg of it at f/5.6
You can go up to 100% on your monitor and see the blur at the sides, actually fairly good compared to my experience with other zooms i have tested here.
(Of course, I don't have any $1000 zooms here !)
https://app.box.com/s/bo8v50zqygjfq6m82nce

Part of the exif for that:
Software : K-01 Ver 1.02
Modify Date : 2012:09:19 09:58:53
Artist :
Y Cb Cr Positioning : Co-sited
Copyright :
Exposure Time : 1/160
F Number : 5.6
Exposure Program : Manual
ISO : 400
Exif Version : 0230
Date/Time Original : 2012:09:19 09:58:53
Create Date : 2012:09:19 09:58:53
Components Configuration : YCbCr
Exposure Compensation : 0
Metering Mode : Spot
11-02-2013, 11:48 AM   #79
Pentaxian
kh1234567890's Avatar

Join Date: Sep 2010
Location: Manchester, UK
Photos: Gallery
Posts: 2,327
QuoteOriginally posted by wombat2go Quote
Here is a test shot, full resolution jpg of it at f/5.6
You can go up to 100% on your monitor and see the blur at the sides, actually fairly good compared to my experience with other zooms i have tested here.
(Of course, I don't have any $1000 zooms here !)
That's about right for 50mm f5.6. Here is a brick wall one from the DA18-55 WR at 55mm f5.6. Full size on Flickr.




11-02-2013, 12:14 PM   #80
Veteran Member
Joel B's Avatar

Join Date: Aug 2013
Location: Des Moines, Iowa
Photos: Albums
Posts: 2,336
the only reason my copy doesn't get used more is 55 just isn't long enough for what I'm doing. My smc-F 35-80 actually gets a lot more play, partly because I think it looks cool with a rubber hood on it! My copy of the 18-55 is older from around 2008. I don't know if mfg dates have anything to do with quality, But mine has always done well.
Joel
11-02-2013, 09:40 PM   #81
Pentaxian
Sagitta's Avatar

Join Date: Feb 2011
Location: Maine
Photos: Gallery
Posts: 2,912
QuoteOriginally posted by Joel B Quote
the only reason my copy doesn't get used more is 55 just isn't long enough for what I'm doing. My smc-F 35-80 actually gets a lot more play, partly because I think it looks cool with a rubber hood on it! My copy of the 18-55 is older from around 2008. I don't know if mfg dates have anything to do with quality, But mine has always done well.
Joel
This. My FA28-90 effectively shelved the 18-55, then my 10-20 put the nail in its coffin. I only use the 18-55 now if I really want to have some sort of play between 20 and 28mm, and I don't find that happening very often. When I do I'll usually just use the 10-20 or one of the numerous 28mm-whatever lenses I own.
11-02-2013, 10:37 PM   #82
Veteran Member




Join Date: Jan 2010
Location: Southern England
Posts: 495
As others have mentioned, the softness could well be caused by the filter. Just take a look at what a cheapo filter can do:

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/124056-impa...uv-filter.html

LensRentals.com - Good Times with Bad Filters

(Apologies, as I posted these links in another thread a few days ago.)

Assuming the filter that was used for the test shot was of the cheapo variety, try some test shots without filter. If you feel you want to protect your lenses with filters, then get something decent (and multicoated) from Marumi or Hoya.
11-05-2013, 04:31 PM   #83
Senior Member




Join Date: Dec 2011
Posts: 254
Maybe I had really bad copies but I never got one that was good at 55mm f5.6, that test shot above isn't bad better than anything I got, usable though.
Still makes you wonder how lenses can vary that much.

All the DAL ones I tried were pretty poor

11-18-2013, 08:12 PM - 1 Like   #84
Veteran Member




Join Date: Oct 2013
Posts: 402
I realize this is an old post, but after some testing with my 18-55mm , i have been able to reproduce the OP's problem And yep it's Focusing Beyond Infinity. I have gotten my k-30 to do this several times when focusing on distant landscapes. the most consistant example of FBI is taking shots of the Moon, at any exposure setting it FBI'ed consistently. Correction with manual focus was necessary. Yet while focusing on objects withing a hundred feet it seems fine.
11-19-2013, 04:39 AM   #85
Veteran Member
Joel B's Avatar

Join Date: Aug 2013
Location: Des Moines, Iowa
Photos: Albums
Posts: 2,336
QuoteOriginally posted by OldNoob Quote
I realize this is an old post, but after some testing with my 18-55mm , i have been able to reproduce the OP's problem And yep it's Focusing Beyond Infinity. I have gotten my k-30 to do this several times when focusing on distant landscapes. the most consistant example of FBI is taking shots of the Moon, at any exposure setting it FBI'ed consistently. Correction with manual focus was necessary. Yet while focusing on objects withing a hundred feet it seems fine.
Kudos to OldNoob for working that problem through! And without an optical viewfinder it's hard to catch until too late.My old Sears lens focuses past infinity but it's the only one for me.
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, pentax da, pentax lens, sharpness, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax DA L 18-55mm kit lens 6BQ5 Sold Items 4 10-15-2013 11:53 AM
For Sale - Sold: Pentax K100D, Pentax-DA L 55-300mm, Pentax-DA L 18-55mm sjwoo Sold Items 5 05-21-2013 08:28 AM
For Sale - Sold: PENTAX DA-L 18-55mm (PRICE DROP!) TOUGEFC Sold Items 6 06-08-2012 05:00 AM
For Sale - Sold: Pentax K-x + DA-L 18-55mm, DA-L 55-300mm Kit + Pentax Lens Hoods (US) (US) aerodynamics Sold Items 5 10-13-2010 09:38 PM
For Sale - Sold: Pentax DA 18-55mm L + 50-200mm L bundle lens Smashed Pie Sold Items 2 11-18-2009 02:16 PM



All times are GMT -7. The time now is 05:00 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