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Forum: Troubleshooting and Beginner Help 07-04-2020, 12:10 AM  
Extension tubes and aperture control.
Posted By jim.haase
Replies: 12
Views: 2,231
How does one control the aperture on lenses that do not have an aperture ring when using an extension tube. Does it default to the widest aperture which kind of defeats the purpose of photography using extension tubes - close focus with a wide depth of field.Thanks in advance for your input.
Forum: Sold Items 07-03-2020, 11:50 PM  
For Sale - Sold: SMC Pentax-D FA 100mm F2.8 Macro WR MORE Reduction in price - Shipping included !!
Posted By jim.haase
Replies: 30
Views: 5,263
Whats the lowest offer you would accept?
Forum: Troubleshooting and Beginner Help 03-28-2020, 01:23 PM  
Stuck aperture on Pentax DA 16-85
Posted By jim.haase
Replies: 14
Views: 1,170
Had the same problem. It happenned when I tripped and fell. Camera or lens did not hit the ground but I guess it jarred it enough the the aperture was stuck wide open. Sent it to Advance Camera in Portland and they repaired it for what I thought was a very reasonable price. I believe around $75.
Forum: Pentax SLR Lens Discussion 12-11-2019, 12:35 PM  
PENTAX-DA 12-24mm is now discontinued
Posted By jim.haase
Replies: 71
Views: 5,361
I had the 12-24 for a number of years. Thought its was a good lens and adequately sharp until I purchased the 11-18. The 11-18 is a far superior lens in both sharpness (center, corner and edge) and chromatic abberations. A little heavy but optically superior to the 12-24
Forum: Pentax SLR Lens Discussion 04-24-2019, 08:34 AM  
Supplentary lens protection plan
Posted By jim.haase
Replies: 4
Views: 888
Supplementary as in addition to the the manufacturers warrantee
Forum: Pentax SLR Lens Discussion 04-24-2019, 07:21 AM  
Supplentary lens protection plan
Posted By jim.haase
Replies: 4
Views: 888
Has anyone ever purchased the Square Trade protection plan that is sold by B and H? If you have, any experince(s) good or bad?

Thanks in advance for any info provided.

Jim
Forum: Pentax SLR Lens Discussion 04-23-2019, 02:37 PM  
De-centering test on new DA*11-18 f2.8 lens.
Posted By jim.haase
Replies: 7
Views: 1,296
I recently purchased the new DA*11-18 lens and decided that I would test for any de-centering. I have never done this before so with the help of the internet I found a process for performing the test.The following is the process I used, the camera and lens settings, and the results.

Settings
Camera - K3 mounted on tripod
Exposure - Manual (Spot metered on the center of target on first (center) exposure)
Focus - Manual
Shake reduction - Off
Aperture - 2.8
Focal Length - 11mm and 18mm
Shutter speed - As need for correct exposure
ISO - 100

Process
Set the focal length to 11 mm. Positioned camera so the target (building about 120 yards away with sign"FISH CAMP") was in the center of the view finder. Focused on the "FISH CAMP" sign and adjusted shutter speed for proper exposure. Turned on the Focus Clamp (neat option on this lens) to ensure focus did not change between exposures. Took the first exposure using a remote shutter release in the mirror lock up mode. Loosened the tripod ball head and moved the camera so the target was in the upper left of the viewfinder. Tightened the ball head and made the second exposure. Repeated this for the other three corners. Changed focal length to 18 mm and repeated the whole process.

The attached images are 100% crops of the images. The top is the 11mm set and the bottom the 18 mm set. These are straight out of the camera images with no adjustments made. The only thing I did was crop them and make a collage in photo shop of the two different focal lengths

My observations - Upper left is the softest wth the bottom right the sharpest (There was a significant wind so don't look at the trees). Appears to have a little more vignetting on the top corners as compared to the bottom corners (top corners are darker than bottom corners). There is a little chromatic aberration in all four corners but could easily be corrected. CA on the 12-24 is much worse.

Since I have never done a de-centering test before was this the correct process and if so is this an acceptable lens regarding focus de-centering? I believe it is but for the price of the lens I just wanted to get a second opinion. Even though you want it to be there is probably no perfect lens.
Forum: Site Suggestions and Help 04-23-2019, 01:00 PM  
Managing attachments
Posted By jim.haase
Replies: 7
Views: 850
Thanks Adam for your options. I went ahead and donated
Forum: Site Suggestions and Help 04-23-2019, 10:45 AM  
Managing attachments
Posted By jim.haase
Replies: 7
Views: 850
Got to that page but cannot find a way to delete attachments. Can view them but not delete them
Forum: Site Suggestions and Help 04-23-2019, 09:28 AM  
Managing attachments
Posted By jim.haase
Replies: 7
Views: 850
How do I delete attached photos. Have used up all of my attachment space and would like to add a couple of attachments.
Forum: Pentax SLR Lens Discussion 03-09-2019, 07:36 AM  
Da*11-18 2.8
Posted By jim.haase
Replies: 1
Views: 1,055
Has anyone tried out the new 11-18mm 2.8 lens yet and if so what are your impressions?
Forum: Monthly Photo Contests 10-16-2018, 12:00 AM  
Reflections
Posted By jim.haase
Replies: 2
Views: 461
Photo taken early morning at Lake Placids' Mirror Lake.
Forum: Monthly Photo Contests 07-10-2018, 06:01 AM  
Sendedalsmyrane
Posted By jim.haase
Replies: 21
Views: 858
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 06:00 AM  
Lysefjord
Posted By jim.haase
Replies: 27
Views: 1,155
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 06:00 AM  
Fjord of Light
Posted By jim.haase
Replies: 18
Views: 1,312
I would like to nominate this photo
Forum: Winners' Showcase 07-10-2018, 05:58 AM  
June, 2018 Third Place: Sunset on Castlebar River
Posted By jim.haase
Replies: 40
Views: 2,356
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 05:58 AM  
Barguzin river
Posted By jim.haase
Replies: 20
Views: 865
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 05:58 AM  
Vickery Creek
Posted By jim.haase
Replies: 28
Views: 1,110
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 05:57 AM  
Kaldbaksfjordur
Posted By jim.haase
Replies: 28
Views: 1,053
I would like to nominate this photo
Forum: Monthly Photo Contests 07-10-2018, 05:57 AM  
Bighorn River Canyon
Posted By jim.haase
Replies: 24
Views: 1,453
I would like to nominate this photo
Forum: Winners' Showcase 05-02-2018, 07:42 AM  
April, 2018 Third Place: Under The Falls
Posted By jim.haase
Replies: 65
Views: 3,019
I would like to nominate this photo
Forum: Winners' Showcase 05-01-2018, 09:44 PM  
May, 2018: Third Place: Old Man and His Dog
Posted By jim.haase
Replies: 83
Views: 4,642
Photo from a trip to Barcelona
Forum: Monthly Photo Contests 07-14-2017, 11:54 AM  
Bit of a Twist
Posted By jim.haase
Replies: 21
Views: 1,564
Nice pic
Forum: Monthly Photo Contests 07-13-2017, 08:30 PM  
Guardian Angel
Posted By jim.haase
Replies: 5
Views: 630
Glenwwod cemetery in Houston Texas
Forum: Post Your Photos! 11-20-2016, 12:05 AM  
Nature Schools in Session
Posted By jim.haase
Replies: 1
Views: 754
A pic I did a little experimenting with processing this image.
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