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Forum: Pentax K-1 & K-1 II
08-12-2021, 08:23 AM
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I have no problems with my 58 AF-2 on my K-1. Shots are always well exposed.
You can try to clean the contacts...
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Forum: Pentax Camera and Field Accessories
12-06-2013, 03:08 AM
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Here is a Metz 58 2 Pentax manual (English)l without other camera information or other languages.
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Forum: Pentax K-1 & K-1 II
08-02-2021, 07:28 AM
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Most ultrawide lenses assume the subject matter is flat and give more magnification the further one measures it from the center in order to keep distortion of a flat surface at a minimum. If you shot a photo of a flat grid, the squares would appear smaller the further they are from the center because of distance if this weren't done. Close to the center, the change in magnification is slight but it increases as the field edge is approached. This makes such a lens fall under the term "rectilinear" (a fish eye lens is not rectilinear).
Now, if you were shooting a flat surface and the surface moved, slewing the sensor could accommodate it pretty well, but shooting the sky is more like shooting the inside of a sphere so when stars move, it isn't like a flat surface moving. Astrotracer can correct for stars near the center field but has difficulties for stars toward the frame edges. Another way to look at it is that the focal length of the lens applies at the center but actually increases toward the edge field and Astrotracer is only correcting for the center focal length. It has little difficulty for longer focal length lenses where the "stretch" is slight but in ultra-wide lenses, the edge field "stretch" is too much, plus there is a rotation component in a star field that a narrower lens doesn't see so much.
The solution is to use a guided mount which rotates the camera and lens with the star field. This will allow near perfect tracking (if set up properly) and will allow the use of ultra-wide lenses without the edge issues (other than a fall off in IQ in such lenses near the edges which can only be improved with stopping down and better lens design). Just one downside of Astrotracer which is unavoidable but there is a workaround if you want to invest in a tracking mount.
ADDENDA: I hadn't looked at your photo but in doing so, AstroDave is correct. Stopping down might help depending on the lens.
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Forum: Welcomes and Introductions
07-31-2021, 07:30 PM
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Hi. I'm an old blue hair, and I started making photographs in 1958. Since I was in my 20's, I've been in love with large-format black-and-white photography, but lately I've found it difficult to take the time to develop negatives and scan them. I have owned Sony A-Mount, Olympus, Fujifilm, Nikon, Lumix L-Mount, and now Pentax digital cameras. I had an extensive Nikon system, but I wanted a camera with an optical finder and shake reduction available for any lens, so I tried the Pentax K-1, and I'm delighted with it. Yes, it's relatively big and heavy, but it fits so nicely in the hand that I don't notice its size or weight. I'm now selling my older equipment and building a Pentax system. I had Pentax film cameras years ago, including a 67 and an MX. I'm looking forward to many interesting discussions on this Forum. Thanks to everyone who makes this possible.
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Forum: Lens Clubs
08-01-2021, 04:37 AM
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Forum: Pentax SLR Lens Discussion
02-02-2018, 07:53 AM
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... the DA15/4 seems to me too the one with the highest resolution in Details
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Forum: Pentax K-1 & K-1 II
09-21-2018, 03:05 AM
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Yoga
K1+FA77 + Cactus RF60x+Magboob
Leura Cascades
K1+Velvet56
The Choke
K1+Velvet56
Fern (colour)
K1+Velvet56
Fern (chrome)
K1+Velvet56
Another Fern
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Forum: Pentax K-1 & K-1 II
09-20-2018, 11:00 PM
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Forum: Pentax K-1 & K-1 II
09-20-2018, 10:30 AM
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K-1 • FF Mode • 100 ISO • Pentax FA 35mm F2 AL
K-1 • FF Mode • 100 ISO • Irix Blackstone 15mm F2.4 • Irix Nano circular polarising filter
K-1 • FF Mode • 100 ISO • Tamron SP AF Di 90mm F2.8 Macro
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Forum: Lens Clubs
02-02-2018, 08:21 PM
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I have been out of action for a while now but i did manage a few trips last year to the western parts of Australia .
Here are a couple of links of some slide show presentations mainly of birds that i captured last year . All of the shots were taken using my Pentax K3II and the Pentax 150-450 lens , including all of the flower shots .
You Tube
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src="https://www.youtube.com/embed/jGkwsvlaVQg?controls=1" allowfullscreen>
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You Tube
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src="https://www.youtube.com/embed/7KJ4omY0AXs?controls=1" allowfullscreen>
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I have found that the Pentax 150-450 and Pentax K3II are a great robust combination and have handled all that i can throw at in in some very harsh conditions without worrying about the gear being knocked around . So overall i am very pleased with the gear , having used it for a few years now . I mainly shoot in TAV mode and manually adjust compensation as needed . For in flight shots i have various user modes set up also using TAV mode with varying shutter speeds and quickly select a user mode that has a shutter speed that suits the light situation and also adjust compensation as needed . I always wait until i have sharp focus before starting any burst rate when following birds . Sometimes when the light is low i wish for a faster lens but i seem to get by in most situations .
Regards Anthony
I did not realize the you tube videos would not be shown automatically at full size here . If you press the You tube logo on the bottom task bar of the video you will be able to view at a decent size . I could hardly see the birds at this small size here .
Regards Anthon[COLOR="Silver"]
---------- Post added 02-03-2018 at 02:46 PM ----------
---------- Post added 02-03-2018 at 02:48 PM ----------
Hi Derek , Is that a Coyote running in the first shot ? I really like this shot , sharp as , well done .
Regards Anthony .
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Forum: Lens Sample Photo Archive
02-06-2018, 07:52 AM
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From Humboldt Redwoods SP:
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Forum: Mini-Challenges, Games, and Photo Stories
02-02-2018, 08:31 AM
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Few of mine:
1. A* 600/5.6 with 1.4 or 2.0 converter, do not remember. Handheld with support from the balcony. The original image is 2800x2800 size from K5. June 2015, Zhukovsky.
2. K 1000/11 Reflex. Handheld with support from the balcony. June 2015, Zhukovsky.
3. Full Moon rising at Mallorca. FA* 24 wide open. Sep 2014.
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Forum: Monthly Photo Contests
01-31-2018, 10:02 AM
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Through glass block window.
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Forum: Pentax SLR Lens Discussion
02-02-2018, 07:00 PM
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17mm TSE. The protruding front element is worrisome.
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Forum: Ask B&H Photo!
01-07-2018, 09:37 AM
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Forum: Welcomes and Introductions
02-01-2018, 06:09 PM
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I learned photography using a Pentax K-1000 shortly after getting married. I purchased two Pentax SF-1 camera bodies - one for my wife and one for me. (The Nikons I looked at didn't have a viewfinder diopter, but Pentax did.) Unfortunately, my wife didn't get the shutter bug, so I had two cameras! Only in the past 2.5 years did I get into digital once Pentax had a 25 megapixel camera (K-3). I should have known that the camera was going to get an upgrade when it went on sale.... and then the K-3 II was out. I have a gym bag full of negatives - a project and a half for when I'm retired. I shoot with Pentax and Sigma lenses.
Love shooting macro, birds (especially the Great Blue Heron and hummingbirds), night photography, sports, and candid photography. Starting to get into portraiture. Because I learned shooting slides and negatives, I am apparently classified as an "old school photographer." I prefer to get everything right in camera. I don't own PhotoShop nor LightRoom (yet.) I also can capture the right moment without resorting to burst mode.
Yes, I have bought stuff recently at Adorama and B&H - I love the videos they post on YouTube, which have been helpful in getting up to speed with histograms and white balance. I also support Canadian camera stores.
I'm looking forward to being a PentaxForums Member!
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Forum: Pentax SLR Lens Discussion
02-01-2018, 04:15 PM
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thank you for the sample images.
looking at the starburst effect on HD15ltd sample and am sure I will never let go of my old green ring 15ltd.
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Forum: Pentax SLR Lens Discussion
01-13-2015, 12:53 AM
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That's a really interesting comparison. I have failed to fall in love with the SMC DA15, and I am on the second copy. If I really want starbursts, my fabulous SMC DA21 does just as well.
I feel a HD DA15 in silver coming on....
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Forum: Pentax SLR Lens Discussion
01-12-2015, 02:52 PM
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I have been looking at the DA 15's and will probably buy one of them. Interesting that the SMC is rated highest (but many more reviews). What gets me are all the comments about soft corners...
First of all, the wide angle of view of a lens like this will also amplify the near-far relationships in your subject matter. This, coupled with shallow depth of field, is in my opinion the primary cause of the perceived corner softness. If you take a photo of a flat object, you will probably have no real problems. One reviewer talked about how the rocks in the lower right of one image were sharp, but the mountains in the top corners were soft...duh????? Get a view camera and tilt the lens forward a bit and that will fix that. My impression is that most of the low reviews are due to a lack of understanding of what a lens like this will do.
Since I do wildflowers/gardens/ ponds/ etc...either version will probably do me fine. I had a Tamron 10-24 for a while and it was not particularly wonderful. It really was too wide at 10 and since I own one of the FA 20-35 (which I love), a prime 15 will probably be perfect.
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Forum: Pentax Forums Giveaways
12-15-2014, 06:48 PM
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And the winning post is on page 164, #2451, which happens to belong to RonHenrdicks1966. Congratulations!
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Forum: Post Your Photos!
12-10-2014, 01:32 PM
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 | Not Work-Safe Curve
Posted By
redcat |
Replies: 2
Views: 398
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Forum: Pentax SLR Lens Discussion
12-10-2014, 11:00 AM
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This is what I wanted to see. Thanks!:lol:
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Forum: Pentax SLR Lens Discussion
12-10-2014, 11:45 AM
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OK - that makes sense. I wondered why such a profound change in the star patterns.
Thank you.
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