Forum: Pentax K-1 & K-1 II
5 Days Ago
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If you can remove the optics of the adapter, it becomes a short extension tube. Of course infinity focus is no longer possible, and short focal length lenses are limited to macro distances. But telephoto lenses may still give you focusing abilities within a useful distance range. It depends on the thickness of the deglassed adapter and the focal length of the lens you're using on it. Another approach would be to find a set of completely manual third party extension tubes for both Pentax K and Canon FD. If they're both by the same manufacturer this is likely ideal. Take the thinnest PK ring and remove the mount intended to accept a PK lens. Replace it with the corresponding mount from one of the FD rings. It's possible, if they are made by the same manufacturer, that the screw holes from the FD mount will match the screwholes of the PK ring with the PK mount removed. This would save immensely on drilling and machining.
This approach should also work by replacing the camera end mount of an FD tube with a PK one; you're just doing the swap at the opposite end of the tube you're modifying. Again, choose whchever ring is thinnest. Mechanical linkages designed to allow aperture control from the camera body are no longer needed and my in fact interfere with the fit of the parts you're trying to put together. Removing them might help.
The thinner the ring the better, because it means you can focus farther out with any given lens than you'd be able to with a thicker ring.
I've not done this myself, so if you decide to try this out, you do so at your own risk.
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Forum: Mini-Challenges, Games, and Photo Stories
08-14-2023, 08:36 AM
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Hi all, it's been a while since I posted. Also a while since I've had something worth posting!
Here's an Osprey that perched right beside the bike path I take to work:
These are cropped from shots taken using my DA 55-300 ED, mostly not at 300mm. I found (as others have found) that results aren't as good at 300 as they are a little backed off.
Enjoy!
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Forum: Troubleshooting and Beginner Help
04-17-2023, 01:36 PM
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You might find the film era Nikon K series extension rings a source for project parts. The combine male and female Nikon F mounts with various lengths of extension tubes with 52mm threads. You can read more about them here: Extension Tubes - Nikon F2 Macro-photography |
Forum: Pentax SLR Lens Discussion
02-12-2023, 09:29 AM
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My own rules for shooting with mirrors are:
a) only shoot in good light and
b) make sure your subject fills the field of view.
Violating either of these rules usually results in disappointment.
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Forum: Pentax SLR Lens Discussion
02-06-2023, 10:43 AM
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I picked up a "Semi Fish Eye" to play with. I'm not where it is right now, and I don't recall the brand. On APSC I'm just losing the corners with a 35mm lens. Here's the original shot:
...and the cropped version:
Ready to Explode
I haven't used it much since my initial test drive, but It's pretty fun. You want to be careful that you don't overuse it, but with careful handling and the right subjects, it can provide striking results for not a lot ogf outlay. As I'm not ready to get an actual dedicated fish-eye lens, this will do for now. |
Forum: Pentax SLR Lens Discussion
01-12-2023, 09:40 AM
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Indeed. Too much extension on too short a lens results in the focus point being inside the lens (which can let you see just how much dust you've got there!) With reversing a lens, you've always got the registration distance as working distance.
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Forum: Pentax KP
01-11-2023, 12:30 PM
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Yes, that gannet shot is terrific! Surf's Wind's up!
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Forum: Mini-Challenges, Games, and Photo Stories
01-11-2023, 12:25 PM
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Or, you've uncovered hyperdimensionality in cats; which I think would explain how they'll intently watch something that doesn't appear visible to us.
Of course your cat will now have to kill you. And anyone who's viewed this post. Secrets must be kept.
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Forum: Pentax DSLR Discussion
01-01-2023, 09:11 PM
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Forum: Pentax KP
12-11-2022, 08:06 PM
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Be aware that when shooting with electronic shutter, while the shutter speed may nominally be 1/1000 of a second, the entire frame is not exposed at the same time. It's much like the travelling curtain of a film camera in which a narrow slit passes over the frame, so that each part of the frame gets 1/1000 sec. exposure, but only as the slit travels across that part of the film. The two shots below were taken with a mirror lens at 1/2000 sec. using ES, LV and wired remote. The branch the hawk was sitting on was moving up and down in the wind, stretching the bird in the first shot compared to the second:
If I recall correctly the "read speed"of ES is in the range of tenths of a second, essentially lengthening a shutter speed in the thousands of a second by a factor of approximately 100. That is to say that the very bottom of the frame will be exposed about 1/10 sec. after the top. I believe this is what causes what's known as "rolling shutter" in video. In subjects moving rapidly in the horizontal plane, this can give them a slanted or skewed look. The rotating blades of a fan or aircraft propellor can end up looking very strange indeed.
Here's a Forum discussion of MS vs ES: Electronic Shutter (vs Mechanical shutter) questions - PentaxForums.com |
Forum: Pentax SLR Lens Discussion
12-10-2022, 10:14 AM
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I've been very pleased with my results from the Tamron 55BB 500mm mirror. I try to avoid using it if a) there isn't a lot of light and b) I can't fill my frame with the subject. Violating either of these rules tends to get photos deleted. Maybe yours is a bum copy or, you weren't using the right mallet. Here are some of my images from this lens: Mirror, mirror: Tamron 500mm | Flickr
Another vote for the DA 55-300. Mine is the non HD, non WR version. Here are shots from it: Adventures with the DA55-300 Feb.24, 2020 | Flickr
Both are easiliy hand holdable and offer good close focusing capability.
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Forum: General Talk
11-17-2022, 07:21 PM
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Steve's posts were always knowlegdable and encouraging. He enriched this forum, and its members, immeasurably. He will be missed.
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Forum: Lens Clubs
11-16-2022, 02:42 PM
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Yes, that's the case. It does eat up a bit of working distance, but it's an easier solution than jamming something against the lens's aperture control tab. An adapter with aperture control for mirrorless is going to use up more working distance, so going for an adapter intended for DSLR is going to be more convenient.
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Forum: Lens Clubs
11-03-2022, 11:01 AM
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I think I see something with a leg on the top left edge of rightmost mushroom?
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Forum: Lens Clubs
10-23-2022, 07:22 AM
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Thanks! Couldn't tell you what number. The ring on the adapter that lets me control the diaphragm indicates open and closed at either end of its throw. There are no click stops on the ring (or, obviously, the lens). I usually try to have it somewhere in the middle. I don't know what that numerical value would be, and have never bothered to try working it out. Could be f8-ish. As the 18-55 is lighter, more compact, and user friendly, I'm more likely to use it in this way than the 16-85.
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Forum: Mini-Challenges, Games, and Photo Stories
10-19-2022, 12:53 PM
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Cool!. I've done some messing around combining high contrast B&W with oversaturated colour to give a comic book style look. I've probably posted these before, but what the hell. |
Forum: Mini-Challenges, Games, and Photo Stories
10-19-2022, 12:40 PM
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Let's see.
Planes?
Check.
Trains?
Check.
Boats?
Check.
Automobiles?
Check!
Okay, what do I win?
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Forum: Mini-Challenges, Games, and Photo Stories
10-19-2022, 12:03 PM
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Fall colours in motion. |
Forum: Mini-Challenges, Games, and Photo Stories
10-19-2022, 12:00 PM
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Lots and lots of trees...
Agawa Canyon
Ten Mile Point, Manitoulin Island |
Forum: Mini-Challenges, Games, and Photo Stories
10-18-2022, 07:21 AM
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That would be the Thousand Islands, at the eastern end of Lake Ontario. I've taken a cruise there, too! The 30,000 Islands is in Lake Huron, entirely in Canadian waters. Both are very scenic and picturesque. The 30,000 Islands are more wild and rugged, consisting of ancient rock with hardy, wind-sculpted trees clinging to them.
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Forum: Mini-Challenges, Games, and Photo Stories
10-15-2022, 09:09 AM
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Some stitched panoramas from a recent trip to Northern Ontario:
Parry Sound:
Sudbury:
Agawa Canyon:
Manitoulin Island: |
Forum: Mini-Challenges, Games, and Photo Stories
10-15-2022, 09:00 AM
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Rock, trees, and sky, 30,000 Islands, Georgian Bay, Ontario. |
Forum: Mini-Challenges, Games, and Photo Stories
10-15-2022, 08:57 AM
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Views taken on a cruise through a small part of the 30,000 Islands. Situated along the eastern shore of Georgian Bay, Lake Huron, it is the largest freshwater archipelago in the world. |