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Forum: Pentax SLR Lens Discussion
07-29-2014, 09:21 AM
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Negative on the 58mm. Doesn't fit.
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Forum: Pentax SLR Lens Discussion
11-02-2012, 06:52 PM
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It looks like the focus ring isn't attached in the right place. The front barrel on your lens is sticking out about the right amount for infinity - or at least, a lot farther away than infinity. If you still can, send it back and get a refund.
Back in my day :), the sellers would just laugh at the idea of a refund, so I learned to fix these myself. Turn the focus ring as far as you can towards infinity, without forcing it at all. You need something to unscrew the front trim ring that says SMC Pentax-M 1:1.7 50mm etc. Something rubber will work, like a chair leg protector, large rubber stopper, etc. Just make sure it doesn't touch the front element. The ring unscrews through the filter threads. Then your lens will look like this:
Use a #00 screwdriver to remove the screws marked with red arrows, leaving the ones in cutouts alone. Now you can take off the filter ring/front barrel and see this:
There should be three screws on your lens like the ones marked with red arrows. Loosen all three and the focus ring should turn without focusing the lens at all. It has two mechanical stops to keep it from rotating completely around but it should turn freely. Turn the focus ring until it points at the infinity mark. Then tighten one screw.
Now you need to set infinity more precisely. I think your lens is probably focusing slightly beyond infinity right now. Mount it on a camera and try to focus on something several miles away, the furthest thing you can see. If I'm right, you'll have to turn the focus ring back to maybe the 25 foot mark. When you're happy with the focus, loosen the one tight screw, turn the focus ring so the center of the infinity symbol lines up with the orange diamond, then tighten all three screws.
Optional maintenance: Some of these lenses are dirty inside so I usually have an old toothbrush handy to brush out debris. Then I'd check to see if the aperture is fully open at f1.7. You shouldn't see any of the aperture blades. If you want to adjust this, set the aperture ring to f1.7 and loosen the three screws that were in cutouts in the first photo. Then you can rotate the whole optical assembly. If you turn it one way, the blades disappear. Rotating the other way makes the blades stop down further. Rotate the assembly until the blades just disappear, then tighten the screws. Check to see if they continue to stop down at each position on the aperture ring. Then tighten all the screws.
Now you can reinstall the filter ring and trim ring and start using the lens.
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Forum: Pentax SLR Lens Discussion
07-23-2014, 08:53 PM
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Don't be afraid of going the epoxy route with WHATEVER material comes to hand. If the interior is flat black and it's strong enough to support the lens weight a DIY solution will deliver the same results as a $$$$ classic bellows or extension tube set.
Nesting diameter PVC tubing and epoxied lens/body mounts with a l'il flat black spray paint can duplicate a lot of very expensive hardware. Then only thing that counts in the results is dark millimeters of extension no matter how you get them or how expensive the gear.
Remove the glass from unused B&W filters and canibalize old lenses and forlorn bodies for end connectors.
Experiment with hand-held cardboard toilet paper tubes and duct tape as spacers 'til you get it right! Field expedient solutions rules -- McGyver-it.
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Forum: Pentax SLR Lens Discussion
07-16-2014, 09:03 PM
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The m42 lens Hanimar 135 f3.5 this is the same as the Photax 135mm f3.5, (rebadged) 10 dollars should secure a copy
This has 3 elements that all are forward of the aperture and are removed by unscrewing a single o ring from the front. Spacers all come out leaving the outer tube focus helicoil and aperture intact. Insert your elements with your own spacers and replace the o ring,
The m42 lens Helios 44 58mm f2 20 dollars should secure a copy
This has 6 elements 3 in front of the aperture and 3 behind. The rear 3 elements are held in a block which unscrews entirely leaving the aperture exposed, discard this.
The front 3 elements should be removable from the front by removal of o ring to allow reinsertion of your own elements and spacers. You will have to add extension tubes or a bellows to give correct focus.
The m42 lens Yashica Yashinon 50mm f1.7 20 dollars should secure a copy
The lens construction is exactly the same as the Helios, the 3 rear elements unscrew ina block leving the aperture exposed and all remaining elements in front removable from the front. Treat it exactly the same as the Helios.
I have not removed the front elements from the Helios or the Yashinon but they should free up and remove easily, I have removed the rear elements from both however and its a simple job.
I have removed all elements from the Hanimar/Photax and that's easier than the Helios or the Yashinon.
I would recommend re using old m42 lens bodies because they are very cheap and available, and come complete with aperture diaphragm and focus mechanism.
It is quite acceptable to have all elements in front of the aperture blades.
Hope this helps
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Forum: Film Processing, Scanning, and Darkroom
04-27-2014, 02:16 PM
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The trim ring with the serial number probably unscrews and there are either retaining rings or screws underneath. Something like a rubber end for a chair leg will probably serve as a good tool to unscrew the trim ring. Retaining rings would use a spanner but you can improvise with a set of calipers, scissors or the like. I don't recommend using a screwdriver - you can do it but one blade tends to slip.
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Forum: Pentax K-5 & K-5 II
02-25-2013, 04:49 AM
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I never knew about that, though it explains a shift I noticed when opening some files in Lightroom.
Thanks, maxfield_photo.
LowVoltage, on my K-5 IIs, it's Custom Menu 2, #10.
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Forum: Pentax K-5 & K-5 II
02-25-2013, 02:23 AM
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There is an option in the custom function menu to allow the camera to make minute adjustments in the white balance even when it is specified by the user. Stupid if you ask me, but maybe it helps with florescent lighting which cycles in color. By default it is on. Look through the menu, you'll find it, I can't remember the number off hand.
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