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Forum: Lens Clubs
05-09-2018, 04:17 PM
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I will lock lens down in padded machining vise on my drill press and use a drill bit of proper size, ( mic. pin ), with a stop collar on it, as hole is very shallow. Measure/ level 4 times, drill once..... Being Aluminum, these will cut very easy. The camera lens mount locked to the M42 adaptor will guide the bit, but accurately centering/leveling and correcting any bit run-out is imperative. Don't want bit cutting into camera mount hole at all, enlarging it. As, my other lenses have larger diameter against camera mount then the 300, this will be an actual hole not a groove. Probably buy M42 cheap extensions on ebay to drill first, to make sure of correct register.
Camrea Macro Extension Tube Ring for M42 42mm Screw Mount 3 Ring Adapter L8D | eBay
P.S. Just bought my very first modern auto lens for my K70, a Sigma, 17-50mm F 2.8. And, noticed the "hole" in lens mount for pin lock is not round but a oblong, "racetrack", shape. I quess now I understand comments about using a "router". I suppose this is something to do with some kind of slightly different register with some camera mounts? Have to study this a little more before machining my Taks.
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Forum: Lens Clubs
05-09-2018, 12:17 PM
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Scored a lens mount on ebay to use for a drill guide for locking pin into M42 lenses, $13 with shipping.
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Forum: Pentax SLR Lens Discussion
05-07-2018, 11:28 AM
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Thanks,
My error, missed one dot, thought is was being advertised as a f1.2..( red face )....
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Forum: Pentax SLR Lens Discussion
05-07-2018, 10:41 AM
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This just does not look right, no serial # or "made in Japan"? Nor does the size of the lens look correct for a 1:2?
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Forum: Lens Clubs
05-07-2018, 08:27 AM
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Bought this new in 1968, has; six blades, 77mm filter size and a Manual/Auto slider
One very good reason for leaving an adaptor on this lens is the tripod adaptor clamp. The fiddle time to try and
screw it to the adaptor on camera, with the DSLR's penta prism overhang, and grip, is just unacceptable. Was not a problem on
my Spotmatic.
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Forum: Lens Clubs
05-06-2018, 09:03 PM
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The other funny thing about my 300mm , is that the locking pin almost misses the barrel. It has the smallest diameter there then any of my other lenses. Only about 1/8 of the pin is touching the barrel. After juggling with it today, shooting some Elk about 1/2 mile away, I decided I had to make that pin work. Otherwise, because I keep the adaptors on the lenses, and have removed the spring locks, the greater friction of the focus ring on this big lens tends to twist it off of the camera. So, I was trying to focus, hold the lens on and work camera, needed 3 hands. Tonight I decided to file a notch in the lens for the pin. Having some small swiss files at hand. However, having had this lens since in my 20's and having kept it pristine, it was "sweat time". Used a sewing needle to scribe the pin's center on the barrel and started my very slow filing of the Aluminum. Cut, fit, cut fit..:
taking with my Nexus 5X phone
A black touch up paint stick, and now I hear that reassuringly click as lens locks up.
I plan on drilling my other lenses when I can get another K camera body mount from another camera's parts, to use
as a template. Using my drill press and being very careful.
Rascals busting fences:
K-70 300mm Super Takumar 1/500 f? ISO 400 cropped subjects 800 yds. away
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Forum: Lens Clubs
05-06-2018, 07:55 PM
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Yes, that system would change distance.
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Forum: Lens Clubs
05-06-2018, 09:59 AM
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Problem with focus with the 24mm, was a combination of condition and my errors. I found a very slight haze or film on the Skylight A1 filter that had been on it for 40 yrs. So took it off, then I noticed I had tried to focus without my distance glasses, which the diopter was set for, and lastly, I had left the focal length at 135mm. After those corrections, infinity photos are as sharp as with other lenses.
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Forum: Lens Clubs
05-05-2018, 07:55 PM
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Yes, my 300mm is like that, but other lenses are different, solid back there, no screws. But, don't see how this would change camera body to rear lens distance. Unless shims are somehow allowing inside barrel to come back further?
My 300mm seems fine:
First shot from my K-70 Super Tak.; 300mm at 1000 yds. f4- 1/1000 sec
ISO 400, Cloudy hand held.
Cropped, post sharpened and contrast and exposure improved:
---------- Post added 05-05-18 at 08:47 PM ----------
Lovely, I can smell the salt...... Haven't put my 17mm Tak. on my K-70 yet. Let's see, 1.5 conversion = 25.5 mm.
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Forum: Lens Clubs
05-05-2018, 04:21 PM
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typo, meant, "or actually on the lens itself?.
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Forum: Lens Clubs
05-05-2018, 02:55 PM
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Do you mean the shims are in the adapter on actually on the Lens itself?
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Forum: Lens Clubs
05-05-2018, 11:17 AM
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So far, this one lens is only one that will not focus at infinity? Using OEM Pentax M42 adaptor.
Looking these directions for adjusting AF, it says to set Focus to Auto and do adjustments?
How does this work when these lenses have to be used in Manual? Have battery out charging right now, so thought I'd ask first.
Was one of my favorite lenses, when on my Spotmatic, very sharp..
Fixing Front and Back Focus - The Remedy - In-Depth Articles |
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Forum: Lens Clubs
05-04-2018, 08:32 AM
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Glad I kept the 6 prime Super Taks, I bought while stationed in Vietnam. Kept putting off buying a digital body, waiting for full frame Pentax prices to drop. Well, couldn't wait any longer, one only lives so long...
Just got new K-70, and 3 Pentax brand M42 adaptors. Using Av, after making other settings. So, don't need green button. Must disable auto ISO also. When camera turned on, must verify focal length.
Didn't have time to read through all these threads, so if I'm repeating anyone else here, excuse me:
Now, I just focus at wide open, turn aperture ring until I see shutter speed I want in viewfinder, and snap away. If viewfinder is too dark, I increase ISO, (400 is what I seem to use most), shooting wild critters @ 1/500, depending on depth of field I want.
Decided to put adapters on lenses instead of camera for faster lens swap. After looking at new lenses prices, the $80 for an adapter is still a bargain. I had read the real Pentax adapters were not available, any longer however, B&H shows they have them.
You have to remove the tiny Phillips screw and spring from it to use on lens. I had problem with this with tiny jeweler's screwdriver, could not get enough torque to start screw moving. So, clamped small needle nose vice grip pliers to driver shank, made sure tip was hard set into screw and turned it out. You have to have correct size Phillips bit, it is tiny. If driver is not exactly right size, you will strip the head and then a have a real problem. If it still does not want to move, I suggest soaking it in Kroil, ( which I also did on one ), overnight, but make darn sure you get all Kroil off with a, no residue solvent, afterwards. That oil will migrate into camera or lens if not totally removed. I used a toothpick soaked in Kroil, then placed tip of it against back of screw, letting oil migrate into threads.
Other little problem is, after lens is attached and removed, the adapter is really hard to get off lens. I could not do it with my fingers as the edges on it are kind of sharp. Tried with leather gloves and just got it off, but then tried a sheet of rubber 1/8" thick cut to about a 3" square, pressed against adapter and twist, comes off fairly easy. I have 3 adapters and 6 lenses, so will have to swap adapter now and then. And, this way, if I get some auto lenses, don't have to go through the real pain of removing adapter from the body, trying to compress that little spring with a tool and turning adapter at same time.
Super Taks I have; f4-17mm fisheye, f3.5-24mm, f1.4-50mm, f4-50mm Macro, f2.5-135mm, f4-300mm. All bought new in 1968.
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Forum: Pentax K-70 & KF
05-04-2018, 07:16 AM
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Forum: Pentax K-70 & KF
05-03-2018, 01:47 PM
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Old School, now playing with flash on new K-70:
Manual shows 12m (meters), Guide no. @ iso100, or about, 40 (ft), for onboard flash GN.
After some testing, I find using iso 400, the GN is a little less then 60, but is an easy number to use in my head. And, Iso 400 works well with my f2.5 135mm. Which I liked and used a lot for stand off portraits when on my film camera. I set flash power to, full.
So, at 20 ft., in Av, which locks shutter to 1/180, (flash sync), when flash is popped up, Guide No. divided by distance, 60/20 = f3 or f3.5
At 5 feet, 60/5 = 12 or f11. Very light or dark objects, of course require adjustment. Small f-stops are too dark for focus in dim light, so that's done wide open @ f2.5 then stop down for shot. Has it's limitations, when trying to pick instant for moving subject in dark viewfinder, so consider using, iso100, for close photos, or reduce flash power with larger f-stop, depending on depth of field effect you want. And/or keep enough ambient light on subject for focusing.
Using iso 100, and GN of 40, 40/10 ft. = f4. With this lens, I find about 15 feet distance needed for head shots, @ full power, so again using iso 400, 60/ 15 = f4. And,15 ft. works well with bashful subjects. But, I still have to grin with instant proofs, instead of the wait with film development. :D
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Forum: Pentax K-70 & KF
05-03-2018, 09:49 AM
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New to forum, so if I missed this already being revealed please excuse me. Back in the late 60's when in Vietnam I purchased a Spotmatic and many prime lenses, from the standard Super Tak. 50mm to a 300 mm. Very,very, cheap then, even at a Corporals wages. I used these for many years with film. These lenses sat in a case for many years, after going digital with some point and shoots. I was waiting for prices of a full frame Pentax DSLR to become reasonable. I did purchase a original Pentax M42 adaptor.
Well, couldn't wait any longer, just bought a K70. I'am now amazed how sharp and fast these Super Takumars really are.. After re-setting up settings to manual, finding the Tv-shift under the e-dial programing was the most difficult. I use the Av mode and the ISO locked at 400. That way, when I rotate the aperture ring I can watch the shutter speed change in the viewfinder. And, do not have to use the green button. So merely, focus, press shutter to see speed then rotate to 1/500, for action, and take pix. In normal daylight, this is around f5.6, a good sweet spot for the f2.5 135 mm. I use the most. With the 1.5 conversion, this equals a 200 mm telephoto. On my wildlife shoots, I can normally just leave lens at f5.6, stay focused on moving beast, and snap away.
Something I have not come across yet, is the anti-shake setting for a M42 should it be the full frame mm or the 1.5 compensation? I have been setting it at 200mm, for the 135mm, and doesn't seem a problem.
Super Takumars; f4 17mm, f3.5 24mm, f1.4 50mm, f4 50mm macro, f2.5 135mm, f4 300mm.
Read more at: How to use/meter Manual & M42 Lenses on all Pentax DSLRs (K-1, K-3, K-5, K-30, etc) - Page 22 - PentaxForums.com |
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Forum: Pentax Lens Articles
05-03-2018, 09:17 AM
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New to forum, so if I missed this already being revealed please excuse me. Back in the late 60's when in Vietnam I purchased a Spotmatic and many prime lenses, from the standard Super Tak. 50mm to a 300 mm. Very,very, cheap then, even at a Corporals wages. I used these for many years with film. These lenses sat in a case for many years, after going digital with some point and shoots. I was waiting for prices of a full frame Pentax DSLR to become reasonable. I did purchase a original Pentax M42 adaptor. Well, couldn't wait any longer just bought a K70. I really am now amazed how sharp and fast these Super Takumars really are.. After setting up camera to above settings, finding the Tv-shift under the e-dial programing was the most difficult. I use the Av mode and the ISO locked at 400. That way when I rotate the aperture ring I can watch the shutter speed change in the viewfinder. And, do not have to use the green button. So merely, focus, press shutter to see speed then rotate to 1/500 and take pix. In normal daylight this is around f5.6, a good sweet spot for the f2.5 135 mm. I use most, with the 1.5 conversion, this equals a 200 mm telephoto.
Some thing I have not come across yet, is the anti-shake setting for a M42 should it be the full frame mm or the 1.5 compensation? I have been setting it at 200mm, and doesn't seem a problem.
Super Takumars; f4 17mm, f3.5 24mm, f1.4 50mm, f4 50mm macro, f2.5 135mm, f4 300mm.
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