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04-28-2014, 05:14 PM   #16
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Okay! I tried the tin foil out with the lens fully engaged on the body; I wanted to see if things would just work. And they did! Took a picture at f16 (max aperture) and it came out with basically no light to the image. Then I took this of that same house, at f8;

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0669_zpscc6ce85b.jpg

To see if there were any changes for the close / wide open stuff, I took another picture of the kit lens sitting on my desk;

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0673_zpsed84efd8.jpg

I did use the Green Button and I have it set for full manual with an aperture ring in the Custom Menu. I'm a little embarrassed about how much I've learned about my camera already through this.

Thank-you again for your help, everyone.

04-29-2014, 06:32 AM   #17
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I was on the same learning curve a year+ ago, happy to help.
Lens doesn't look like its up to much tbh - ebay!
04-29-2014, 07:02 AM   #18
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QuoteOriginally posted by marcusBMG Quote
I was on the same learning curve a year+ ago, happy to help.
Lens doesn't look like its up to much tbh - ebay!
I was pretty excited about learning how to drive a full manual lens, including f-stop. I figured there were fewer crutches available to get a decent picture out of the thing.

So I may still keep it. Or maybe just get a 28mm f2.8 SMC M from KEH for about $90? I guess that would take some of the dice roll out of getting a good copy, as I trust KEH, But I think before I do that I'll pull out my custom color curving and see what it does in different conditions. I'll leave the tinfoil strapping in place, it's easier to deal with than I thought it would be, and come back to this thread later in the week with results. I kind of like the bokeh on the close indoor shot of the other lens.
05-03-2014, 06:37 AM   #19
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Theres no such thing as a bad lens.


This lens is fine, you now have a soft focus lens and you've saved yourself 100 dollars by not having to go out and buy one.


Choose the amount of softness you desire by selecting the aperture, it should be pleasantly sharp by f8


Take some portraits of your wife and she will think your a photography god.


Keep it in the cupboard until you need it for portraits of ladies who don't like their picture taken. They will beat a path to your door.


If you don't like it send it to me.


On second thoughts its a rubbish lens and you should dispose of it properly by sending it to me, and any other "rubbish" lenses you find.


Thank you very much.

05-03-2014, 10:06 AM   #20
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QuoteOriginally posted by pres589 Quote
I think it's an offshoot of the Vivitar primes from the 70's and 80's but I can't find anywhere on the Internet that talks of a Kalt in Pentax K.
Yes, this lens dates to the late 70s or 1980s, but no, it is not related to any of the Vivitar lenses. Kalt was (and still is) a re-brander of inexpensive photo accessories. At one point, they also dabbled in cheap lenses. Your 28/2.8 is one of a score of generic lenses that were common at the time and would have been equivalent to a Focal or Hanimex. Yours probably was not bad when new, but your photos indicate a lens in distress.


Steve

---------- Post added 05-03-14 at 10:09 AM ----------

QuoteOriginally posted by pres589 Quote
Or maybe just get a 28mm f2.8 SMC M from KEH for about $90?
...or get a Vivitar* or XR Rikenon of the same vintage for about $30 USD. For some reason, the prices on Pentax-M 28/2.8 lenses has skyrocketed. I can't imagine why since the lens was actually priced (about $35 IIRC) below that of a Vivitar (about $45) when new and is not a standout in any way other than the SMC coating.


Steve

* I have a Komine-made Vivitar 28/2.8 and it is a very fine lens.

Last edited by stevebrot; 05-03-2014 at 10:19 AM.
05-03-2014, 12:35 PM   #21
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QuoteOriginally posted by stevebrot Quote
Yes, this lens dates to the late 70s or 1980s, but no, it is not related to any of the Vivitar lenses. Kalt was (and still is) a re-brander of inexpensive photo accessories. At one point, they also dabbled in cheap lenses. Your 28/2.8 is one of a score of generic lenses that were common at the time and would have been equivalent to a Focal or Hanimex. Yours probably was not bad when new, but your photos indicate a lens in distress.


Steve

---------- Post added 05-03-14 at 10:09 AM ----------



...or get a Vivitar* or XR Rikenon of the same vintage for about $30 USD. For some reason, the prices on Pentax-M 28/2.8 lenses has skyrocketed. I can't imagine why since the lens was actually priced (about $35 IIRC) below that of a Vivitar (about $45) when new and is not a standout in any way other than the SMC coating.


Steve

* I have a Komine-made Vivitar 28/2.8 and it is a very fine lens.
Yeah, I'm starting to wonder if anything I learn from this lens is going to be "wrong". I have to stop the thing down so far to get a clear picture out of it that even with the ISO at 800 and in a decently lit room, I have to run a long exposure time to get enough light in to do anything.

I just ran some back to back shots here at my desk of a speaker. First up was the Kalt and it's sort of... you've seen what it does. Back to back against the 18-55mm kit lens that came with my old K100D, I think I like the kit results better. I don't think this is a fungus issue, I think this lens is damaged from sitting at the bottom of a box of lenses, which is where I found it in the local used camera gear shop. And this wasn't a neatly organized box; it was a jumble.

What's unfortunate is that my work is sending me to Spain a couple weeks for a week or so and I'd love to have a good camera with me for shooting in my free time there. Instead I've got this. And renting for the time I'd need it ends up costing so much that it doesn't make much sense. I think I'll just take the 18-55.

I'll probably keep the Kalt just for messing with but I agree with your suggestion. I'll be in some major cities in June and may stop at some shops and see what I can luck into as far as a nice manual prime (I'd love an FA* 24 but I can't rationalize it at my level of experience).
05-03-2014, 04:45 PM   #22
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If I might be so bold, try this quick and dirty test.


Find a long picket fence and stand at on end of it, focus midway along it and use the widest aperture, then take a shot.


Then reset the aperture to f8 and retake the same shot.


This will reveal where the lens is focussing, how sharp its focussing and the depth of field at 2 settings.


Crop the 2 images to expand the area of sharpest focus on each, and then post all 4 images.


Then we will be able to see how the lens performs. - If the lens is a poor design, if theres an internal misalignment, if theres a focussing issue.
05-03-2014, 05:07 PM   #23
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QuoteOriginally posted by Imageman Quote
If I might be so bold, try this quick and dirty test.


Find a long picket fence and stand at on end of it, focus midway along it and use the widest aperture, then take a shot.


Then reset the aperture to f8 and retake the same shot.


This will reveal where the lens is focussing, how sharp its focussing and the depth of field at 2 settings.


Crop the 2 images to expand the area of sharpest focus on each, and then post all 4 images.


Then we will be able to see how the lens performs. - If the lens is a poor design, if theres an internal misalignment, if theres a focussing issue.
What, with the focus ring set to infinity?

05-03-2014, 08:12 PM   #24
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As I said focus halfway along the fence,


Forgive me if im presumptious here but your question suggests you may not be very experienced focussing a manual focus lens on a digital camera.


Its extremely difficult on some lens and camera combinations. I myself have a lens that's very difficult to focus well manually.


Im wondering if this could be part of the issue, it will be revealed by the test I suggested, I will ask you to add something to make it more revealing.


Place a physical marker beside the fence at the point you will focus, lets say 20 feet away, something like a sports bag or a tripod, and use that as the subject to focus on. If its beside the picket fence, you should easily see if the object and the fence beside it are in focus. If they are both in focus your focussing is good, if they are not and the sharpest focussed fence is somewhere else then your missing focus.


It usually takes me many test shots to start nailing focus manually with a new lens.


One other thing, I don't know how your camera is set up, you said you set it to auto everything. What settings are you using. Could it be conceivable that some setting on the camera is doing something that interferes with a steady shot. I once heard of a setting on the camera that expected an auto lens and the lack of it caused some kind of hunting action and the image quality was degraded.


Has anyone else found this.


Can you review all of the settings and note them down just in case theres something wrongly set.
05-04-2014, 05:51 AM   #25
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+1 to imagemans remarks on focussing MF (exacerbated for me by my myopia, I have to use a negative diopter correction lens in addition to the in camera viewfinder adjustments), and I add that the viewfinder screen in your K5 isn't really designed for manual focussing. Many (most) of us change the VF screen to a better one.
However for the immediate tests - no problem. Use live view! On my Kr I press info to magnify the screen image up to 10x.
05-04-2014, 12:19 PM   #26
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Okay, so I found a picket-esque fence not that far from my house, and shot down the face of it. There was a post that I paced off to about 20 feet to use as a focal point. Camera set to M, ISO 100, Green Button used to find settings for me, and I used Live View with some magnification to try and find best focus. At one point I actually got a red dot from the focus catch but for the most part the pictures seem just out of focus. Best focus found with the focus ring set to infinite. I know this isn't right; the post is about 20 feet away, so something under the 30 demarkation would seem in order. But crank in on the focus ring and it all went fuzzy. Here we go;

F2.8, full size.

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0736_zps92891128.jpg

Cropped to what seems most sharp. Note: This crop of the -736 full size seems sharpest at the post closer to me, not the one I am actually focused on.

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0736_crop_zpscf6146e5.jpg

F8, full size.

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0738_zps4d9021d3.jpg

Cropped. Sharpness has moved to about where it should be, probably about a foot or so closer to me than it should be, but it's better.

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0738_crop_zpse33c0ea9.jpg


Something I noticed when I was getting ready to mount the Kalt back on my camera; there's very quiet clicking or ticking sounds if I roll the lens over front to back. Just slowly rolling it from face to mount up, and back again, will produce these sounds. This seems Not Good.

Imageman: You're correct about manual aiming of a lens like this, really in general. I appreciate your help on this one. I wanted to make sure I was following your "test plan", so to speak, in the way that most matched what you hoped to review from this lens.

marcusBMG: Thanks for the advice on how to best use LV. With it at standard magnification, I didn't find the function to be worth much here, but 4x and 6x are extremely useful.
05-04-2014, 12:35 PM   #27
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Another thing to keep in mind when trying to manually focus - you have to make sure your camera diopter setting is set for your eyesight. Otherwise, most every manually focused photo you take will be out of focus.
05-04-2014, 12:51 PM   #28
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QuoteOriginally posted by pres589 Quote
Something I noticed when I was getting ready to mount the Kalt back on my camera; there's very quiet clicking or ticking sounds if I roll the lens over front to back. Just slowly rolling it from face to mount up, and back again, will produce these sounds. This seems Not Good.
I don't know anything about the design of that particular lens. If it is a loose element then your image quality is going to suffer greatly. It could also just be normal movement of some of the mechanical parts inside the lens.

I looked at other pictures of a Kalt 28/2.8 and it is not like any 28 I've seen before, I have no idea who the original manufacturer could be.
05-04-2014, 06:16 PM   #29
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Ok thanks for doing the test, I believe it has identified the issue.


What I am seeing is chromatic aberration.


This is typical of a misaligned element and I believe its unmistakeable.


Look at the f2.8 large, do you see the glow surrounding the fence palings, on the crop its even more evident.


On the f8 shots it has largely disappeared. This behaviour is absolutely typical of a badly misaligned or badly assembled lens.


The cause is usually a loose or wrongly assembled element, possibly an internal element due to someone messing with the lens before you got it.


Disassembling and reassembling the entre lens could fix this, but your as likely to make no difference to it or make it worse.


The rattle you hear on turning it over confirms that there is maybe a loose element internally.


Personally as its a cheap lens, I would risk it and unscrew it. Does it appear to have been taken apart by an earlier owner?


Maybe if it was, an internal element was put in the wrong way round or the elements just weren't packed in tightly.


The last lens I took apart to fix an issue like this unscrewed entirely from the front, the ring with the name on it unscrewed easily (use a pair of scissors with tips inserted into the 2 tiny holes in the ring. Every element and spacer then came out freely.


If you do take it apart, handle each element carefully placing them in order on a long tissue, carefully clean each part, lenses and spacers, then replace them in situ, and hit them as hard as you can with your finger to seat them (using a tissue), thats the only way to seat them firmly. And maybe the guy who assembled the lens last should have done this.


Be prepared to have to repeat the disassembly reassembly a few times. If after 3 goes its no better, try reversing an element, an internal concave element is a good candidate.


That last lens I worked on by the way was transformed and is now one of my best lenses, so its worth having a go.


Good luck with this and above all dont panic.
05-04-2014, 07:36 PM   #30
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There's a small marking in each of the two small lots on the front casing. I believe this lens has been dismantled at least once based on that marking. Overall the lens is physically in pretty good order; I wonder if someone took it apart to clean it, messed it up, and gave up on it.

keh.com has "misc branded" 28mm f2.8's for $43 listed online. I'll call on this after I get back from some stuff going on out of town and see what they have to offer, as well as keeping my eye on the classified ads here on the forum. I am not optimistic on my being able to repair the lens myself.
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