Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-27-2014, 03:56 PM   #1
Site Supporter
Site Supporter




Join Date: Jan 2014
Location: West Haven, CT USA
Photos: Albums
Posts: 1,070
Is it me, this Kalt lens I picked up, or what?

A couple days ago I stopped in the local camera shop and found this very interesting (to me anyway) lens;



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. This is not an M-type screw mount. So I mount it on my K-5 II and start playing around. This is a full manual lens with an aperature ring and I felt this would be a great lens to really learn on.

And then I get pictures like this out of it;



Fullsize with in-camera jpeg compression here; http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/kalt_house_...psfacb2ccd.jpg

This was shot with an f-stop of 11 and the camera set to auto. I played around a little and they're all some version of this; blurry and out of focus. I shot this off of my covered porch so I was in the shade. To see if my camera is suddenly not in good shape, I took the following with a Pentax 18-55 kit lens from 2006;



Fullsize here; http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/kit_house_full_zps09395740.jpg

I want to think there's something I'm not doing correctly with this thing but maybe this just isn't a good lens, or isn't a good lens for an APS-C DSLR? I can get fairly decent focus up close but it's a bit of a roll of the dice as far as getting there... focusing this thing is a real challenge. And using the live preview usually gets me results that are not as good as using the viewfinder.

Any suggestions? I've been lurking around this forum for a bit and really appreciate it as a resource so I hope I'm asking this right. Oh, and the colors are a little off because of how saturated images are when using the Kalt, so I tweaked the saturation and hue a little for that lens, and just ran with those settings with the 18-55 mounted. The "Bright" color etc setting from the factory was really blown out, especially reds.

04-27-2014, 04:30 PM   #2
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 1,553
Do you get sharp pics close up?

QuoteOriginally posted by pres589 Quote
This is not an M-type screw mount
Your terminology is off here. Normally a screw mount lens is the ubiquitous M42 thread, used by a number of camera/lens manufacturers inc Asahi Pentax. Is that the mount? And if it is what adapter are you using on the camera? You will lose focus with a rimmed adapter exactly like the pic. see here
04-27-2014, 04:38 PM   #3
Pentaxian
Kozlok's Avatar

Join Date: Jun 2012
Location: Albuquerque
Photos: Gallery
Posts: 1,793
Does it work better focused close up? Could be that the focusing helicoid is out of alignment. Looks like it'd have to be out by a mile, though!

Maybe the lens is just junk. I have an old Formula 5 28mm that I got for $10 or so, and it's miles better than this!
04-27-2014, 04:53 PM   #4
Site Supporter
Site Supporter




Join Date: Jan 2014
Location: West Haven, CT USA
Photos: Albums
Posts: 1,070
Original Poster
QuoteOriginally posted by marcusBMG Quote
Do you get sharp pics close up?



Your terminology is off here. Normally a screw mount lens is the ubiquitous M42 thread, used by a number of camera/lens manufacturers inc Asahi Pentax. Is that the mount? And if it is what adapter are you using on the camera? You will lose focus with a rimmed adapter exactly like the pic. see here
There is no adapter. The lens I have is a K-type mount. I was trying to make sure that people would understand that, while I can find no reference to a Kalt 28mm with a K mount, that's what I have in hand. I found multiple references to a Kalt with the M42 screw mount.

Kozlok, it does do things better close up, here's a couple pictures I just took;

My watch, with an F-stop of 5.6;

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0647_zpsb5da3f83.jpg

My kit lens, with an F-stop of 2.8;

http://i1172.photobucket.com/albums/r571/djronnebaum/Kalt%2028mm/IMGP0650_zpsfd7c9076.jpg

04-27-2014, 05:01 PM   #5
Pentaxian
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 10,875
Make sure that it actually stops down to the selected aperture when you take the exposure.
also, you can dismount the lens and shine a flashlight down to see how clear it is, if it has any visible problems.
04-27-2014, 05:14 PM   #6
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
You can't use Av mode with a K mount lens that doesn't have A contacts, the lens doesn't stop down. You must use M mode and the green button.
04-27-2014, 05:24 PM   #7
Veteran Member




Join Date: Sep 2006
Location: Mississippi, USA
Photos: Gallery
Posts: 572
Looks like the results I got with a Soligor 28mm f2.8. I use mine as a Paper Weight now.
Bad lens is a bad lens.
04-27-2014, 06:17 PM   #8
Site Supporter
Site Supporter




Join Date: Jan 2014
Location: West Haven, CT USA
Photos: Albums
Posts: 1,070
Original Poster
QuoteOriginally posted by elliott Quote
You can't use Av mode with a K mount lens that doesn't have A contacts, the lens doesn't stop down. You must use M mode and the green button.
I'm aware. I'm using the aperture ring which does affect the blades. There's a difference in pictures taken at various f stops. I shot the house picture in auto just to let the body deal with iso and exposure. I can play more with it but responses here aren't encouraging.

04-27-2014, 06:31 PM   #9
Pentaxian
aleonx3's Avatar

Join Date: Jul 2007
Location: Brampton, Ontario
Photos: Gallery | Albums
Posts: 3,888
QuoteOriginally posted by pres589 Quote
I'm aware. I'm using the aperture ring which does affect the blades. There's a difference in pictures taken at various f stops. I shot the house picture in auto just to let the body deal with iso and exposure. I can play more with it but responses here aren't encouraging.
Sounds like it has been modified as K-mount but without the lever (so it functions similar to modified m42 without A/M switch). It appears to me that you can try to do AF adjustment on the camera. Try to do the adjustment test with something closer so you can tell whether it is FF or BF, hopefully you will find the adjustment work within the +/-10 range. Good luck...
04-27-2014, 07:21 PM   #10
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
QuoteOriginally posted by pres589 Quote
I'm aware. I'm using the aperture ring which does affect the blades. There's a difference in pictures taken at various f stops. I shot the house picture in auto just to let the body deal with iso and exposure. I can play more with it but responses here aren't encouraging.
The one with the kit lens at f11 is 1/100s, the one with the 28 is 1/2500, that 28 was wide open and not at f11 regardless of what the ring was set on. When not mounted you can turn the aperture ring and it will move the blades, but once you mount it the lens is held wide open with the aperture lever. In Av mode the camera is not going to release the aperture lever to allow the lens to stop down.

I can see this clearly in the EXIF, you were using Av mode, you can't use Av mode with that lens.

For f2.8 that doesn't look terrible, by f5.6 it should look pretty good.

EDIT: Looking again, even in M mode it is not going to work properly right now. That mount is non-conductive and not shorting the contacts of the camera mount. The camera think it is an M42 lens, it is not going to try to release the aperture lever. You need to short the contacts for it to work, either by adding some foil or removing the anodizing from the mount. It says "M42 or no lens" in the EXIF, it should say "K, M lens".

Last edited by elliott; 04-27-2014 at 07:32 PM.
04-27-2014, 07:47 PM   #11
Site Supporter
Site Supporter




Join Date: Jan 2014
Location: West Haven, CT USA
Photos: Albums
Posts: 1,070
Original Poster
elliot: Whoa, ok, thank-you! I'll look for instructions on where to remove the anodizing to properly mod the lens mount.
04-28-2014, 01:47 AM   #12
Senior Member




Join Date: May 2013
Posts: 140
take a small strip of aluminum foil to shorten the contacts of the mount on the camera before putting the lens on. i'm doing the same with an old porst lens that is non conductive as well.
04-28-2014, 07:20 AM   #13
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 1,553
Its just the data contact that needs to be shorted - thats the one at the half past six position ie the bottom end one as you're looking at the camera mount,

T-mounts have similar issues but work in Av mode without restriction because there is no aperture lever. There are a few lenses out there with black K-mounts, they typically date from the mid seventies, just when the K-mount was introduced.
Another simple possibility: try the lens not fully mounted ie turn it back from its position fully on with the locking pin clicked in (but not so much that it falls off!). This disengages the aperture lever.

Note that both using foil, and partially mounting the lens, can introduce mirror flopping issues!

The poor iq could be:
- simply the lens is rubbish wide open
- there is an optical fault like a loose element, incorrect repair reassembly, collimation out....
- there are focus issues
Some more diligent testing can help to establish what. eg set up on a tripod, use a page of news print on a wall, do test pics through the range of f stops. Set on f2.8, infinity focus, and walk to the the page using live view, noting if at a certain distance the page comes into focus.
04-28-2014, 07:46 AM   #14
Site Supporter
Site Supporter




Join Date: Jan 2014
Location: West Haven, CT USA
Photos: Albums
Posts: 1,070
Original Poster
marcusBMG: The back side of the mount, where the lens touches those contacts, is indeed black and seems like paint or a similar coating. I have the lens marked as to where I need to hit it with a little sand paper (I don't like the idea of using foil there, which I know would work electrically, but could fall into the body or something else happen; I'd rather sand on a cheap lens then potentially damage a body that cost me $600). The aperture ring is definitely having no effect on pictures; took a low light shot at F2.8 and then again at F16 and they look pretty much the same. I'm not sure why I didn't notice this earlier... Thankfully this isn't part of my day job.

When I get a chance I'll see what I can do with the newsprint test.
04-28-2014, 08:52 AM   #15
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 1,553
QuoteOriginally posted by pres589 Quote
I have the lens marked as to where I need to hit it with a little sand paper
Remember you need to make a circuit so in that case I would take off the paint for ALL the contacts. Thats what I did on a T-mount. I made a mask by making a pencil rubbing of paper held onto the camera mount used that to scratch the positions and then used a dremel bit by hand to take off the anodising. But TBH the connection is iffy. For testing use foil: fold a small piece into an oblong shape about 1/4" by 1/2", use a finger/thumb to hold in position as you mount the lens. Also try partially mounting as suggested, quickest and easiest.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
bit, camera, focus, fullsize, kalt, lens, lenses, old manual lens, pentax, pentax help, shot, steve, vivitar
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pets Well, what is it? What do you want from me? I am just a mere kat. rrstuff Post Your Photos! 6 02-17-2014 08:37 PM
Nature This guy never gives up. What type of spider is it. charliezap Post Your Photos! 11 09-03-2013 06:11 PM
K30 mirror up, what is there, should it be like this? Danas_Anis Pentax K-30 & K-50 3 07-13-2013 02:46 PM
Help me guess what lens this is? Julie Pentax SLR Lens Discussion 6 02-26-2013 10:14 AM
is it me, or the K5..guess what..its me !!! Tommot1965 Pentax K-5 18 01-28-2011 02:35 AM



All times are GMT -7. The time now is 12:00 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top