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06-26-2011, 04:42 AM   #31
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X-posted from street photography thread.

07-22-2011, 05:29 AM   #32
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Enjoying using the Super-Wide with my K1000. I'll post some pictures soon when I've developed the film. It's so wide on 35mm... I now find myself wanting a DA15 Ltd for my K10D.

Is there any chance we can get a Super-Wide lens club thread going?
07-22-2011, 07:42 AM   #33
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QuoteOriginally posted by jeztastic Quote
Is there any chance we can get a Super-Wide lens club thread going?
I'd advocate enthusiastic posting to the Sigma Lens Club.
07-29-2011, 06:05 AM   #34
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Pentax K1000 and Sigma 24mm 2.8 Super-Wide II. The lens in all it's wide angle glory. I actually love the blue sky colours I got on film from this...

10-18-2011, 01:37 PM   #35
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Metering with this lens and Pentax K2000(km)

Hello,
please can you tell me, what settings I must set on Pentax K2000(Km in Europe) to get correctly exposed picture from this lens? I have on the lens aperture ring A (automatic), on the camera, I have A (on PASM button), so I can set the aperture from the camera. But, unfortunately, when I have metering mode point, or accented center, or the third possibility and I use anything other then F2.8, the photography is badly exposed (too bright). When I set F4, photography is bright, when set F8, photography is more brighter then F4.

It is very big limitation for me. I donīt shoot only at F2.8 and fully manual mode is slowly for me, but works propertly. I set the aperture on the lens, on the camera M (manual), then push Av button and the aperture goes to set possition, Ae metering finds the correct exposition and then shoot. But this lens must works at Aperture mode with this camera, If I read the specifications of K-A mount propertly...

Can you help me?
10-18-2011, 02:21 PM   #36
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Sounds like you have a faulty lens. Sorry, your English makes it hard to work out exactly what you mean. Do you mean the lens works, unless you set it to 'A'?
10-18-2011, 03:01 PM   #37
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Whatever the reason is, you first have to find out whether the camera is able to close the aperture. There are several ways to find out. I suggest to set the lens to some smaller aperture (could be 8 or 11, in any case not "A" and not 2.8) and the camera to manual mode. Then either use the stop down feature or the DOF control. If you don't know how to do this, have a look at the manual - I don't own a KM/K2000. The viewfinder should darken when you do so. If not, the camera IS NOT ABLE to control the aperture of this lens, most likely a mechanical fault. If this works alright with other lenses, the lens is the culprit. If the viewfinder darkens for a moment, as it should, we have to start another investigation.
10-18-2011, 03:23 PM   #38
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Analysing your initial posting more carefully, it now seems to me you have done tests similar to my suggestion by using the "M" mode. If this assumption is correct, and stop down metering ("push Av button" ?) works OK, obviously the camera recognizes the lens wrongly as K-mount, not a KA-mount. Try to find out whether the contacts at the lens and camera mount are OK.

If you are posting from home, we are in the same time zone; I may stop now, as it's half past midnight. I'll have another look at this thread tomorrow. Maybe our american friends have additional or better advice, there it is only late afternoon to early evening.


Last edited by RKKS08; 10-18-2011 at 03:45 PM.
10-18-2011, 06:11 PM   #39
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Also try taking the lens off the camera. Set the aperture to f8, then move the lever with your finger. You should be able to see the aperture blades move. If the do move, then the problem is with the 'A' setting on the lens. This lens is difficult to get in the 'A' position. Make sure you push the little button in hard, you need to be rough with it.

If none of this works, then do what RKKS08 says...
10-18-2011, 10:48 PM   #40
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Sorry for my English
When I try to move with lever on the lens, aperture blades are moving smoothly.
"("push Av button" ?) " = "Av" button is on Km button for DOF control (next PASM roller). When I try to push it, aperture goes on set position (viewfinder darken) (in Manual mode) and exposition metering make the measurement correctly.

So lens is ok, I think. Problem is, that camera canīt set the correct aperture in A mode. Contacts on the lens seems to be allright.
10-19-2011, 08:33 AM   #41
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I can see only 2 possibilities:

  1. The lens maybe correctly set to "A" mode, but for some reason the camera is not detecting you are using a PK/A lens. Now, if the camera is in "A" mode, it does not use the possibility to set aperture when shooting.
  2. The "A" setting of the lens does not work; either a fault or misalignment of the lens mechanics. In this case in "A" mode (of the lens) you will always shoot with fully opened aperture. With camera and lens set to "M" it is handled as a PK lens, and stop down metering works as it should.
Another idea about the lens contacts:

Till the introduction of the Pentax Z/ZX series, Sigma (and some other 3rd party lens manufacturers) used a protecting shield for the aperture lever which was much bigger and in a slightly different position than with the Pentax lenses. When Pentax started the Z/ZX series with its support for power zoom, they added a small box with contacts for voltage supply of the power zoom motors (with some newer DSLRs, these contacts supply SDM lenses with voltage). This box and its contacts are either touching the lever protecting shield of the lens, or even preventing from attaching the lens. I once had to return a Sigma Mini Wide II for that reason. In some other thread of this forum a member told he just had to use some force when he attached the lens for the very first time, after that everything worked OK. I would rather think he just bent something inside the camera, so now the lens fits! If your lens is an unmodified item of this series (Sigma later modified the design), and the protecting shield touches the contacts of that box, it could keep the lens just a fraction of a millimeter from its normal position, causing worse contact between lens and body. Maybe that sounds far-fetched, but nevertheless I think it is worth a check.

Last edited by RKKS08; 10-19-2011 at 09:04 AM.
10-19-2011, 10:46 AM   #42
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1. I think, that camera knows, that Iīm using PK/A lens, because when I set A mode (on camera) and A mode on lens, my camera allow to set the aperture and calculate time (wrong time at higher f number). When I tried unmount the lens from camera (camera was turned on), the aperture setting on display came to "---". So camera know, that lens was unplugged.
Lens have only two contacts, both looks allright.
2. "A" setting of the lens works (my opinion), but camera do not move with the aperture lever (SW problem?).
10-20-2011, 10:56 AM   #43
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If your statement (1) is correct, the camera indeed recognizes the lens as a PK/A. Now, what is the difference in moving the aperture lever with the lens set to "A" or to an aperture value?

  1. If a PK/A lens is set to an aperture value at the lens (or the lens is recognized as a PK lens), the camera will try to move the lever all the way through. The lens itself is mechaniclly limiting the closing of the aperture according to the set value.
  2. If the camera recognizes the lens as a PK/A type (set to "A" at the lens), the camera processor will calculate a limited move of the lever. This calculation is based on a linear mapping of the mechanical limits of the lever to the aperture value limits of the lens. The limits of the lever are fixed values, given by the Pentax design of the PK/A mount. The limits of the aperture can be asked for by the camera - there is a passive matrix inside the lens, connected to the contacts. The bit code of the electrical resistance between the contacts and/or contact to mount tells the aperture limits of the lens.

I think the camera must somehow get values which are not fitting to that lens. Such an error - no matter whether caused by faults inside the lens, at the contacts, or somewhere on the communication path - would have no consequences for shooting in "M" mode (as long as you set aperture at the lens, not from camera). But it could cause all kinds of weird behaviour in any mode where the camera tries to actively control the aperture.

I think I am now running out of ideas - the very best solution would be a cross check: try the lens at another Pentax body, and try another PK/A lens at your camera body. You should prefer a true "A" lens: F, FA, DA and DFA lenses may provide additional active electronic circuits instead of mearly resistors, and this could make it difficult to draw conclusions.

Last edited by RKKS08; 10-20-2011 at 11:05 AM.
10-22-2011, 07:19 AM   #44
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How much focus travel do these lenses have?
Been considering one for video work so the more precise the focus pulling the better.
10-22-2011, 07:52 AM   #45
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I was actually talking about the manual version.
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