Focussing problem on Sigma 10-20/4-5,6 lense for Pentax

some of the older sigma 70 -500 lenses had a little rubber belt driving the focussing. you can access this by removing the mount ring, four screws and two on recessed on the side holding the contact also three screws holding the centre black cover. the belt used to stretch therefore no longer driving the focussing ring.

What is the focussing problem?
The EOS 7d is usually an autofocus camera with a 19-point
focussing system.
Are you trying to override the focus manually?
This is not recommended.
Much of the purchase price is based on the speed and
accuracy of the focus.
Please restate your problem with more detail and information.

Only Pentax DA and FA J lenses and D FA/FA/F/A lenses having an "A" position on the aperture ring can be used with this camera.

The lens you have is HSM DG

What do you mean by close range?
All lenses have range within which objects can be focussed. Objects within the "closest focussing distance" cannot be focussed. The maximum is usually infinity. Yours lens specification should tell you what the "closest focussing distance" is.

You have just two choices then as it is not a DIY repair:-

1. Live with it until you decide to upgrade to a better lens;

2. Send it to Sigma for repair.

If you choose the second option, then if you're in the UK Sigma have a fixed price servicing menu, your repair would cost £93.99 on tariff no.6. Pretty cheap compared to a new lens, but expensive compared to just turning the focussing ring on an otherwise good lens.

The choice is yours...

I hope that you have found my answer to be of use, if so then please take a moment to rate it.

Which exact lenses are you trying to use? The N2000 (aka F301) is a manual focus camera so if you're trying to use autofocus lenses you have to focus them manually. Sorry if this seems an insulting suggestion, but you did state "my camera will not focus" and I've learned that on FixYa it's best not to assume any prior level of knowledge with regard to those who post questions.

The next thing to check is whether the viewfinder has an eyecup attached, if so slide it upwards to remove it as sometimes they have a corrective lens fitted if the previous user needed corrective optics. If your vision is fine (with glasses/contact lenses if necessary) then a corrective lens on the viewfinder may make things look blurry.

Other than that, the only other possible cause (other than a pair of broken lenses) is if the focussing screen has become dislodged downwards (or somehow fitted upside-down) then the viewfinder image will be unsharp. Officially the F301/N2000 had a fixed focussing screen but it could be replaced with one of three designed for the higher specified F501 (which does have autofocus), and if not seated correctly you'd get the focussing issue you describe.

You can test if the focussing screen is the problem in one of two ways:-
1. A visual inspection (you may need to get a more experienced photographer to take a look at it);

2. Set the lens to focus at infinity and at the widest possible aperture and take a photograph of a distant object (ignoring the blurred viewfinder). process the film and inspect the photo. If it's sharp then you have a focussing screen problem. If not, then it's a lens problem.

If the problem is a poorly fitted focussing screen then it may just need reseating or to be removed and refitted. It's vital to do this in a dust free environment and to avoid getting fingerprints on the screen. Some screens sit in a hinged frame which then clips into place when pushed up, others push into a pair of clips towards the top rear and then the front is held in place by a spring clip: it's been a long while since I worked on the F501 or F301 so I don't recall which system is used.

Courtesy of Norman Butkus' website, click here for a free Nikon N2000 user manual.

I hope that you've found my answer to be of use, if so please return the favour by rating my answer.

You need to send it back to a sigma agent

If u used to have a Pentax camera, i would recommend you buying a Pentax DSLR, because Pentax film lenses still works on Pentax DSLR. I still use some of my prime lenses on my K10D.

Found this myself check manual focus ring (closest to camera) maybe ring has moved to "manual"position. This ring moves backwards and forwards between "manual" and "auto" and may need pushing home completely

Hello,

I don't own a K10D, but I do own a K100D which I have successfully used both manual focus & auto-focus lenses from my old Pentax stash!

1) If it is a manual focus lens, you need to turn off Autofocus on the body of your K10D. On my K100D, there is a switch on the side of the lens mount that says [-MF or -AF]. "-MF" is manual focus mode & "-AF" is autofocus mode. Since your lens doesn't have autofocus capability, turn it to the "-MF" mode.

Also . . . When I press "Menu" and go to "Custom Setting", I change two settings . . .

1) I change "Using aperture ring" to "Permitted". This allows you to use manual lenses (M lenses) that do not have an auto(exposure) setting, and also lets you use Auto lenses (A, KA, KA2, FA, etc.) in either the Auto or manual aperture setting modes.

2) I change "Fl with S lens used" so that even with a manual focus lens, although I don't have autofocus capability, my K100D beeps and shows a little red square in the viewfinder when I have successfully focused manually!

The K10D should have the same options.

This should get you up and running!

I have had a load of fun with my old lens on my new digital Pentax!

Take care & Happy Imaging!
Glen
:)