Help with a Zenitar 4.5/300

mano · 12-18-2010, 04:57 AM

I just received a used Zenitar 4.5/300 from an Ebay purchase and I'm pretty sure I have been sent a damaged lens. The aperture just isn't working!

I've handled fully manual lenses before (got my first SLR in the '80s) but never a K-Mount so I'd like to make sure I'm not making an ass of myself.

When not connected to the camera the aperture should open and close when I turn the aperture ring, right? With this lens the aperture stays open, no matter what. The lever on the mount by which the aperture is opened/closed by the camera also does nothing and is suspiciously loose.

Of course it is impossible to shoot with the lens, as the aperture is also always at max when connected to the camera.

So, should I write an impolite email to the seller or am I overlooking something obvious?

Stringmike · 12-18-2010, 09:29 AM

... but don't be too mean to the seller up front - damage could have occurred in shipping.

Mike

omega leader · 12-18-2010, 10:01 AM

Could it be possible this is a two step apature lens? There are some lenses (especially old Russian) where your apature dial sets the dial, but then you have to use another button or ring to actually stop the lens down?

Just a thought.

**boriscleto** · 12-18-2010, 10:21 AM

Sounds like oil on the blades. Jiggle the aperture lever, sometimes that unsticks the blades. Otherwise it has to be opened and cleaned.

mano · 12-18-2010, 11:02 AM

Thanks for all the answers so far!

Originally posted by Stringmike

... but don't be too mean to the seller up front - damage could have occurred in shipping.

Don't worry, I was exaggerating.

I usually don't get nasty when not really provoked.

Originally posted by omega leader

Could it be possible this is a two step apature lens? There are some lenses (especially old Russian) where your apature dial sets the dial, but then you have to use another button or ring to actually stop the lens down?

Just a thought.

Interesting, I had never heard about that. Don't think that's the case though, at least I can't find another button. Still good to keep that in mind when contacting the seller, thanks!

Originally posted by boriscleto

Sounds like oil on the blades. Jiggle the aperture lever, sometimes that unsticks the blades. Otherwise it has to be opened and cleaned.

I don't think the lever is doing anything when I move it, it does not seem to be connected to anything anymore.

I'm thinking about asking the seller for a partial refund and trying to fix the lens. An interesting project for the upcoming vacation if nothing else... How much would you be willing to pay for a lens like this with a mechanical defect? All in all the lens feels really solid.

xjjohnno · 12-19-2010, 01:03 AM

What mount does it have?
If M42 is there a pin at the base of the mount as the pin will activate the aperture mechanism. If the aperture control is at the front of the lens then a second ring usually acts as the aperture control.

mano · 12-19-2010, 12:18 PM

The lens has a K-mount. The aperture ring is is at the base of the lens. Looks all pretty standard to me.

I also just got an answer from the seller. He never tested the thing before putting it on ebay, and has never actually used it!

So I assume it is broken, but I'll ask for a partial refund and either try to fix it myself or ask at the only remaining local camera store. This lens really looks interesting.

12-18-2010, 04:57 AM	#1
mano Senior Member Join Date: Aug 2010 Posts: 151	Help with a Zenitar 4.5/300 I just received a used Zenitar 4.5/300 from an Ebay purchase and I'm pretty sure I have been sent a damaged lens. The aperture just isn't working! I've handled fully manual lenses before (got my first SLR in the '80s) but never a K-Mount so I'd like to make sure I'm not making an ass of myself. When not connected to the camera the aperture should open and close when I turn the aperture ring, right? With this lens the aperture stays open, no matter what. The lever on the mount by which the aperture is opened/closed by the camera also does nothing and is suspiciously loose. Of course it is impossible to shoot with the lens, as the aperture is also always at max when connected to the camera. So, should I write an impolite email to the seller or am I overlooking something obvious?

12-18-2010, 09:29 AM	#2
Stringmike Senior Member Join Date: Jul 2008 Location: Arizona Posts: 283	Sounds like mechanical link problem... ... but don't be too mean to the seller up front - damage could have occurred in shipping. Mike

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12-18-2010, 10:01 AM	#3
omega leader Veteran Member Join Date: Jan 2008 Location: Niagara Region, Ontario Canada Photos: Gallery Posts: 417	Could it be possible this is a two step apature lens? There are some lenses (especially old Russian) where your apature dial sets the dial, but then you have to use another button or ring to actually stop the lens down? Just a thought.

12-18-2010, 10:21 AM	#4
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Sounds like oil on the blades. Jiggle the aperture lever, sometimes that unsticks the blades. Otherwise it has to be opened and cleaned.

12-18-2010, 11:02 AM	#5
mano Senior Member Join Date: Aug 2010 Posts: 151 Original Poster	Thanks for all the answers so far! Originally posted by Stringmike ... but don't be too mean to the seller up front - damage could have occurred in shipping. Don't worry, I was exaggerating. I usually don't get nasty when not really provoked. Originally posted by omega leader Could it be possible this is a two step apature lens? There are some lenses (especially old Russian) where your apature dial sets the dial, but then you have to use another button or ring to actually stop the lens down? Just a thought. Interesting, I had never heard about that. Don't think that's the case though, at least I can't find another button. Still good to keep that in mind when contacting the seller, thanks! Originally posted by boriscleto Sounds like oil on the blades. Jiggle the aperture lever, sometimes that unsticks the blades. Otherwise it has to be opened and cleaned. I don't think the lever is doing anything when I move it, it does not seem to be connected to anything anymore. I'm thinking about asking the seller for a partial refund and trying to fix the lens. An interesting project for the upcoming vacation if nothing else... How much would you be willing to pay for a lens like this with a mechanical defect? All in all the lens feels really solid.

12-19-2010, 01:03 AM	#6
xjjohnno Veteran Member Join Date: Jan 2009 Location: Melbourne Australia Photos: Gallery Posts: 2,115	What mount does it have? If M42 is there a pin at the base of the mount as the pin will activate the aperture mechanism. If the aperture control is at the front of the lens then a second ring usually acts as the aperture control.

12-19-2010, 12:18 PM	#7
mano Senior Member Join Date: Aug 2010 Posts: 151 Original Poster	The lens has a K-mount. The aperture ring is is at the base of the lens. Looks all pretty standard to me. I also just got an answer from the seller. He never tested the thing before putting it on ebay, and has never actually used it! So I assume it is broken, but I'll ask for a partial refund and either try to fix it myself or ask at the only remaining local camera store. This lens really looks interesting.