Exchange rear mount of the len ?

stevewong · 02-05-2015, 07:56 PM

Hello to all,
I have two lens. FA 100- 300 F4.7-5.8 and F 80-200 F4.7- 5.6 . The FA does not have Rear Metal Mount. But the F len has Metal mount.
I like FA color and more reach !!. Fa has Plastic rear mount.
Thanks,
steve

**sergysergy** · 02-05-2015, 09:29 PM

If both are working properly I do not know why you would want to do that.

Not a Number · 02-05-2015, 09:37 PM

I take it the OP would rather use the FA than the F and would rather have a sturdier metal mount on a lens he prefers using.

There are a post or two on swapping out plastic mounts for metal. There was something you had to do like cutting an insulator or connector on the pins on the plastic mount for the lens to communicate properly with a metal mount installed. I don't recall the details, you'll have to use the search function to find the actual posts.

**jatrax** · 02-05-2015, 10:36 PM

Originally posted by stevewong

Hello to all, I have two lens. FA 100- 300 F4.7-5.8 and F 80-200 F4.7- 5.6 . The FA does not have Rear Metal Mount. But the F len has Metal mount. I like FA color and more reach !!. Fa has Plastic rear mount.

Steve there are a few posts on the forum about doing this. It is not trivial but anyone comfortable with small tools and parts can do it provided the two lenses use the exact same mount connections.

However, what is the problem with the plastic mount? It is functionally the same as the metal one.

bassek · 02-06-2015, 02:13 AM

A plastic mount on the lens ensures that the camera (metal) mount stays intact if the camera is dropped. In addition it does not wear the camera mount as much.
So for a cheap lens I would not bother.

Seb

stevewong · 02-06-2015, 04:46 AM

Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!.
steve

arkav · 02-06-2015, 05:43 AM

Originally posted by stevewong

Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!.

Unless you think the F series lens is truly worthless, it might be better to leave it as is. It might be better to look around for someone who is selling a cheap/broken lens with the metal mount.

**jatrax** · 02-06-2015, 10:18 AM

Originally posted by stevewong

Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!.

In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses.

As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks.

stevewong · 02-06-2015, 10:58 AM

Originally posted by jatrax

In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses.

As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks.

Thanks jatrax,
I will keep it as it.
steve

**yucatanPentax** · 02-06-2015, 11:11 AM

Originally posted by jatrax

In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses.

As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks.

I really agree with this. Removing the mounts with the electronic contacts, etc, isn't as simple as an old manual focus, manual aperture lens. I've never heard of a plastic mount wearing out. And why create a less than factory-quality electrical contact when not necessary?

But for argument's sake, let's say that the mount does eventually wear out. That's the point at which I'd consider swapping in a metal mount (from a scrap or broken lens), rather than mess with success while all is currently functioning properly.

Just my thoughts on it, Your mileage may vary.

Not a Number · 02-06-2015, 11:47 AM

Originally posted by jatrax

It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses.

There was discussion on one of the Yahoo manual focus lens groups on the plastic mount of Nikon kit lenses failing after a year or two of use, usually after the warranty expiring. As it turned out it seems Nikon's warranty doesn't cover the plastic mount any way.

**jatrax** · 02-06-2015, 11:55 AM

Originally posted by Not a Number

There was discussion on one of the Yahoo manual focus lens groups on the plastic mount of Nikon kit lenses failing after a year or two of use, usually after the warranty expiring. As it turned out it seems Nikon's warranty doesn't cover the plastic mount any way.

One more reason to buy Pentax

02-05-2015, 07:56 PM	#1
stevewong Senior Member Join Date: Jul 2013 Posts: 215	Exchange rear mount of the len ? Hello to all, I have two lens. FA 100- 300 F4.7-5.8 and F 80-200 F4.7- 5.6 . The FA does not have Rear Metal Mount. But the F len has Metal mount. I like FA color and more reach !!. Fa has Plastic rear mount. Thanks, steve

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02-05-2015, 09:29 PM	#2
sergysergy Site Supporter Join Date: Jan 2011 Photos: Gallery Posts: 5,170	If both are working properly I do not know why you would want to do that.

02-05-2015, 09:37 PM	#3
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	I take it the OP would rather use the FA than the F and would rather have a sturdier metal mount on a lens he prefers using. There are a post or two on swapping out plastic mounts for metal. There was something you had to do like cutting an insulator or connector on the pins on the plastic mount for the lens to communicate properly with a metal mount installed. I don't recall the details, you'll have to use the search function to find the actual posts.

02-05-2015, 10:36 PM	#4
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Originally posted by stevewong Hello to all, I have two lens. FA 100- 300 F4.7-5.8 and F 80-200 F4.7- 5.6 . The FA does not have Rear Metal Mount. But the F len has Metal mount. I like FA color and more reach !!. Fa has Plastic rear mount. Steve there are a few posts on the forum about doing this. It is not trivial but anyone comfortable with small tools and parts can do it provided the two lenses use the exact same mount connections. However, what is the problem with the plastic mount? It is functionally the same as the metal one.

02-06-2015, 02:13 AM	#5
bassek Pentaxian Join Date: Feb 2011 Photos: Gallery Posts: 706	A plastic mount on the lens ensures that the camera (metal) mount stays intact if the camera is dropped. In addition it does not wear the camera mount as much. So for a cheap lens I would not bother. Seb

02-06-2015, 04:46 AM	#6
stevewong Senior Member Join Date: Jul 2013 Posts: 215 Original Poster	Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!. steve

02-06-2015, 05:43 AM	#7
arkav Veteran Member Join Date: Jul 2009 Location: Ottawa, Canada Posts: 366	Originally posted by stevewong Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!. Unless you think the F series lens is truly worthless, it might be better to leave it as is. It might be better to look around for someone who is selling a cheap/broken lens with the metal mount.

02-06-2015, 10:18 AM	#8
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Originally posted by stevewong Thanks to all who have post to my question !. Both lens are working fine. I use the FA Zoom more than F len.I like the Metal mount so i think it may not be difficult to change out ....But i may use it for now until the Plastic mount broke !!!!. In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses. As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks.

02-06-2015, 10:58 AM	#9
stevewong Senior Member Join Date: Jul 2013 Posts: 215 Original Poster	Originally posted by jatrax In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses. As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks. Thanks jatrax, I will keep it as it. steve

02-06-2015, 11:11 AM	#10
yucatanPentax Loyal Site Supporter Join Date: Dec 2009 Location: Dallas / Yucatan Posts: 1,840	Originally posted by jatrax In the almost 5 years that I've been on this forum I remember only two posts about broken plastic mounts and both of those were drops that likely would have broken a metal mount as well, or worse damaged the camera mount. It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses. As noted above a plastic mount provides a point failure for potential damage, breaking before the camera mount. In addition it does not scratch up the camera as much as a metal one. There is no reason to swap the mount unless it breaks. I really agree with this. Removing the mounts with the electronic contacts, etc, isn't as simple as an old manual focus, manual aperture lens. I've never heard of a plastic mount wearing out. And why create a less than factory-quality electrical contact when not necessary? But for argument's sake, let's say that the mount does eventually wear out. That's the point at which I'd consider swapping in a metal mount (from a scrap or broken lens), rather than mess with success while all is currently functioning properly. Just my thoughts on it, Your mileage may vary.

02-06-2015, 11:47 AM	#11
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Originally posted by jatrax It is a complete myth that they are any less reliable than metal mounts at least for light weight lenses. There was discussion on one of the Yahoo manual focus lens groups on the plastic mount of Nikon kit lenses failing after a year or two of use, usually after the warranty expiring. As it turned out it seems Nikon's warranty doesn't cover the plastic mount any way.

02-06-2015, 11:55 AM	#12
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Originally posted by Not a Number There was discussion on one of the Yahoo manual focus lens groups on the plastic mount of Nikon kit lenses failing after a year or two of use, usually after the warranty expiring. As it turned out it seems Nikon's warranty doesn't cover the plastic mount any way. One more reason to buy Pentax