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**ismaelg** · 06-28-2010, 12:54 PM

Hi,

As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference.
I suspect my A50 f1.7 is controlling my mind....

Shhh, I just heard it calling me..... gotta go!

Thanks,

dgaies · 06-28-2010, 01:28 PM

Originally posted by ismaelg

Hi,

As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference.
I suspect my A50 f1.7 is controlling my mind....

Shhh, I just heard it calling me..... gotta go!

Thanks,

They are optically identical. Here's a link that talks about the them.

SOldBear · 06-28-2010, 01:33 PM

I at one point had 3 copies of the F50 F/1.7 and a copy of the FA50 F/1.7.

IQ-wise, I couldn't tell the difference. I just happen to prefer the look of the FA to that of the F, so I sold all the Fs.

creampuff · 06-28-2010, 07:38 PM

Biggest difference is the dated look and the thin, hard plastic focusing ring of the F version. I've seen quite a few F versions where the edges surrounding the distance window start to peel away. Perhaps these lenses are already showing their age.

Pentaxor · 06-28-2010, 07:43 PM

the only difference is the body.

**Aristophanes** · 06-28-2010, 07:54 PM

Originally posted by ismaelg

Hi,

As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference.
I suspect my A50 f1.7 is controlling my mind....

Shhh, I just heard it calling me..... gotta go!

Thanks,

The letter A.

atiratha · 06-28-2010, 10:45 PM

The main difference is in what the CPU transmits to the body. It is my understanding that the F series does transmit only very rudimentary MTF information (even this is a marcel considering there was no body to make use of this data at the time)

Eruditass · 06-28-2010, 10:48 PM

The F series is slightly easier to manual focus with one finger. Despite the thinner ring, there are notches in it.

bdery · 06-29-2010, 05:08 AM

I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ.

I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens.

pb_red · 06-29-2010, 11:47 AM

i've used the F 1.7 in both auto-focus mode for photos and manual focus for video and both work very well.

i will hate myself afterward but i think i will end up selling my copy for something wider... nothing against the lens just that i prefer wider angle shots.

Eruditass · 06-29-2010, 12:23 PM

Originally posted by bdery

I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ.

I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens.

I've never used only Manual focus, but I do use pseudo-quick-shift by pushing the lens release button (and I have only the AF button for AF, not the half-press)

Blue · 06-29-2010, 01:34 PM

Originally posted by bdery

I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ.

I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens.

Damn! There must be something wrong with the AF on my SuperProgram.

bdery · 06-30-2010, 04:57 AM

Originally posted by Blue

Damn! There must be something wrong with the AF on my SuperProgram.

There might be. My F50 f1,7 is my most reliable AF lens. Faster than the FA50 macro (which also doesn't miss often) or the DA 21 LTD. And always spot on. When all things fails, I hook that lens on my camera, and start shooting again. That's why I own it.

dragonfly · 06-30-2010, 09:36 AM

I can't access the lens correction menu in my K-x with the F50 1.7. I don't know if it's available with the FA50

Eruditass · 06-30-2010, 10:13 AM

Originally posted by dragonfly

I can't access the lens correction menu in my K-x with the F50 1.7. I don't know if it's available with the FA50

I don't think they're talking about the lens correction, but MTF information (for K20D and K-7's MTF program line)

06-28-2010, 12:54 PM	#1
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,685	What's the difference between F and FA series 50mm f1.7? Hi, As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference. I suspect my A50 f1.7 is controlling my mind.... Shhh, I just heard it calling me..... gotta go! Thanks,

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06-28-2010, 01:28 PM	#2
dgaies Veteran Member Join Date: Oct 2009 Location: Maryland / Washington DC Posts: 3,917	Originally posted by ismaelg Hi, As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference. I suspect my A50 f1.7 is controlling my mind.... Shhh, I just heard it calling me..... gotta go! Thanks, They are optically identical. Here's a link that talks about the them.

06-28-2010, 01:33 PM	#3
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	I at one point had 3 copies of the F50 F/1.7 and a copy of the FA50 F/1.7. IQ-wise, I couldn't tell the difference. I just happen to prefer the look of the FA to that of the F, so I sold all the Fs.

06-28-2010, 07:38 PM	#4
creampuff Veteran Member Join Date: May 2007 Location: Singapore Photos: Gallery Posts: 3,953	Biggest difference is the dated look and the thin, hard plastic focusing ring of the F version. I've seen quite a few F versions where the edges surrounding the distance window start to peel away. Perhaps these lenses are already showing their age.

06-28-2010, 07:43 PM	#5
Pentaxor Veteran Member Join Date: May 2009 Location: Vancouver, B.C. Photos: Gallery Posts: 6,513	the only difference is the body.

06-28-2010, 07:54 PM	#6
Aristophanes Site Supporter Join Date: Jul 2008 Location: Rankin Inlet, Nunavut Photos: Albums Posts: 3,948	Originally posted by ismaelg Hi, As posted elsewhere, I love my A50 f1.7 Since the AF counterparts are optically similar, I'm contemplating that. But other than cosmetics, what is the difference between F and FA series? (Specifically the 50mm f1.7) Other than the FA is very hard to find? I've searched in the lens database and Dimitrov page but I can't really find any difference. I suspect my A50 f1.7 is controlling my mind.... Shhh, I just heard it calling me..... gotta go! Thanks, The letter A.

06-28-2010, 10:45 PM	#7
atiratha Senior Member Join Date: Mar 2009 Photos: Gallery Posts: 121	The main difference is in what the CPU transmits to the body. It is my understanding that the F series does transmit only very rudimentary MTF information (even this is a marcel considering there was no body to make use of this data at the time)

06-28-2010, 10:48 PM	#8
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	The F series is slightly easier to manual focus with one finger. Despite the thinner ring, there are notches in it.

06-29-2010, 05:08 AM	#9
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,363	I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ. I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens.

06-29-2010, 11:47 AM	#10
pb_red Senior Member Join Date: Jan 2007 Location: Seattle Posts: 194	i've used the F 1.7 in both auto-focus mode for photos and manual focus for video and both work very well. i will hate myself afterward but i think i will end up selling my copy for something wider... nothing against the lens just that i prefer wider angle shots.

06-29-2010, 12:23 PM	#11
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by bdery I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ. I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens. I've never used only Manual focus, but I do use pseudo-quick-shift by pushing the lens release button (and I have only the AF button for AF, not the half-press)

06-29-2010, 01:34 PM	#12
Blue Moderator Site Supporter Join Date: Jun 2008 Location: Florida Hill Country Photos: Gallery \| Albums Posts: 17,377	Originally posted by bdery I've never needed to focus manually with my F50 f1,7. Never. Whatever the circumstances it will lock focus like a champ. I'd say get the cheaper one you can find, be it F or FA. I've also heard that some F have the plastic peel off in one spot, but my used copy is flawless. And the ffocus ring is indeed very easy to use, and it's pretty well damped for an AF lens. Damn! There must be something wrong with the AF on my SuperProgram.

06-30-2010, 04:57 AM	#13
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,363	Originally posted by Blue Damn! There must be something wrong with the AF on my SuperProgram. There might be. My F50 f1,7 is my most reliable AF lens. Faster than the FA50 macro (which also doesn't miss often) or the DA 21 LTD. And always spot on. When all things fails, I hook that lens on my camera, and start shooting again. That's why I own it.

06-30-2010, 09:36 AM	#14
dragonfly Veteran Member Join Date: Jun 2009 Location: on the wall Photos: Gallery Posts: 715	I can't access the lens correction menu in my K-x with the F50 1.7. I don't know if it's available with the FA50

06-30-2010, 10:13 AM	#15
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by dragonfly I can't access the lens correction menu in my K-x with the F50 1.7. I don't know if it's available with the FA50 I don't think they're talking about the lens correction, but MTF information (for K20D and K-7's MTF program line)

What's the difference between F and FA series 50mm f1.7?

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