[revdocjim]

I don't have any experience with the FA 35mm but have owned and used the A 35mm on my 645N for about a year now. I've been happy with it but can't give you any particular data to confirm it's performance. As for pricing, on the used market here in Tokyo the FA 35mm goes for about $1,000 and the A 35mm is about $460.

[jonojono]

Hi jonojo,
I just checked you existing equipment. No kidding, but you will never be happy with the FA35. If you want, I can send you full res files from a 35a.

I dont know. why do some love the 35A so much, while others vouch for the FA35?

[mazwick]

Hi there,
I try to explain this a bit.

Assumption: main focus is landscape photography

Lets start with non IQ differences

weight: the 35a (470g) is leighter than the 35FA (560g), not much but you feel it
size: the 35a is quite a bit smaller in size than the 35 FA
diameter: 35a 77mm 35FA 82mm. 82 is a bit unusual and it adds to the cost, a 82 highend polarizer with grey filters and so on will cost you 300-400 EUR, it is vey likely that you already have 77mm equipment

now the real important things

focusing: 35FA is AF, switched off manual focusing is not bad, the focus ring has nearly no play (quite good to be honest), but it moves very easily without feeling any resistance. It happens very often, that defocussing can happen just by chance, now the field curvature starts to play a major role. A slight movement away from the optimal focussing will have drastic impacts. The 35A is much much more tolerant. The focus ring is beautifully dampened, it has a natural resistance and the depth of field engarvings are much more accurate. Basically what I mean: focussing is much easier and much quicker. If you are used to high end focussing rings (Zeiss, Leica) you will like the 35A.

IQ related things:

Field curvature: I personally think that if you focus at infinity or "normal" hyperfocal distances the field curvature is hardly acceptable and very difficult to manage. You must know exactly where to focus using a certain aperture. At closer distance it is not as strong or not visible

Smaller apertures: this point goes to the 35FA. The 35A is very good up to 14, still good at 16 but deteriorates very quickly from 16 onwards. The 35FA is better at 16 and keeps a better quality from there on

Wide open: difficult to say, I do landscape and do not have to use the lenses wide open often. What I think is as following: the 35FA is a bit better wide open, but you cannot use this adavantage due to the field curvature

Sample variation: the 35FA shows a very high variation in quality, if you buy it, buy it at a good dealer! Take shots focussed at infinity, close to infinity, mid range and so on, always with objects in the pic from very close to infinity. Thats what I did to get an acceptable copy.

thinking into the future:
Pentax has two new wideangle zooms with new coating, probably image stabilization etc on the roadmap, one was shown as a mockup already. Why invest in a 35FA with all the mentioned attributes?
Far away mybe there will be a body with a even bigger sensor, all A, FA and DFA lenses are a true 645 lenses, not cropped versions. If the 35FA is alread very difficult to handle with a cropped sensor, what will be with a bigger sensor?

I hope this explains my opinion and helps everybody who has to make a similar decision

The best discussion of 645 FA lenses can be found here:

Comprehensive Testing: Results & Observations with Pentax 645 Lenses used on the 645D - The GetDPI Photography Forums

I own 5 lenses and this guy is always spot on!

By the way, I jumped from Canon to Pentax 645D two years ago, I never regretted it. The 645D is the best body I every used regarding HANDLING, not only IQ.

[jonojono]

Hi there,
I try to explain this a bit.

Assumption: main focus is landscape photography

Lets start with non IQ differences

weight: the 35a (470g) is leighter than the 35FA (560g), not much but you feel it
size: the 35a is quite a bit smaller in size than the 35 FA
diameter: 35a 77mm 35FA 82mm. 82 is a bit unusual and it adds to the cost, a 82 highend polarizer with grey filters and so on will cost you 300-400 EUR, it is vey likely that you already have 77mm equipment

now the real important things

focusing: 35FA is AF, switched off manual focusing is not bad, the focus ring has nearly no play (quite good to be honest), but it moves very easily without feeling any resistance. It happens very often, that defocussing can happen just by chance, now the field curvature starts to play a major role. A slight movement away from the optimal focussing will have drastic impacts. The 35A is much much more tolerant. The focus ring is beautifully dampened, it has a natural resistance and the depth of field engarvings are much more accurate. Basically what I mean: focussing is much easier and much quicker. If you are used to high end focussing rings (Zeiss, Leica) you will like the 35A.

IQ related things:

Field curvature: I personally think that if you focus at infinity or "normal" hyperfocal distances the field curvature is hardly acceptable and very difficult to manage. You must know exactly where to focus using a certain aperture. At closer distance it is not as strong or not visible

Smaller apertures: this point goes to the 35FA. The 35A is very good up to 14, still good at 16 but deteriorates very quickly from 16 onwards. The 35FA is better at 16 and keeps a better quality from there on

Wide open: difficult to say, I do landscape and do not have to use the lenses wide open often. What I think is as following: the 35FA is a bit better wide open, but you cannot use this adavantage due to the field curvature

Sample variation: the 35FA shows a very high variation in quality, if you buy it, buy it at a good dealer! Take shots focussed at infinity, close to infinity, mid range and so on, always with objects in the pic from very close to infinity. Thats what I did to get an acceptable copy.

thinking into the future:
Pentax has two new wideangle zooms with new coating, probably image stabilization etc on the roadmap, one was shown as a mockup already. Why invest in a 35FA with all the mentioned attributes?
Far away mybe there will be a body with a even bigger sensor, all A, FA and DFA lenses are a true 645 lenses, not cropped versions. If the 35FA is alread very difficult to handle with a cropped sensor, what will be with a bigger sensor?

I hope this explains my opinion and helps everybody who has to make a similar decision

The best discussion of 645 FA lenses can be found here:

Comprehensive Testing: Results & Observations with Pentax 645 Lenses used on the 645D - The GetDPI Photography Forums

I own 5 lenses and this guy is always spot on!

By the way, I jumped from Canon to Pentax 645D two years ago, I never regretted it. The 645D is the best body I every used regarding HANDLING, not only IQ.

Thanks for long extensive reply mazwick.

Regarding the 35FA, field curvature seems to be the biggest concern. if that is the case, i might go for the 25 F4 or the 35A version. I might have to try the 35A to ensure I have a pristine and good copy. Anyways, gives me a good reason to test Pentax focus peaking on the 645z

You mentioned new lenses on the road map? Do you have a photo of sorts or a link for me to read up on as well?

Once again, many thanks mate.

[desertscape]

Mazwick--- What you are describing as field curvature on the 35FA sounds more like spherical aberration, especially when there is a difference in what you are seeing through the lens at close distance versus long distance. Macro lenses are corrected for spherical at close distances, while all others are corrected for near infinity distances. Since this lens seems to do better at close distance, it appears to be corrected for close distances with regard to spherical aberration. Not a good thing.

[mazwick]

Thanks for long extensive reply mazwick.

Regarding the 35FA, field curvature seems to be the biggest concern. if that is the case, i might go for the 25 F4 or the 35A version. I might have to try the 35A to ensure I have a pristine and good copy. Anyways, gives me a good reason to test Pentax focus peaking on the 645z

You mentioned new lenses on the road map? Do you have a photo of sorts or a link for me to read up on as well?

Once again, many thanks mate.

You mentioned new lenses on the road map? Do you have a photo of sorts or a link for me to read up on as well?

roadmap

13 Pentax 645 medium format FA lenses coming to the US | Photo Rumors

wideangle zoom showcased, no release or announcement date given, as usual you never know when it will happen

New Pentax 645D medium format camera: pictures and some rumors | Photo Rumors

Martin

[672]

I had tried both FA and A when the D was new and kept the A due it being a little bit wider than the FA and also, in my testing, the FA was more prone to catch flares that the A suppressed.