[Pentaxor]

I still think that a blind test would reveal very little difference between the lenses you're talking about. I would bet $5.00 that the differences would be insufficient to allow people to beat chance by a statistically significant margin. The "guess the lens" thread bears this out to some extent, though it's far from a methodical analysis.

That doesn't mean I don't understand that photographers have preferences, lenses they like, lenses they don't. I'm just saying that they're very personal and probably not visible in the final product - that is, more about how the photographer feels than how the images look.

as I mentioned in an earlier post, the FA35 is quite selective. there are situations that it would seem to render like the FA31, and situations that it doesn't. or just plainly saying that there are factors that influence a certain rendering of the lens. if we disregard or don't have images for technical and identical image comparison that would show the differences in contrast, slight sharpness, FOV, and bokeh rendering, it is a bit of a challenge determining both lenses.

[jsherman999]

as I mentioned in an earlier post, the FA35 is quite selective. there are situations that it would seem to render like the FA31, and situations that it doesn't. or just plainly saying that there are factors that influence a certain rendering of the lens. if we disregard or don't have images for technical and identical image comparison that would show the differences in contrast, slight sharpness, FOV, and bokeh rendering, it is a bit of a challenge determining both lenses.

Good points.

I think bokeh and OOF transition were the biggest differences (besides FL) between my copy of the 31 & 35. To my eye, the 31 had better bokeh in most situations, hands down. That said, I sold the 31 and kept the 35, because they were close enough in other attributes and for for what I used them for.


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[jstevewhite]

Right, I was sticking to comparing the two lenses being talked about in this thread, but if you want to keep the effective FOV the same, substitute maybe the $250 FA 50 1.7 in place of the 35. But that's a larger question that quickly gets out of scope from what I was asking. (would prefer to keep the general "FF vs aps-c" argument from breaking out )

Well, I don't think you and I have anything left to argue about there... LOL!

My question was more... Pentax's best prime (arguably) on aps-c vs. a very, very close equivalent on FF, for about the same price. You could shoot either FAs on FF, but a $1000 lens on a $2000, $2500 or $3000 body might be passing the 'affordable' threshold for a lot of folks.

Mmm... At the risk of sounding snobbish.. if you can't afford a $2000 body and a $1000 lens, maybe FF isn't your bag. I mean, I already have FF capable lenses all over, so it wouldn't be that big a hit, but if I had to start out new and had a $3k budget, I'd probably spend it on the K-5 and a couple of DA LTDs, or the K-5 and a couple of good APS-c Zooms. Maybe a used 16-45 and 50-135. Although if Pentax were to introduce a FF, I would expect their DA lens sales to drop like a stone as people bought FA - FFA? - lenses in case they wanted to upgrade later.

At some point would you be willing to sacrifice some degree of lens IQ to make an affordable combo on FF?

(If you'd rather keep the FOV the same in the consideration, substitute the excellent FA 50 1.7 for the FA 35 f/2.)
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Wow... too many variables. It would depend on whether we are talking the unmeasurable, preferential characteristics (bokeh, rendering, etc) or actual resolution and contrast - for example, the FA35 is sharper in the corners than the FA31 at all apertures, and as sharp in the center. Since I don't shoot "bokeh-critical portraits" with a ~30mm, it's a big "meh" to me.

In the end, beyond the physical viewfinder, I'd want to see a concrete advantage in the image output before I jumped ship. Honestly, I'd probably test both with the same lens, because the things I would be looking at aren't FOV related and it would tell me much more about the bodies. But if I'm buying for more than the viewfinder, the system has to have some way of showing me that it will produce better images as a system, all else being equal.

I love cameras as a class, but I'm very pragmatic about what I want to PAY for.

[GeneV]

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Here's an interesting question: which combo would folks here rather shoot:

$2000 FF K-1 Pentax + $300 FA 35 f/2

or

$1400 K-5 + $900 DA 31ltd


Both combos come out to $2300.

That might be an easy question to answer, so how about:

What price difference in that combo would be your personal threshold to keep you in aps-c?

For example:

$2300 FF K-1 = $2600 for combo ($300 more for FF)
$2500 FF K-1 = $2800 ($500 more for FF)
$3000 FF K-1 = $3300 ($1000 more for FF)
...

etc... what would be your $ cutoff? (assuming a smallish-bodied FF Pentax with updated AF, at least equiv to D700 in performance, but a bit smaller).

Jay, there are way too many ifs in that scenario to make that call with any precision. First, there is the whole FF digital v. APS-c issue which is far broader than these two lenses. I'd have to see what I do with the theoretical K1 that I can't do now.

I'd say that the FA43 Ltd. would be the more attractive general use AF option to go with the new FF body than the FA31. The attraction of the FA31 as a next purchase would be that it splits the difference between two FF WA workhorses I use on film, and does so with speed and quality. It might be attractive to take the place of both a re-released FA35 and, say, a future FA28/2.

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Last edited by GeneV; 05-22-2011 at 08:18 PM.

[selar]

It's an unusual focal length. I guess we are paying for that as well as other differences already mentioned here.

[pcarfan]

Sorry! I thought you had asked for opinions and as I had owned both in the past i voted for the FA31, but I did not check your images.

[twitch]

.

Here's an interesting question: which combo would folks here rather shoot:

$2000 FF K-1 Pentax + $300 FA 35 f/2

or

$1400 K-5 + $900 DA 31ltd


Both combos come out to $2300.
.

K-1 hands down..... and the FA31 is my favourite lens.

[Pentaxor]

Good points.

I think bokeh and OOF transition were the biggest differences (besides FL) between my copy of the 31 & 35. To my eye, the 31 had better bokeh in most situations, hands down. That said, I sold the 31 and kept the 35, because they were close enough in other attributes and for for what I used them for.


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Yes, those two attributes what defines the FA31. aside from those, it's a close call between the two Pentax lenses. I'm not sure what to make of the DA35/2.4 however, but it is quite nice to have for those who are short on the budget.

[jsherman999]

... but if I had to start out new and had a $3k budget, I'd probably spend it on the K-5 and a couple of DA LTDs, or the K-5 and a couple of good APS-c Zooms. Maybe a used 16-45 and 50-135.

That's probably a better way to ask the same thing: Say your budget was $3K, and the K-1 had been released the same time as the K-5, or maybe the year before, and was going for $2300 - would you buy the K-1 + FA 35 + $400 more glass, or the K-5 + FA 31ltd + $700 more glass?

What I'm getting at is... the age-old advice that's been handed down since the days of the Spotmatic has been to always spend your money on glass, to buy the best glass possible because the glass is what determines ultimate IQ more than anything, and a glass 'investment' will retain it's value longer.

But I'm wondering if that advice meant more in, say, 1985, than it does now, yet we still give it the same weight - when we shouldn't, perhaps.

That advice came out of the era that had companies like Two Star, Komara, JC penny, etc making a lot of lenses for every mount. Back then, the delta between bad, OK, good, and great was huge. Now, I think most if not all lenses are good enough, if not just plain good, and many are pretty great - even inexpensive ones. This discussion about the IQ difference between the 31ltd and the FA 35 highlights that.

So, with that in mind.... we're in a slightly altered universe. The K-1 exists at $2300. You have a $3K budget, give or take a smidge. Design your kit.

Mine: K-1, FA 35 f/2, FA 50 1.7, Tamron 28-75 f/2.8.

I'd shoot with that for a year and be very happy. With the following year's budget, I might add a long telephoto like the Sigma 100-300 f/4, the 77ltd, and maybe the Samyang 14mm f/2.8 MF.

(EDIT: I might swap the Samyang for the Tamron - getting the 14mm the first year, and the 28-75 the second. Yes, I think I'd do that.)

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[GeneV]

What I'm getting at is... the age-old advice that's been handed down since the days of the Spotmatic has been to always spend your money on glass, to buy the best glass possible because the glass is what determines ultimate IQ more than anything, and a glass 'investment' will retain it's value longer.

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I think the equation is a bit different in the digital age. In the film era, a more expensive body meant a bit of improvement in the exposure program, maybe interchangeable finders and screens, durability. However, the same glass and the same film will work pretty much the same way.

In the digital age, the sensor can change everything--ISO, color, noise, contrast, even FOV (going from APS-c to FF) Moreover, AF improvements can make a big difference in results.

[jstevewhite]

That's probably a better way to ask the same thing: Say your budget was $3K, and the K-1 had been released the same time as the K-5, or maybe the year before, and was going for $2300 - would you buy the K-1 + FA 35 + $400 more glass, or the K-5 + FA 31ltd + $700 more glass?

What I'm getting at is... the age-old advice that's been handed down since the days of the Spotmatic has been to always spend your money on glass, to buy the best glass possible because the glass is what determines ultimate IQ more than anything, and a glass 'investment' will retain it's value longer.

But I'm wondering if that advice meant more in, say, 1985, than it does now, yet we still give it the same weight - when we shouldn't, perhaps.

This is what I've been getting at with all the people handing out that same advice. That advice comes from an era when you could swap film and take the SAME IMAGE with the SAME LENS on two different bodies; all that was different were ergonomics, durability, and features. Now the film is built in. That, I think, changes the equation.

That said, I don't think, if I were on a budget, I would have chosen the 31 over the 35 anyway. If I'm not on a budget, I can give the money to the LTD build, but if I have budget limitations, I'm going for the performance/cost ratio of the 35.

That advice came out of the era that had companies like Two Star, Komara, JC penny, etc making a lot of lenses for every mount. Back then, the delta between bad, OK, good, and great was huge. Now, I think most if not all lenses are good enough, if not just plain good, and many are pretty great - even inexpensive ones. This discussion about the IQ difference between the 31ltd and the FA 35 highlights that.

So, with that in mind.... we're in a slightly altered universe. The K-1 exists at $2300. You have a $3K budget, give or take a smidge. Design your kit.

Mine: K-1, FA 35 f/2, FA 50 1.7, Tamron 28-75 f/2.8.

I'd shoot with that for a year and be very happy. With the following year's budget, I might add a long telephoto like the Sigma 100-300 f/4, the 77ltd, and maybe the Samyang 14mm f/2.8 MF.

(EDIT: I might swap the Samyang for the Tamron - getting the 14mm the first year, and the 28-75 the second. Yes, I think I'd do that.)

.

Dammit. You make it tough. The lenses I use most often are the macro and the long telephoto, and there's just no way to fit that into the budget you've given me - but that's true even if I go with the K-5.

Assuming that the K-1 has a similar, full-frame version of the k-5 sensor... I'm thinking

K-1; FA 35 f2; 50mm F1.7; Used M series 100 f4 macro. That'd still be a squeeze at $3000.

If the K-1 is less than 20MP, though...

K-5; 16-45; M 100 f4; Tak 300 f4 (eekbay ~$250-$300)

[selar]

Sorry! I thought you had asked for opinions and as I had owned both in the past i voted for the FA31, but I did not check your images.

No problem, the images were only for the benefit of those who hadn't owned both at some point.

[selar]

Look how close the resolution figures are:

[jstevewhite]

Look how close the resolution figures are:

I think it's interesting that they trade the lead @5.6, where they are nearly identical in MTF.

[jstevewhite]

So, with that in mind.... we're in a slightly altered universe. The K-1 exists at $2300. You have a $3K budget, give or take a smidge. Design your kit.

I was thinking about this today as I was re-organizing my bag. I've been working on my kit for 4+ years, and I STILL don't have it designed - and I've spent a metric buttload more than $3k!! LOL