[clickclick]

The LBA just never lets up. I recently picked up a Pentax-F 1.7x AF converter, and now I'm wondering how it would couple with one of the vintage 500mm lenses. I already have the D FA 150-450, and I have found that converter works pretty well with that lens, but back of my mind is that I always hear TCs work better with primes. That got me to looking around at the vintage 500mm Takumars and SMC variants. I'm thinking the two are optically the same but it's about different coatings. So, what are folk's thoughts on these lenses? Worth looking for one, or a waste of money since I already have the 150-450? Of course, the LBA is so strong, I'm not sure if I can resists anyway, but for once I'm trying to be sensible....

Thanks!

[UncleVanya]

The 500mm f/4.5 lenses that I have seen are very soft compared to today's telephoto lenses. I do not think it will come anywhere near the quality you are getting from the 150-450.

[Adam]

The LBA just never lets up. I recently picked up a Pentax-F 1.7x AF converter, and now I'm wondering how it would couple with one of the vintage 500mm lenses. I already have the D FA 150-450, and I have found that converter works pretty well with that lens, but back of my mind is that I always hear TCs work better with primes. That got me to looking around at the vintage 500mm Takumars and SMC variants. I'm thinking the two are optically the same but it's about different coatings. So, what are folk's thoughts on these lenses? Worth looking for one, or a waste of money since I already have the 150-450? Of course, the LBA is so strong, I'm not sure if I can resists anyway, but for once I'm trying to be sensible....

Thanks!

Personally I've found the 500mm's to be very sharp, but they also suffer from noticeable aberrations due to the simple optical design. At the end of the day the 150-450mm does better overall.

[vonBaloney]

Yeah, I would think that zoom is way better than that old prime, although from what I've seen the Tak is better than I thought it would be. Still, the reason that "primes are better" is because in general primes are sharper & faster. But with 50ish years of technological improvement on the Tak, I would expect the modern zoom to blow it away.

[stevebrot]

That got me to looking around at the vintage 500mm Takumars and SMC variants. I'm thinking the two are optically the same but it's about different coatings. So, what are folk's thoughts on these lenses? Worth looking for one, or a waste of money since I already have the 150-450? Of course, the LBA is so strong

All three versions of the Pentax 500/4.5 (Super-Takumar, S-M-C Takumar, and Pentax-K) share the same optical formula, so you are correct that the main difference would be coatings, build details and mount support. Whether it makes sense to buy is another matter. Consider:

• The AF with feature of your TC will not work well with that slow a lens (resulting ~f/8 aperture is too slow for PDAF).* Of course, the same is true for that TC with your D FA 150-450mm.
• All versions of the 500/4.5 are "beasts" of size and weight
• Your D FA 150-450mm likely has better optical performance

Steve

* The aperture limitation is not one of image brightness, but a matter of light angle that results in prism "black-out" of the PDAF splitter prism (full explanation (pdf) HERE).

[monochrome]

Minimum Focus Distance K500/4.5 = 1000cm
Minimum Focus Distance D FA150~450 = 200cm

[zzeitg]

I always hear TCs work better with primes

That's true, but 1.7x is not a standard TC.

I recently picked up a Pentax-F 1.7x AF converter

So did I. And after a couple of quick tests, I'm pretty sure that to nail correct focus will be "trial and error" process (with major part of errors). For sure it's far away from the 1.4x TC user experience....

[clickclick]

That's true, but 1.7x is not a standard TC.





So did I. And after a couple of quick tests, I'm pretty sure that to nail correct focus will be "trial and error" process (with major part of errors). For sure it's far away from the 1.4x TC user experience....

Not standard because of the AF aspect or something optically I'm missing?

What's your impression of this TC? I'm finding with the 150-450 that upsampling the image from 450 to match it with the 1.7x is a toss up. Sometimes the shot seems better with the TC, and sometimes it seems better with the 150-450 upsampled. The 1.7x appears to have a fair amount of CA and does introduce purple fringing though.

Part of what's hard on this decision is the LBA aspect and the enjoyment of trying different things. In the lens reviews on the forum, Kerrowdown has a really nice shot with the SMC 500.mm - pics like this make it hard to resist trying:

SMC Pentax 500mm F4.5 Reviews - K Prime Lenses - Pentax Lens Reviews & Lens Database

[monochrome]

You really need to have long lens skills, both critical focus and damping with left hand, to nail it with the 500/4.5. Plus good support. I get a lot of motion blur but that’s my fault. In good light it is contrasty enough but subject to atmospherics. The hard sights help. Getting filters into the rear mount is a chore.

All of which makes it fun to use. I have a documented 1998 purchase K mount version.

[stevebrot]

Kerrowdown has a really nice shot with the SMC 500.mm - pics like this make it hard to resist trying:

Kerrowdown can pretty much make any lens sing, just sayin'...

A full walk through both the M42 and Pentax-K reviews show several examples that are more typical as well as some sharp critiques. CA is a recurring theme (often with the comment that it is easy to correct) as is difficulty in focusing and a need to use with tripod. If I saw one for $180 USD in decent condition, I might bite, but not at $350-500.


Steve

[jatrax]

I've used both long vintage primes and the DFA 150-450. IMHO, there is no contest. If you have neither and are on a budget the primes will be fine. But if you already have the 150-450 nothing vintage you can buy will be better.

Maybe an FA*250-600 but that is in another league altogether.

[zzeitg]

Not standard because of the AF aspect or something optically I'm missing?

What's your impression of this TC? I'm finding with the 150-450 that upsampling the image from 450 to match it with the 1.7x is a toss up. Sometimes the shot seems better with the TC, and sometimes it seems better with the 150-450 upsampled. The 1.7x appears to have a fair amount of CA and does introduce purple fringing though.

Because of the AF aspect. So far the focus accuracy hasn't impressed me. Anyway I have to try the adapter with different lenses to be able to evaluate its performance. The need of manual pre-focus does not make it easier, but probably I just need some practice.


(By the way the AF adapter came to me in "Ricoh" box and seems to be brand new. I'm wondering... are these 1.7x AF adapters still officially in production?)

[monochrome]

Because of the AF aspect. So far the focus accuracy hasn't impressed me. Anyway I have to try the adapter with different lenses to be able to evaluate its performance. The need of manual pre-focus does not make it easier, but probably I just need some practice.


(By the way the AF adapter came to me in "Ricoh" box and seems to be brand new. I'm wondering... are these 1.7x AF adapters still officially in production?)

I believe RIcoh reboxed old Hoya / Pentax Gear. Some items they restickered the UPC (my AIV 77 Lim was restickered).

.:

[clickclick]

Thanks for all the replies. This is mostly what I was thinking, and it's nice to get some first hand feedback.

It sounds like if you got one at the right price, it would be fun to play with, but to use it with reasonable expectations.

Luckily, cures for LBA haven't materialized.