[Reddaddy]

Are my two K5 Pentax lenses (18-55 and 55-300)) compatible with a K3? Are they recommended?

[Paleo Pete]

Any K mount lens that works on another Pentax camera, film or digital, should work. I use old 50mm lenses I've had for 30 years on my K30.

Whether those specific ones are recommended, I have no idea. I don't keep up.

[Kozlok]

The 18-55 will work on the K-3, but it's not a very impressive lens. The higher resolution of the K-3's sensor will show off the optical flaws of that lens. Might be a good time for a better normal lens.

[Adam]

Are my two K5 Pentax lenses (18-55 and 55-300)) compatible with a K3? Are they recommended?

Those lenses will work, but to really take advantage of the K-3's sensor, you'll want some premium zooms and/or primes. Here are a few good zooms:

Sigma 17-70mm F2.8-4 Contemporary - Introduction - Pentax Camera Forums
DA* 16-50mm vs. Sigma and Tamron 17-50mm F2.8 Comparison - Introduction - Pentax Camera Forums
Pentax-DA* 50-135mm F2.8 Review - Introduction - Pentax Camera Forums
Pentax DA* 60-250mm F4 Review - Introduction - Pentax Camera Forums
DA 12-24mm vs Sigma and Tamron 10-24mm Comparison - Introduction - Pentax Camera Forums

Adam
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[ElJamoquio]

Are my two K5 Pentax lenses (18-55 and 55-300)) compatible with a K3? Are they recommended?

They'll work. What are you trying to do?

[interested_observer]

The lenses will work just fine. Are they the absolute best - no. But no single lens will be best at everything. They will certainly help you determine what you are interested in and what focal length you seem to enjoy shooting with. You might find that you want some lens - that might be "faster", i.e., work better in lower or limited light.

It is probably better to shoot with what you have and they will lead you to what you what to do, and where to spend your funds. Remember you can only spend your money once. You can go out and spend a lot of money on a lot of lenses and wind up using on a couple. The kit lenses are a way to help you determine what and how you want to shoot.

Also, any Pentax and M42 (the old screw mount lenses) will work on any of the Pentax K camera bodies. The M42 will require a pretty simple adapter (runs about $25 to $40).

[DSims]

In terms of what's recommended, it depends on your goals. If you want to get the best Image Quality for the $ you spend, then you want a few lenses that cost almost as much as (or even more than) your camera body.

Hopefully, if you could afford a K-3 you could also afford 2 or 3 better lenses. Similar to what Adam suggested above, a classic kit for that camera would be a used DA*16-50, used DA*50-135, and a DA*300/4 (used prices can be much lower, especially on the first two). Then while you're getting great shots with those lenses you slowly consider for yourself whether you someday might need a ultra-wide lens ( e.g. DA10-17 or Sigma 8-16), or a fast prime like an FA77/1.8, DA*55/1.4, or FA*24/2.



EDIT: Sorry, now that I read your post again, I realize you don't even have the K-3 yet. So if better Image Quality is what you're after, try one or more of the above lenses on your K-5 first. This will make a bigger difference - the IQ improvement from a better lens on the K-5 will be greater than you can get by putting your old lenses on a K-3.

Once you experience the difference, you'll want to get a few more lenses for your K-5 before ever spending on a K-3. Don't worry, the K-5 can take full advantage of the quality of these lenses already.


Only get the K-3 now if it has a special feature or functionality you really need, such as the improved AF performance. And if you need high AF performance (e.g. for shooting sports) you need to carefully match the camera with the right lenses anyway. Also realize that some of the improvements the K-3 brings can also be had in the K-5 II or IIs for less (although the K-3 can still be a better overall camera for those who really need it).

---

Last edited by DSims; 06-02-2014 at 07:55 PM.

[Imageman]

Im gonna be the radical here.


Those lenses will be fine. Resolution is a blind alley, sure its useful in some images but the very best images ever taken are not the sharpest. A sharp image doesn't make a good image. If you take a razor sharp portrait of a lady she wont thank you, she wont even like the images although she might say she does to be polite. Take a softer focus image of that same lady with an inferior lens and she will sing your praises.


The k3 sensor out resolves your lenses, so what, film always out resolved the lenses and nobody ever said there was anything wrong with that. Photographers simply used the lenses they preferred, so use yours.


The high resolution of the k3 sensor simply means your actually seeing what the lens maker intended instead of a fuzzy lower resolution image of an inferior sensor.

[DSims]

Those lenses will be fine. Resolution is a blind alley, sure its useful in some images but the very best images ever taken are not the sharpest. A sharp image doesn't make a good image. If you take a razor sharp portrait of a lady she wont thank you, she wont even like the images although she might say she does to be polite. Take a softer focus image of that same lady with an inferior lens and she will sing your praises.


The k3 sensor out resolves your lenses, so what, film always out resolved the lenses and nobody ever said there was anything wrong with that. Photographers simply used the lenses they preferred, so use yours.


The high resolution of the k3 sensor simply means your actually seeing what the lens maker intended instead of a fuzzy lower resolution image of an inferior sensor.

This doesn't even make any sense. I barely know where to start. Neither of us knows whether better IQ is what Reddaddy is really after, but since we've both assumed this is his objective:


First of all, portraits of women is a special case that definitely doesn't apply to all of photography, so it can't be used as a representative example.

Secondly, film didn't always out resolve the lenses, and it's one of the reasons Medium Format and Large Format film could be (and still is) so useful.

Thirdly, the K-5 doesn't have a "fuzzy, lower resolution inferior sensor," as you imply. Even my 6MP K100D Super could take advantage of better lenses, and everything since my 10MP K200D can definitely take advantage of them.


Finally, you whole post suggests that sharpness is the only characteristic a high quality lens brings to the table, which is far from being the case.

[Imageman]

First of all I didn't imply the k5 is inferior you made that assumption.


Second we can discount whether portraits of ladies are representative that's a matter of opinion.


Thirdly it depends what film and lenses your talking about. Im talking about the highest quality film, and the highest quality lenses


Ilford FP4 resolves 110 lppmm
Agfapan APX 150 lppmm
Kodak Technical Pan 320 lppmm


The highest resolution film is therefore 320 line pairs per mm, that's phenomenal resolution


Matched only by the very best lenses


Carl Zeiss Biogon f4.5 38mm has an extraordinary resolution and can give 200 lppmm
Carl Zeiss S-Planar 5,6/120mm, 170 lppmm


Compare these figures to the usual comparisons that are made when deciding if digital outperforms film.


Fujicolor Superia 100 color negative film is around 63 lppmm.
Kodak Gold 100, is about 110 lines/mm


The Canon 28-70mm f/2.8L At 40mm, at f/8 is around 61 lppmm


Modern zooms represented by the canon 28-70 are much closer to the fujicolor and Kodak gold film stock and the k3 is higher resolution that fp4. this is where the idea that film is lower resolution than modern digital sensors comes from.


My opinion of the k3 for example is that the k3 sensor is capable of resolving 120 line pairs per mm, and when matched to a high quality zoom of around 60 to 80 line pairs per mm, the combination can out perform many older lenses and Fuji Superia film stock.


But I maintain that not only do the modern zooms fail to resolve to the level of the best old prime lenses such as the S-Planar, but the k3 fails to resolve to the level of either Agfapan or Kodak Technical Pan. and the film as I said in my earlier post resolves well beyond the highest quality lenses I have been been able to discover. This make perfect sense.


What would be the point of spending a lot of money designing and manufacturing lenses that out resolve the recording medium, that's just pointless and bad business. For that reason, the recording medium (film) would always outresolve the lens


I agree that digital lenses and sensors do outperform the run of the mill film and lenses that were available, but when you examine the very best lenses and the very best film, digital still loses. And the lenses are as I said out resolved by the film.

[DSims]

First of all I didn't imply the k5 is inferior you made that assumption.


Second we can discount whether portraits of ladies are representative that's a matter of opinion.


Thirdly it depends what film and lenses your talking about. Im talking about the highest quality film, and the highest quality lenses

1) I inferred it because you clearly implied it. You already know the OP is coming from a K-5.

2) It's not a matter of opinion - you used a poor example

3) If both film and digital sensors out-resolve lenses, then the obvious conclusion is one should get better lenses. But you suggest it's better to replace a sensor that's already out-resolving the kit lenses with another one that out-resolves them by even more!

[tim60]

The lenses will work. If you are happy with them on the current camera then you will get the same performance.


K3 body only and then use any money left over to buy a particular lens that would help you do what you want to do.


I recently got a K3 body only because I did not need another kit lens and I have enough lenses anyway. The K3 is lovely to use - I was persuaded by a few minutes tryout of a K5 that it is worth going to a top of range body. Even my lesser lenses give images my friends are impressed by.

[Imageman]

You draw conclusions that have no basis in what you read don't put words in my mouth. Im stating what I understand about sensors film and lenses.


The facts as I understand them and have stated them are.


The best Film out resolves the best lenses.


The best film out resolves the best sensors


The k3 out resolves some of the film that was used


The k3 out resolves many of the lenses available today


I spoke about the relationship between resolving power of lenses and resolving power of the recording medium as an example to support my contention that lenses are allowed to be less sharp than the recording medium they are used on and nobody should care about that.


Lets take an example of a fictitious car manufacturer. Lets assume that all the roads are made in such a way that it is impossible to drive beyond 100 mph


Lets assume that a variety of cars exist with top speeds of between 50 and 100 mph. It takes a lot of money to design and build a car that will go at 150 mph rather than 100. so it will cost 3 times as much to buy as a car that will do 100 mph. Should the manufacturer make such a car when its totally pointless as no consumer will ever be able to see this top speed or indeed any speed beyond 100. The answer is no this is manufacturing suicide and the only case for it is as a marketing exercise.


Similarly if you make lenses that cost up to 3,000 dollars and they resolve to the quality of the best sensors available, why spend a fortune creating a lens that resolves beyond the sensor and try to market it at 3 times the price. Nobody would buy it, all that extra resolution that cost so much to design and build is lost when taking an image.


It makes no sense whatsoever to produce lenses that out resolve the recording medium unless its cheap and easy to do. its easy and cheap to make lenses that resolve up to 50 lppmm, move to 100 lppmm and they become very expensive to make, move to 150 lppmm and your talking exotic design and extreme expense. zooms cannot be made affordably in this resolution. Ok you can make very exotic lenses. some I believe cost over 30,000 dollars.


Are you suggesting that as sensor advances continue, we will all have to buy 30,000 dollar lenses simply to stay ahead of sensor resolution. That's nonsense.


The OP asked if his existing lenses would work with k3 or must he buy better lenses that's all he asked and that's all I answered. I answered that question saying his lenses would be fine. The fact that the recording medium is capable of resolving better than his lenses is no reason to change those lenses whatsoever.


I have simply stated some facts about resolutions of lenses and film that confirm that in film days nobody cared that film could resolve more than lenses.


Photography is all about the lens it always has been and it always should be.


As for saying if a lens resolves below the resolving power of the recording medium you should replace the lens with one that exceeds the resolving power of the medium, that's most ill advised statement ive ever heard.


There is only one reason to replace a lens, that's if a different lens gives you better images and you can justify spending the money. whatever better means to you and what you want from your images.


I have lenses with different characteristics some resolve beyond the sensor resolution some below. I don't care that some of them resolve below the resolving power of the sensor I use, what has that got to do with anything. Its what the images look like that I care about, and its what any photographer should care about.


Im used to seeing high resolution recording medium - film and being unconcerned that it out resolves most lenses. That's the way it should be, and that is all ive ever said, and that's the advice I give once more to the OP, his lenses will be fine on k3, and he should be unconcerned about it, and if he finds a lens he prefers, then by all means buy that.

[stevebrot]

The facts as I understand them and have stated them are.

A few of your assumptions are incorrect or not fully accurate. I won't dispute line-by-line (waste of good keystrokes), but that is my opinion. That being said, I will address the OP's concerns from the perspective of my personal experience, both as a long-time and current film user and as the owner of both a K10D and a K-3. My conclusions are essentially the same as yours.

There is the concept of the medium (regardless of type) out-resolving the lens. The statement is frequently made on this site and is almost always the cause of significant discussion. Though there is some truth to the claim, it is not as simple as often stated. A given lens will often attain higher resolutions with a higher resolution medium regardless of its performance with a lower resolution medium. The tests at photozone.de provide plenty of evidence of this.

From my personal experience, a good example may be the Pentax-DA 18-55/3.5-5.6 v1 on the K-3. I have used that lens for years on my K10D with good (some would say, miraculous) results, but to be completely honest, it is not as good on that body as most of the other lenses in my bag. When mounted with the K-3 it performs better than on the K10D. I will repeat...the DA 18-55 performs better on the K-3 than the same lens on the K10D. Whether doing so is a waste of good megapixels relative to shooting with the same lens on say, the K-5 is a matter of user preference and taste, however.

What is more, I have been somewhat amazed at the performance of many of my vintage and cheap lenses when paired with the K-3. I thought I might have to retire my Zenitar 16/2.8 Fisheye. Nope, it works great; I have not been disappointed. Ditto for my early-80s vintage Tamron 70-150 zoom. Every lens I have mounted works better on the K-3 than on the K10D and (catch this) as least as good as the same lens on 35mm film.* Are any of them as good on the K-3 as say, my FA 77/1.8 Limited? I haven't done the head-to-head comparison yet, but I do know that my Helios 44M came close on the K10D and it would not surprise me if the results were similarly close with the K-3.

It may still be asserted that shooting with such pedestrian glass is laughable on a high-end camera, regardless of results. I guess a good laugh is a good thing. I like laughter.


Steve

* I am referring to scanned images from Ektar 100 film at 4000 dpi using my Nikon scanner. That resolution (normalized to same final image size) is about the same as that of the K-3 sensor. It is my opinion that Ektar 100 may easily support a higher resolution scan, say 5000-6000 dpi, but that is conjecture and I don't have the means to test.

[ElJamoquio]

The 28-70 isn't a modern lens, it's 21 years old and it resolved ~130 lp/mm on old sensors.

Modern lenses on modern sensors are resolving 225 lp/mm with color, see e.g. Sony E 10-18mm f/4 OSS (SEL-1018) - Lab Test / Review - Analysis

That's much higher than any color film resolution I'm aware of, but I don't know much about film.