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01-21-2009, 08:13 PM   #1
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Out-resolving, fact or fiction?

I have heard of the theory of out-resolving, meaning the K20 captures so much data that it actually out-resolves older pentax lenses. Is this true?

I am asking because if it is true then if you are using non-DA[*] lenses then the k10 is just as good?

I am using a k20 with a 30 year old SMC 500mm f4.5; am I wasting the MP of the K20? Should I use the K10 instead and save the k20 for DA[*] lenses only?

thanks

01-21-2009, 08:17 PM   #2
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QuoteOriginally posted by rdrum76 Quote
I have heard of the theory of out-resolving, meaning the K20 captures so much data that it actually out-resolves older pentax lenses. Is this true?

I am asking because if it is true then if you are using non-DA[*] lenses then the k10 is just as good?

I am using a k20 with a 30 year old SMC 500mm f4.5; am I wasting the MP of the K20? Should I use the K10 instead and save the k20 for DA[*] lenses only?

thanks
Do the shots you take look good to you? Do you love your K20D? If you answered yes to both then use the K20D and enjoy it. If not then send the camera to me and I'll use my custom built lenses on it.
01-21-2009, 08:23 PM   #3
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This ultimately depends on the quality of the optics in the lens itself, which is going to vary from lens to lens. SMC Takumar lenses are more capable than some of the modern lenses offered today, so to really know for sure, you'd have to do a side-by-side comparison.

The price of new 500mm glass could prove to be prohibitive, and you may not find that much difference between it and the Takumar. There is a reason why Canon users, who have access to L-glass, buy adapters or modify their cameras to fit Takumar lenses. My personal opinion is that 14 megapixels won't out-resolve your lens. because the finest grain films available at the time of the release of you Takumar could capture upwards of 20 megapixels of information, properly exposed of course.

The only way to know for sure is rent a DA* 300 or some FA glass and compare it to a SMC Tak 300/4 or similar.

EDIT: On a side note, I completely agree with the first response by Graphic. The amount of time spent pixel-peeping for an answer is directly proportionate to the amount of time NOT spent out there taking pictures and bettering your skills. You have to ask yourself what you want out of your pictures. Don't forget that even the best lenses used by some DSLR users have their images edited in Photoshop for contrast, sharpness, etc. It's best not to look at your shots when you get home and compare them to professional pictures you bought and hung on your wall. You never know how the professional got there in the first place.
01-21-2009, 09:35 PM   #4
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QuoteOriginally posted by rdrum76 Quote
I have heard of the theory of out-resolving, meaning the K20 captures so much data that it actually out-resolves older pentax lenses. Is this true?

I am asking because if it is true then if you are using non-DA[*] lenses then the k10 is just as good?

I am using a k20 with a 30 year old SMC 500mm f4.5; am I wasting the MP of the K20? Should I use the K10 instead and save the k20 for DA[*] lenses only?

thanks
It's not that easy. Some lenses are excellent, others are only very good, and from my experience, the differences are marginal (but noticeable) at best. For example, my A15/3.5 does seem to do better on the K10 than the K20.
It's more of a trivia thing than anything else.

01-21-2009, 09:40 PM   #5
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K20 resolution cannot do harm

QuoteOriginally posted by rdrum76 Quote
I have heard of the theory of out-resolving, meaning the K20 captures so much data that it actually out-resolves older pentax lenses. Is this true?

I am asking because if it is true then if you are using non-DA[*] lenses then the k10 is just as good?

I am using a k20 with a 30 year old SMC 500mm f4.5; am I wasting the MP of the K20? Should I use the K10 instead and save the k20 for DA[*] lenses only?

thanks
The final resolution of an image is determined by the weakest link in the lens/sensor/display chain. It is possible for a sensor to resolve better than the lens, but the sensor doesn't make the image worse.

If one is going to use only poor lenses, then maybe one shouldn't bother to buy a K20, but from a resolution standpoint the K20 should produce at least as good an image as the K10.

I couldn't find any MTF data for the SMC 500mm 1:4.5 to compare its resolution to that possible with the K20.
01-21-2009, 09:45 PM   #6
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QuoteOriginally posted by rdrum76 Quote
I have heard of the theory of out-resolving, meaning the K20 captures so much data that it actually out-resolves older pentax lenses. Is this true?

I am asking because if it is true then if you are using non-DA[*] lenses then the k10 is just as good?

I am using a k20 with a 30 year old SMC 500mm f4.5; am I wasting the MP of the K20? Should I use the K10 instead and save the k20 for DA[*] lenses only?

thanks
You have received some excellent advice so far in the thread. If the outresolving issue still bothers you, I would be happy to take your K20D and Takumar. I will send you my *ist DS and a fine Vivitar 500mm mirror lens. You won't worry about wasting MP needlessly anymore. It is the environmentally sensitive thing to do.
01-21-2009, 10:31 PM   #7
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you have a light focusing medium

and you have a light recording medium

both are finite and can be measured in dimensions

so yes, one could outresolve the other, there is no "myth", it is pure fact.
01-21-2009, 10:39 PM   #8
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do you like physics? read this
Do Sensors “Outresolve” Lenses?

i couldn't make it past the first paragraph

01-22-2009, 12:37 AM   #9
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I love how it is so irresistible to say I would love to take the gear off your hands because you not appreciating it enough to deserve it speech

However after the few thousand times it gets old. It has become cliche.

My question was how to best utilize the gear that I have. I not pixel-peeping either, rather asking for advice for how to best combo lenses with the best body.

I will practice for myself and post my results. I have seen unbelievable IQ from the DA* 300mm; that is what made me ask whether the k20 would best serve the new DA* lenses rather than older glass.

Thanks for the helpful advice. Best regards

P.s. My monitor might be the weakest link in the chain.
01-22-2009, 01:15 AM   #10
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Another weak spot is the focussing as such.
Only if the lens is really optimally focussed, you will get the optimal resolution.
But normally you focuss just once, sometimes even with AF, and get the image.
This will not give you the optimal focus, normally.
You need focus bracketing with very small steps, to get it perfect.

In my experience with lens testing, so far, all my Pentax lenses outperform the sensor, at least in the center, if focussed optimally.
01-22-2009, 01:34 AM   #11
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For me this is also a very interesting matter as most of my lenses are old manual focus ones and I am curious how would they perform on a higher mexapixel count sensor.
This concern came to me about an year ago when K20D came up some people in dpreview were saying how all these old manual focus lenses will not give a good image quality since the sensor will outresolve the lens. Of course there are some old lenses which offer better MTF characteristics than some modern glass, but anyhow I haven't seen yet a single case where a lens which was good on a K10D is bad on a K20D.
01-22-2009, 06:11 AM   #12
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QuoteOriginally posted by newarts Quote
The final resolution of an image is determined by the weakest link in the lens/sensor/display chain.
That generally tends to be me.

QuoteQuote:
It is possible for a sensor to resolve better than the lens, but the sensor doesn't make the image worse.
Those of us who underperform our equipment have the luxury of finding this sort of worry entirely moot. The day the gear can't keep up with my performance (instead of the other way around), I'll start worrying about it.
01-22-2009, 11:46 AM   #13
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Does the K20D's sensor out resolve a 40+ year old Super Takumar? I don't know and does it really matter? Cameras and lenses make pictures and that's all that matters.

Pentax K20D, 300mm f/4 Super Takumar, 1/1250 @ f/8, ISO 250.


100% crop.
01-22-2009, 03:11 PM   #14
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QuoteOriginally posted by wtlwdwgn Quote
Does the K20D's sensor out resolve a 40+ year old Super Takumar? I don't know and does it really matter?
For you and some others it might not matter, and that's ok. But this thread is for those of us who are intrested .

QuoteOriginally posted by wtlwdwgn Quote
Cameras and lenses make pictures and that's all that matters.
Methaphorically speaking it's like saying food and drinks fills the stomach, and that's all that matters.


QuoteOriginally posted by wtlwdwgn Quote
Pentax K20D, 300mm f/4 Super Takumar, 1/1250 @ f/8, ISO 250.
100% crop.

The crop seems not too bad for f/8 on an old Pentax lens.


Cheers.

Last edited by Voe; 01-22-2009 at 04:59 PM.
01-22-2009, 03:17 PM   #15
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Is the duck having a bad hair day or what.
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