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09-10-2009, 03:50 AM   #16
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I have quite good and extremely cheap 28-90mm Quantaray.
Use it for macro work constantly (1:2).
Other my favourite lenses are all manual, like very good Vivitar 28-200mm.
I disassembled some my manual lenses and they are much better made then current consumer zooms. Tamron 70-300mm and Sigma 70-300mm are expecially cheap inside.

09-10-2009, 04:06 AM   #17
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QuoteOriginally posted by Marc Sabatella Quote
There are 300mm primes designed for film (eg, the K300/4, the M*300/4) and also 300mm primes designed for digital (DA*300/4). The latter is *way* out of your price range. The K300/4 can sometimes be had for around the cost of, say, the DA55-300 that is being recommended by most as the best zoom lens in this class,
Where can I find a K or M* 300mm prime for the price of a DA55-300?!

I do know however that it is possible to find mint examples of M200f4 or A200f4 - cheaper than a new telephoto consumer zoom. These would surely give the DA50-200 a run for its money in image quality and certainly come out on top in build quality and value for money.

(btw - I have seen DA* telephotos selling for less than A* and M*)

Last edited by Spock; 09-10-2009 at 04:15 AM.
09-10-2009, 10:22 AM   #18
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QuoteOriginally posted by Spock Quote
Where can I find a K or M* 300mm prime for the price of a DA55-300?!
Don't know about the M* - I'd guess being a "*", it's going to be more expensive - but the usual price for the K300/4 is in the $300-$400 range. See, for example, KEH.com.

QuoteQuote:
I do know however that it is possible to find mint examples of M200f4 or A200f4 - cheaper than a new telephoto consumer zoom. These would surely give the DA50-200 a run for its money in image quality and certainly come out on top in build quality and value for money.
I've got the M200/4. A great deal at well under $100, for sure. But IQ-wise, I wouldn't call it better than the DA50-200 - except maybe a little at f/5.6. Of course, it's a stop faster, and it works better with a TC, plus it has a much nicer focus ring. But it's also much bigger and heavier, lacks AF, and of course also the 50-199mm range :-). So overall, I wouldn't necessarily recommend it over the 50-200 unless you're sure need the extra stop, plan to use it extensively with a TC, or see yourself mostly using MF. I'm happy to have both, but the 50-200 gets way more use.

If one is considering the M200/4 just to save money, I'd recommend at least considering one of the 70-300's, too, which are actually more comparable to the M200/4 in some ways than the DA50-200 is (closer in size, closer in maximum aperture at 200mm, and usually closer in price).

Last edited by Marc Sabatella; 09-10-2009 at 10:29 AM.
09-10-2009, 01:43 PM   #19
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QuoteOriginally posted by newarts Quote
If cost is not very important, get the best lens you can, like the Pentax 55-300.

If cost is important, soft focus can be corrected using deconvolution software like FocusMagic. Deconvolution is a mathematical approach to correct focus errors; small errors can actually be corrected, not simply masked.

Using such software is easy, if a need for critically focused images with wide-open long lenses arises occasionally (of course not as easy as not using it at all).

Here's an example; Hand-held, Soligor 200mm @ 1:2.8, plus 1.5x Kenko TC, original on left, Focus Magic correction only (no "usm sharpening") on right.


Dave in Iowa
Dave I just stumbled upon Focus Magic and now I read your post, can you start another thread and post some more info and perhaps examples? That would be great! I am tempted to buy that piece of software, but I have bought too much of this kind in the past which proofed to be unuseable or poorly designed, to allow myself sinking more money and time in something I have not enough info about.

I was already searching for deconvlution software for Mac for a while and didn't know, that Focus Magic is based on that.

Ben

09-10-2009, 02:56 PM   #20
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QuoteOriginally posted by newarts Quote
If cost is not very important, get the best lens you can, like the Pentax 55-300.

If cost is important, soft focus can be corrected using deconvolution software like FocusMagic. Deconvolution is a mathematical approach to correct focus errors; small errors can actually be corrected, not simply masked.

Using such software is easy, if a need for critically focused images with wide-open long lenses arises occasionally (of course not as easy as not using it at all).

Here's an example; Hand-held, Soligor 200mm @ 1:2.8, plus 1.5x Kenko TC, original on left, Focus Magic correction only (no "usm sharpening") on right.


Dave in Iowa
Of course, I can see the noise sharpened considerably as well.
09-10-2009, 03:08 PM   #21
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QuoteOriginally posted by GLXLR Quote
Of course, I can see the noise sharpened considerably as well.
I use Focusmagic alot, works stinking great. Never thought about noise, guess it does not discriminate, if it is there, it will get processed.

Cheers. Mike.

Wait!, is there such a thing as OOF noise?, must look into this.:ugh:.
09-11-2009, 05:06 AM   #22
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QuoteOriginally posted by Ben_Edict Quote
Dave I just stumbled upon Focus Magic and now I read your post, can you start another thread and post some more info and perhaps examples? That would be great! I am tempted to buy that piece of software, but I have bought too much of this kind in the past which proofed to be unuseable or poorly designed, to allow myself sinking more money and time in something I have not enough info about.

I was already searching for deconvlution software for Mac for a while and didn't know, that Focus Magic is based on that.

Ben
Ben,

I'll take some test photos, process them, & publish the results in a new thread.

Focus Magic works well in stand-alone mode, but is easier to use as a plug-in (I use it with Paint Shop Pro); just make a selection by any means and apply focus correction. It'll also correct motion smear.

I think noise reduction should be run after deconvolution if necessary.

I think there's a free trial period & registration is only $15USD- well worth the cost

I don't know if there's a Mac version.
09-11-2009, 05:13 AM   #23
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QuoteOriginally posted by newarts Quote
I think there's a free trial period & registration is only $15USD- well worth the cost
Are you sure? I just looked and it says US$45 registration code - am I looking at the wrong thing?

09-11-2009, 07:06 AM   #24
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QuoteOriginally posted by Andrezao Quote
@yeatze you mean which Film Lenses I got? Well, for the K1000 I have a Pentax-m SMC 50mm and a Sigma 80-200mm, the MZ-10 I have a Sigma 28-80 Macro. is that for the M42 Adapter?
Since the K1000 and the MZ-10 are both K mount cameras (neither is M42, that would be on Pentax cameras older than a K1000), their lenses will work on your K20D without the need for any adapter. However, any fully manual lenses, like the Pentax M SMC 50mm, will need the aperture ring turned on in your menus as xjjohnno pointed out.

In fact, any lenses that you have that are not exclusively digital (like the DA series are) will also work on your MZ-10. And any of your lenses that has an aperture ring will work on your K1000. So any old K mount lens, like your M 50mm, can be made to work on all three cameras, and any new K mount lens that has an aperture ring and a large enough image circle, like my Tamron 28-75mm f/2.8, will work on all three cameras.

This is the beauty of buying Pentax so far, you can use all your old lenses. Even old screw mount M42 lenses will work with an adapter.

Last edited by CFWhitman; 09-11-2009 at 07:11 AM.
09-11-2009, 07:18 AM   #25
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QuoteOriginally posted by Nass Quote
Are you sure? I just looked and it says US$45 registration code - am I looking at the wrong thing?
You are right! I was remembering wrong (or from ages ago.) It is still worth the cost.
09-11-2009, 07:51 AM   #26
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QuoteOriginally posted by newarts Quote
You are right! I was remembering wrong (or from ages ago.) It is still worth the cost.
Yeah, to be honest it's a nobrainer! But first I may give this freebie a shot which also has a deconvolution engine
09-11-2009, 07:56 AM   #27
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Here's a quick example of refocusing with Focus Magic as a Plug-in. The photo was taken hand held in low light so all couldn't be in focus. Kari is shown before and after refocusing.


The refocusng is overdone perhaps, but you get the idea. The photo is imporved at least for a family album I think.

Dave

Last edited by newarts; 09-11-2009 at 08:17 AM.
09-11-2009, 08:15 AM   #28
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Amazing. How does this work?
09-11-2009, 08:15 AM   #29
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QuoteOriginally posted by Nass Quote
Yeah, to be honest it's a nobrainer! But first I may give this freebie a shot which also has a deconvolution engine
I downloaded ImageAnalyzer & it looks dandy. It appears to be a superb advanced image processing tool.

Dave
09-11-2009, 08:35 AM   #30
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QuoteOriginally posted by Spock Quote
Amazing. How does this work?
The out-of-focus image of a point is roughly a disk. In effect, deconvolution reverses the process, restoring each disk to a point.

It can do a lot to improve a poor lens' performance. This is not a fake improvement if the way the lens focuses the image of a point is known.

In principle, there is no limit to which resolution can be increased, if one knows (or can estimate) exactly how an out-of-focus point is blurred. But in practice it isn't very easy to do & requires a lot of computation.

For example, say a lens focuses a point with an intensity profile like a hill, /\, software can find the center of the hill and replace the hill's profile with a point. Perfect resolution!

It is not all that easy to do, but you get the idea.

Dave
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