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01-18-2009, 11:50 AM   #16
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Hello,
I am also looking going down this route with the same lenses and I can get, in the UK, a new D10 body for the same price as the k-m. Would the d10 be the better route, I am suspecting it will be.
Thanks
Jim

01-18-2009, 12:06 PM   #17
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QuoteOriginally posted by wlank Quote
Showoff!!!
He has driven up the price of fungi infested Taks!
01-18-2009, 12:09 PM   #18
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QuoteOriginally posted by hutchys Quote
Hello,
I am also looking going down this route with the same lenses and I can get, in the UK, a new D10 body for the same price as the k-m. Would the d10 be the better route, I am suspecting it will be.
Thanks
Jim
I would go with the K10d since the K-m lacks the red-focus target indicator.
01-18-2009, 12:16 PM   #19
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Modulation Transfer Function (MTF) - The MTF describes how much a piece of optical equipment blurs the image of an object. The standard test is to see how well alternating white and black stripes show up (that is, their contrast, the difference between the whitest white and the blackest black) in the image, depending on how finely spaced they are. The MTF is a measure of how much bright-to-dark contrast is lost, as a function of the width of the stripes, as the light goes through the system. So it might be 0.95 for broad stripes, which are not significantly blurred, and 0.10 for ones almost too narrow to be viewed by the system. When reviewing the plots of the MTF, it should be noted that the human eye can resolve .05 to .10 (i.e. 5% to 10% Modulation).

If you really want to understand MTF go here.
http://www.luminous-landscape.com/tutorials/understanding-series/understanding-mtf.shtml


Last edited by Fl_Gulfer; 01-18-2009 at 12:24 PM.
01-18-2009, 12:23 PM   #20
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interesting, no one picked my favourite for manual focus/ manual apature lenses , the *istD!


Why, TTL flash, and better metering than either the K10D or K20D.

I am thinking of converting my *istD to a MF only body
01-18-2009, 12:34 PM   #21
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QuoteOriginally posted by Lowell Goudge Quote
interesting, no one picked my favourite for manual focus/ manual apature lenses , the *istD!


Why, TTL flash, and better metering than either the K10D or K20D.

I am thinking of converting my *istD to a MF only body
I almost picked it for digital macro and even have ttl ring flash for it (Macrolume). I ended up getting the k20d for an incredible price. In fact, I have the Macrolume out today looking at my options with it. Get the module for the SuperProgram or one for the *IstD and get a *istD. . . or just sell it . . .
01-18-2009, 12:43 PM   #22
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I am with Jay - K100 super

I saw a new one pretty cheap at a ritz recently...

I love the old taks and russian lenses on my k100d. I dont really have an issue with over or under exposure, because I tend to adjust my exposures hot or cold based on what I want to see anyway.

If money is no object, then the K20d with the fancier penta prism OVF is nice but I did not really have any MF issues with the K100d.


The Ist ds would also be a very good option, but the IS of the K100d is helpful IMO. (As Lowell said, the ttl flash would be nice)
01-18-2009, 03:09 PM   #23
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QuoteOriginally posted by greenboy Quote
Pardon my lack of knowledge but what does MTF mean? I was also wondering if having a higher resolution camera would be helpful or hinder pictures when using the older legacy lenses.
I'm sorry for the jargon. MTF is a measure of resolution (Modulation Transfer Function). Anyhow, big MTF means high resolution.

While it never hurts to have a high resolution camera, it doesn't do a lot of good to have a camera that dramatically out-resolves the lens.

That's because the overall resolution of the system is pretty much determined by the weakest link in the chain.

I'd like to see some comparison photos using a K20D vs K100D with a typical Takumar lens. It looks to me as if the K20D (limiting resolution of around 100 lpm) is overkill for lenses like the SMC 135/2.5 (55 lpm @ f/2.5, 78 @ f/11) while the K100D's limit of about 64 lpm might be underkill.

http://www.takinami.com/yoshihiko/photo/lens_test/pentax_tele.html

Dave

lpm = "line pairs per mm" which I'm very sloppily comparing to the sensor's pixel pairs per mm.


Last edited by newarts; 01-18-2009 at 03:15 PM.
01-18-2009, 04:34 PM   #24
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So many bodies to choose from!

Just to recap to help me make a better decision:

There is a red target indictor on the K100D but not the K2000? What about the K10D, K20D, and *ist D/DS? I'm also a bit confused about what a red target indictor is suppose to do. Since the old lenses don't have any auto-focusing capabilities, does the red target indictor mean that it comes on if the subject area it is pointing to is in focus?

Also, is metering most accurate on the *ist D/DS? But I guess the tradeoff would the loss of in-shake reduction capabilities right?

Some people also mentioned the pentaprizm viewfinder on the *ist D/DS, K10D, and K20D. But this is not available on the K100D and K2000 right? Does having the pentaprizm mean that I can see better through the viewfinder, thus allowing me to focus better?

Thanks for all the help!
01-18-2009, 04:41 PM   #25
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QuoteOriginally posted by awo425 Quote
Every Pentax body will work just fine in Av and M modes with m42 lenses. But only older istD and istDS (IMHO) will meter accurately with Pentax TTL or PTTL (in TTL mode) flash systems with M42 lenses. This cameras have dedicated TTL sensor. They also have brighter pentaprizm viewfinder. Same viewfinder was later used on K10D and K20D cameras.
istD cameras are somewhat slow and hard to find now, I would look for a low milage istDS and fit it with Katz eye split prizm focusing screen.
I was always under the assumption ttl flash wouldn't work with m42 or m lenses??? Bob
01-18-2009, 04:59 PM   #26
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QuoteOriginally posted by robert Quote
I was always under the assumption ttl flash wouldn't work with m42 or m lenses??? Bob
the *istD and DS are the only two cameras with TTL metering, which reads light off the film (or the UV filter in front of the sensor).

Because it is reading directly off the sensor or film, (or sensor) it is the only one that will work with manual lenses, because it does not need to know the apature, since it is measuring directly the light that is passing through the lens when it is stopped down.

P-TTL used in later cameras needs to know the maximum apature to meter from the pre-flash when wide open, and then control the apature so it can set it correctly as commanded by the body to insure the calculated flash is correct;
01-18-2009, 05:13 PM   #27
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QuoteOriginally posted by greenboy Quote
. . .

There is a red target indictor on the K100D but not the K2000? What about the K10D, K20D, and *ist D/DS? I'm also a bit confused about what a red target indictor is suppose to do. Since the old lenses don't have any auto-focusing capabilities, does the red target indictor mean that it comes on if the subject area it is pointing to is in focus?

Also, is metering most accurate on the *ist D/DS? But I guess the tradeoff would the loss of in-shake reduction capabilities right?

. . .
The target indicator helps focus the lens on a specific spot. With out it, you could be focused on something near the spot of choice. It doesn't indicate focus. It is kind of like a laser pointer. There is a green octagon that lights up at the bottom of the VF when the spot is focused. I wouldn't let the shake reduction be my top spec when narrowing my list. I had to pick between the target indicator or shake reduction, I would choose the target indicator for manual focus lenses.
01-18-2009, 05:18 PM   #28
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QuoteOriginally posted by Blue Quote
The target indicator helps focus the lens on a specific spot. With out it, you could be focused on something near the spot of choice. It doesn't indicate focus. It is kind of like a laser pointer. There is a green octagon that lights up at the bottom of the VF when the spot is focused. I wouldn't let the shake reduction be my top spec when narrowing my list. I had to pick between the target indicator or shake reduction, I would choose the target indicator for manual focus lenses.
Thank you. Your explanation was quite helpful. The K2000/k-m does not have the red target indicator and the K100D does. Can anyone please verify for me what other bodies has the red target indicator? i.e. the *ist D, *ist DS, K10D, and K20D? I think those are my main contenders right now. Thanks again!
01-18-2009, 05:20 PM   #29
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QuoteOriginally posted by greenboy Quote
There is a red target indictor on the K100D but not the K2000? What about the K10D, K20D, and *ist D/DS? I'm also a bit confused about what a red target indictor is suppose to do. Since the old lenses don't have any auto-focusing capabilities, does the red target indictor mean that it comes on if the subject area it is pointing to is in focus?
Yes, the target things are illuminated in red when they achieve focus. My K200D includes this feature and I really like it. I have a Super Tak 28/3.5 and an SMC Tak 50/1.4 that I shoot and get good results. The AF rangefinders in our cameras require a decent amount of light to function accurately so I typically first focus these lenses with the aperture open and then select the aperture setting if choosing, say, F5.6 or smaller.

Many users recommend the Pentax M42 to K adaptor and I agree. I've encountered problems with the cheap universal adaptor I started with.
01-18-2009, 05:37 PM   #30
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QuoteOriginally posted by greenboy Quote
Thank you. Your explanation was quite helpful. The K2000/k-m does not have the red target indicator and the K100D does. Can anyone please verify for me what other bodies has the red target indicator? i.e. the *ist D, *ist DS, K10D, and K20D? I think those are my main contenders right now. Thanks again!
the *ist D has focus indicator to tell you which AF spot is in focus, BUT it does not work on M42 lenses because the lenses do not short out the lens mount pins.

it works fine on Kmounts though
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