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01-09-2008, 02:48 PM   #1
SouthShoreRob
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How do I get the most out of my 1.7x teleconverter?

Would someone, with tangible experience, please direct me in how to get the most out of my new teleconverter? Preliminary test shots on my part aren't looking too promising. Specifically, what should I do with...

a) the metering selector
b) the focus point selector
c) the M, AF-C, AF-S selector

Plus, if you have any other advice / input, it would surely be appreciated. If it matters, I plan on using this converter mostly with my FA*200mm when birding.

Thanks,

Rob

01-09-2008, 03:20 PM   #2
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What parts aren't looking promising? Gaining and locking focus? The end result?

I assume you're using the FA*200/2.8 - that should be plenty of light to acquire focus during daylight hours.

I use mine in all the same way that I use my other lenses, mostly center-weight metered and AF-S when I want to auto-focus. I don't think it does as well focusing as the lens without the TC, although that should be expected since the TC eats up light. Then again, I think most wildlife photographers complain about Pentax's abilities in the auto-focus super-telephoto range.
01-09-2008, 04:20 PM   #3
SouthShoreRob
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thanks for the quick reply

QuoteOriginally posted by carpents Quote
What parts aren't looking promising? Gaining and locking focus? The end result?

I assume you're using the FA*200/2.8 - that should be plenty of light to acquire focus during daylight hours.

I use mine in all the same way that I use my other lenses, mostly center-weight metered and AF-S when I want to auto-focus. I don't think it does as well focusing as the lens without the TC, although that should be expected since the TC eats up light. Then again, I think most wildlife photographers complain about Pentax's abilities in the auto-focus super-telephoto range.
Yes, the FA* 200mm F2.8. Light and compatibility are not the issues. It's my lack of know-how. What I mean is...I pre-focus close to what looks good to my eye, then half-press the shutter to have the AF kick in, and then click. Yet, in spite of what looks good (sharp) in the viewfinder, the end result is less than sharp ie. slightly out of focus.

So far, I have been using AV mode, green metering, green focus, and AF-S. Here's a sample test photo taken this afternoon. Straight from the camera, but cropped.

Last edited by SouthShoreRob; 02-09-2009 at 02:50 PM.
01-09-2008, 05:44 PM   #4
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I bought mine in 1991 when I got a PZ-1 and wanted autofocus on my long (ish) zoom a vivitar Series 1 70-200 F3.5. Although the documentation says it only works on F2.8 and faster lenses, I tested it out before I bought it and it worked just fine on the F3.5 vivitar.

Since then, I found a really good condition SMC 300 F4, and again it works very well with this lens, in all but the most extreme low light conditions.

When I got my *istD, I began using this combination (300 F4 and 1.7x AF TC) as an effective 500mm F6.7 lens.

below I have posted a shot taken with this combo, using a flash at 1/150th I think you will agree it is quite sharp.

In the same post you will see a shot taken with my K10D, at 1/30 and a 70-200 F2.8 zoom plus 1.4x TC for comparison.
Scroll down until you get to my posting

https://www.pentaxforums.com/forums/general-pentax-photography/13308-do-you-a...tly-blurr.html

I find the lens with the AF TC works best with long fast lenses at much less than infinity focus. The chickadee for example was shot from about 25 feet.

I find that the cameras all tend to focus short using the TC on distant objects, although this may be a function of hand holding, as a little vertical shake can move the focus point up or down a lot, and with nature shots, (things on the ground) downward motion also means possibly setting the focus on the ground in front of your image.

01-09-2008, 06:50 PM   #5
SouthShoreRob
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well taken

QuoteOriginally posted by Lowell Goudge Quote

I find that the cameras all tend to focus short using the TC on distant objects, although this may be a function of hand holding, as a little vertical shake can move the focus point up or down a lot, and with nature shots, (things on the ground) downward motion also means possibly setting the focus on the ground in front of your image.
Thanks for chiming in. Your points are well taken. I viewed your photos and noted what you described for each sample. Personally, I think up and until I have more experience/practice with this new teleconverter, that I may just have to manually focus (it won't be for hockey anyhow) and only reap the benefit of the magnification.

Aside from that, I would suppose that pumping up the ISO to enable greater shutter speeds - thus reducing the chance of shaking - would also be advisable. 200mm x 1.7 is 340mm effective focal length; shooting at 1/350th probably just isn't good enough.

Rob
01-09-2008, 07:56 PM   #6
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I meant to ask what camera you have?

Film or DSLR and if DSLR is an *istD or DS or is it DL or K10/K100 .

This is important, not so much for anything you do with the 200mm, but if you use older lenses, because you can't use P-TTL flash with older lenses.

That is why I shoot the 300mm+1.7x on my *istD, even though I also have a K10D. I really like the ability with a good flash shot to stop the lens down for depth of field, and the best possible sharpness from the lens, and also because with flash, I can usually isolate wildlife from the background, because the background, which is further away, it naturally under exposes and fades to black. This eliminates annoying distractions. Flash also allows you to keep the ISO low


Also with digital, you need to consider with your combination shoting at 1/500 because the "crop factor" of digital sensors effectively causes you to amplify the impact of camera shake.

A couple of additional points, with manual focus, the AF TC also might give you trouble, because it may not be focused to allow you to go to infinity focus on the lens itself. the AF is reasonably good, so don't worry, have a go at it, just think carefully where you are pointed when shooting distant objects.


Good luck and please post some of your results.
01-09-2008, 08:49 PM   #7
SouthShoreRob
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QuoteOriginally posted by Lowell Goudge Quote
I meant to ask what camera you have?

Film or DSLR and if DSLR is an *istD or DS or is it DL or K10/K100 .

This is important, not so much for anything you do with the 200mm, but if you use older lenses, because you can't use P-TTL flash with older lenses.

That is why I shoot the 300mm+1.7x on my *istD, even though I also have a K10D. I really like the ability with a good flash shot to stop the lens down for depth of field, and the best possible sharpness from the lens, and also because with flash, I can usually isolate wildlife from the background, because the background, which is further away, it naturally under exposes and fades to black. This eliminates annoying distractions. Flash also allows you to keep the ISO low


Also with digital, you need to consider with your combination shoting at 1/500 because the "crop factor" of digital sensors effectively causes you to amplify the impact of camera shake.

A couple of additional points, with manual focus, the AF TC also might give you trouble, because it may not be focused to allow you to go to infinity focus on the lens itself. the AF is reasonably good, so don't worry, have a go at it, just think carefully where you are pointed when shooting distant objects.


Good luck and please post some of your results.
I'm shooting my K10D. I respect what you're saying about using your flash, however, this is not something I'm too interested in at this point. Indeed I should also consider the crop factor as these multipliers add up quickly. Certainly, once I have some clue how to make this teleconverter work for me, I'll be happy to share my findings.

Rob
01-09-2008, 10:43 PM   #8
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QuoteOriginally posted by SouthShoreRob Quote
I'm shooting my K10D. I respect what you're saying about using your flash, however, this is not something I'm too interested in at this point. Indeed I should also consider the crop factor as these multipliers add up quickly. Certainly, once I have some clue how to make this teleconverter work for me, I'll be happy to share my findings.

Rob
Also consider the following:

1) Switch to manual focus if you have to. That will guarantee that what you want in focus will be in focus.

2) The FA200 doesn't have a tripod mount. When you add the 1.7x TC (or any TC) you are going to have a lot of lens wobble. The movements may be very slightly but that's all it will take to make your pictures soft.

Are you using your MLU + 2 second self timer? Or a cable switch? For medium to slower shutter speeds you need to minimize:

a) camera and lens shake from pressing the shutter release and
b) mirror slap, which can also cause image degradation, especially with telephoto lenses.

Using the timer or cable release will let the camera & lens wobble settle down. The MLU will eliminate mirror slap.

3) Get a good tripod & good ball or pan/tilt head if you don't have one already. A proper tripod/head will really let the FA200's capabilities shine; this will be especially important when you attach a TC to the lens since it will provide a lot of stability. I'm a tripod addict and have a number of them. But my most used 'pod is a lightweight 4 section carbon fiber tripod with a Markins M10 ballhead. My cameras all have L brackets.

01-10-2008, 01:24 AM   #9
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Besides what's mentioned, try to use it once a week. Over time, you will get a hang of it.

I set it to continuous focus some time just to practice in the streets or park. Playing around this teleconverter in combination of various primes..

I had just used it today again in a tennis tournament and you can have a look the shots here

Colonial Classic: Saffin VS Roddick
01-10-2008, 03:09 PM   #10
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I'm left scratching my head with why you're seeing those results... these were all shot with the Voigtländer 125mm & Pentax 1.7x AF TC shortly after getting the 125:
https://www.pentaxforums.com/forums/post-your-photos/14153-last-dogwood-leaves.html

...and from photo IMGP7871 thru IMGP7879 in this gallery:
Best of Nala album | m8o | Fotki.com

I hope you'll agree a successful marriage...

During that session, I pointed down to my left wrist and took some handheld shots of my watch, being the macro range, 212mm focal length adding the TC. I'll have to convert and post them; quite sharp.
01-10-2008, 06:16 PM   #11
SouthShoreRob
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QuoteOriginally posted by m8o Quote
I'm left scratching my head with why you're seeing those results...
Me too - hence this post. I will, undoubtedly learn from trial and error. Not a lot of time to practice these days unfortunately as winter has greyed out most every sky of late. Surely time will tell, but at this moment, I do believe my results are less than stellar given the low iso and corresponding shutter speeds. Next sunny day, I'll definitely give it another go!
01-10-2008, 07:01 PM   #12
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Ya, keep at it for sure.

Here's what I was saying about the handheld shot pointing down @ my wrist. I got the MF lens 'close' to focus @ the 2-ish ft distance, then the 1.7x AF TC did the rest.
Attached Images
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PENTAX K10D  Photo 
01-10-2008, 07:10 PM   #13
SouthShoreRob
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WOWZERS now that's sharp. What was the initial lens?
01-10-2008, 07:15 PM   #14
m8o
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The Voigtländer 125mm f/2.5 APO-Lanthar Macro used during the same session when I took the leaf and dog shots.
01-10-2008, 08:14 PM   #15
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QuoteOriginally posted by m8o Quote
The Voigtländer 125mm f/2.5 APO-Lanthar Macro used during the same session when I took the leaf and dog shots.
Some very nice reasults...
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