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01-25-2014, 03:00 PM   #31
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So if we get an FF and sigma 18-35mm f1,8, will using this converter we will get 25,2-49mm f2,52 ?

01-25-2014, 03:12 PM - 1 Like   #32
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And all DA lenses will cover FF, Mmmm
01-25-2014, 03:20 PM - 2 Likes   #33
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QuoteOriginally posted by Mistral75 Quote
Indeed, this converter which will mostly be used with DA* lenses is labelled DA AW and not DA*.
The DA* name is actually pretty stupid:
1. * often activates functions in search engines and programs and can therefore be troublesome to write/search for.
2. Many people don't even know immediately how to write that symbol on a computer.
3. Writing the symbol often involves many more steps than a regular letter.
4. It's pretty minimized and therefore hard to see in ads and similar. For example Canons big L is much more visual.
5. * is most often used as a pointer in writing and can lead people to think it means that there is some kind of explanation of the DA somewhere on the page.
6. Using AW with the All-Weather explanation actually tells the potential buyer that the ens is weather sealed, DA* leaves them guessing.
QuoteOriginally posted by starbase218 Quote
I don't like this - will Pentax no longer have a pro-line of lenses?
They will for sure, but maybe under a better name.
01-25-2014, 03:49 PM   #34
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Great news, I hope they don't price it to high.

01-25-2014, 04:36 PM   #35
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First of all, this is a good thing but I can`t help but wonder how the DA*300 will perform with this TC? The DA* 300 isn`t exactly a speeddeamon to begin with.
01-25-2014, 04:46 PM   #36
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QuoteOriginally posted by TenZ.NL Quote
First of all, this is a good thing but I can`t help but wonder how the DA*300 will perform with this TC? The DA* 300 isn`t exactly a speeddeamon to begin with.
I was thinking the same and wonder how it will be on screwdrive lenses, but it might be pretty quick on 70-200mm 2.8 Sigma?
01-25-2014, 05:05 PM   #37
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QuoteOriginally posted by TenZ.NL Quote
First of all, this is a good thing but I can`t help but wonder how the DA*300 will perform with this TC? The DA* 300 isn`t exactly a speeddeamon to begin with.
Speed would not be any worse than the common Canon 400/5.6 and DA300 performs nicelly even on a Q so guess there's enough resolution to take from.
01-25-2014, 05:10 PM   #38
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QuoteOriginally posted by starbase218 Quote
I don't like this - will Pentax no longer have a pro-line of lenses?
Me thinks that , based on updates seen so far to DA limiteds, that Ricoh will come out with the "new and improved" DA* as their Pro line of lenses. As well as the obigatory red ring and HD coating I'm hoping for DC focus drive.
Hmm just imagine -Weather sealed fast focusing glass with great IQ. Gotta be a winner!

01-25-2014, 06:35 PM   #39
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QuoteOriginally posted by ak_kiwi Quote
Me thinks that , based on updates seen so far to DA limiteds, that Ricoh will come out with the "new and improved" DA* as their Pro line of lenses. As well as the obigatory red ring and HD coating I'm hoping for DC focus drive.
Hmm just imagine -Weather sealed fast focusing glass with great IQ. Gotta be a winner!
no way they will do actual update to the lens. They will just add HD coating and put a HD there and jack up the price even more.
01-25-2014, 10:01 PM   #40
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This TC & the Tamron 150-600 will make me very happy!! Hope Tamron is listening
01-25-2014, 10:16 PM   #41
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QuoteOriginally posted by Adam Quote
FYI, it turns out the source was here, not DPR, so I've updated your post. Just want to make sure the right person is credited. May be worthwhile getting that member to post in this thread.
Adam, thanks for fixing the post. I wasn't sure where the image was originally from, but I thought it deserved its own thread.

Can someone explain what happens when you put this between a (hypothetical) FF body and a DA crop lens like the DA21? My understanding is that you get almost the same FOV as the DA21 would produce on APS-C, you lose a stop of light, but the apparent depth of field is similar in the final image. Am I right?
01-25-2014, 10:43 PM   #42
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QuoteOriginally posted by Supernaut Quote
I also like asahi mans comment in the dpr tread:


Wouldn't it be great if the converter had a o-ring on the lens mount surface? It would make all old lenses semi-WR.
They should make one with O ring on both sides for old lens and O ring on camera side for the all ready wr lens . Does this one have o-ring .It would be stupid if Pentax doesn't put a ring on this one because if you put one on your camera aren't you 90 percent of the time out side trying to capture wildlife .
01-25-2014, 10:54 PM   #43
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QuoteOriginally posted by JPT Quote
My understanding is that you get almost the same FOV as the DA21 would produce on APS-C, you lose a stop of light, but the apparent depth of field is similar in the final image.
You do not really lose a stop as the equivalent f-stop on an FF camera is higher compared to that on an APS-C camera.

If the teleconverter's magnification were exactly that of the APS-C crop factor (~ 1.5x) then it would be an APS-C -> FF converter. All your lenses would continue to work on an FF camera as they did on an APS-C camera. If the optical quality of the TC were perfect you would not be able to distinguish between an image taken on an APS-C camera and (using the same lens with the 1.5x TC) and one taken on the FF camera.

A 1.4x TC is almost that ideal APS-C -> FF converter.
01-25-2014, 10:57 PM   #44
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QuoteOriginally posted by JPT Quote
Adam, thanks for fixing the post. I wasn't sure where the image was originally from, but I thought it deserved its own thread.

Can someone explain what happens when you put this between a (hypothetical) FF body and a DA crop lens like the DA21? My understanding is that you get almost the same FOV as the DA21 would produce on APS-C, you lose a stop of light, but the apparent depth of field is similar in the final image. Am I right?
In a perfect theoretical world, if you put a 1.55x teleconverter on a APS-C lens, the results would be the same on FF as they would be on a 1.55x APS-C body.

It works. Kinda. A lot of teleconverters 'interfere' with wide angle lenses - the teleconverter puts optical elements where there's elements in the lens, so they don't physically fit together.

The optics in a teleconverter are usually designed with more telecentric behaviour in mind so putting them in a wide angle lens doesn't always work the best, either.

You are kind-a correct - the DOF will be the same. I don't know what you mean by 'losing a stop of light'. You'll have exactly the same amount of light hitting the sensor, it's just spread over a broader, 'shallower' buckets rather than a narrower, 'deeper' buckets. You'll get the same results in theory.

If you're looking for this + FF to use your old lenses... I'd guess it won't work out as well as you hope.
01-25-2014, 11:16 PM   #45
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$999.99 for this.
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