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03-11-2013, 08:40 PM   #16
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Thanks.

Check out 'The Reach of the Q' thread for other samples folks have contributed using long lenses, and see the reviews of various lenses on the Adapted lenses sticky at the top of the Q forum.

03-11-2013, 08:52 PM   #17
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QuoteOriginally posted by crewl1 Quote
This was shot at 1/60. Probably on the lowest end of the speed scale for a hyper hummingbird.
You could probably shoot a still GBH at lower if you needed it at dusk or dawn.
Thing is, with the Q I want to keep ISO at base for best results, so I am stuck with that and the optimum aperture on DA*300 of 5.6.
Shutter speed is all I have to play with for exposure.


Agree.
Lens would needs to be f4-f8 to get max results.
ISO needs to be 125. Anything above ISO400 for the Q would be worse than DSLR + crop IMO.
that said, with a 50mm (275mm eq) on the Q.
anything lower than 1/100 is very low.

In real life, most of the time we put 300mm+ lenses so image how low we have for the shutter.
03-12-2013, 12:27 PM   #18
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>> the Pentax adapter is simply more durable and built to lower tolerances.

higher tolerances
03-12-2013, 12:49 PM   #19
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QuoteOriginally posted by MalcS Quote
>> the Pentax adapter is simply more durable and built to lower tolerances.

higher tolerances
Lower tolerances, higher precision (higher tolerance = less precision)


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03-12-2013, 02:05 PM   #20
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QuoteOriginally posted by Adam Quote
Lower tolerances, higher precision (higher tolerance = less precision)
Technically, I am sure you are correct, but common usage would seem to be (more often than not) higher tolerances = higher precision, lower tolerance = lower precision rather than low deviation or high deviation from spec.

Less ambiguous would be 'loose' tolerances and 'tight' or 'close' tolerances I guess.
03-12-2013, 08:39 PM   #21
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OK, I'll nitpick, those of us in Engineering don't use lower or higher when referring to tolerances but we will use the term loose and tight to describe a tolerances when verbally comparing components, but on specifications or drawings it will be a plus or minus numeric value. Regardless I just ordered a Pentax OEM adapter and hope it's built to the correct tolerances.

Hans
03-13-2013, 05:07 AM   #22
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I studied and worked in Mechanical Engineering in Canada. In college and in the field, the term "high tolerance" means that tolerances are very closely machined. I can see that this is ambiguous, but that is how the term is used here. I also did some work with Americans in Wisconsin and Michigan, and I'm sure they use the term in the same way; high tolerance = tight tolerances and high cost.
03-13-2013, 06:35 AM   #23
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Not saying Wikipedia is the Be-all End-all, but HERE is their explanation of Engineering Tolerance.

You might be surprised at how ambiguous the definition is. Also. don't confuse allowance with tolerance.

A number is assigned to manufacturing tolerances. Generally, a high manufacturing tolerance number means a wide variation in "fit" is permissible. A low manufcaturing tolerance number means only a small variation in "fit" is permissible.


Last edited by monochrome; 03-13-2013 at 06:45 AM.
03-13-2013, 08:18 AM   #24
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QuoteOriginally posted by crewl1 Quote
This was shot at 1/60. Probably on the lowest end of the speed scale for a hyper hummingbird.
You could probably shoot a still GBH at lower if you needed it at dusk or dawn.
Thing is, with the Q I want to keep ISO at base for best results, so I am stuck with that and the optimum aperture on DA*300 of 5.6.
Shutter speed is all I have to play with for exposure.


Beautiful shot Larry

Hans
03-13-2013, 10:50 AM   #25
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QuoteOriginally posted by audiobomber Quote
How about Q with DA*300 vs K-01 with DA*300 and a good quality TC, cropped?
Not exactly the comparison you asked for, but you might be interested in my comparison of the Q + DA*300 vs. K-5 + 2x + 1.4x + DA*300:

I've been meaning to do more comparisons but haven't had a good opportunity.

Adam, thanks for writing the review. I'm taken aback by the many vituperative comments posted on the review page, e.g. one commenter going off on your claim of "pro image quality", a claim you never actually made (unless you edited the article in response to that comment). It might help to include some more of the many outstanding shots that have been posted here in the Q forum. In fact, maybe I'll post some such links in a comment.
03-13-2013, 10:53 AM   #26
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QuoteOriginally posted by baro-nite Quote
I'm taken aback by the many vituperative comments posted on the review page
Heaven forfend someone should make a positive comment about a Pentax mirrorless camera.
03-13-2013, 12:34 PM   #27
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Not sure to ask here or start a new thread, but I have a question about the genuine K-mount to Q adapter - does it work with M42-adapters?

I have a cheap ebay K-mount to Q adapter today, works reasonably well but has no aperture control, neither would the M42-PK adapter attach (it just fel out of place). I have several M42 S-M-C Takumars that would be nice to use with the genuine adapter.
03-13-2013, 02:42 PM   #28
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QuoteOriginally posted by DonThomaso Quote
Not sure to ask here or start a new thread, but I have a question about the genuine K-mount to Q adapter - does it work with M42-adapters?
Hi DonTomaso,

It will work, but as you guessed without any control of the aperture via the adapter's aperture ring since M42 lenses don't have the same aperture control mechanism as full K mount lenses have. Pentax M42s are actually a nice match for the Q since they are usually pretty compact and have well damped long throw focus rings that give you a fine level of control over focusing. Despite the perception that such a small sensor will have virtually infinite DOF, focusing accuracy with adapted lenses on the Q is very critical for good images.

Scott
04-06-2013, 08:39 PM   #29
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Hi,

I asked this in the "Use the K-mount adapter for Pentax-q" comments section, but I thought I'd post here as well, for possibly better response numbers, hope that's OK.

Is there a difference as to which aperture control one uses, the lens or the adapter? Is one better than the other?(maybe due to closeness to the sensor?)

And I guess I should have asked first, why is there a need for an aperture in the adapter in the first place, especially if the lens already has it's own aperture ring? Is it just mostly for lenses without an aperture ring?

Thanks!
04-06-2013, 08:53 PM   #30
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The aperture control in the adapter moves the one in the lens so there is no difference.

If the lens has an aperture dial you should use it for more accuracy.

Aperture control in the adapter lets you use DA lenses that don't have their own aperture ring.
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