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02-06-2012, 08:15 AM   #1
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DA*300mm flexibility?

How flexible can the DA*300 be? How about going beyond its inherent macroish abilities with the addition of extension tubes? Assuming that the user is completely comfortable with manual focusing at telephoto lengths, what about forgetting the SDM issue with an added TC which is no longer produced, then presumably any TC can be employed. If this is indeed the case then what, in your opinion would be the best optically? including 3rd party.

Is there a way to overcome the SDM issue when using a TC in order to engage screw-drive? Perhaps by disabling certain contacts?


Peter

02-06-2012, 08:41 AM   #2
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The lens does not have a screw drive. There was some discussion on older TCs that allowed SDM focusing. The Pentax roadmap shows a new TC, but that can take some time. The TC would make the 300 mm a really long lens - manual focus only. Check out older disucssions on quality issues.
For clsoe up work, you may use K-mount tubes, but not AF either.
While the TC trouble in Pentax land may be solved within the next 1-2 years (gulp), the extentions tube/bellows solution is still missing.
02-06-2012, 09:30 AM   #3
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If we see a successful Pentax-Ricoh Marketing strategy over the next couple of years, we may very well see the company or a third party manufacture an autofocus SDM compatible extension tube setup.
02-06-2012, 10:19 AM   #4
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I successfully used the DA* 300/4 with the Pentax AF 1.7X teleconverter with both K10D and K-5. You have to manually make a "coarse" adjustment of the focus with the lens, then half-press the shutter button and the screwdrive AF system will move an element in the teleconverter to achieve fine adjustment of the AF. This works quickly and image quality is still very good.

I don't know about the current availability of the Pentax AF 1.7X TC, but if you can grab one, it is very good.

02-06-2012, 11:01 AM   #5
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QuoteOriginally posted by Spooked Quote
How flexible can the DA*300 be? How about going beyond its inherent macroish abilities with the addition of extension tubes? Assuming that the user is completely comfortable with manual focusing at telephoto lengths, what about forgetting the SDM issue with an added TC which is no longer produced, then presumably any TC can be employed. If this is indeed the case then what, in your opinion would be the best optically? including 3rd party.

Is there a way to overcome the SDM issue when using a TC in order to engage screw-drive? Perhaps by disabling certain contacts?

Peter
I'll answer your last question first; there isn't a way to intentionally force the DA*300 (or any other DA* lens) to use the screw drive instead of the internal SDM motor.

As the previous poster mentioned, the Pentax 1.7x AF-A is (IMO) the best option for a TC for the DA*300. The Tamron 1.4x Pz-AF works decently; optically it's good but the AF is just so-so. The 1.7x AF-A will require you to manually focus the lens into the right range, but the AF itself is quick fast.

Finally, while you could use tubes on the DA*300, because of the focal length, it requires a lot of tubes to get any significant amount of increase in magnification. Just as an experiment I used all the tubes I had (at the time) and attached them to my DA*300. It worked fine, but as you can see by the picture below, it's not a very practical setup

02-06-2012, 12:15 PM   #6
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I use the k-5 and the da*300 and the combination is just fantastic! I also have the 1,7 afa, and although people seem to like that combo I honestly don't like it much. With tc the image quality is very notably degraded, and also your viewfinder goes darker. In my limited experience with the TC, I find that just cropping images from the da*300 produces better and easier results. Maybe my technique is poor with the tc, I don't know.. A few looks great, but I find it to be highly inconsistent. As to the macro capabilities of the lens; well it's a telephoto lens not a macro But also here I find that just cropping (the lens is very sharp) makes for good close ups.

I added an example. Please bare in mind that this is just the first example I found on my drive, and it is a snapshot also. It should give you a pointer to how crops looks though.

First image is full frame shot (un-cropped) :


Second is a 1:1 crop of the bee:


Looking at it now I'm not even sure the bee is entirely in focus hehe, but I think you get my point that this lens can be cropped heavily with pretty good results.
02-06-2012, 03:27 PM   #7
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QuoteOriginally posted by zapp Quote
The lens does not have a screw drive.
The lens does have a screw drive. The problem is that it's only usable by older DSLRs (K100, K110, K10 - pre v1.3, *ist models). Couldn't Pentax just make a firmware mod to disable SDM focusing if desired?
02-06-2012, 03:32 PM   #8
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QuoteOriginally posted by G_Money Quote
The lens does have a screw drive. The problem is that it's only usable by older DSLRs (K100, K110, K10 - pre v1.3, *ist models). Couldn't Pentax just make a firmware mod to disable SDM focusing if desired?
Ad G_Money said, this lens absolutely has a screw drive. In addition to the list of older DSLR bodies, I've also used it on my PZ-1p film body and it auto focus just fine using the screw drive.

It would be nice if there was a firmware mode to disable SDM focusing. If nothing else, it would serve as a good backup if the SDM motor ever failed... not that that ever happens with DA* lenses

02-07-2012, 12:31 PM   #9
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As has been said .. the Tamron PZ x1.4 and Pentax AFA x1.7 are the TCs to buy. I many use the DA*300 with the x1.7 but again as has been stated above, often it's just easier and more convenient to crop. That said however I don't think a crop to an equivalent 510mm is as good as the 300+1.7. The AFA is very easy to use, just MF focus to the approx area of your subject and let the AFA AF focus on the subject - it's very quick.

Lovely shot from Skog above. here's another of the *300 in 'macro' mode :-

02-07-2012, 12:38 PM   #10
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How do you guys get around the fact that there is no aperture ring on the lens?
02-07-2012, 12:54 PM   #11
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QuoteOriginally posted by cali92rs Quote
How do you guys get around the fact that there is no aperture ring on the lens?
The 1.4x TC and 1.7x AF-A both have aperture contacts such that you can control the aperture from the body.

In the case of tubes, you would also need tubes that have contacts to allow you to control the aperture. In the example I showed above, all 6 tubes had contacts which allowed me to control the aperture from the body (one set of AT-23 tubes and three 2x TCs with the glass removed).
02-24-2012, 09:54 PM   #12
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Did anyone try Raynox with this lens?
02-24-2012, 10:11 PM   #13
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QuoteOriginally posted by olenl Quote
Did anyone try Raynox with this lens?
I believe they won't fit without a step-down ring. The Raynox 150/250 fit between 52mm and 67mm (though I have also squeezed the 250 onto 49mm too) whereas the filter size for the *300 is 77mm.
02-25-2012, 12:59 AM   #14
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QuoteOriginally posted by Spooked Quote
How flexible can the DA*300 be? How about going beyond its inherent macroish abilities with the addition of extension tubes? Assuming that the user is completely comfortable with manual focusing at telephoto lengths, what about forgetting the SDM issue with an added TC which is no longer produced, then presumably any TC can be employed. If this is indeed the case then what, in your opinion would be the best optically? including 3rd party.

Is there a way to overcome the SDM issue when using a TC in order to engage screw-drive? Perhaps by disabling certain contacts?

Peter
DA*300 using normal close focus

With 31mm extension tube... oh and the SIgma 140 Ring Flash has the correct step up ring to fit.

"Normal" use

With 1.7AF Teleconverter


With extension tubes I've shorted out the Data contact so the camera works the lens as an unknown A-type lens.

Obviously with the AF TC the quick shift focus gets you close and the TC can handle the fine focus. Checking LR I find that about 30% of all my images have been with the 300! Oh well off to the shops to get the DA15 to go with it

Last edited by Col; 02-25-2012 at 01:05 AM.
02-25-2012, 02:18 AM   #15
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Col - that 'crying' swan and the magnificent 'pheasant' (what is it ?) are great shots !

I've just put up this thread which illustrates the close focusing ability of the DA*300 https://www.pentaxforums.com/forums/post-your-photos/176694-macro-dragonflies...and-china.html. I was supposed to be shooting birds (300+AFA x1.7) but as it was a poor day these were a satisfying substitute
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