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07-14-2012, 10:01 PM   #31
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QuoteOriginally posted by Class A Quote
I see you have a K-5. It would be great if you could use the variety of light sources you have access to, in order to create a situation in which the K-5 displays its infamous front-focus issue.

It would then be most instructive to see what the K-30 does in the same scenario.

Note that for low-light Tungsten AF test, it could be useful to not only use the fastest lenses you have. One of the K-5's issues was that the AF compensation based on the colour temperature of the light source dropped out too soon. The slower the lens, wide open, the quicker the drop out occurred.

So if you have difficulty to provoke the K-5 low-light AF issue, try to use low-light Tungsten light and a slower lens. The DOF will be deeper than with a fast lens but one should still be able to observe a focus shift on an AF chart, in particular with some post-processing, e.g., over sharpening to provoke halos in the sharpest areas.
This is interesting, and thanks for all the background info. I've never observed tungsten FF from any of my lenses on my K-5, but it's true that I don't often shoot my slowest lenses (DA 21 and DA 15) in those conditions. I'll give it a whirl and see if I can provoke anything.

07-14-2012, 10:13 PM   #32
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QuoteOriginally posted by deadwolfbones Quote
I've never observed tungsten FF from any of my lenses on my K-5
Good to hear that I am not alone.

Will be an interesting test nonetheless.
07-14-2012, 10:39 PM   #33
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QuoteOriginally posted by deadwolfbones Quote
I'll give it a whirl and see if I can provoke anything.
Thanks in advance!
07-15-2012, 09:49 PM   #34
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Hi deadwolfbones
I'd like to see how it handles birds in flight, if possible.

I'd also like to see a trial of it with the DA55-300, which can be pretty frustrating to auto-focus on my K-7. (oops, missed, rack through back and forward twice, give up, manual focus...) If it can make that lens auto-focus quickly, then it's a winner in my book.

Also, maybe a test with a fast lens, like the FA50, which has the dubious distinction of being give me usable hand held exposures in insufficient light for the camera to lock focus - so that's another lens that defaults to manual focus on my K-7.

My K-7 doesn't have the tungsten light auto-focus problem, but the K10d certainly does - it's a major hassle to the extent that I would not use it indoors.

Thanks


Last edited by calsan; 07-15-2012 at 09:55 PM.
07-15-2012, 10:10 PM   #35
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QuoteOriginally posted by calsan Quote
Hi deadwolfbones
I'd like to see how it handles birds in flight, if possible.

I'd also like to see a trial of it with the DA55-300, which can be pretty frustrating to auto-focus on my K-7. (oops, missed, rack through back and forward twice, give up, manual focus...) If it can make that lens auto-focus quickly, then it's a winner in my book.

Also, maybe a test with a fast lens, like the FA50, which has the dubious distinction of being give me usable hand held exposures in insufficient light for the camera to lock focus - so that's another lens that defaults to manual focus on my K-7.

My K-7 doesn't have the tungsten light auto-focus problem, but the K10d certainly does - it's a major hassle to the extent that I would not use it indoors.

Thanks
Thanks for the suggestions!

Unfortunately I don't own a 55-300 anymore, nor do I own the FA 50. My fastest (autofocus) lenses at the moment are the FA 31 and 77 at f/1.8. We've been testing extensively with those and the FA 43.

I do own an A50/1.2, and I've been messing around with manually focusing fast lenses (with and without peaking). The results thus far are good.

I'll try to do a BIF test tomorrow if I have the time, but I tried to wrap all the testing up today so that I can get the writing finished tomorrow to meet the (projected) Tuesday pub date.
07-16-2012, 05:34 PM   #36
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Ta!
Looking forward to it. Hoping that it's a good camera as I'd like to get a decent camera for my wife's birthday.
07-16-2012, 09:02 PM   #37
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QuoteOriginally posted by calsan Quote
I'd like to get a decent camera for my wife's birthday.
Very cool! Wish I could get myself stuff on my wife's B-day
07-16-2012, 10:48 PM   #38
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Thanks again, guys. I just finished up the final proofing on the review and with any luck it should be up sometime tomorrow (Tuesday). We truly appreciate your suggestions and ideas in this thread, and we hope to incorporate more community feedback into future reviews.

However, this will likely be the last review I write for Pentaxforums, as I'm pleased to say I just accepted a full-time position writing reviews for reviewed.com / digitalcamerainfo.com. Pretty much a dream job, so as you can imagine I'm very excited.

07-16-2012, 11:48 PM   #39
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Congratulations on the new position... well done

Sad loss for us here ... but we can now catch you over digitalcamerainfo.com if you happen to review Pentax gear

Good luck for the future

Cheers

Neil
07-17-2012, 12:04 AM   #40
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If you can try capturing photos of moving cars (faster is better) from an angle, with a long f2.8 lens, if possible

If it were only possible I would've lent you my Metz 58 AF-2 for HSS tests too but I'm from way across the Pacific....
07-17-2012, 09:38 AM   #41
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Deadwolfbones - congratulations on the new job! Thanks for the great work on the K-30 review.
07-17-2012, 09:39 AM   #42
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congrats deadwolfbones! Your review style is awesome. Keep it up!
07-17-2012, 09:50 AM   #43
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Thanks very much, all.
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