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03-17-2018, 02:35 PM - 2 Likes   #76
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Just been to the Photography Show 2018 at the NEC, Birmingham, UK. Nice to get the chance to handle the K1ii and DFA* 50. The Pentax/Ricoh guy was saying they had been briefed about 1.4x and 2.0x TCs on the road map... ...and probably before any new limiteds. Shame that road-map was not on display!!! ;-)


Last edited by phoebus; 03-17-2018 at 02:36 PM. Reason: spelling
03-18-2018, 09:45 AM - 1 Like   #77
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QuoteOriginally posted by rvannatta Quote
I was sort of tauht in the old school---to keep your TC's away from zooms on the theory that the zooming had already pushed the optics to the limits
Generally true but I have found the HD 1.4x RC works fine with the DA*60-250 and the DFA 150-450.
03-18-2018, 10:45 AM   #78
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QuoteOriginally posted by rvannatta Quote
I was sort of tauht in the old school---to keep your TC's away from zooms on the theory that the zooming had already pushed the optics to the limits but I have a really nice FA 300 f 2.8 and an FA 600 that would
appreciate the FA feature added I have the older manual ones.
That was probably true until at least the 80's. Any star quality tele zoom will do fine with a TC. I remember seeing a pop photo article mid 80s and 3 of the top 10 rated lenses at that time were zooms.

I've had as many issues with older primes as with older zooms. The CA and purple fringing of those older lenses can be magnified to un-acceptable standards, but mainly on consumer glass. The F -70-210, A-400, come to mind.

Last edited by normhead; 05-11-2018 at 06:46 AM.
05-10-2018, 01:59 PM   #79
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There have been unconfirmed rumors about two FF TCs on DPReview. If this will come true (photokina could be the next possible date), some might think about new FF tele lens designs to use them

Besides, i only trust official sources and real leaked images - no screenshots.So until there's nowthing to proof, the only offical statement from Pentax is that they will bring a TC.

05-10-2018, 04:32 PM   #80
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QuoteOriginally posted by angerdan Quote
There have been unconfirmed rumors about two FF TCs on DPReview.
The DFA 150-450 + DFA 1.4x TC would scratch a lot of itches.

Last edited by Paul the Sunman; 05-10-2018 at 04:39 PM.
05-11-2018, 12:24 AM   #81
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QuoteOriginally posted by Paul the Sunman Quote
The DFA 150-450 + DFA 1.4x TC would scratch a lot of itches.
Yes it would.......but

A TC does affect image quality. So the K-1 (ii) with TC and 150-450 mm becomes 210-630mm/f6.3-f7.8 at reduced image quality. Put it on a K-3ii and it is comparable longer at 230-690mm/f4.5-f5.6 with comparable depth of field. And no penalty on image quality for that sensor (or replacement camera for that).

So I have no idea wich wins. My guess is that the combo with the K-1 (ii) is better, but if that is worth the investment......I don't know.
05-11-2018, 02:34 AM   #82
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TCs are missing completely for FF in PEentax land, agrreed.
Lenses to go with TC - I mean lenses designed for TCs - are missing as well. Putting a 2x FF TC behind a 60-250 is not really a dream come true. With D-FA 150-450 you lose a lot of light even with 1.4x TC. Pentax pumped out a couple zooms with FF camera. Zooms do not match that well with TCs in the first place. DA* 200/300 could do with an AF update before you add TCs. D-FA* 70-200 would benefit from TC 1.4/2 probably, but how many D-FA* zooms were sold to go with the TC? New lenses should come first. A 1.4x TC could be useful and replace the DA 1.4x TC.
Besides that, the roadmap is full of delayed lenses. Lensewise we have not seen a lot of innovation recently from Pentax. Electronic aperture, constant changes to AF motors, ... nothing really fast, no bright primes, no diffractive optics, nothing really special - just gap fillers. Don't get me wrong - gaps are filled and the roadmap shows some nice ideas, still I don't understand the hype about a couple TCs and other ideas. Pentax does well fitting gaps with limited ressources.
05-11-2018, 03:15 AM   #83
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QuoteOriginally posted by zapp Quote
TCs are missing completely for FF in PEentax land, agrreed.
Lenses to go with TC - I mean lenses designed for TCs - are missing as well. Putting a 2x FF TC behind a 60-250 is not really a dream come true. With D-FA 150-450 you lose a lot of light even with 1.4x TC. Pentax pumped out a couple zooms with FF camera. Zooms do not match that well with TCs in the first place. DA* 200/300 could do with an AF update before you add TCs. D-FA* 70-200 would benefit from TC 1.4/2 probably, but how many D-FA* zooms were sold to go with the TC? New lenses should come first. A 1.4x TC could be useful and replace the DA 1.4x TC.
Besides that, the roadmap is full of delayed lenses. Lensewise we have not seen a lot of innovation recently from Pentax. Electronic aperture, constant changes to AF motors, ... nothing really fast, no bright primes, no diffractive optics, nothing really special - just gap fillers. Don't get me wrong - gaps are filled and the roadmap shows some nice ideas, still I don't understand the hype about a couple TCs and other ideas. Pentax does well fitting gaps with limited ressources.
The hype is in fact extremely easy to get: if they, distantly, plan for TCs, it means there will be lenses to use them with.

Simple isn't it ?

05-11-2018, 05:19 AM   #84
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Pentax has 6 (six) TCs in the catalog... why you need more?

http://www.ricoh-imaging.co.jp/japan/support/catalog/pdf/lenses_accessories.pdf (p. 20)
05-11-2018, 06:16 AM   #85
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QuoteOriginally posted by Andrea K Quote
Pentax has 6 (six) TCs in the catalog... why you need more?

http://www.ricoh-imaging.co.jp/japan/support/catalog/pdf/lenses_accessories.pdf (p. 20)
along with extension tubes unchanged since 1975?!
05-11-2018, 06:49 AM   #86
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QuoteOriginally posted by Andrea K Quote
Pentax has 6 (six) TCs in the catalog... why you need more?

http://www.ricoh-imaging.co.jp/japan/support/catalog/pdf/lenses_accessories.pdf (p. 20)
Because no matter what it is, you always need more.

Right now with my 1.4 causing vignetting on my K-1, it's looking like a waste of money. I'll have to buy one that does APS_c and FF to replace it. And the 1.7 makes purple fringing a lot worse. A 2x quality 2x that would take my Tamron 300 2.8 to 600 ƒ5.6 is long overdue. That lens was designed to be used with a TC. Unfortunately the TC it was designed to be used with, they only made about 10 of them. Trying to find one second hand is next to impossible.
05-11-2018, 06:59 AM   #87
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It's not about needing more, it's about having at least one good product. Fortunately Ricoh Imaging recognized this need (now let's see how long it takes...)

The only AF-enabled FF converter is the 1.7x Adapter - which is doing the focusing itself. Does it work with KAF4 lenses?
05-11-2018, 07:10 AM - 1 Like   #88
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QuoteOriginally posted by RonHendriks1966 Quote
Yes it would.......but

A TC does affect image quality. So the K-1 (ii) with TC and 150-450 mm becomes 210-630mm/f6.3-f7.8 at reduced image quality. Put it on a K-3ii and it is comparable longer at 230-690mm/f4.5-f5.6 with comparable depth of field. And no penalty on image quality for that sensor (or replacement camera for that).

So I have no idea wich wins. My guess is that the combo with the K-1 (ii) is better, but if that is worth the investment......I don't know.
The TC does not reduce image quality on the subject, only over the whole frame. It may infact increase the lw/ph devoted tot eh subject of the photo by 37%. Pentax says the overall loss of quality is about 3% on the hD DA 1.4. The odds of you ever taking a picture where that loss of quality is noticeable is pretty small.

By itself, the statement a TC reduces image quality only refers to over the whole unreduced frame. It doesn't refer to the subject of the photo in my bird images. IN those the TC vastly increases IQ.

Not using a TC just spreads limited lw/ph over a much wider area. If you get 3000 lw/ph in a sensor without the TC, you get 2910 with the TC crammed into 1/3 less field of view. You can lose more resolution stopping down from ƒ5.6 to ƒ8 on some lenses and most of us do that without thinking.

If you have 2000 line pairs on your subject without the TC you could have as much as 2740 on your subject with it. That's a heck of bump.

The Blue Jay knows I'm right.

Last edited by normhead; 05-11-2018 at 07:19 AM.
05-11-2018, 08:01 AM   #89
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QuoteOriginally posted by normhead Quote
Because no matter what it is, you always need more.

Right now with my 1.4 causing vignetting on my K-1, it's looking like a waste of money. I'll have to buy one that does APS_c and FF to replace it. And the 1.7 makes purple fringing a lot worse. A 2x quality 2x that would take my Tamron 300 2.8 to 600 ƒ5.6 is long overdue. That lens was designed to be used with a TC. Unfortunately the TC it was designed to be used with, they only made about 10 of them. Trying to find one second hand is next to impossible.
Manual focus? If yes sell the Tamron and buy the A* or FA* 645 300mm F4 + RC 645 2x + 645>K adapter. I obtain a 600 F8, then underexpose 1 stop to have the same shutter times as at F5,6. On k-1 the image qualty of this combo is astonish.

Warning big files:

FA* 645 300mm @F4



FA* 645 300mm + RC 645 2x @F4



FA* 645 300mm + RC 645 2x @F5,6 (I invite you to downlad the image and count the bricks on the red building or the leaves of the trees)

Last edited by Andrea K; 05-11-2018 at 08:18 AM.
05-11-2018, 08:12 AM - 1 Like   #90
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QuoteOriginally posted by Andrea K Quote
Manual focus? If yes sell the Tamron and buy the A* or FA* 645 300mm F4 + RC 645 2x + 645>K adapter. I obtain a 600 F8, then underexpose 1 stop to have the same shutter times as at F5,6. On k-1 the image qualty of this combo is astonish.

Warning big files:

FA* 645 300mm @F4



FA* 300mm + RC 645 2x @F4



FA* 300mm + RC 645 2x @F5,6
That's impressive, but I still want a TC that tells the SR what FL is on the camera, passes on all exif info. and maintains auto-focus and auto aperture I've seen enough time messing around with odd combos to believe I have the patience and perseverance to make the most of an adapter that doesn't do those things.

My theory about tedious work is, avoid it at all costs. I know I won't take notes. I want the camera to be able to do it. More fastidious people than myself might find this an acceptable solution.
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