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02-03-2014, 06:48 AM   #151
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QuoteOriginally posted by gazonk Quote
I have only one teleconverter, a Vivitar 2x I bought around 30 years ago, and which I still haven't taken a single useful picture with. It's simply not sharp enough. So I guess I'm suspicious.

I wonder though, is there any chance that this teleconverter would make any sense on my DA55-300 (on K-5)? Or will I be better off cropping? The sharpness of the DA55-300 isn't exactly overwhelming at 300mm, but I think the center sharpness is OK when used at fairly close range (in contrast - it always seems pretty "muddy" to me when focused at infinity).

I guess I'll know soon, since the 55-300 is a quite common lens I guess someone will test the 1.4 converter with that lens as soon as it is released.
The aperture will become slower...

02-03-2014, 07:15 AM   #152
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QuoteOriginally posted by starjedi Quote
The aperture will become slower...
Yes, I know, I'm not sure if it will even AF reliably any more at 300mm f/8.1?
02-03-2014, 08:28 AM   #153
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Probably not, but as you say, wait and see. Keep in mind that t/c's give a stop less aperture combined with less DOF... so you have to stop down even further.

If you handhold, you might be doing it a f11.
02-03-2014, 08:43 AM   #154
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QuoteOriginally posted by ElJamoquio Quote
Probably not, but as you say, wait and see. Keep in mind that t/c's give a stop less aperture combined with less DOF... so you have to stop down even further.

If you handhold, you might be doing it a f11.
Bah, one OEM, I think it was Minolta, used to sell a 600/8 AF. Yep, an AF mirror lens :O

55-300+tc Can't be worse

02-03-2014, 08:43 AM   #155
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I think it would be easier to make a 1.4x teleconverter than a 2x one. Also, a lot will depend on having decent glass in front of it. But I would think the DA * zooms (50-135/60-250) would be OK with it, understanding that they already aren't speedy at auto focus without a TC.
02-03-2014, 01:35 PM   #156
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forget using a TC with the 55-300 unless you are birding or looking at something fairly static. I tried the 55-300 combination on both the K-X and K30 for airshows and it just hunted and hunted and hunted. you lose too many fstops for airshow work with that combination. On a really bright day, maybe, it might work but you are better off going Manual focus and birding or something slow moving.

but get a nice 55-300, with good light and the right conditions and you will still get some stunning photos from that combination.
02-03-2014, 01:38 PM   #157
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QuoteOriginally posted by gazonk Quote
Yes, I know, I'm not sure if it will even AF reliably any more at 300mm f/8.1…?
I've used my 1.7 TC on my A-400 5.6, for a total of 9.3, you may as well focus by hand, when it thinks it's done focusing, you can see it's out, in the viewfinder.
02-03-2014, 01:54 PM   #158
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QuoteOriginally posted by lancer3397 Quote
forget using a TC with the 55-300 unless you are birding or looking at something fairly static. I tried the 55-300 combination on both the K-X and K30 for airshows and it just hunted and hunted and hunted. you lose too many fstops for airshow work with that combination. On a really bright day, maybe, it might work but you are better off going Manual focus and birding or something slow moving.

but get a nice 55-300, with good light and the right conditions and you will still get some stunning photos from that combination.
It can be done.

Using the 55~300 at 300mm on a K3, I successfully achieved focus lock on flying Bald Eagles at approximately 150' altitude handheld in AF.S, single center AF point. Granted, this was against a bright clear blue sky but they were really up there. 200% mag (16x) only fills half the LCD.

Testament to the new K3 AF system.


My wife later told me I kept saying, "GOT him!"

02-03-2014, 04:47 PM - 2 Likes   #159
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QuoteOriginally posted by gazonk Quote
Yes, I know, I'm not sure if it will even AF reliably any more at 300mm f/8.1?
I use the 55-300 with a cheap Vivitar Series 1 1.4x. AF is a bit slower, but it is still useable.








02-03-2014, 04:53 PM   #160
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Thanks for the examples of beautiful pictures with supposedly weak components. An inspiration.
02-03-2014, 05:33 PM   #161
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Like the first one....
02-03-2014, 10:51 PM   #162
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QuoteOriginally posted by boriscleto Quote
I use the 55-300 with a cheap Vivitar Series 1 1.4x. AF is a bit slower, but it is still useable.
Great shots! The butterfly looks especially good. Matches my experience that the 55-300 is better the closer you get!
02-04-2014, 01:35 PM   #163
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Here is what Ricoh shall announce at CP+:



As you can see, the latest generation of rugged compact cameras will be launched with the Ricoh brand name, not Pentax.

Source : Digital Camera Info

Last edited by Mistral75; 02-04-2014 at 01:42 PM.
02-04-2014, 02:16 PM   #164
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Any idea how long it might be between the TC announcement and getting one in my hand? I have a trip coming up at the end of March and I will be extremely disappointed if I have to make do without the extra reach.
02-04-2014, 04:19 PM   #165
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I find the Pentax 1.7AF works fine on the K5II- DA* 300,actually focus is faster,also using a battery grip,sharpness is not so bad ,but wonder/hope the new one will be even better...
also I never got good results with a zoom & tc..must be a good prime
also the DA*300+1.7 works on the Q ,but hard to keep still at that focal length!!
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