[Bob from Aus]

I wanted the new pentax 1.4 TC for my 60-250 for some extra reach when I can't carry anything larger. I'm very happy with the sharp photos from my 60-250. Autofocus with the TC seems to be fine, but need to test for back focus. With the TC I don't seem to get a great amountof detail - but maybe that is just the winter light. I seem to have the same result with the K5 and the K3

Some questions.
Do I need to upgrade my camera firmware?
Would a TC produce back focus problems?
Am I expecting to much? (for $600 I expect a lot)


From what I've read others have found minimal degradation.

Have just taken jatax suggestion and upgraded firmware.
I chosen some different life subjects and I seem to have a back focus issue where I didn't have one before with the lens on its own.
I will keep experimenting and taking on board your suggestions.

Fix ended up being getting the Auto focus adjusted on my K3 and pentax 60-250 zoom

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Last edited by Bob from Aus; 09-05-2014 at 12:18 AM.

[JayBee451]

I seem to recall that a software update was needed for the 1.4 TC, so try that first and I'm sure you will be happy again.

[jatrax]

Most other folks report they are happy with it. I believe the TC was added to a recent firmware update so that is the first thing I would check.

Also, the TC is supposed to register in AF fine tuning as a new lens with each lens you use it with. So if you have an AF fine tuning set for the 60-250 you should also set one for the 60-250 plus TC.

Note that the above is just gleaned from other threads, I do not have the 1.4x TC but it is high on my list and I've been following comments on it closely.

[derekkite]

I wanted the new pentax 1.4 TC for my 60-250 for some extra reach when I can't carry anything larger. I'm very happy with the sharp photos from my 60-250. Autofocus with the TC seems to be fine, but need to test for back focus. With the TC I don't seem to get a great amountof detail - but maybe that is just the winter light. I seem to have the same result with the K5 and the K3

Some questions.
Do I need to upgrade my camera software?
Would a TC produce back focus problems?
Am I expecting to much? (for $600 I expect a lot)


From what I've read others have found minimal degradation.

I think you are running into not enough light. You lose a stop. I fought with it for the first few months; mounts that worked fine with 300mm vibrate with the TC. That stop of light that it takes has to come from somewhere, usually iso, with loss of detail.

I think you need to take it off for a month or so and wait for some light.

[ElJamoquio]

F/5.6 is not a ton of light for a 350mm lens with a 24MP APS-C sensor.

The TC could definitely produce back focus problems.

I don't have your TC or your lens, but depending on the light path that Pentax intended for the 60-250, it might not be a good match for the T/C. Generally zooms don't pair as well with T/C's as primes... but people with your combo seem happy, so I dunno.

I would definitely upgrade the camera to the latest software.

[crewl1]

There is a requirement to hold the lens a little steadier with the 1.4 on than without it.

When I use the *300 for a while I have to be conscious to hold the setup more carefully when I add the 1.4 or my shots can look soft.

F6.3 seems optimal with the 1.4 on.

If you have been only using it hand held, try a tripod and see if results improve.

[jpzk]

I have the TC (on the K5) for a couple of weeks and paired with the DA*300/4.

I found:
1. At f5.6 shots are great as long as I don't underexpose.
2. unlike crew1 above, the fine spot is still f5.6
3. I use TAv all the time
4. A bit tougher to handle (hand held - I don't use a tripod often), like any long lens, especially with the TC attached but overall quite good as long as I keep my speed up to reasonable levels.

I did do the firmware update before testing the TC with that lens ...
So far so good but as someone else mentioned earlier, maybe you'd need to get the back focus thing out of the way with some fine adjusting?

JP

[jbinpg]

I shoot a lot with the 1.4 TC + DA*300, I needed to adjust the AF +3 with this combo compared to just the DA*300. Remembering the initial 1.4 TC threads, this was a common occurrence.

Jack

[Bob from Aus]

I shoot a lot with the 1.4 TC + DA*300, I needed to adjust the AF +3 with this combo compared to just the DA*300. Remembering the initial 1.4 TC threads, this was a common occurrence.

Jack does that mean that the backfocus has to be adjusted each time one swaps between the TC and the lens?

[derekkite]

Jack does that mean that the backfocus has to be adjusted each time one swaps between the TC and the lens?

I believe that the lens adjustment can be set for the TC.

Mine matches the lens itself, ie. if the lens alone needs +4, the lens plus tc needs +4. If it is too far off, I'd get a replacement. It should simply pass on what the lens is doing.

[zapp]

I want a 2.8/300 or 2/200 or 2.8/80-200 before getting a 1.4 converter. In the current linup a 1.4x TC is quite pointless - 2x would be worse though.

[jbinpg]

The lens + TC combo is seen by the camera body as a separate lens so you can store separate settings for the combo or just the lens. The camera will know the difference and choose the proper AF adjustment.

Jack

[audiobomber]

I want a 2.8/300 or 2/200 or 2.8/80-200 before getting a 1.4 converter. In the current linup a 1.4x TC is quite pointless - 2x would be worse though.

I disagree. The 1.4X turns my DA*300 into more than a match for the Canon 400mm f5.6. The reason I said more than a match is because the Canon lens doesn't have a SR, and can't be used as a 300mm f4.

The 1.4X should be a nice complement to the DA*200mm. It is also highly useful mounted on a D FA 100mm macro for extended reach or boosted magnification (1.4:1). Actually any macro lens would benefit in the same way, especially the DA 35mm macro, so you can gain some subject distance.

To Bob from Aus, sorry to hear you're having trouble. I am very happy with my HD 1.4X RC.

[Driline]

I disagree. The 1.4X turns my DA*300 into more than a match for the Canon 400mm f5.6. The reason I said more than a match is because the Canon lens doesn't have a SR, and can't be used as a 300mm f4.

The 1.4X should be a nice complement to the DA*200mm. It is also highly useful mounted on a D FA 100mm macro for extended reach or boosted magnification (1.4:1). Actually any macro lens would benefit in the same way, especially the DA 35mm macro, so you can gain some subject distance.

To Bob from Aus, sorry to hear you're having trouble. I am very happy with my HD 1.4X RC.

Your answer is vague. How is comparing the TC to Canon relevant? The original op is having problems with image clarity.
Maybe you could post some pics taken with your TC and DA*300 for reference.

[Bob from Aus]

It is also highly useful mounted on a D FA 100mm macro for extended reach or boosted magnification (1.4:1)

I've tried Audiobomber's suggestion of using the TC with a 100mm WR macro. I used flash and large softbox so my aperture was around F10 to14. I got a lot of sharp images where it was in focus. So the TC can take sharp images. Its my 1.4 Tc and 60-250 combo that is the problem. I have adjusted back focus by +4 for 60-250 combo but still not happy.