[Ducatigaz]

This PM I tried it again at a bird feeder, and I took 50 shots, between f5.6 and f11, 1/800 to 1/6000, iso 100 to 400, and none of them were sharp, except the ultimate shot I decided to take with the flash at 1/6000 F11 ISO400 that is acceptable...
It was a bit cold outside (-7C), but not that bad (I let the lens acclimate to the cold gradually in the case in my car for a while to make sure that there was no haze cause by possible condensation, and I always do the same thing with my FA250-600, idem for when I go back home... and there always a lot of silicagel pouches in the case to absorb any humidity).
I dont know if something could have happened in the shipping... or before, because that lens used to be dropped, because the lens hood has been notched (attached the photo from the listing)... Also, the screw drive system is doing a strange noise, especially under the cold (my 250-600 doesn't do that) so.... anyways, I am giving up on that lens and going to return it...I contacted the seller, and requested a return that was accepted
Yesterday I thought that I would maybe be better get the DA560F5.6 as a fixed long focal for the better portability, speed, and digital design and price advantages...
Thanks to all for your advices, I learned a lot again because of you and I appreciate very much all your knowledge!

Looking at the picture that you posted and comparing it to my 600mm either the hood goes back further than mine or the filter [which is one of the lens elements] is not screwed right home.
On my copy I can only see the edge of the filter.

[Weevil]

Could be... I'll pm you on that...

Well at least you get to return it.
No interest in the Sigma 500/4.5

[Weevil]

FYI, this is the noise I was talking about
https://picasaweb.google.com/114227534831015179379/FA600Video?authuser=0&aut...eat=directlink

[Lowell Goudge]

I know this is perhaps a silly question, but has anyone thought to check the slid in filter. It is needed in the optical path to get optimum focus. If it has been replaced or is not installed in the hole it could really impact sharpness

[dadipentak]

I know this is perhaps a silly question, but has anyone thought to check the slid in filter. It is needed in the optical path to get optimum focus. If it has been replaced or is not installed in the hole it could really impact sharpness

Not silly at all!

[vonBaloney]

I know this is perhaps a silly question, but has anyone thought to check the slid in filter. It is needed in the optical path to get optimum focus. If it has been replaced or is not installed in the hole it could really impact sharpness

Is it needed? (I usually take it out of my A*600/5.6 for shooting.)

[dadipentak]

Is it needed? (I usually take it out of my A*600/5.6 for shooting.)

For many lenses it's absolutely critical. For some reason there may be some copy-to-copy variation in its impact on IQ. There's extended discussion of this buried deep in the archives of the "300mm &+ lens club."

[vonBaloney]

For many lenses it's absolutely critical. For some reason there may be some copy-to-copy variation in its impact on IQ. There's extended discussion of this buried deep in the archives of the "300mm &+ lens club."

Yes, and for many it is not and they perform are fine with no filter (and on a few, you might lose infinity, but it is better without it, and how often do you go to infinity on a ultra-tele unless you're shooting the moon?). Just wondering which it is -- on the Pentax A*300 & A*600 which I've used, removing the filter is no problem. Same with the other drop-in filter long lenses I've used, which were Tamron Adaptalls. But those are all manual-focus. But it seems like an AF model would (potentially) be ok also as long as it could focus. Maybe not. (I'll dig into that thread. Always curious about such things, although I've found what people say to be true, and what is actually true when you try it yourself to be quite divergent.)

[Weevil]

I know this is perhaps a silly question, but has anyone thought to check the slid in filter. It is needed in the optical path to get optimum focus. If it has been replaced or is not installed in the hole it could really impact sharpness

Not silly question indeed...
Yes I did checked it (and cleaned it because it was dusty) and I made sure it was inserted the right way (arrow of the holder pointing toward the camera when in place... same as my 250-600, and same as indicated on the CPL drop-in filter).

---------- Post added 2016-01-25 at 23:27 ----------

Yes, and for many it is not and they perform are fine with no filter (and on a few, you might lose infinity, but it is better without it, and how often do you go to infinity on a ultra-tele unless you're shooting the moon?). Just wondering which it is -- on the Pentax A*300 & A*600 which I've used, removing the filter is no problem. Same with the other drop-in filter long lenses I've used, which were Tamron Adaptalls. But those are all manual-focus. But it seems like an AF model would (potentially) be ok also as long as it could focus. Maybe not. (I'll dig into that thread. Always curious about such things, although I've found what people say to be true, and what is actually true when you try it yourself to be quite divergent.)

Interesting, let us know what your findings are... especially on the FA*

[Lowell Goudge]

Yes, and for many it is not and they perform are fine with no filter (and on a few, you might lose infinity, but it is better without it, and how often do you go to infinity on a ultra-tele unless you're shooting the moon?). Just wondering which it is -- on the Pentax A*300 & A*600 which I've used, removing the filter is no problem. Same with the other drop-in filter long lenses I've used, which were Tamron Adaptalls. But those are all manual-focus. But it seems like an AF model would (potentially) be ok also as long as it could focus. Maybe not. (I'll dig into that thread. Always curious about such things, although I've found what people say to be true, and what is actually true when you try it yourself to be quite divergent.)

I recall the original tamron 300/2.8 where the iq dropped hen the filter was installed because the designer forgot about the filter in the original design. Later tamron 300/2.8's absolutely needed it to be sharp.

I need to play with my 200-500/5.6 to see whether it is better with or without the filter

[vonBaloney]

I recall the original tamron 300/2.8 where the iq dropped hen the filter was installed because the designer forgot about the filter in the original design. Later tamron 300/2.8's absolutely needed it to be sharp.

I need to play with my 200-500/5.6 to see whether it is better with or without the filter

Yeah, I've heard that, and I've not used any of the Tamron 300/2.8s, but I had the 400/4 and the 200-500/5.6, and from what I remember didn't notice much difference with or without (I think the zoom might have needed it at certain settings). But I did end up leaving them in so maybe I did notice something and am just misrembering. Of course, it was always with APS-C cameras that I've used these lenses -- could more more aberrations on the unseen edges that I don't know about. (On the Tamrons, I saw a definite lessening in aberrations and sharpness by not using the front "normal" filter, but I also read somewhere that THAT filter increased sharpness as well, which it certainly did not. The 200-500 zoom is particularly prone to purple fringing, and that was helped by removing the front filter) The Tamrons are different than the Pentax models (at least the primes, not sure about the 200-500?) in that the drop-in filter goes in-between elements, whereas on the Pentax long teles I've used the filter IS the rear element (and is rear of the aperture).

In any case I've generally removed the filter when using the Pentax-A* 300/2.8 & 600/5.6 to no ill-effect and I think slight improvement -- they are sharp as hell anyway, even wide-open (fringe a bit maybe at max aperture, but plenty sharp). I would think the same would be true of the FA* unless it indeed messes up autofocus. But wouldn't the *specific* filter used make a difference if it was that sensitive? After all, that's what it is there for -- to give you filter options. (I wish the A* models had the little wheel for spinning a polarizer -- been trying to figure out how to rig something up to do that.)

[pete-tarmigan]

Is it needed? (I usually take it out of my A*600/5.6 for shooting.)

The instruction manual says it's not needed for the A* 600mm f/5.6 and other A* super-telephotos. Drop in filters weren't included with those lenses.

http://ricoh-imaging.ca/pdf/o_manuals/om_A300MM400MM600MM1200MM_e.pdf

[dadipentak]

The instruction manual says it's not needed for the A* 600mm f/5.6 and other A* super-telephotos

Huh! I know one guy who found it was absolutely essential for his copy of the A*400/2.8.

[vonBaloney]

The instruction manual says it's not needed for the A* 600mm f/5.6 and other A* super-telephotos. Drop in filters weren't included with those lenses.

http://ricoh-imaging.ca/pdf/o_manuals/om_A300MM400MM600MM1200MM_e.pdf

WELL! If we're going to break down and consult the manual... it actually doesn't say it is needed or not needed, it just says how to use it. And just now consulting the manual for the F* 600/4 (not FA, but they are the same optically I think?), I see that it doesn't say much about it either (again other than how to take it in and out). However, I guess that lens came with a filter and maybe the A*s didn't (although mine came used with a Pentax-branded filter). And the F manual DOES specify that the front filter is to be considered part of the optical system and should be left in place, so there's that...


PENTAX SMC F 600MM F/4 ED (IF OPERATING MANUAL Pdf Download.

[Pål Jensen]

My 600/4 has been behaving strangely (for me). My review of this lens in the review section on this forum is based on film use, where it is softer wide open than stopped down to F:5.6 but still adequately sharp wide open (see photo).
However, I was not able to get any sharp images with the K10D and this lens. I tried everything like focusing bracketing, multipoint support and long shutterspeeds (minutes) in conditions with no wind. Everything was fuzzy - completely useless.
On the K-7 images shot at, say, a 100m or closer was perfectly fine. But I couldn't get a single sharp image at or near infinity. It wasn't a case of the lens not being able to focus at infinity; it focuses past infinity. I tried everything to exclude vibration, focusing errors (focus bracketing) etc.
The lens works just fine on the K-3! just like on film cameras. Haven't tried it wide open though as I prefer to use it stopped down to minimize potential focusing errors and higher ISO setting.
I used manual focusing on all these tests.
I find it baffling and have no explanation.

The image below is shot wide open with the 1.4X-L converter on film (Provia 100F)
Second image wide open. (Provia 400F at 800ISO)