*ist lens compatability

Am trying to find out if my Tokina KA mount lenses will work on the *ist. I am currently using htese on my ZX7 body. Will I beable to use all the functions or do I need a FAJ lens to do that?

The KA lenses can be used and will provide the features that you have at present when the approriate custom function is selected on the *ist. (That is, the one that provides use of the aperture ring). FAJ lenses will be needed to fully employ all *ist functions.

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Best regards, John

Thanks john, am looking at a 28-100 FAJ.

Hi all

I thought that the faj lenses were basically the same as the fa range but pemanently set to "A" and that any other AF pentax or generic lens set to "A" would peform exactly the same can this be confirmed or denied?

regards mark

Thats true. They are the same and have no manual adjustment.
To use a AF lens on the *ist you have to leave it on A setting and NOT use the aperture ring, but do it all from the camera body; if you do use the ring it won't read the lens 'f number'. Conversely, the new lens will only work on A setting - and so older cameras with non-electronic Depth of Field preview buttons won't work with the new style lens.

Armourermike

Hello Everybody!

I have a Pentax ME Super that already "lived it's life" and want to buy a new *ist. I wonder if my ME lenses will fit the *ist. I've got 3 lenses:

Pentax 50mm / f1.4
Tokina 60-300mm / f4-5.6
Sigma 35-135mm / f3.5

On the Tokina lens, there's in inscription that writes: P/K-A R-P/K
The other 2 lenses have got no inscriptions. The mounts of all 3 lenses look the same. All of them have an appature ring.

Thank you in advance.

Vidu Gunaratna
Czech Republic

Hello Vidu!

All of the lenses will fit, and can work.

However, the *ist is meant to work only with lenses that have an green "A" mark on the aperture ring. If your lenses only have the numbered f-stop selections, they will not be too easy to use.
If you do use them, I believe you have to setup a custom setting (as you do on the digital *istD), but it is really not a comfortable way to use the camera At the very least, I think it can behave like the ME Super, but once you get used to the automatic settings, you will wonder how you managed before

Hope that answers your question,
Matt

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http://www.mattmatic.co.uk
(For gallery, tips and links)

Dear Matt,

Thank You for the quick answer! So what is the catch with the lenses without the A non the ap. ring? My 50/1.4 is that case and I really like that lense for obvious reasons...

Thank You!

Vidu

Lenses with an 'A' setting will also have the necessary electronic contacts on the mount to enable the camera to control the aperture value of the lens. In effect, the *ist makes the manual settings on the aperture ring redundant.

If you really want to set aperture values on the lens, then perhaps look at the MZ-5n, MZ-3 or MZ-S instead. I use the MZ-3 for this reason and for its conventional shutter speed dial. When I want it to, it handles just like my MX.

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Best regards, John

I am using an "A" lens with the *ist D (Pentax 20mm A f/2. and there are two concerns.

Firstly, the focal length is not recorded with the image information. In fact, the cameras chooses the highest possible shutter speed defaulting to thinking it is a telephoto lens!

Secondly, all images are overexposed by one stop. Easy to allow for, but why?

Could both the concerns indicate something wrong with the lens?

However, after making the one stop adjustment I'm getting consistently good results with the lens acting as a 30mm prime.

Does anyone else have this camera/lens combination to compare results?

Hi Malcolm,

The non-autofocus lenses, and all lenses without electronic contacts cannot tell the body what they are

If it is pushing the shutter speed up - are you using the program line "Hi Speed"? If so, try using "Normal" - that should pick a sensible shutter speed/aperture combination.

As to the exposure issue... not sure about that. I have the Pentax Auto Extension tubes, which have no contacts, and they work a treat. However, when using them I do have to set up some custom functions to use them.

Matt

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http://www.mattmatic.co.uk
(For gallery, tips and links)

Hi Matt

Thanks for the reply and helpful comments.

Regarding the overexposure, I already have the Custom Function set at "Normal". The iris is perfectly free and is not in the least bit sticky. However, the return spring of the diaphram lever is stronger than that on the 18-35 FA-J lens. Would a slightly stronger return spring affect exposures? I would have thought that a stronger spring would reduce, not increase, exposure.

Anyway, thanks for putting my mind at ease regarding the focal length issue.

Can they be used? Any experience reports welcomed.
Bob

I think they cannot be used on the *ist.

The *ist and the *istD are different.

The *ist cannot determine the aperture setting of a K or PK lens. The *ist can only work with lenses that have the electrical contacts and the Auto Aperture (Green A) setting. It uses totally the wrong exposure with other lenses.

The *istD with the latest firmware (downloadable from the Pentax site) can use these lenses.

Why the *ist cannot have this firmware upgrade defeats me, but that is the situation.

Taliety

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Cheers

Malcolm

Life? Don't talk to me about life!