[Hannican]

In otherwords...

If we all buy DA lenses, and Pentax puts out a full-frame camera, will we all need to buy the NEW full-frame DA (whatever they'll be called) lenses, or be SOL?

Just wondering...

-Tim

[Canada_Rockies]

In otherwords...

If we all buy DA lenses, and Pentax puts out a full-frame camera, will we all need to buy the NEW full-frame DA (whatever they'll be called) lenses, or be SOL?

Just wondering...

-Tim

Actually, Pentax built the full frame lenses first. They are called FA or D-FA lenses.

[Hannican]

DFA I was wondering if those were full frame supportive...

But still, if we buy DAs and then want to move to full frame... will DAs work?

-Tim

[Canada_Rockies]

DFA I was wondering if those were full frame supportive...

But still, if we buy DAs and then want to move to full frame... will DAs work?

-Tim

The lenses will work, but they will not cover the full frame. They will vignette. Some don't vignette at the longest focal lengths, but all will vignette at the wider focal lengths (zooms). I suspect that the primes will all vignette. The circle produced behind the lens is not large enough to cover the 24x36 mm frame. It is designed to cover the roughly 12x13 frame of the sensor. This allows the lens to be quite a bit lighter than the full frame lens of the same focal length and speed.

Edit: Oops, that sensor size is obviously incorrect - try "about 16 X 24"

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Last edited by Canada_Rockies; 12-14-2007 at 12:22 AM. Reason: Dumb sensor size

[Hannican]

I see...

Thank you for the information!

I'm not sure how it will affect my purchasing decisions, if at all, but I feel better knowing this.

Thanks again Albert

-Tim

[Finn]

Actually, the DA40 WILL work with a 35mm-sized sensor because it is the same design as the old M 40mm.

[welshwizard645]

The one obvious difference between D-FA and DA is that the D-FA has an aperture ring...

[baldeagle21b]

Perhaps when Pentax releases a FF camera a APS-C mode will be provided as an option to allow use of the DA lenses without vignetting.

[kb244]

Actually, the DA40 WILL work with a 35mm-sized sensor because it is the same design as the old M 40mm.

I wondered about that, its probably the same optical construction in terms of what glass goes where. But clearly the DA40 is worlds sharper than the old M40. But I can confirm that the DA40 works on a film body. However it needs to be a film body that has electronic contacts (Kaf) and the camera must be able to allow you to manually input an aperture from the camera itself, as you don't have an aperture ring. It seems plenty of the electronic film cameras cut cost on the body by pretty much assuming it would be redundant to offer any other means to control a lens aside from the aperture ring. As such it seems the PZ series and newer (the SF-1 wouldn't work and some others I tried) will work with the DA40 without worry that it'll always stop down to f/22 whenever you fire a shot.

The other lens definitely will vignette, tried a 16-45, you could clearly see the fall off at 16 to 20, though not as noticeable in the viewfinder at around 21-22. It is at least however a softer falloff than say other brands of lens designed for digital, such as the Tamron Di-II, or the Canon EF-s which will have a much sharper circle outline at any focal length, since the back element is cut to size as well. Being designed for digital also means that even if you start reducing the vignetting, the edge sharpness and quality might suffer greatly as they had no reason to design it for crisp edge to edge on the whole surface of the glass.

But looking at the lens line up, I can't imagine a full frame variation is in the market any time soon for pentax, but for the film lovers theres always the FA and older mounts, at least they're the only company that makes DSLR with the best backward compatibility across all of its models. Myself if I got another DA lens it would be strictly for the digital, otherwise I'll concentrate on FA lens as I do plan on getting a better film body.

[kb244]

Perhaps when Pentax releases a FF camera a APS-C mode will be provided as an option to allow use of the DA lenses without vignetting.

Very doubtful, even if they did release a full frame camera, the DA lens problem is a physical limitation as it was only designed to cover the APS area. IF pentax releases a full frame camera, they'll probably do so in the same manner that Nikon did releasing new lens designations (kinda like FA, but maybe call it FA2 or FX who knows) for both format.

But least with the Nikon full frame camera, it'll auto-crop the sensor (lower megapixels obviously) for the DX lens coverage, which not even the Canon full frame bodies do (course most of their EF-s lens also protrude back into the camera body making it difficult to make it fit into a full frame body). Perhaps pentax might follow the same route, and you would just have to use a full frame lens to utilize all the pixels on the camera sensor.