[shaolen]

Will using the 50-135mm on the HD 1.4 teleconverter allow it to cover FF? I heard doing this with the DA 70mm limited worked.

[Blacknight659]

I am interested in what answers you get on this. I was wondering what my 50-135 would look like on the new FF Pentax. I figured I would just use in in Crop Mode if I had to.

[jeffryscott]

I'm also curious how this combo compares to the 60-250 IQ-wise.

[npc]

Few months ago I borrowed the HD 1.4 teleconverter for a couple of days and briefly tested the coverage on Sony A7R.
Didn't try the DA* 70 but it fully covers FF without the TC , so I guess it will work with the tc as well.

From what I remember:

DA* 50-135 + HD 1.4x fully covered FF trough the whole range (and I did not pixelpeep too much since I just wanted to check the coverage/vingeting, but picture quality seemed pretty good)

DA* 60-250 + HD 1.4x - was actually worse, darker corners than using the lens alone. Strange, since when used with no teleconverter it has much better FF coverage than 50-135. I've noticed the 60-250 has a baffe on the back side which might be causing the vingeting/dark corners (on FF), so maybe if removed it will completely cover FF.

I've tested few others that I had with me as well but I don't remember the details anymore, except that the 35 ltd macro looked very good, athough I guess it makes little sense to use it that way.

[shaolen]

wow thanks for that. So this might be a viable inexpensive option to get a near 70-200 equivalent!

[Mikesul]

I had similar results and I also tested the TC with the DA*300 on a A7RII. I was disappointed to find that the 300 vignetted with the TC. I plan to test this again but it seemed to be present at all apertures. Without the TC the DA*300 covered the FF circle without problems. On a Pentax FF I imagine/hope the camera will correct the vignetting. That is my interpretation of the Ricoh/Pentax executive comments in February (god that is a long time ago!).

[Blacknight659]

I think it is a crop mode, but what i dont understand is how they can crop the image in the view finder. If they use a standard mirror, they would need crop lines, if they use a digital view finder it wouldnt feel like a traditional pentax. All things to ponder.