Wide Angle for Phase One DF.

[ondebanks]

Is there anything from another manufacturer that I can use on the Phase One DF that might give me good quality? I am not familiar with what is available in terms of adapters.

There are adapters for the lenses of several 6x6 and 6x7 systems - Hasselblad, Bronica, Pentax, Pentacon/Kiev -, but the problem is that none of them have a rectilinear lens shorter than 40mm. There are some adaptable 30mm fisheyes for 6x6, but if I were going the de-fishing route I would definitely prefer the Mamiya 24mm that I've discussed above.

One of the older Pentax 645 35mm variants is said to be really good, and there's a new 25mm lens; on paper, there is enough flange distance difference (over 7mm) to adapt them onto the Mamiya/Phase body and still reach infinity focus, but I've never seen such an adapter being made available.

Ray

 

[synn]

I use the Mamiya 35mm on the Credo 40. As I am mostly a portrait guy, this is just about wide enough for my environmental portrait needs. Obviously, you'll get a much wider FoV with a 60MP sensor.

With the Credo 40, I have noticed that this lens has extremely sharp center (Comparable to the 80mm LS, one of the sharpest lenses out there) and somewhat soft corners. The corners do get better when stopped down to f/87-f/11, but not as sharp as the center. However, in Capture One Pro, there's a tool to increase only the corner sharpness. With this, you can get the corners to look as good as the center.

Here's a full size sample that I shot for your reference. Shot with a 3 stop Lee grad ND on the lens.

http://farm4.staticflickr.com/3803/12266936635_4b0b8f738b_k.jpg

 

[GrahamWelland]

What everyone said above - basically it's difficult with any medium format lens to create great wide/super-wide lenses for a full 645 sensor. The 35 D I have only seems to differ from the AF version I used to have by a silver ring and nice Phase One lens wrap. I hear that build/test tolerances were better but that might just be marketing BS.

One of my favorite and most printed images was taken with the 35 D on a wet day with my DF/IQ160 and whilst not technically perfect in the corners it doesn't matter a jot because (a) I had the lens with me, (b) the composition worked and (c) I was able to polarize the lens for wet foliage which was something that would've ruined the same shot with the 28mm.

Another wide I like is the 45mm too. Another Mamiya vintage lens that isn't half bad in reality. (55LS smokes them all though).

I think that many of us pine for Schneider to help Mamiya/Phase with a great super wide and/or tilt/shift wide. I would raid my piggy bank for one of those and probably use my DF body more if a great wide existed that was even 90% as good as a tech wide. (Ok, that's unfair as they probably ARE 90+% as good - make it 95%!)

 

[gerald.d]

One option that hasn't been mentioned so far would be to get hold of the Mamiya 24mm fisheye and de-fish your shots.

I've found the image quality with that lens to be excellent.

Kind regards,

Gerald.

 

[D&A]

As Ray has noted these two things in his posts above:

1. --->>>"The main problem with the 35/3.5 lens - which is optically unchanged (bar coatings) from the first "C" version in the late 1970s, through the "N" version of the mid-1980s and the "AF" version of the late 1990s, and also probably the "D" version of the late 2000s - is field curvature. In a shot of a 3-d landscape, you can actually see the "plane" of focus start off on distant central objects and then bend back towards closer objects off-axis. The only way to get decent focus on distant things off-axis is through depth of field i.e. stopping down a lot, as Graham says.<<<

2.--->>>"One of the older Pentax 645 35mm variants is said to be really good, and there's a new 25mm lens; on paper, there is enough flange distance difference (over 7mm) to adapt them onto the Mamiya/Phase body and still reach infinity focus, but I've never seen such an adapter being made available.<<<

Therein lies the problem of adapting the Pentax FA 35mm f3.5 645 lens. It too exhibits a health dose of field curvature when focused on distant subjects and behave in much the manner as described above for the Mamiya 35mm f3.5 lens. Other than that it's extremely sharp centrally and across the frame when lens is well stopped down.

Dave (D&A)

 

[ondebanks]

One option that hasn't been mentioned so far would be to get hold of the Mamiya 24mm fisheye and de-fish your shots.

I've found the image quality with that lens to be excellent.

Kind regards,

Gerald.

Umm, I mentioned de-fishing the 24mm twice, before you did! Posts #12 and #21. :grin:

I agree, superb lens.

Ray

 

[ondebanks]

As Ray has noted these two things in his posts above:

1. --->>>"The main problem with the 35/3.5 lens - which is optically unchanged (bar coatings) from the first "C" version in the late 1970s, through the "N" version of the mid-1980s and the "AF" version of the late 1990s, and also probably the "D" version of the late 2000s - is field curvature. In a shot of a 3-d landscape, you can actually see the "plane" of focus start off on distant central objects and then bend back towards closer objects off-axis. The only way to get decent focus on distant things off-axis is through depth of field i.e. stopping down a lot, as Graham says.<<<

2.--->>>"One of the older Pentax 645 35mm variants is said to be really good, and there's a new 25mm lens; on paper, there is enough flange distance difference (over 7mm) to adapt them onto the Mamiya/Phase body and still reach infinity focus, but I've never seen such an adapter being made available.<<<

Therein lies the problem of adapting the Pentax FA 35mm f3.5 645 lens. It too exhibits a health dose of field curvature when focused on distant subjects and behave in much the manner as described above for the Mamiya 35mm f3.5 lens. Other than that it's extremely sharp centrally and across the frame when lens is well stopped down.

Dave (D&A)

Thanks for that additional info, Dave - useful to know. Yeah, I remember now that it's the FA version that is supposed to be best. Links like this sing its praises.

Interestingly, down at the end of that page he addresses the practicalities of adapting it (permanently) to the Mamiya mount: "I can see that it is feasible, but may require a minor mirror mod to the Mamiya body. It also entails the removal of the FA35's rear mount and it's not easy to disentangle the aperture and AF mechanism from the bits you need to discard. Wearing a donor Mamiya mount, the rear element needs to protrude beyond the flange to provide correct infinity focus... got close enough to see that it's a viable concept that I would have seen to completion had I stuck with the body".

That all sounds very surprising: rather than insert a ring about 7.5 mm thick between P645 lens and M645 mount (70.87 mm and 63.3 mm flange distances respectively), he is talking about hacking off the back of the P645 lens and having its rear element protrude through the M645 flange, and modifying the Mamiya's mirror? Given the relative flange distances, that doesn't make sense to me. I'm going to email him for an explanation...

Ray

 

[gerald.d]

Umm, I mentioned de-fishing the 24mm twice, before you did! Posts #12 and #21. :grin:

I agree, superb lens.

Ray

Oops, my sincere apologies. I rather stupidly just did a search for "24", and nothing came up, so I assumed it hadn't been mentioned. Should have searched for "24mm", or perhaps even better, not been so damn lazy as to not read the full thread!

Kind regards,

Gerald.

 

[alajuela]

Hi

I have several questions, how do you go about de-fishing the fisheye?
What are the software options?
Does it degrade the file?
Do you do it in a raw converter or as a tiff?

Thanks so much

Phil

 

[ondebanks]

Oops, my sincere apologies. I rather stupidly just did a search for "24", and nothing came up, so I assumed it hadn't been mentioned. Should have searched for "24mm", or perhaps even better, not been so damn lazy as to not read the full thread!

Kind regards,

Gerald.

No worries Gerald; I was tickled rather than annoyed.

Ray

 

[ondebanks]

Hi

I have several questions, how do you go about de-fishing the fisheye?
What are the software options?
Does it degrade the file?
Do you do it in a raw converter or as a tiff?

Thanks so much

Phil

Hi Phil,

There are a few software options. I use Hugin, which is a nice interface to Panotools. This requires tiff/jpeg/png/hdr/exr input formats; not raw, unfortunately.

Image quality in the centre is maintained; the de-fishing re-projection does tend to make the edges a bit less sharp (due to the relative lack of resolution in this area in the original fisheye projection). The original corners of the fisheye area are automatically cropped off anyway (if you choose; otherwise the image looks like a pincushion with curved black borders).

There are a host of re-projection options that can be previewed and used; Rectilinear and Panini projections work well.

Ray

 

[alajuela]

Hi Phil,

There are a few software options. I use Hugin, which is a nice interface to Panotools. This requires tiff/jpeg/png/hdr/exr input formats; not raw, unfortunately.

Image quality in the centre is maintained; the de-fishing re-projection does tend to make the edges a bit less sharp (due to the relative lack of resolution in this area in the original fisheye projection). The original corners of the fisheye area are automatically cropped off anyway (if you choose; otherwise the image looks like a pincushion with curved black borders).

There are a host of re-projection options that can be previewed and used; Rectilinear and Panini projections work well.

Ray

Thanks Ray

I have auto panogiga from Kolor, I assume then; that would work. Thanks so much, - Thinking if I could find the fish eye at good price, maybe it might be fun.

Thanks again

Phil

 

[ondebanks]

:worthless:

Here's an example of defishing the 24mm.

I don't do architectural or interiors photos; this was just a shot I had taken to document the completion of our home extension. I thought it would make a good example for this thread, as there are many demanding straight lines. I used Hugin to simultaneously defish and correct a tiny bit of camera tilt.

The resulting field of view is ~ 90x90 degrees.

Ray

 

[alajuela]

Hi Phil,

There are a few software options. I use Hugin, which is a nice interface to Panotools. This requires tiff/jpeg/png/hdr/exr input formats; not raw, unfortunately.

Image quality in the centre is maintained; the de-fishing re-projection does tend to make the edges a bit less sharp (due to the relative lack of resolution in this area in the original fisheye projection). The original corners of the fisheye area are automatically cropped off anyway (if you choose; otherwise the image looks like a pincushion with curved black borders).

There are a host of re-projection options that can be previewed and used; Rectilinear and Panini projections work well.

Ray

:worthless:

Here's an example of defishing the 24mm.

I don't do architectural or interiors photos; this was just a shot I had taken to document the completion of our home extension. I thought it would make a good example for this thread, as there are many demanding straight lines. I used Hugin to simultaneously defish and correct a tiny bit of camera tilt.

The resulting field of view is ~ 90x90 degrees.

Ray

Very nice - Hugin does a good job, Kolor Auto Pano I hope is as good. -- BTW nice addition to your home - lots of sunlight

Phil

 

[ondebanks]

-- BTW nice addition to your home - lots of sunlight
Phil

That's the theory anyway, Phil. In practice, we are rather starved of sunlight here on the west coast of Ireland...

Ray