[BostonUKshooter]

Anyone have good experience with manual 'de-fish' software for MF fisheye lenses?..... especially for those without pre-calculated profiles (eg Hartblei/Pentax 67)?....recommendations?....I read that DxO ViewPoint 2 is a good option, but they are currently in bankruptcy administration!
Thks...

[obsolescence]

I have DxO Viewpoint 2 and VP3, which are very useful for perspective as well as FE correction. I don't have a MF camera (yet), but Viewpoint works easily and brilliantly with other camera formats' FE captures. I use VP2 integrated in OpticsPro 10 Raw processing. Rectilinear distortion is almost completely gone and progressive edge sharpening further improves the result. I can also set the aspect ratio to "unconstrained" to get the widest possible FOV (much longer in one dimension). OP11 discontinued the integration of VP, and I don't know whether the newer PhotoLab has re-integrated it or not, or whether the distortion correction is available in PL independent of VP. You can download free trial software and see for yourself. I don't see how DxO's bankruptcy interruption should affect one's decision to buy and use it, since your manual defishing will be available indefinitely (as long as your OS supports it). The only thing to be concerned about is possible lack of support for new cameras and lenses, but manual corrections are always an alternative (and may be better, anyway). The sample below was shot on mFT with a Rokinon 7.5mm FE lens.

[jbrill]

...
OP11 discontinued the integration of VP, and I don't know whether the newer PhotoLab has re-integrated it or not, or whether the distortion correction is available in PL independent of VP.
...

Given a licensed ViewPoint 3 plugin, ViewPoint 3 corrections are available in the tool panel (DXO VIEWPOINT) for both OpticsPro 11 (v11.4.2 Build 12373) and PhotoLab (v1.1.2 Build 2793) .

[mattb123]

I use Lightroom 6 for images I make with a Arsat 30/3.5 on a 645D and just use the sliders to manually adjust distortion and vertical or horizontal perspective distortion.

[jbrill]

Perhaps PTLens (PTLens Home Page) would work. The introduction page contains a screenshot showing a radio button for fisheye distortion and the examples page states for fisheye images:

Fisheye images are distinguished by immense amounts of barrel distortion. Special facilities exist in PTLens for converting fisheye images to rectilinear images. In this case no calibration is necessary as sliders are provided for maximum flexibility.

From the main page, there is a link to a likely older page titled Fisheye Defished (Fisheye Defished).

There appears to be a free trial version good for 10 images.

[BostonUKshooter]

I have DxO Viewpoint 2 and VP3, which are very useful for perspective as well as FE correction. I don't have a MF camera (yet), but Viewpoint works easily and brilliantly with other camera formats' FE captures. I use VP2 integrated in OpticsPro 10 Raw processing. Rectilinear distortion is almost completely gone and progressive edge sharpening further improves the result. I can also set the aspect ratio to "unconstrained" to get the widest possible FOV (much longer in one dimension). OP11 discontinued the integration of VP, and I don't know whether the newer PhotoLab has re-integrated it or not, or whether the distortion correction is available in PL independent of VP. You can download free trial software and see for yourself. I don't see how DxO's bankruptcy interruption should affect one's decision to buy and use it, since your manual defishing will be available indefinitely (as long as your OS supports it). The only thing to be concerned about is possible lack of support for new cameras and lenses, but manual corrections are always an alternative (and may be better, anyway). The sample below was shot on mFT with a Rokinon 7.5mm FE lens.

Thks 'Obsolesence' (John?)...I just downloaded VP2 which seems to do all that I want, and the 'unconstrained' view adds a good deal of extra image area....I am intrigued by your reference to 'progressive edge sharpening'....most super-wide lenses are soft(er) at the edges, so any advice on how to sharpen images 'progressively' would be welcome!....do you mean with the LR brush tool?...or graded masked areas in PS?....thks, Ian

---------- Post added 05-24-18 at 06:55 AM ----------

I use Lightroom 6 for images I make with a Arsat 30/3.5 on a 645D and just use the sliders to manually adjust distortion and vertical or horizontal perspective distortion.

Thks Matt - I use LR to fix some images, but I am trying a Canadian lens front screw-on converter (normally used for video cameras) on the 28-45mm DFA that results in a very wide angle image (40% wider than at 28mm), but soft at the edges....thks, Ian

---------- Post added 05-24-18 at 07:01 AM ----------

Perhaps PTLens (PTLens Home Page) would work. The introduction page contains a screenshot showing a radio button for fisheye distortion and the examples page states for fisheye images:

From the main page, there is a link to a likely older page titled Fisheye Defished (Fisheye Defished).

There appears to be a free trial version good for 10 images.

Thks the suggestion - will take a look too...rgds, Ian

[obsolescence]

Given a licensed ViewPoint 3 plugin, ViewPoint 3 corrections are available in the tool panel (DXO VIEWPOINT) for both OpticsPro 11 (v11.4.2 Build 12373) and PhotoLab (v1.1.2 Build 2793) .

Thanks for that update. The initial version 11 had dropped integration of VP.

[Sarnian]

I am trying a Canadian lens front screw-on converter (normally used for video cameras) on the 28-45mm DFA that results in a very wide angle image (40% wider than at 28mm), but soft at the edges...

Sounds interesting; can you share the manufacturer's name?

Thanks

[BostonUKshooter]

Sounds interesting; can you share the manufacturer's name?

Thanks

Hi - it's Cavision, in Vancouver Canada - CAVISION ENTERPRISES LTD
I bought the LWA06X82 w/a adapter lens (around $250) , which as an 82mm screw-thread compatible with the front of the 28-45mm DFA zoom. Its soft at the edges, and needs care when focussing to get the required dof…..I'm still experimenting with it! Rgds.

[Sarnian]

Hi - it's Cavision, in Vancouver Canada - CAVISION ENTERPRISES LTD
I bought the LWA06X82 w/a adapter lens (around $250) , which as an 82mm screw-thread compatible with the front of the 28-45mm DFA zoom. Its soft at the edges, and needs care when focussing to get the required dof…..I'm still experimenting with it! Rgds.

You've reminded me about an Optex 0.7X Wide Angle converter that I have. I must give it a proper test. It also has an 82mm thread (which can also fit on the 33-55mm lens). The Optex also comes with a Super Wide Angle converter lens which the Wide Angle converter fits inside. The front filter size of the Super Wide Angle converter is a Hubble telescope-sized 119mm!

I doubt this combo will give as good results as a well de-fished 30mm Arsat.

[BostonUKshooter]

You've reminded me about an Optex 0.7X Wide Angle converter that I have. I must give it a proper test. It also has an 82mm thread (which can also fit on the 33-55mm lens). The Optex also comes with a Super Wide Angle converter lens which the Wide Angle converter fits inside. The front filter size of the Super Wide Angle converter is a Hubble telescope-sized 119mm!

I doubt this combo will give as good results as a well de-fished 30mm Arsat.

Interesting!....is the edge quality of the Arsat good or just average?....I print large , so looking for good quality across the frame....
I may have to resort to using my 645 lenses on an Cambo Actus Mini with a hi-res mirrorless body (Sony/FujiX)....

[rdenney]

Interesting!....is the edge quality of the Arsat good or just average?....I print large , so looking for good quality across the frame....
I may have to resort to using my 645 lenses on an Cambo Actus Mini with a hi-res mirrorless body (Sony/FujiX)....

Edges of a fisheye lens projection have to be greatly magnified in the sagittal direction to turn it into a rectilinear image. Even good lens performance will be degraded by that. A rectilinear lens performs that magnification optically.

My advice is to use a fisheye lens when you want a fisheye projection, and use a rectilinear lens when you want a rectilinear projection, unless you can tolerate reduced enlargeability.

If you need high-resolution ultrawide rectilinear images and a used 25 doesn’t do it for you, the next step up from that is a digital back on a view camera with a digitally optimized view camera lens. The Cambo Actus gives you some movements, but the Actus 24mm lens is designed for 24x36 sensors. It has coverage for a 33x44 sensor, but without any movements—I see no advantage over a used 25mm DFA. The 23mm Rodenstock Digaron has more coverage, but won’t fit in front of even a small-format mirror box. It needs a real digital back.

https://www.bhphotovideo.com/c/product/637020-USA/Rodenstock_150120_23mm_f_5...981&

Rick “who has been using an Arsat fisheye for nearly 20 years” Denney

[BostonUKshooter]

Edges of a fisheye lens projection have to be greatly magnified in the sagittal direction to turn it into a rectilinear image. Even good lens performance will be degraded by that. A rectilinear lens performs that magnification optically.

My advice is to use a fisheye lens when you want a fisheye projection, and use a rectilinear lens when you want a rectilinear projection, unless you can tolerate reduced enlargeability.

If you need high-resolution ultrawide rectilinear images and a used 25 doesn’t do it for you, the next step up from that is a digital back on a view camera with a digitally optimized view camera lens. The Cambo Actus gives you some movements, but the Actus 24mm lens is designed for 24x36 sensors. It has coverage for a 33x44 sensor, but without any movements—I see no advantage over a used 25mm DFA. The 23mm Rodenstock Digaron has more coverage, but won’t fit in front of even a small-format mirror box. It needs a real digital back.

Rodenstock 23mm f/5.6 HR Digaron-S Lens 150120 B&H Photo Video

Rick “who has been using an Arsat fisheye for nearly 20 years” Denney

Hi Rick - thks for the information....I looked at the Actus 24mm , but found a good (& fairly rare) used 25mm DFA which produces excellent images on the 645Z....however I occasionally need wider for interior and architectural shots requiring movements, and was looking for a 'distortion-free' solution...hence the Cambo Actus Mini idea....I already have the Fuji XT20, which I could use in combination with the 25mmDFA.

I did have a Hartblei 45mm t/s for the 645Z , but often found that was not wide enough for 'tight' interiors, even with movements, and the image quality was nowhere near DFA quality. (BTW - Hartblei did mention that they may be making a new version of the 645 t/s lens following their renewed co-operation with Stefan Steib/HCam (on t/s lenses for 35mm full frame cameras), I suspect using Zeiss glass rather than Ukranian glass...…)

The Rodenstock Digaron 23mm + Linhoff Technika + Hassy back (50MP and 100MP) is Sean Conboy's combination of choice for his brilliant architecture work, but also assumes you have GB£50,000+ to invest...and 30 years of camera movement experience!

Thks & Rgds, Ian

[BostonUKshooter]

Hi Rick - thks for the information....I looked at the Actus 24mm , but found a good (& fairly rare) used 25mm DFA which produces excellent images on the 645Z....however I occasionally need wider for interior and architectural shots requiring movements, and was looking for a 'distortion-free' solution...hence the Cambo Actus Mini idea....I already have the Fuji XT20, which I could use in combination with the 25mmDFA.

I did have a Hartblei 45mm t/s for the 645Z , but often found that was not wide enough for 'tight' interiors, even with movements, and the image quality was nowhere near DFA quality. (BTW - Hartblei did mention that they may be making a new version of the 645 t/s lens following their renewed co-operation with Stefan Steib/HCam (on t/s lenses for 35mm full frame cameras), I suspect using Zeiss glass rather than Ukranian glass...…)

The Rodenstock Digaron 23mm + Linhoff Technika + Hassy back (50MP and 100MP) is Sean Conboy's combination of choice for his brilliant architecture work, but also assumes you have GB£50,000+ to invest...and 30 years of camera movement experience!

Thks & Rgds, Ian

...and the new Hassy 21mm for the XCD mirrorless looks like it will impress?
….wish there was a MF equivalent for the Nikon 14-24mm....it delivered excellent images even at 14mm, although there was some small distortion in the corners....

[Sarnian]

I'd love to get a Phase One P65+ to use with my Mamiya Sekor D 28mm lens. That would give a 17mm f.o.v. with 60 megapixels!

Don't worry, I know this is the Pentax forum, so just to state that I DO own a 645Z. Perhaps I'll just settle for a secondhand D-FA 25mm rather than having two systems (I can't afford the P65+ anyway!). I'd get a wider image with the P1 + 28mm combo but would the image quality be better than a 645Z with the 25mm - especially considering how old the P65+ is? Probably not.