28mm on a 180

[PSon]

I guess the only way to personally solve this problem yourself is to have a second digital back that would work with these ultra wide lens. If you don't have a second digital back, it makes you appreciate the 40mm even more.

 

[f8orbust]

I found the test I made a few years back...

Since your testing was done in June 2011, you won't have had access to the 28 XL's custom CF (released around March 2012) ?

The CF can make a significant difference on a back like the 180, though shifting will still be limited. That said, so it is with the R/S 28, since it only has a 70mm IC with a hard vignette.

Would be interesting to see the test done again with the CF and C1 v8.

(OT: Darlene ('Darr') uses the 28 with a CFV-50c - it would be interesting to hear how she is getting along with it since the new CMOS sensor is reported to be 'difficult' with symmetrical WA lenses).

Jim

 

[archivue]

32 and 40 aren't that close !

Don't forget that the IQ180 sensor is quite large... i have a 35xl and a 45 with a 36x48 sensor, really different angles of view !

 

[Richard Osbourne]

I've got a Cambo and IQ260. I originally bought the SK 28 after reading guy's review. Unfortunately, with 10mm of shift, certain scenes had uncorrectable colour casts, and the (huge) centre filter caused quite a bit of ghosting, even in only lightly backlit scenes - again, uncorrectable.

So, I ended up swapping for the 28 HR on a T/S base. It's a far sharper lens BUT there is more distortion, which is clearly visible on architectural scenes and I don't use more than 5mm shift as the hard vignette appears in the corners. I use LCC on all images - the back doesn't show it, but there is colour cast visible when you open the files up in C1.

I don't use the centre filter on the 28 HR, though I do have it. I haven't found it a problem. LCC seems to correct it easily and I quite like a little vignetting in some images.

I would dearly like a 28mm lens with at least 10mm shift but these are the two choices. Overall, the 28 HR is a stunning lens, especially used at F8, with a little tilt - startling front to back sharpness right across the frame.

The above is for an IQ260. I would imagine the problems will be the same or worse for a 180. I couldn't recommend the SK28 for it.

Had I realised the above, I would have bought the 32 HR, even though it's got a narrower FOV. It has less distortion and over 10mm of shift so somewhat making up for being less wide.

I'm doing research on how well a Schneider 28mm will perform using a Cambo WRS and IQ180 combo.

I read Guys comparison write-up between the HR & SK that was several years ago and back then it appears the SK might not have been well suited on the 180. But things change; such as C1.

So the question is - will a SK 28 work well on a 180 using a WRS. How much movement is there? (I'm not expecting much if any) What are the issues and are they correctable in C1. I'd also expect the CF is a must.

If the SK is a bust I'll have to rethink the HR but I'd like to hear from those who have actual experience.

Don

 

[Richard Osbourne]

I should add that the 28 HR handles flare reasonably well - big orange blob opposite the light source in worst case but can easily be dealt with by masking the sun and combining files in PS. If you have the sun in the frame (which I include in a lot of my work), there can be bad ghosting - but no worse than most W/A lenses. Certainly better than the Phase 28 lens.

 

[Paul2660]

Wonderful lens, and if it came with a 90mm IC, well, enough said.

There are some unique optical issues besides flare that will sometimes occur, in the attached image, I have shown the main ones. Note these are all when you shift the lens, on center none of this shows up. I numbered the areas of the image to try and make it clear.

1. Is a strange ghosting, that seems to happen with my lens on shifts much past 3mm, if I have a situation where I am working with gaining light on the side of the shift. It's a lighted curve that matches the curve of the IC but starts within 2mm of shift.

2. This is what I believe is penumbra of the IC, On the 28 HR you will almost always see it if you see the hard edge of the IC. This can really only effect the topmost part of the shift. This image I shifted to 7mm or so. 5mm and you will not see the black hard vignette.

3. This is the mark left by the IC indicator installed by Rodenstock (never have figured that one out). It creates all kinds of weird issues and you will not be able to correct it with the LCC. Sometimes depending on the file, content aware can remove it. As you can see on a 7mm shift, it's not too much of the overall image. It's also very easy to crop into the overall stitched image to get more of panorama.

I have tried shifting without the CF on and sometimes the strange ghosting of the IC edge doesn't show up, but the other issues still happen.

This shot was taken with the CF installed and a thin CL-PL on the CF.

My 28HR with 1/2 of a degree of tilt will most often have a hyperfocal distance in the range of 8 feet to infinity @ f8 +1 (copal talk) aperture.

Paul

 

[Paul2660]

This is the full shot, taken last fall, IQ260, 7mm of shift left and Right, 28HR F11. I am a lover of the vast hyperfocal range of this lens. I always make 3 full shifts, as the light may change so fast that I may just run with L and R or use all three, and or create the shot and pull in pieces that help create the look I wanted to start with. These were taken a 1/4 to 1 sec of exposure at iso50, thus a bit of movement in the leaves as it was not dead calm, however the detail is still there.


As usual the sRGB conversion has killed my sky a bit, but the effect is still there.

Paul