Sunday 11 February 2018

cheap wide options on mico43 (and how you can get more out of them)

Of course I like wide angle lenses ... what landscape photographer doesn't feel the attraction.

For many the FF equivalent 24mm lens is about the beginning of where we like our wides, perhaps 28mm. This means for micro43 that something at or less than 12mm is where we'd like to be. Today I'd like to present a bit of evaluation work I've done on my two options:

  • my trusty Panasonic 14mm f2.5 + the GWC-1 adapter
  • my recent addition, the 12-32 f3.5~5.6 zoom

In theory the P14f2.5 with the GWC-1 becomes an 11mm, so lets have a look at what a difference can be found in 1mm, and as always I'll throw in a few "curve balls" for alternative ways to look at these lenses (hint: not all m43 cameras are equal)

Method

all shots are taken with the camera on a tripod, which was not moved. The camera was not repositioned only lenses were changed and lens f-stops.

Data


First, the 12~35, exactly as it comes Out Of the Camera as a JPG (OOC JPG) at f3.5



Yes, even with Panasonic corrections we see a little vignetting ... so now, lets put the P14f2.5 & GWC-1 onto the camera...


which you can see is a little wider than the 12.

If one wants to get the best from these lenses then stopping down to f5.6 is "the right stuff" to optimize light evenness and not hit diffraction.

Both cleared up, to about equal. Here is the P14&GWC-1 @ f5.6


which you can see tidies up nicely.

So, lets look at something else which pushes these lenses to their design limits. The GH1 camera actually has a multi-aspect sensor, so when using 16:9, you can actually get more pixels (this subject covered over here). This isn't just making more pixels from the same sensor (such as the shift from 13Mpix to 16Mpix), its actually capturing a slightly bigger format. I understand a few other Panasonics have this feature too.

First lets see what more width we can get out of the 12-32mm using this strategy.


which is very close to what the P14&GWC got in 4:3 ... so lets look at that combo in 16:9 format


which is (as expected) wider again.

Of course if you aren't shooting a bunch of straight lines (like Pine Trees tend to be ) then you can perhaps get away without lens corrections (for pincushion distortion) and end up getting wider again, but of course only if you shot RAW, and wanted to process without corrections (oh, gosh, did I just mention another advantage of RAW).

So, again the 12-32



then the P14&GWC-1



So this about runs the gamut of what is the difference between 12mm and what you can get with 11mm (and if you also have a GH1 GH2 or GH5 camera) snick out a bit more when using 16:9 (which is something I do with wide landscapes anyway).

Since I do RAW mostly anyway, I'll leave you with a version which I processed on Snapseed, and tweaked up the image pincushion distortion too.



which makes for an interesting comparison, for as the 14&GWC-1 is so much wider, even in 16:9 mode it captures almost exactly the same height as the 12mm did as an OOC JPG. Thus using RAW I can overlay the capture of the 12-32mm zoom and see exactly how much more I get using my GH1 and the 14&GWC-1


... not insignificant.

One last point, lets look at the plain raw conversion, with no sharpening for corner sharpness. This is a screen grab of what I see in Photoshop at 50% (you can see which is which file in the window name):


I typically evaluate sharpness on screen because after many years of looking that's pretty much what I see when I compare it to prints done at 150DPI from the original files (which in this case are about 4368 x 2464  Pixels which is good for a print of about 74.0 x 41.7 cm or 29.12 x 16.43 inches)

So have a think about it and see what you think. In my view the combination of GH1, P14f2.5 , GWC-1 and RAW on Snapseed is a winner ... especially with old gear like this :-)

2 comments:

CM said...

Fascinating results, I am certainly going to try the RAW trick with the 12-32 and compare it to my UWA combo, the zoom with a Ricoh dw6 converter making it a much wider 9.5mm. Using the Raw thing might make the combo photos even wider (if acceptable). Using the converter lacks distortion correction so may as well try the combo full width.

obakesan said...

Hi CM

just make sure your camera has the multi aspect sensor as does the GH1 ... or you won't get these results :-)