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Shift Lenses on u4/3rds

jmooney

New member
Hi All,

I love my G2 but the one thing that I haven't quite nailed down yet is a lens with some perspective controls. Is anyone working with one? If so how's it going? Due to being able to adapter basically any lens in the world to a G2 I'm sure there are plenty of options but I can't really find much out there by anyone with some experience.

I'm looking to use it for architecture and landscape, I'm not really into the latest craze of using them to make everything look like a model railroad layout :poke:

Any info or advice is much appreciated.

Jim
 

pellicle

New member
Hi

shift lenses are (perhaps) moot on 4/3 because:

-stitching and pano software gives you extra pixels and perspective corrections needed in the majority of architecture situations
-few lenses which are wide enough (to require perspective correction) have sufficient coverage or optical quality on the edges to be reasonable candidates.

but reading:

I'm not really into the latest craze of using them to make everything look like a model railroad layout :poke:
I'm wondering if you're referring to tilt lenses (which can be used to provide that effect) and that is an altogether different kettle of fish.

I use a 90mm lens for wide angle on my LF camera and so tilt and shift are needed to (in order) perspective and focus plane control (for example)



however 4/3 seldom provides situations (because of its small size of capture area) that focal planes need to be (or can be) controlled in this way with wide angle lenses.

I am currently waiting for a tilt lens on my 4/3 camera however so that I can try my hand at some things which do need tilt (aside from the model railway look which I don't like either)

Perhaps this may be interesting reading:
http://cjeastwd.blogspot.com/2010/02/control-over-focus.html
 

dick

New member
Hi

shift lenses are (perhaps) moot on 4/3 because:

-stitching and pano software gives you extra pixels and perspective corrections needed in the majority of architecture situations
-few lenses which are wide enough (to require perspective correction) have sufficient coverage or optical quality on the edges to be reasonable candidates.
If you shift and stitch instead of panning and stitching you avoid loosing res by (un)distorting your image.

All 35mm film lenses have enough image circle for shift on m4/3 (and MF too).

Some of do want to shift long lenses and "get it right" ... but the benefits are not so apparent.
 

Diane B

New member
Fotodiox makes a shift adapter for MFT but from what I've read most aren't happy with it. I've used shift with my EF 45/2.8 but firstly the FOV is 90mm and secondly working with EOS lenses is a pain---and third is that I don't find a real need to do this with MFT for stitching and didn't use shift that often to correct distortion. If shift is needed often MFT may not be the system at present that would suit.
 

pellicle

New member
Hi

If you shift and stitch instead of panning and stitching you avoid loosing res by (un)distorting your image.
true, but then if you pan and stitch instead of just shifting you gain much more resolution and you avoid getting out of the sweet spot of the lens. All of the lenses I have which can be shifted are much sweeter in the center than at the edges.

If you were to shift and stich it would create more pixles, would remove the need to perspective correct but will get you out of the sweet spot of the lens and because you are magnifying the image more (4000 pixels out of the entire width of 35mm frame is less magnification than 4000 pixels out of one half of its width) by using the 4/3 format then you will observe the limits of the lens more.

All 35mm film lenses have enough image circle for shift on m4/3 (and MF too).
and of course the vast majority of wide lenses suck at the edges. On 4/3 the lenses which equate to a 24mm (on 35mm or a 90mm on 4x5) are those with focal lengths below 14mm now, can you name me many of those which are sharp on the edges, not stratospheric in price and of a mount which there are any supported shift adaptors?


Some of do want to shift long lenses and "get it right" ... but the benefits are not so apparent.
shifting long lenses will produce minimal distortion correction effects. The angle of view changes less and the coverage is insufficient. The effects and benefits of shift are more significant on wider lenses and I would argue (and I would say that I own and operate such equipment) that while the lord giveth with the hand of extra coverage he taketh away with the loss of lens sharpness at the edges.

So I reckon that putting a 28mm on a 4/3 camera, taking an array of overlapping shots then perspective correcting that will offer a better image than if you put a 28mm shift lens onto the camera and did the same.

More so with a 24mm

Further if you put a 50mm lens on and stitch the same image you'll have so many megapixels to play with you'll have essentially no losses worth mentioning in the correction

so there is the theory and then there is the application of the theory

my 90mm lens on my 4x5 sucks when it comes to reading the LP/MM specs of resolution compared to my 24mm lens on 35mm. The thing is however you need to magnify more to make the print with the 35mm, and so ...

some interesting reading for you:
http://cjeastwd.blogspot.com/2009/02/lens-tests-whats-missing.html

so perhaps your assumption on "some of us want to get it right" was a wee bit unfounded (when it comes to me at least)
 

dick

New member
Hi
if you pan and stitch instead of just shifting you gain much more resolution and you avoid getting out of the sweet spot of the lens. All of the lenses I have which can be shifted are much sweeter in the center than at the edges.
Bernard would agree with you... but it does help if you have quality lenses.
So I reckon that putting a 28mm on a 4/3 camera, taking an array of overlapping shots then perspective correcting that will offer a better image than if you put a 28mm shift lens onto the camera and did the same.
If you have a lens that covers more than m4/3, it would make sense to use it on a bigger camera (especially for moving subjects) but I do not have a D3X yet. I do appreciate that pan-and-stitch is a useful technique in some situations - and I intend to get a p&s head soon. For very wide shots (or curved subjects) no lens would work in shift-and-stitch mode.
Further if you put a 50mm lens on and stitch the same image you'll have so many megapixels to play with you'll have essentially no losses worth mentioning in the correction
The quality of the pixels counts as well as the number... and I expect that my 300mm lens on my Hasselblad H4D-60 will produce more detail than my Novoflex 640mm lens on the GH2 I expect to order this week... but the 200mm Nikkor with the GH2 might be useful for pan-and-stitch when I am traveling light.

The Hasselblad has no AA filter, but the image is Bayer interpolated, so, if and when I get the 86H multi-shot to use with my Apo-Digitars, the quality per megabyte would be even better.
my 90mm lens on my 4x5 sucks when it comes to reading the LP/MM specs of resolution compared to my 24mm lens on 35mm. The thing is however you need to magnify more to make the print with the 35mm, and so ...
I also have a selection of lenses for 5 * 4 and larger, and I do appreciate this... but I think that my Novoflex 400mm has ample coverage for a 40 * 50 mm sensor (or m4/3) and this is, I believe, a Leica made lens which will be useful on digital, and I hope it will produce a better result than an uprezed shot taken with an Apo-Digitar 210. I would not expect my 480mm LF lens to to be anywhere near close. I could shift-and stitch with the 480 to get the same angle of view as the 210, but why bother?
so perhaps your assumption on "some of us want to get it right" was a wee bit unfounded (when it comes to me at least)
Please do not bother to explain what you are trying to say here...
I appreciate being able to "get it right" by using the full range of movements of my Sinar P, P2 and P3 on all my Schneider Apo-Digitar and large Format film lenses without having to buy T/S adapters for each... and avoid having to lose res by distorting my images, and would like to have a T/S adapter for m4/3 so that I can do the same with all my Nikon mount lenses.
This is trying to say that standard lens tests are not applicable to real world scenery photography?

Most of the scenery I photography includes buildings, so I asses lenses by photographing brickwork at 500m or more... a Wide Angle lens that can resolve brickwork at 500m is OK for village and harbour work... but (particularly with a curved "amphitheater" harbour) pan-and-stitch with an inferior system and a longer lens can produce adequate resolution... as long as the scene does not include large areas of moving trees or vehicles or waves.
 
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pellicle

New member
of this link: http://cjeastwd.blogspot.com/2009/02/lens-tests-whats-missing.html

This is trying to say that standard lens tests are not applicable to real world scenery photography?
not quite, it was trying to identify that lens test charts testing the resolving power of the lens confuse people because they often omit factoring in the working distance that lens tests are conducted at (how often do you take pictures of things at 1.2 meters with a wide angle lens) and that large formats which have lenses which test to "lower numbers" may actually resolve more details of real world subjects because you are likely to use them at something closer to the test working distance and print magnification is less as well.

sorry about going :OT: with that one

I appreciate being able to "get it right" by using the full range of movements of my Sinar P, P2 and P3 on all my Schneider Apo-Digitar and large Format film lenses without having to buy T/S adapters for each... and avoid having to lose res by distorting my images, and would like to have a T/S adapter for m4/3 so that I can do the same with all my Nikon mount lenses.
which brings me back to my point that the movements are needed on the 4x5 (never heard of a TS adaptor for a lens on a Sinar) to control focus with tilt as anything else and that for the smaller format of 4/3 that isn't quite as common a need (but closeup product shot photography does come to mind) and that using shift and stitch from older lenses which are designed to cover more (like 35mm or MF) on 4/3 is no more "get it right" than simply rotating the camera and stitching. I supported that with:
* shifting at longer focal lengths will be less aparent in effect
* shifting wide lenses (like 8mm) will often get them out of their center and the edges are grubby thus making for a lower quality image
* I can't think of any lenses which are wide on 4/3 which you can adapt from 35mm (or anywhere) which could shift and get any better result than using a dedicated 4/3 lens and pan-stitching over shift-stitching.

I can only think of the Voigtlander 12mm which has the potential coverage, but isn't really amenable to shifting. So do you care to suggest one?
 
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dick

New member
of this link: http://cjeastwd.blogspot.com/2009/02/lens-tests-whats-missing.html



not quite, it was trying to identify that lens test charts testing the resolving power of the lens confuse people because they often omit factoring in the working distance that lens tests are conducted at (how often do you take pictures of things at 1.2 meters with a wide angle lens)
sorry about going :OT: with that one
I agree that the working distance for which lenses are optimized is a significant but largely ignored factor... some lenses described as "macro" lenses (like the Macro-Planar 120) are optimized for 1:1 to infinity... so they are at the edge of their range at 1:1, and will not perform nearly as well at 1:1 as a lens optimized for 1:3 to 3:1... but they perform very well at "table top" distances between 1 and 2 meters.
 

dick

New member
...using shift and stitch from older lenses which are designed to cover more (like 35mm or MF) on 4/3 is no more "get it right" than simply rotating the camera and stitching.
I appreciate that you are an advocate of the pan-and-stitch technique, you do not seem to be aware how much res you can lose through distorting an image to correct perspective.

I appreciate that the benefits of shifting lenses on u4/3 is mostly for perspective control rather than shift-and-stitch, and that pan-and stitch can be a useful technique to increase pixel count - and res.
 

pellicle

New member
Hi

I appreciate that you are an advocate of the pan-and-stitch technique, you do not seem to be aware how much res you can lose through distorting an image to correct perspective.
I have come from distorting optically to distorting digitally. I have explained why I made the change and even provided some examples on why. I'd appreciate it if you could justify your position at all (as I have justified mine). To this point however, it seems that I explain my position my reasoning and offer some evidence and you just state you position with the "do it right" mantra and perhaps a touch of aloof smugness to cement that you're doing it right and I'm doing it in an inferior manner.

I asked you to name a single lens which would be suitable but you have so far mentioned none. Or explain why it is that shifting and stitching will not result in equal or perhaps exaggerated deterioration of the image due to the losses in resolution caused by doing that.

I have discussed this openly as I often find that mis-conceptions fill forum like this with people saying things un-substantiated and un-substantiatable in what is supposed to be a place where people exchange ideas and learn about photography. The artisan aspects of photography are not (to me, though I appreciate it is for others) a religion based on belief systems, that is perhaps for the aesthetic of composition and expression.

Your position seems to be one of expressing some notion of "do it right" and then remain silent on why or how.

but either way I don't mind and I don't have any reason to wish to see you change what you do or accept anything I say. As mentioned I do use shifting on other formats and would have also appreciated a shift lens for wide on my 4/3 format cameras, if such an adaptor exists or if such a lens to make use of it exists, for the situations where stitching is impracticable.
 

dick

New member
Hi
I have come from distorting optically to distorting digitally.
Optical distorting does not involve digital re-sampling, so the degradation of the image is not so marked... and you can use acutance developing to sharpen as you remaster using film... see the examples in Merklinger's "The ins and outs of Focus"
I have explained why I made the change and even provided some examples on why. ...you're doing it right and I'm doing it in an inferior manner.
¿You think that an increased pixel count is justification? Please make no further attempt to explain. I hope and expect that there are people here that see the logic in what I write.
I asked you to name a single lens which would be suitable but you have so far mentioned none. Or explain why it is that shifting and stitching will not result in equal or perhaps exaggerated deterioration of the image due to the losses in resolution caused by doing that.
I stated that any FF 35mm format lens will have ample image circle for stitching on micro- 4/3. I have no interest in stitching for wide angle on micro 4/3, but, as I do not have a full-frame DSLR, I could use my Nikkor WA (I think it is a 28mm) with a shift adapter to get FF 28mm angle of view... but this is irrelevant, as I want shift mainly for perspective correction.
I do use shifting on other formats and would have also appreciated a shift lens for wide on my 4/3 format cameras, if such an adaptor exists or if such a lens to make use of it exists, for the situations where stitching is impracticable.
So what is the problem?

If you use a low-res or no res camera, with and AA filter, you will not notice loosing the res you never had... but if you want proof that re-sampling can seriously affect resolution:

See the attached screen grab below...

If you suck this into Photoshop, at 66.6% you get a very pronounced interference pattern in the material... this is more visible on the Eizo, but also clearly visible on the Mac Book Pro. ...but at 100% you can clearly see every stitch! Between 66% and 100% you mostly just lose resolution.

I think that this is a good illustration of how digital "features" like any-ratio scaling and distortion can really screw up you image!
 

pellicle

New member
well first you say:
You think that an increased pixel count is justification? Please make no further attempt to explain.
then you say:
So what is the problem?
so I hesitate to answer

then you show moire issues which are unrelated to the problem discussed and more or less just demonstrate you have issues with understanding how to rescale images in Photoshop without effecting texture.

I think that this is a good illustration of how digital "features" like any-ratio scaling and distortion can really screw up you image!
no further comment
 

Brian S

New member
The shift adapters are cheap compared to what my PC-Nikkor 35/2.8 cost, if you have legacy lenses designed for full coverage of a 35mm frame it is certainly worth experimenting with for yourself. As for a lens wide-enough to be used for perspective control, you can find some 16~17mm legacy lenses out there- but likely to be relatively costly. 20mm is typically the breaking point for wide-angle lenses to start jumping on cost. So it depends on what field of view you require for the work.
 

dick

New member
The shift adapters are cheap compared to what my PC-Nikkor 35/2.8 cost, if you have legacy lenses designed for full coverage of a 35mm frame it is certainly worth experimenting with for yourself. As for a lens wide-enough to be used for perspective control...
Are there any shift adapter that can be used with Nikkor lenses on micro 4/3?

Given the hardware, it is worth controlling the perspective with any length of lens.
 

pellicle

New member
Hi Brian

The shift adapters are cheap compared to what my PC-Nikkor 35/2.8 cost,
the PC-Nikkor will of course project an image circle to cover a much larger area than a regular 35mm f2.8 for 35mm film.

I found a fellow who is doing shift stiching on his GF-1 and blogging about the fotodiox adapter here

He suggests that with shifting the camera (important point, not shifting the lens) he takes 3 images in portrait and stitches into a single landscape (same method I use on my G1). He then gets about 33x18mm of sensor capture and so quite reasonably makes a comparison with his 5DMkII. He makes an interesting point on this:
The stitch is of slightly more letterbox proportions, but an aspect ratio that I happen to like and it also yields a lot of pixels too, the 5D a 120mB versus the GF1 171mB file size.
He seems to like his OM28mm lens to work with, so we're not actually considering ultra wide here.

I particularly recommend viewing both images in the center of your screen and carefully switching between the two to see exactly what is different between the two.

the difference between the DoF of the 28mm lens at f8 and his zoom (set about the same) is interesting..

He makes an interesting point in a comment:
On the other hand, for the majority of my requirements, the quality I get from my GF1 WITHOUT stitching is perfectly adequate. I should guard myself from getting too sucked into developing methods and equipment rather than getting out there and making images. Equipment can be far too seductive if you let it!
 
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