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arthurking83
07-10-2011, 10:44am
The folks at LensRentals.com have been busy playing with multiple new toys and the 'head honcho' over there seems to have put together a well written article on how all these ... my lens is soft or my camera is back focusing stuff can be confusing and badly responded too.

Lensrental article by Roger Cicala (http://www.lensrentals.com/blog/2011/10/notes-on-lens-and-camera-variation)

Makes for an interesting read if you are interested in this kind of stuff which, BTW, I think is important to understand.

I also agree with him on his summary of Live View, and even though I don't use it 'all the time' but I use it regularly .. I think it's one of the most impressive and important breakthroughs in DSLR camera bodies, ever! .. well for now. EVF's are the next logical step beyond that, and even tho we scoff at them because they're currently not as high quality as an optical vf, but when the technology reaches maturity it'll kill the OVF and dance on it's grave at it's funeral :p Focusing will be more accurate and consistent (or at least should be) as it is with Lv mode at the moment.

Anyhow, if your camera/lens is not producing the goods as per 'it's reputation' implies it should be, then keep this article in mind.
And knee jerk reactions to a pseudo problem, may actually be doing more harm than good to the overall system.

swifty
07-10-2011, 11:18am
Good article. Thanks for the heads up.

OT: it's more or less inevitable that EVF will surpass OVF in all technical ways. But much like records, film etc. Some ppl will always prefer the feel, or in this case the 'look' of OVFs.
Looking through a Contax 645 VF was an eye-opener for me (pun-intended). Not that it was perceivably brighter than FF VFs or anything but the depth perception and 'feel' was just something else.
Btw I welcome evfs and can't wait to see megapixel monster EVFs to appear on FF cameras with all sorts of overlays and focus aids that can be switched on at a touch eg. Peaking, 100% magnification etc.

arthurking83
07-10-2011, 11:44am
I think for me, one of a possible technical aspects of an EVF over an OVF is a real time DOF preview system.

With an optical system, you're limited by the contrast ability of the matte focusing screen.
With an EVF, this matte focusing screen is completely eliminated and focusing and previewing DOF becomes a native part of the viewfinder.. and not some fixed intermediary overlay between your eye and the lens.

The reason I mention this, is that with the D300(at least that I know of due to experience), is that if you're in Lv mode AND if you have a non CPU lens fitted, the aperture changes in real time as you change the setting on the aperture ring.
That is, it's not simply held wide open, as is the case with a CPU'ed lens.
DOF preview is not the same. With DOFP, you have to set your aperture value and then press the DOFP button to see the apparent DOF, but this usually means a massively darkened image, so the end result is not really a DOF preview.. but more of a very dark viewfinder experience lots of squinting.
The difference (mainly for bokeh junkies) is that the comparison of OOF renderings between each aperture value is more immediate and therefore easier to quantify relative to each other.

I can understand the uberness of the Contax vf, and it's probably the same as that of a Hassleblad or a Rollei TLR(that I've experienced) ... and there is also a better vf experience in switching from a standard Nikon screen to a Katzeye screen on my D300 too. Maybe not as much, but the difference is still quite noticeable. DOF is shallower and focus snap is more pronounced.

If all of this technical gibberish translates in to a better performing camera body.. then I think we are probably better off in most ways.
Nostalgia is never lost on me, and in many ways I love it as much as I do the future of technical progress(but not records and CD's and valves and stuff like that tho).
But I get the feeling that in order to progress forward we have to completely eliminate some of our old ways and look at how the new ways can be used to help us move in this forward direction.. especially with tech such as EVFs and so forth.

swifty
07-10-2011, 12:03pm
I completely agree. With the passing of one of the greatest innovators of our time yesterday, it's poignant he'd previously spoken of death and how it's the best agent for change, allowing the new to supersede the old (paraphrasing).
Maybe we 'have' to let the OVF die for us to truly embrace what EVFs can do.
Btw, quick question: what happens when you're in LV and you press the DOFP button? I don't use LV often and don't have a camera in front of me to check.
Is it like having manual aperture rings and the DOF is rendered in real time whilst the display compensates for the darkening?

jjphoto
07-10-2011, 6:06pm
That's a fantastic article and worth reading if you are a pixel peeper.

I actually swapped from a 1ds2 to a 5d2 (which I feel is an inferior camera in many respects) simply because the 5d2 has Live View and the 1ds2 doesn't. Live View is a very important feature for certain types of photography where an optical viewfinder, even a good one such as on the 1ds2, simply can't cut it. Having said that, optical view finders are much easier to use for many types of photography and Live View is really only practical when a camera is on a tripod.


....
Btw, quick question: what happens when you're in LV and you press the DOFP button? I don't use LV often and don't have a camera in front of me to check.
Is it like having manual aperture rings and the DOF is rendered in real time whilst the display compensates for the darkening?

Yes, at least with a 5d2.

arthurking83
08-10-2011, 11:50pm
.....
Btw, quick question: what happens when you're in LV and you press the DOFP button? I don't use LV often and don't have a camera in front of me to check.
.....

On a D300 .... nothing!
No matter if you're using a CPU'ed lens or not, the DOFP button doesn't' operate when in Lv mode(at least on a D300).
But the weird part is that when a non CPU lens is mounted the aperture works in real time.

For a quick tech aspect as to how something like this can be important:
Shooting the moon late at night.

Manual lens, focusing via OVF .. images are not as sharp as they should be.
Switch to Lv mode.. lens mounted is a manual lens. Due to the massive darkness surrounding the moon, Lv doesn't work all too well, because the moon has no detail contrast at all. It's just a big white round blob, slowly creeping across the screen. Mount a high quality modern CPU'ed lens and you still get the same thing.. big white mess of round blob. Manually focusing on the detail of the moon is technically impossible.
You can focus to the edge of the moon where the horizon meets the darkness of space I suppose, but I want to see the detail in the craters.
Mount a manual lens with a aperture ring(my 500 is fixed at f/8) and in general the lens is kept pretty much open.. even at f/8 or so. But stopping down the lens to f/32, maybe even f/45, reveals a trick. It's a dark trick, but it instantly reveals the details in the moon, on the review screen. Focusing is now made easy as you can zoom in to 1:1 detail.
Some folks recommend to focus at or close to infinity when shooting the moon, and this method is very hit and miss. There is an exact point, where focus is best.

Setting the D300 to control the aperture via the aperture ring(control settings), doesn't help either, where you'd expect the aperture to work when in Lv mode. if you set the camera up with aperture ring control, you lose Lv mode.. simply doesn't work. From memory, I think the D3 series does tho, so it may have real time aperture control in Lv mode.

If a modern lens is required to capture the image, the simple trick of taping the CPU contacts up before mounting the lens to the camera helps.

How this can be of help(to an EVF) is that we all know that stopping a lens down helps to achieve better contrast in the image(afterall, the Lv view is for all intents, a view of what the sensor is going to capture anyhow! ;)) .. and we know that an EVF is not going to allow as good a dynamic range as will an OVF.. so with a bit of quick operating camera histrionics via electronics, maybe the EVF is already capable of producing a better quality vf experience.

I'm keen to try out one of the new A77 Sony SLT cameras, one day, just to see where current EVFs stand in terms of quality.