Jim Schemel wrote:
Zeiss Makro Planar on 5D.If any one knows what you call the plant that would be great
-Jim
Wow, that's a really nice shot. I like the blues.
lacksative wrote:
About mechanical vignetting again
5Dii + 85L
Any consensus on what causes it? My only guess is that the rear element is really large and that there's a rectangular area surrounding the sensor, which prevents a full circle from forming.
kakomu wrote:
Any consensus on what causes it? My only guess is that the rear element is really large and that there's a rectangular area surrounding the sensor, which prevents a full circle from forming.
Correct. It is because the mirror box obstructs some light rays exiting the lens.
Note there are two effects here. First, the "football" shape of off-axis out of focus highlights is due to the geometry of the scene relative to the lens; the front element appears oval when viewed from an angle. This effect is visible even in lenses that have a smaller maximum aperture, but disappears as the focal length becomes long. This is because the narrower the angle of view, the only light rays that reach the image plane are those that are nearly parallel to the optical axis (and therefore they "see" the front element as nearly circular).
The secondary effect, which is a "clipping" of this football shape in very wide aperture lenses, is due to the aforementioned mirror box.
A bunch of Thank you's go out to Kent, philber, sebboh, Ulrikf, Yakim and Jos. I hope I haven't missed anybody. It feels good knowing that Indexing the images isn't a work in vacuum.
Here is what I think about it all.
I have no way to evaluate the point with the indexing. There are however some hints given at the forum. The reading counter ticks on. This tells me there is some interest for the thread. There are from time to time some commenting the Index, as above, and it happens I see posts in other threads referring to the "Admirable" thread when lenses are discussed.
I don't see the length of the Index posts as a problem. There is a blabbering limiter at the forum prohibiting posts weighting more than 60k. The three Index posts aren't really maxed out so the total weight is well under than 180k. That is less than most images posted at on-line forums. Sometimes I have been thinking of moving the Index to my own website to make it look nicer. Now some sections are in a mess, for example the Zeiss and Zenith lenses. But, I'm a bit lazy and it works as it is.
How long can this go on? I don't know. I update the Index, my local copy that is, from time to time. I get a good look at the images and if I don't forget about it it doesn't take a lot of time. As long as people are posting images and the reading counter moves I see no reason to ask people stop.
Jos: If you would like to sort of get in charge for this thread, rather than starting a new one, please be my guest. Just send me a PM.
This thread is a great resource, Jonas, as everyone's said, thanks for starting it and taking the time to keep the index updated.
I had thought about PMing you a while back about moving a version to a website as a database with a much more appropriate user interface, but since we all own our respective images it would be a huge headache. As it sits it is just fine, IMO, and I'll keep clicking in as long as it keeps going (even for the minimum focused close-ups and completely OoF frames )
Makten - I'm liking that shot. Perhaps because Basil is my favourite herb... i dunno. but that pic is fantastic
*pondering saving it to desktop for wallpaper*
And Twok - Some weird highlights in that shot. How did that work?
Jos Tesseract wrote:
Makten - I'm liking that shot. Perhaps because Basil is my favourite herb... i dunno. but that pic is fantastic
*pondering saving it to desktop for wallpaper*
Thanks! I'm having an experiment trying to keep the little fellow alive in my kitchen for as long as possible. It has only been a couple of days yet.
The Nokton is lovely in my opinion. I had to recalibrate the rangefinder myself to make the lens usable wide open, since the focus shift is so severe that they obviously calibrated the lens for accurate focus at f/2.8. But using f/2.8 in the middle of the winter in Sweden is hardly even possible.
)
