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Archive 2013Sony a7/a7r limited by E-Mount?
p.2 #1Sony a7/a7r limited by E-Mount?
theSuede wrote:
Me too, just saying...
To get rid of it completely (even at F1.4) the E-mount would have to about 7-10mm larger in diameter to make a symmetrical 70-85mm lens possible without any mechanical shading in the mount throat. 35mm f/1.4 is no problem, but then you get into corner angle problems in stead.
Will I see similar bokeh problems with my SLR Pentax A* 85 1.4, which is a Gaussian design, when used on a 7r?
http://dl.dropboxusercontent.com/u/5540407/85f1.4-i.gif
Edit. Looks like theSuede has opened up a big can of worms!
sebboh wrote
sure bugs me.To get rid of it completely (even at F1.4) the E-mount would have to about 7-10mm larger in diameter to make a symmetrical 70-85mm lens possible without any mechanical shading in the mount throat. 35mm f/1.4 is no problem, but then you get into corner angle problems in stead.
Will I see similar bokeh problems with my SLR Pentax A* 85 1.4, which is a Gaussian design, when used on a 7r?
http://dl.dropboxusercontent.com/u/5540407/85f1.4-i.gif
Edit. Looks like theSuede has opened up a big can of worms!
Oct 20, 2013 at 10:06 PM
p.2 #2Sony a7/a7r limited by E-Mount?
LightShow wrote:
And me.
The Canon RF 50/0.95 has a relatively small rear element and mount.
I love this pic, so obsurd.
http://www.uxcrew.com/wp-content/uploads/2009/11/3674631408_dbb16dd3b8.jpg
(Not my pics, from google omg search)
that is the most awesome combo i've ever seen! clearly the precursor of of sony's lensor controlled by a smart phone.
And me.
The Canon RF 50/0.95 has a relatively small rear element and mount.
I love this pic, so obsurd.
http://www.uxcrew.com/wp-content/uploads/2009/11/3674631408_dbb16dd3b8.jpg
(Not my pics, from google omg search)
that is the most awesome combo i've ever seen! clearly the precursor of of sony's lensor controlled by a smart phone.
Oct 20, 2013 at 10:11 PM
p.2 #3Sony a7/a7r limited by E-Mount?
Thank you for the thorough explanation, Joakim. That 85L shot is very disturbing, but I think it only happens under a specific condition (tight frame with lots of highlight bokeh). I have shot my 85/1.2 on the A99 (smaller throat than Canon) for a while now but I rarely encounter this problem.
Oct 20, 2013 at 10:12 PM
p.2 #4Sony a7/a7r limited by E-Mount?
theSuede wrote:
No, it's not a misunderstanding. F1.4 at 35-40mm exit pupil distance creates an outer angle of >40degrees. F1.4 at 28mm exit pupil distance gives more than 50 degrees. It seems the A7 sensor gets into trouble at about 25 degrees...
Either we are talking about different things, or you misunderstood ("far back" meant closer to the sensor). I was talking about shading by the mount. How on earth could that be worse if you place the exit pupil closer to the sensor? The angle gets worse, but that's something else.
No, it's not a misunderstanding. F1.4 at 35-40mm exit pupil distance creates an outer angle of >40degrees. F1.4 at 28mm exit pupil distance gives more than 50 degrees. It seems the A7 sensor gets into trouble at about 25 degrees...
Either we are talking about different things, or you misunderstood ("far back" meant closer to the sensor). I was talking about shading by the mount. How on earth could that be worse if you place the exit pupil closer to the sensor? The angle gets worse, but that's something else.
Oct 21, 2013 at 12:29 AM
p.2 #5Sony a7/a7r limited by E-Mount?
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?
Oct 21, 2013 at 08:06 AM
p.2 #6Sony a7/a7r limited by E-Mount?
Tariq Gibran wrote:
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?
Tariq, I think this one would be similar to Roger's article on the use of adapter. Yes, the problem is there. But it will only happen in rare occasion. I mean Leica (narrower throat than E) users has been happy with the fast lenses without complain about cut off. Even the widest SLR mount Canon still has problem.
Sony is going to release their 4K DSLR camera out soon with the FZ mount, much bigger throat size and almost as shallow as the E.
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?
Tariq, I think this one would be similar to Roger's article on the use of adapter. Yes, the problem is there. But it will only happen in rare occasion. I mean Leica (narrower throat than E) users has been happy with the fast lenses without complain about cut off. Even the widest SLR mount Canon still has problem.
Sony is going to release their 4K DSLR camera out soon with the FZ mount, much bigger throat size and almost as shallow as the E.
Oct 21, 2013 at 08:57 AM
p.2 #7Sony a7/a7r limited by E-Mount?
Tariq Gibran wrote:
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?
Why would the SLR lens projection be any different (once adapted) on the A7R than on a native mount. The distance to the film plane will be the same (by virtue of the adapter) and the area covered by the projection will be the same @ FF. If it plays well on a current DLSR, it should play well (or better) on the A7R as the angles of the projection will be the same. The primary diff will be that the offset sensor of the A7R will impart less refraction @ the micro-lens to the sensor ... should be a good thing (in theory).
Imo, changing the sensor that the projected image falls onto is akin to changing the paper that an enlarger projects onto. The projected image from the lens hasn't changed at all ... only the response to the projection @ tooth / sensitivity / structure of the paper is what makes the diff. The A7R is going to have a different tooth (offset sensor) in its ability to capture the energy coming from the projected image.
Edited on Oct 21, 2013 at 09:17 AM · View previous versions
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?
Why would the SLR lens projection be any different (once adapted) on the A7R than on a native mount. The distance to the film plane will be the same (by virtue of the adapter) and the area covered by the projection will be the same @ FF. If it plays well on a current DLSR, it should play well (or better) on the A7R as the angles of the projection will be the same. The primary diff will be that the offset sensor of the A7R will impart less refraction @ the micro-lens to the sensor ... should be a good thing (in theory).
Imo, changing the sensor that the projected image falls onto is akin to changing the paper that an enlarger projects onto. The projected image from the lens hasn't changed at all ... only the response to the projection @ tooth / sensitivity / structure of the paper is what makes the diff. The A7R is going to have a different tooth (offset sensor) in its ability to capture the energy coming from the projected image.
Edited on Oct 21, 2013 at 09:17 AM · View previous versions
Oct 21, 2013 at 09:05 AM
p.2 #8Sony a7/a7r limited by E-Mount?
sebboh wrote:
sure bugs me.
[Flame shield activate]
I'm probably the only photographer that likes the chopped bokeh look.
sure bugs me.
[Flame shield activate]
I'm probably the only photographer that likes the chopped bokeh look.
Oct 21, 2013 at 09:06 AM
p.2 #9Sony a7/a7r limited by E-Mount?
RustyBug wrote:
Why would the SLR lens projection be any different (once adapted) on the A7R than on a native mount. The distance to the film plane will be the same (by virtue of the adapter) and area covered by the projection will be the same @ FF. If it plays well on a current DLSR, it should play well (or better) on the A7R as the angles of the projection will be the same. The primary diff will be that the offset sensor of the A7R will impart less refraction @ the micro-lens to the sensor ... should be a good...Show more →
I think it's possible (though I"m not certain) that the adapter itself might not be as wide in diameter as an original mount throughout it's length, which would be more of a possibility with say the diameter of the E-Mount vs say Canon EOS. This would, of course, never have been an issue with APS E-Mount adaptions. If the adapter throat is slightly more narrow than an original mount, that could cause the problem with fast FF lenses.
Edited on Oct 21, 2013 at 09:17 AM · View previous versions
Tariq Gibran wrote
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?I think it's possible (though I"m not certain) that the adapter itself might not be as wide in diameter as an original mount throughout it's length, which would be more of a possibility with say the diameter of the E-Mount vs say Canon EOS. This would, of course, never have been an issue with APS E-Mount adaptions. If the adapter throat is slightly more narrow than an original mount, that could cause the problem with fast FF lenses.
Edited on Oct 21, 2013 at 09:17 AM · View previous versions
Oct 21, 2013 at 09:15 AM
p.2 #10Sony a7/a7r limited by E-Mount?
RustyBug wrote:
Why would the SLR lens projection be any different (once adapted) on the A7R than on a native mount. The distance to the film plane will be the same (by virtue of the adapter) and the area covered by the projection will be the same @ FF. If it plays well on a current DLSR, it should play well on the A7R.
Bokeh cut off is due to mechanical obstruction of the mirror box. The throat size of the EF is much bigger than the E, and the lens is designed for such size, taken into account of the size of the mirror box as well. You can see that most cut-offs happen along the shorter side of the mirror box. Now, if you shrink the exit throat size further, the problem would be more pronounced.
Tariq Gibran wrote
Man, this thread really gives me pause with regard to going through with my A7r order. Now I'm concerned that even fast SLR lenses (1.4) could be problematic (at the very least in the bokeh area). Is this pretty much confirmed?Bokeh cut off is due to mechanical obstruction of the mirror box. The throat size of the EF is much bigger than the E, and the lens is designed for such size, taken into account of the size of the mirror box as well. You can see that most cut-offs happen along the shorter side of the mirror box. Now, if you shrink the exit throat size further, the problem would be more pronounced.
Oct 21, 2013 at 09:16 AM
p.2 #11Sony a7/a7r limited by E-Mount?
Okay, gotcha @ mechanical vignette for large diameter rear element.
Oct 21, 2013 at 09:18 AM
p.2 #12Sony a7/a7r limited by E-Mount?
Kolor-Pikker wrote:
[Flame shield activate]
I'm probably the only photographer that likes the chopped bokeh look.
That's because you are Russian...
sebboh wrote
sure bugs me.I'm probably the only photographer that likes the chopped bokeh look.
That's because you are Russian...
Oct 21, 2013 at 09:30 AM