Very good! Thank you...
I would stab a guess at that no pancake variety of lens will look to sharp in the corners with the SB adapter. That is quite a bit of coma there. Exit pupil distance is to short. What's interesting is that it still outperforms the Ultron 28.

Did you check them one or two stops down?

Makten wrote:
I don't think you can conclude that lenses getting hit by the mirror on an SLR will have problems with the Speedbooster.

You don't think it's a safe assumption that, if a lens with a protrusion (either rear element or shroud) like the R 15/3.5 has an issue with the SB but not the Canon FF mirror, lenses with longer protrusions that do foul the Canon mirror will also have problems with the SB? Seems logical enough to me.

theSuede wrote:
Very good! Thank you...
I would stab a guess at that no pancake variety of lens will look to sharp in the corners with the SB adapter. That is quite a bit of coma there. Exit pupil distance is to short. What's interesting is that it still outperforms the Ultron 28.

Did you check them one or two stops down?

It does help stopping down with the SB adapter.

Aperture 2.0, 2.8 and 4.0 with the SB, center and corner:

Did you refocus for the corner shot?

Dudewithoutape wrote:
Did you refocus for the corner shot?

Yes, I refocused for the corner. However with astigmatism the focus criterion is not well defined.

Dudewithoutape wrote:
Thank you alundeb for your contribution. Very interesting.

Edit - The nex 7 has reported bad corner performance, I wonder if results would actually be better from a 5N, etc.

There wasn't any help for the corners using the 5N with this lens. I think the color cast (or lack of) gives and indication.

One should do a reality check every once in a while.

Ask the question - Exactly what are we trying to do?
A 40mm f/2.8 lens has a nominal front pupil diameter of (40mm/2.8) = 14.3mm
The area of that pupil is pi*(14.3/2)^2 = 160mm˛

The pixel area of a NEX7 is about 0.004^2 = 0.000016 mm˛

To get perfection, we have to condense light hitting a 160mm˛ input area into a 0.000016mm˛ focal point.

Want to get that condensation rate in numbers? It's:
160 / 0.00016 = 10,000,000 : 1 (ten-million-to-one)

Relax the sharpness to a 3x3pixel area, and you still have a 1,000,000 to 1 condensation ratio.

Considering that we now combine two optical systems that weren't even custom made to complement each other, this result is amazing.

Awesome tests, Alundeb. I can't wait to see how some of the other pancakes out there, like the CV 40/2 and Pentax 43/1.9 (once a Pentax adapter is available,) perform.

I tried m42 lenses CZJ 35 2.4, Pentax M42 50mm 1.4, Jupiter 9 85mm, CZJ 135 3.5 and no problems with fitting. I found problems with OM lenses pin behind the lens so I didn't push the 21/3.5 as it wasn't fitting. I will check it more this weekend. I haven't checked the shots yet.

michael49 wrote:
mcbroomf wrote:
Michael,
I do have a 21/3.5 as well as the F2. I eyeballed it last night and thought it might be a problem, certainly not as clear an issue as the 18mm. I'll be checking measurements on my OMs tonight + a few others and the SB. I hope I'm wrong on a least some of the lenses. You can see a x-section schematic I put up in a gallery to see what I'm talking about. I'll add any photos taken from the weekend outings and the measurements for the arrow positions, together with the height of the fins for the lenses. I'll do as many as I can, mainly wide to normals.
...


Thanks for the information.

Personally, the lenses I would like to try with the Speedbooster would be:

Oly 21 3.5, Zeiss C/Y 28 2.8, C/Y 50 1.7, C/Y 85 2.8, CZJ 35 2.4, Nikkor AIS 55 3.5 macro and maybe the CZJ 135 3.5

Thanks for the test Alundeb. How is the manual focusing/af w/ SB+Canon 40mm on nex?

From photozone tests, Canon 40mm f2.8 has sharper corners compared to CV 40/2, but CV 40/2 might be better for manual focusing. I will try CV 40/2 next week.

douglasf13 wrote:
Awesome tests, Alundeb. I can't wait to see how some of the other pancakes out there, like the CV 40/2 and Pentax 43/1.9 (once a Pentax adapter is available,) perform.

douglasf13 wrote:
Awesome tests, Alundeb...

+1.

I know that this forum strongly favors alt lenses for some reason , but the Canon 40mm f/2.8 pancake is one of the best FF lens purchases I've made in quite a while (especially for the money).

serhan_ wrote:
I tried m42 lenses CZJ 35 2.4, Pentax M42 50mm 1.4, Jupiter 9 85mm, CZJ 135 3.5 and no problems with fitting. I found problems with OM lenses pin behind the lens so I didn't push the 21/3.5 as it wasn't fitting. I will check it more this weekend. I haven't checked the shots yet.
....

Thanks!! Too bad about the Oly 21 3.5.

theSuede wrote:
One should do a reality check every once in a while.

Ask the question - Exactly what are we trying to do?
A 40mm f/2.8 lens has a nominal front pupil diameter of (40mm/2.8) = 14.3mm
The area of that pupil is pi*(14.3/2)^2 = 160mm˛

The pixel area of a NEX7 is about 0.004^2 = 0.000016 mm˛

To get perfection, we have to condense light hitting a 160mm˛ input area into a 0.000016mm˛ focal point.

Want to get that condensation rate in numbers? It's:
160 / 0.00016 = 10,000,000 : 1 (ten-million-to-one)

Relax the sharpness to a 3x3pixel area, and you still have a 1,000,000 to 1 condensation ratio.

Considering that we now combine two optical systems that weren't even custom made to complement each other, this result is amazing.

Yes, it is amaizing both to think about the numbers (respect to you optical gurus), and to see that the SB actually is a useful tool.

The two obvoius costs of added distortion and lateral CA are of the kinds that can be corrected in SW with minimal negative impact.

The extreme corners look a little worse than the corners I showed (which correspond to about Imatest "corner" image height). One can say they did cut some corners to get the adapter small

About the SA / contrast reduction, I will try to look a bit more into that.

serhan_ wrote:
Thanks for the test Alundeb. How is the manual focusing/af w/ SB+Canon 40mm on nex?



Manual focusing with the Canon 40 mm STM focus by wire works like a charm. You don't get the feedbak and physical "memory of where you are", but you get the accuracy to make fine adjustments easily.

The CV 28/2 M lens is a bit difficult with the knob and short focus throw, but in sum about as usable as the Canon.

The CV 40/2 SLII I tried this morning is the best MF experience of the bunch with the ring and long focus throw. OTOH it has quite a bit focus shift.

michael49 wrote:
douglasf13 wrote:
Awesome tests, Alundeb...

+1.

I know that this forum strongly favors alt lenses for some reason , but the Canon 40mm f/2.8 pancake is one of the best FF lens purchases I've made in quite a while (especially for the money).

With the SB, Canon lenses is the new alt

We should have enough room here both for alternative solutions and alternative goals.

douglasf13 wrote:
Awesome tests, Alundeb. I can't wait to see how some of the other pancakes out there, like the CV 40/2 and Pentax 43/1.9 (once a Pentax adapter is available,) perform.

The enthusiasm from you guys keep me busy

CV 40/2 SL II, center and corner crops, wide open and one and two stops down.

The light has changed since yesterday (now the tungsten is mixed with window light) so don't make too much out of the colors.

I made a couple of quick/shakey measurements this morning after testing some lenses last night for the problem that prevents the shutter opening.
The lens inside the SB is ~8mm deep
The OM18 and 21/3.5 have a fin that protrudes 9mm. They are far enough in that even if my measurements are slightly off the fin would be perilously close. I'll try and do a better measurement tonight.
The OM21/2 seems to be ~8mm, but the 24/2 and 90/2 are 7mm and both fit OK.
The Pentax K 50/1.2 pin protrudes 9mm.
I'd mentioned that the 58/1.2 Rokkor wouldn't allow the shutter to open unless I wiggled it a bit (the mount to the SB is slightly loose), a 24mm VFC Rokkor that Jim converted for me, as well as a 24/1.4 FD that I bought converted and appears to have one of Jim's mounts (wide adapter) sit firmly and I can't get the shutter to open at all. I would guess that it shorting a couple of pins that the firmware doesn't like. Tonight I'll tape the pins to see if they start working. If they do perhaps Metabones could fix that with a firmware update (presumably they short the same pins on a Canon body yet don't affect it). By the way when I go into the menu it won't allow me to switch the Release W/O lens to ENABLE. I keep this option on ENABLE and when I put a lens on that's OK it defaults to that.
All of the c/y adapters/lenses I tried are OK .. I'll have to recheck the adapter I have on the 100/3.5 that seemed to black out the shutter.
35/1.4 EOS Rokinon is OK.
Tamron 90mm/2.5 52B is OK
35 FD T/S that Jim converted is OK but it has a different adapter, the width of the adapter is much thinner than the other ones so I guess it doesn't touch the pins in the SB.
Leica 28/2.8 Elmarit is OK (rear shroud removed), so is 35-70/4 and 100 Elmarit. I've not looked at a 50 'cron which was reported as having a problem on GDPI

Mike

alundeb wrote:
[....

With the SB, Canon lenses is the new alt
....

I was thinking that ... I put my 85/1.2 (Ver 1) on the Nex 7 and it reported F1.0

mcbroomf wrote:
alundeb wrote:
[....

With the SB, Canon lenses is the new alt
....

I was thinking that ... I put my 85/1.2 (Ver 1) on the Nex 7 and it reported F1.0

A shame the NEX cameras don't report anything below 1.0, you should actually get 0.9
Try Aperture priority, and you should find "1.0" at the two widest settings, one of them is actually 0.9
That is how it worked with my Canon 50 mm 1.0 L, but that lens with the SB is another story.

The adapter really looks short, it feels more like using an M adapter than an N adapter.

The design is also very nice, one end matching the mount and the other matching the lens.

On the NEX 7, small SLR lenses balance well and it doesn't look outlandish.

Now show me the OM-D with a 20 mm f/1.0 lens on it