Sean Reid's observations on M mount lenses on the G1

[monza]

From the link that Ranger 9 posted (very interesting reading*, thanks) this appears to be the issue. The 4/3 lenses are designed for the sensor.

What interests me at this point is investigation into which adapted lenses exhibit this, and is it strictly related to focal length or to other factors specific to individual lenses. I suppose it is possible (probable?) that some lenses are naturally telecentric and therefore should work fine on the G1.

*They need a proofreader: "To maximize the performance of the image sensor, the camera must be designed so that the light is straight even on the periphery of even on the periphery of the image sensor surface."

 

[monza]

The first adapter I got from a well known German manufacturer was too short, and focussed way past infinity. The replacement they sent me two days ago will not focus past 10 meters, so back into the box it goes. I'm sure they will eventually get it right.

I think I may just ask for a refund at this point...

 

[Ranger 9]

*They need a proofreader: "To maximize the performance of the image sensor, the camera must be designed so that the light is straight even on the periphery of even on the periphery of the image sensor surface."

Obviously that section was added by the Department of Redundancy Department. I liked the diagram headed "TELECENTRIC OPITAL SYSTEM," too. (If I had laughed any harder, I might have gotten hurt badly enough to have to go to the opital myself.)

Of course they're very smart people for whom English is not a native language. But it still would have been astute to have a fluent English-speaker give it a dekko.

 

[Woody Campbell]

I'll probably get flamed for this but . . . shooting a g1 with a 28 chron side by wide with an M8 and a 50mm lux under controlled conditions gives very similar results to what Sean and others have seen. If you own an M8 I see no reason to have a G1, at least until the 20mm pancake is released and proves itself.

 

[monza]

I see no need for flaming. But it's probably premature to draw any conclusions.

What is needed is for some easy testing of as many lenses as possible, to determine which ones exhibit the problem, and to what degree.

In my own tests (as well as others I have spoken to) this isn't an across the board problem with all M lenses.

The 40 Nokton seems fine from my own testing. The 50 ZM Planar seems fine (not my test.) I have been perusing flickr and downloading 'original' size images for a look-see. In the few examples I've inspected so far, the CV 12 seems fine (some edge degradation but nothing major to me), as well as the 35/1.2 Nokton. This of course is unscientific as some of the images could be cropped, which is why a group test effort is in order. Preferably done by people who own both M8s and G1s, I might add.

Now, on to more flickr research.

 

[m3photo]

Re: Cosina-Voigtländer Nokton 50mm f/1.5

Hard to judge from a 3-D target like the coiled snake, but the lower right and left corners look a little weird.

Well, I know it's not the typical brick wall test shot but a real life image is what we go out and photograph and hope to get good results from our equipment when we do.
The lower right and left corners look "a little weird" as you say because as I said it was shot at f/1.5 and as it's through glass you can see the snake's pushed up against it.
My idea when posting this image was to show an example of a non-Lumix lens working correctly at both sides even when opened up completely so as to dissipate the worry that all such lenses might be prone to aberrations in this respect.

 

[m3photo]

Re: Proof reading...

. . . shooting a g1 with a 28 chron side by wide with an M8 and a 50mm lux under controlled conditions .

"Side by wide"? Is that instead of "side by telephoto"? ;-)

 

[Jonas]

OT: Replying to post 16 here. It seems as I can't view the thread in Threaded view and click the Quote button: doing so make the forum software pop up another post (quoted).

Peter: No, I'm not 100% sure the adapter doesn't degrade the corners. But I am as sure I can be as a non technical guy... As I said, the adapter is a lens holder adding nothing but air. You can also see the corners, sharp and nice, when stopped down. I wouldn't blame the adapter.

Seeing your images at first I was sure it was veiling flare due to an old Summilux construction. Now you say you don't get corners looking like that when using the lens on your M cameras. That again make me suspect the angle of the light rays. That's not a new topic - but certainly a disappointment as I thought the problem was solved now with the new flatter sensor designs. Maybe it isn't solved, I don't know and would like to see some input from somebody with more knowledge.

So, I'm just stuck with my claims and question marks from my earlier reply (post #9).

In worst case we are facing a situation, as Martin hints in post #20, where we are better off with Panasonic G lenses only. Should that be it I'm not sure what to do with my G1...

regards, /Jonas

 

[peterv]

Hi Jonas, I understand what you're saying. I too would like people with more insight than me to come forward and explain what's going on here.

Trying to reply to your thoughts one by one:

Peter: No, I'm not 100% sure the adapter doesn't degrade the corners. But I am as sure I can be as a non technical guy... As I said, the adapter is a lens holder adding nothing but air. You can also see the corners, sharp and nice, when stopped down. I wouldn't blame the adapter.

I'm thinking maybe there are different things going on at the same time, e.g. CA in the corners, reflection from the inside of the adapter while using large apertures, and no communication between the lens and the camera. Most likely, there are more factors at work here that I haven't thought of.

Seeing your images at first I was sure it was veiling flare due to an old Summilux construction. Now you say you don't get corners looking like that when using the lens on your M cameras. That again make me suspect the angle of the light rays. That's not a new topic - but certainly a disappointment as I thought the problem was solved now with the new flatter sensor designs. Maybe it isn't solved, I don't know and would like to see some input from somebody with more knowledge.

Right, I think eventually we as users should put together a list with lenses that can be used on the G1 and other future µFT camera's by trial and error and experimenting. Perhaps people that shoot black and white and do not watch their pictures 100% don't notice any 'problems' or maybe they just don't care. That's fine, of course.

So, I'm just stuck with my claims and question marks from my earlier reply (post #9).

Me too

In worst case we are facing a situation, as Martin hints in post #20, where we are better off with Panasonic G lenses only. Should that be it I'm not sure what to do with my G1...

That could very well be the case indeed.
As for me, I bought the G1 for a project where I want to shoot with the 75, 90 and 135 and perhaps even the 280 mm Visolens. So if this will turn out to work fine, I'll be content.
That said, all in all I'm happy I bought into this system. I like the small size and weight, and as I said, I love the Summilux 25 mm

Kind regards, Peter

 

[Guy Mancuso]

I have not read this review nor will I. Also have not read really many posts on the 28 cron on the G1 but when i was in Sedona on my way to Moab this was the combo I grabbed when we where scouting. I used John's adapter to make the connection for the 28 cron to my newly purchased G1. Now these are just playing around and nothing serious in any way in regards to testing. Obviously I would have done things different. Anyway i shot sort of wide open to around F8 and not sure which is which either but here they are processed in ACR with default sharpening and you make the call but some look pretty good to me. Have about 10 or so. Here they come

 

[Guy Mancuso]

Some more, maybe stopped down a shade more if I recall which is not easy around 5.6

 

[Guy Mancuso]

Honestly they look fine but so does the Kit lens and I would not go out and buy Leica glass for the G1 but the g1 serves as a nice backup for the M8 and it gives you several other nice benefits. Obviously cost a load less so theft , damage and such are not even a real worry and for the money it is damn good and i got some really nice keepers from it and the long zoom is a real advantage in the system and at 200mm really good see the Moab thread in sunset bar and you will see some long shots that are really nice with detail. Anyway thought I would post what i had, juts to add to your thought patterns.

 

[Guy Mancuso]

Just to add I shot my P25 back also and overall things look in place as they should . Did not notice any issues on the G1

 

[Jonas]

Well Guy, what you add to my thought pattern is a dosis of confusion... In your post #31 (I still can't click the Quote button or the Quote+ button when replyinh. there is the text from another post coming up if doing so) you have the second series of images with red rocks and cliffs. The sensor is small and the lens is stopped down to around f/5.6 or maybe even 8. Surely the borders of image 1,2 and 3 in that series look sharper? Image 4 look better.

Now the images are small and not made for this purpose. I may need to wash my eyes. Whatever. What do you think about them if you look closer at your originals?

regards, /Jonas

 

[Guy Mancuso]

@ and 3 i think I was pretty wide open of the wood piles if not wide open . Let me look atthe EXIF on shutter which usually is a hint

 

[Guy Mancuso]

I was pretty wide open here in the first four

1 1/320
2 1/640
3 1/500
4 1/800

Shutter speeds which indicates i was pretty wide open. We had sun but was not a blazing sun and in and out too. I most likely was around 2.8 or F4 on these first 4

 

[Martin S]

I have been thinking about this issue, and I believe that we need to do more testing to see if this is a real world issue, or a strictly test issue.

The forum members who have M (CV) glass, and G1's could test this on as many lenses as are available before we make any hasty decisions about the compatibility, or utility of the G1, and M, or CV lenses.

Sean's testing is fair, and accurate for the one lens that he tested. We should see how broad a problem this really is, and how does it affect real world images.

M or CV glass was obviously designed for film use, and the apparent periphery effects with the G1 should not come as a surprise (although the magnitude of the effect did to me!!).

Thanks.

Martin

 

[Guy Mancuso]

Checking the rest I did stop down more

5 1/125
6 1/250
7 1/60
8 1/250
9 1/200
10 1/500

Keep a eye on the light since it was in and out but after 4 i started stopping down which makes sense to me i usually try things wide open at first than start stopping down.

 

[Guy Mancuso]

Well I agree more testing is never a bad thing and certain lenses may not work as well , that I can also see. I did shoot the 50 cron also which looked good also . See if i can find a couple of those. What i did was lent my camera to someone on the workshop since I did not like his camera and as the owner/ instructor i wanted to make sure he went home with images. So I gave him the G1 to use for 4 days, so never got the chance to really work it. But I made a 84 year old man a very happy camper and that is what counts. LOL

 

[woodyspedden]

I'll probably get flamed for this but . . . shooting a g1 with a 28 chron side by wide with an M8 and a 50mm lux under controlled conditions gives very similar results to what Sean and others have seen. If you own an M8 I see no reason to have a G1, at least until the 20mm pancake is released and proves itself.

Woody

I agree with the exception of using it as a backup. If the IQ is good enough there is no point in paying another $3 or $4K for a second M8. I now have two M8's but would sell one if a $599 kit would get the job done

Woody