leica_thread_mat
Newbie
Thanks David,
I'm sorry i didnt explain my issue very well. It's edge to edge sharpness that concerns me.
I have included samples.
I'm using a Leica M240, i have about 20 Canon, Nikon and Topcor LTM lenses but this is the worst edge to edge sharpness performance i've seen. Even my Canon 25mm is a stellar performer.
Do not get me wrong i do love this lens though.
I'm sorry i didnt explain my issue very well. It's edge to edge sharpness that concerns me.
I have included samples.
I'm using a Leica M240, i have about 20 Canon, Nikon and Topcor LTM lenses but this is the worst edge to edge sharpness performance i've seen. Even my Canon 25mm is a stellar performer.
Do not get me wrong i do love this lens though.
Attachments
David Murphy
Mentor
I like the photos - the color rendition is excellent!
I can't really notice obvious edge sharpness degradation in the posted images, but I'm sure you're right based on inspecting the originals. I have seen some obvious edge degradation on wider LTM lenses from the 50's, but not usually on the faster ones, which is how I'd classify this lens (for its era). Sharpening with photo processing software will certainly ameliorate the problem if you want to go that route (I often do).
I can't really notice obvious edge sharpness degradation in the posted images, but I'm sure you're right based on inspecting the originals. I have seen some obvious edge degradation on wider LTM lenses from the 50's, but not usually on the faster ones, which is how I'd classify this lens (for its era). Sharpening with photo processing software will certainly ameliorate the problem if you want to go that route (I often do).
David Murphy
Mentor
Your lens BTW, sells on eBay for about $1000 and up. It's quite a collectible.
leica_thread_mat
Newbie
Thanks David. Yes i got it for $200 USD, had to clean the internal elements but it came up well!
xayraa33
rangefinder user and fancier
My sample of that Topcor 3.5cm f2.8 lens does not vignette anymore than my Canon 35mm f2.8 or my Nikkor 3.5 cm f2.5 lens. In fact the Topcor produces a more 3D like image in the photos than the other two Japanese made competitors from that same 1950s era.
That is the charm of the old classic lenses...they give the photos a different look than do the clinically sharp and crisp image of modern high class lenses.
Very nice photos, BTW
That is the charm of the old classic lenses...they give the photos a different look than do the clinically sharp and crisp image of modern high class lenses.
Very nice photos, BTW
leica_thread_mat
Newbie
Thanks,
Do you notice soft edges even @ f11? Just trying to work out if something is misaligned on my copy.
My Canon 35mm 1.5 and f2 dont do this.
xayraa33
rangefinder user and fancier
I noticed a bit of vignetting at f2.8 but it is very pleasant vignetting and it is vignetting very little at f4 and disappears by f5.6 really not much different from my two samples of the Nikkor 3.5 cm f2.5 lens and the Topcor produces a more pleasing 3D image than either the Nikkors or my Canon 35mm f2.8 lens
I would say that there is a problem with your sample of that Topcor lens....these were 1st class lenses in their time....Tokyo Kogaku was a very conservative lens maker that cut no corners or expense in making their products.
TenEleven
Well-known
Way late to this thread, but I just wanted to point out that these lenses were computed for film. And on film this Topcors performance is nothing short of stunning from wide open already. By f/4 vignetting is down to a minimum and the corners are very sharp, too. Agree with xayraa33's assesment that this is a stunner of a lens and Tokyo Kogaku made basically nothing but top-shelf optics.
What kind of performance you get on digital such as the OP's M240 is gonna be a total crapshoot. I do not think that this is a sample issue as I found a Japanese blog who also tested his on digital and the performance was considerably inferior in a similar way to the OP's complaint.
Without going into too much detail, the requirements to get a sharp image out of a digital sensor, plus the filter stack itself changing the optical formula - are very, very different for what is required for film. I wish people would stop trying to screw "old lenses" on their digital cameras and then proclaiming that "xxx lens sucks" when this lens was never meant to perform under such an environment.
What kind of performance you get on digital such as the OP's M240 is gonna be a total crapshoot. I do not think that this is a sample issue as I found a Japanese blog who also tested his on digital and the performance was considerably inferior in a similar way to the OP's complaint.
Without going into too much detail, the requirements to get a sharp image out of a digital sensor, plus the filter stack itself changing the optical formula - are very, very different for what is required for film. I wish people would stop trying to screw "old lenses" on their digital cameras and then proclaiming that "xxx lens sucks" when this lens was never meant to perform under such an environment.