Biogon 35/2 and C Biogon 35/2.8

[noimmunity]

Since I will have access to both lenses, I would be happy to do a reasonable user comparison of the two lenses later this week, but I only have a vague notion of how to proceed.
Will use colour negative film to start (faster turnaround).
Same aperture, same light, same subject...same time, same bat channel?

 

[back alley]

no idea as to how to advise you.

maybe just shoot the same scene with each lens for a start.

i highly doubt that one is significantly sharper than the other but they might have a different look.

joe

 

[noimmunity]

thanks, joe.
i'll try to see if i can coax out some of that different look.
jon

 

[back alley]

if you decide to sell that 2.8 give me a shout...i'm close to listing my 35/2 and making the move.

 

[noimmunity]

comparison photos up

comparison photos up

hasty comparison photos: http://www.flickr.com/photos/areality4all/sets/72157605576262821/

I have a preference for the look of the new ZM C Biogon compared to the old. In color, it has more saturation and a little more contrast; perhaps also a little more vignetting. Tom A's comments about extra "snap" in the C Biogon are right on. Most people looking to choose one of the two would probably do best to decide based on speed (the extra stop of the 35/2) and handling (the small size of the 35/2.8) needs. But surely some will also be attracted to the look of the C Biogon. I'm interested in what people think.

It was pouring rain while I shot these photos and I was soaked. Kinda fun!

 

[sebastel]

thank you.

 

[noimmunity]

if you decide to sell that 2.8 give me a shout...i'm close to listing my 35/2 and making the move.

Hey, Joe, where are you at now on this one?

 

[back alley]

sitting on a big fence but leaning towards the 2.8.
have you got something in mind?

joe

 

[noimmunity]

i'm taking a bit of a guess, but from what i know of your shooting style, i'd say that the 35/2.8 would work better for you, esp. on the R4A. but you've already got such a sweet set up, there might not be any reason to switch!

on my side, cindy's not gonna wanna part with the 35/2 i gave her, and i'm not gonna wanna part with my new C Biogon. i'll use it mostly on the RD-1 and the R4A.

but two stops is a lot, so the nokton 35/1.2 on the ZI still has a place.

since you have three other 35s, it would be interesting if you do take the C Biogon plunge to do a comparison of the four.

 

[noimmunity]

it also looks to me, based on the first roll of comparison photos, that the C Biogon preserves more shadow detail than the Biogon.

 

[noimmunity]

thank you.

you're welcome.

 

[jjovin]

I could not tell much difference from your images other than perhaps that you mislabeled the f-stop on the Biogon.
I have a biogon and I am keeping it.
Thanks for posting the images.
Zoran

 

[noimmunity]

The differences between the two lenses are subtle enough that if you can't tell how my labelling system works, you won't get it.

If in doubt, refer to the tags. The titles of the images also indicate which lens was used: "Bio" = ZM Biogon 35/2; "CBio" = ZM C Biogon 35/2.8 . The number in the title is the f-stop at which the photograph was taken. Between these TWO indications, it would be hard NOT to figure it out. My guess is that you were just in a rush...


So, keep your Biogon. It's a great lens and will allow you to take shots at f/2.0 that you can't take with an f/2.8 lens. And while you're at it, slow down a little so you don't fall prey to your own lack of generosity.

 

[horosu]

Thanks for your comparison. I have the same impression as you: the C Biogon retains more shadow detail than the Biogon, which is fantastic.

I think that tiny lens will be my next purchase.

 

[nzeeman]

from those test shots it seems that biogon is a bit wider than cbiogon.

 

[jjovin]

My perception is that the depths of field of the images of Oxford College, for example,
taken with the Biogon at f2.8 and the C-Biogon taken at f4 are very close, much closer than the depth of filed in the images labeled Biogon 4 and C-Biogon 4. The same holds, for other images and other fstops. Unless there is some new physics involved, this led me to believe that perhaps the images were mislabeled. So if I compare images that appear to have the same depth of field, and do not go by their labeling, then I can hardly see any difference between the two lenses, and with an additional stop, my choice is to keep my Biogon.
I spent quite a bit of time looking at the images (more than your comment suggests) and I am quite aware of your labeling. My conclusion is based on comparing images that appear to have the same depth of field and I had no intention to include anything negative in my previous comments. I would take your comment about my lack of generosity without knowing me personally, only as a poor joke and thanks again for posting the images.
Zoran

 

[noimmunity]

The comments about depth of field are interesting. Is this discrepancy noticeable in other images besides those taken of Oxford College? I won't have the time to take a look until Monday.

FWIW, The Biogon just returned from Oberkochen where the flange to focal distance was adjusted. Would that make a difference? I scrupulously took notes about f-stop in the field, but Murphy's Law is omnipresent, and I am not going to insist that I could not possibly have made an error.

What would be impossible, however, is to reliably infer that remarks about mislabeling are really supposed to refer to depth-of-field discrepancies. The only thing I could tell for sure is that you would impute user error to others without the courtesy of a dialogue.

Erwin Puts recently wrote: "And after you selected the product, you are still insecure and continue to seek assurance that you made a wise choice." Perhaps your repeated comments about keeping your Biogon reveal what is really weighing on your mind. Keep your Biogon and be happy!

 

[jjovin]

The only thing I could tell for sure is that you would impute user error to others without the courtesy of a dialogue.

Erwin Puts recently wrote: "And after you selected the product, you are still insecure and continue to seek assurance that you made a wise choice." Perhaps your repeated comments about keeping your Biogon reveal what is really weighing on your mind. Keep your Biogon and be happy!

Even in my first comment I said "PERHAPS" you mislabeled the f-stop on the Biogon. That does not imply the claim that you did.
Clarifying in my second comment, if I compare images that seem to me to have the same depth of field, I can not see any significant difference between the lenses to give up an extra stop in a Biogon, although I like compact lenses.
I am aware of Erwin Puts writings and rarely agree with him.
However he has his place on the web. I also see equipment as tool for photography and change it without regrets if I see something else that suits my needs better. Quoting him here misses the point.
I think we should engage in a more constructive discussion.
I appreciate the fact that you posted the images on the web and I often use such postings in my decision to get lenses.
I think you misunderstood my comment that perhaps you mislabeled the fstops, and took it in a negative way even tough
no negativity was intended by me. It is perhaps my unsuccessful way to state that I compared the images that appeared to me to have the same depth of field and that way I did not see as much difference between the lenses as others stated in their comments. So, please take a look yourself again and compare images that appear to have the same depth of field.
Cheers,
Zoran

 

[noimmunity]

Zoran,

Rain has delayed some weekend plans so I'm using the time to look at the images again. I also double checked to make sure that the flickr photos didn't get mislabelled in the uploading.

I believe that there is no error. The f-stops as reported are accurate, especially when taken as a whole.

So how to explain the discrepancy?

I offer two ideas:

1) i didn't use a tripod and the FOV is slightly different.

2) there is a difference between the aperture values of the two, due to sample variation or some other reason.
I noticed on at least two occasions that the same f stop (2.8) on the two lenses would produce different shutter speeds through the AE. At 2.8, the AE reading for the Biogon would be one stop faster than the equivalent reading for the C Biogon. Turning the aperture ring of the Biogon one third of a stop would solve the discrepancy. Yet I tried to make sure that the shutter speeds and aperture values would be the same when I took the photos.

I knew before I started what a can of worms this might be, henced asked for advice on how to compare (at the top of this thread), yet received none. Knew I should've used a tripod but hate the things. I'm a little too casual and a little too amatueurish. I've added a caveat emptor to all of the example photos on my flickr album mentioning the imprecise conditions in which the comparison was undertaken.

Jon

 

[jjovin]

Jon,
Looking at Oxford College, CBio4 and Bio2.8 appear to have just about the same amount of blur
of the background and midrange objects even though it appears that you took a small step back when you took the image with the Biogon. It appears that you also took a step back when you took
Bio4, and yet the mid-range and background objects appear sharper than on Cbio4.
Therefore, Bio2.8 and Cbio4 is a more relevant comparison to me. And between these 2 images,
I do not see as much difference as others have pointed out.
This depth of field difference seems to be present throughout the Oxford College series.
I do not see it on other images. What I see on some other images is that the lighting conditions seem
to be slightly different between the shots and that may give the appearance that the lenses are quite different. For example, on Garden 2 Biogon seems to have much more shadow detail on the left side of the image than the CBiogon. This is contrary to what others have been saying. However, the brightest area of the image seems to shift from left to right as one switches between Biogon and CBiogon.
On some other images, CBiogon seems to show a bit of vignetting at 2.8.
So, to conclude, if I take various other factors into account that exist between different shots,
it would be hard for me to decide that one lens is better than the other. Perhaps others would still see significant differences, but this is what my eyes see.
Best wishes,
Zoran