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

barjohn

New member
I shot test targets using the kit lens and the Nikon lens. When I looked in LR the corner targets were soft and blurry but when I used Raw developer they nearly matched the center for resolution and sharpness. The kit lens showed huge barrel distortion in Raw developer but looked very good in LR. I think someone else hit on the issue. LR, PS and Silkypix are all doing lens correction even when they lack good data and thus distorting the corners. Raw Developer is not.
 

monza

Active member
I can't see any difference. Looking at a shot taken with a Nikkor 24/2.8, I can open the raw file directly in Raw Developer, and put it side by side on the screen with the DNG version of the same image, and the corners look identical, assuming all sharpening is turned off in PS as well as RD.
 

Terry

New member
I can't see any difference. Looking at a shot taken with a Nikkor 24/2.8, I can open the raw file directly in Raw Developer, and put it side by side on the screen with the DNG version of the same image, and the corners look identical, assuming all sharpening is turned off in PS as well as RD.
When you talk about the DNG version, what are you doing with the original raw file? Just not sure I understand the workflow.
 

monza

Active member
To open in PS I first convert to DNG, as I have CS3, not CS4. The raw file is unaltered, so I open that with Raw Developer which can read G1 RAW files directly.
 
N

nei1

Guest
I realise the work gone into this and it is even to me mildly interesting,however not labeling things in a logical way does appear to be slightly sadistic.Guess Im just not sufficiently interested.Well done anyway...........Neil
 

Cindy Flood

Super Moderator
Please help me understand

Please help me understand.

I went back and found a nothing photo from last week. I downloaded a trial of Raw developer. I didn't put any sharpening or other adjustments. I only tweaked the exposure a tad. I then re-sized it for the web in CS3. This was shot with g1 and a CV28 f/1.9 using a JM original M adapter. Please tell me where it is smeared, because I am not seeing it in my photos.

Please understand, this would be a trash shot and I have in no way run my usual workflow on it. I am only looking for help understanding this problem.
 
R

Ranger 9

Guest
Ok, I give up, what does the f second letter stand for? For the first letter S Seiko and M for Matsu****o were not hard. But it says corner and center yet when you click on the images to get the full size image it always shows a corner.
The second letter designates whether it's a center or corner cut: "M" for medial (center) and "P" for peripheral (corner.) Yeah, I know, "medial" and "peripheral" are kind of pretentious -- but if I had just abbreviated "center" and "corner," they both would have come out "C", wouldn't they?


Apologies to all who were bored or frustrated by my "guessing game" labels. But often when looking at online lens-test images, I suspect that viewers' reactions are conditioned by their knowledge of what camera/lens was used for each photo: "I could see plainly that the ZeiNiLeiCan images have that ineffable inner isness of the whatness that only ZeiNiLeiCan can produce." So I thought it might be more interesting to make this a "blindfold" test... although a lot of that interest turned out to be negated by the fact that so many of the images were darn near identical.
 

peterv

New member
Hi Cindy, I don't see any corner distortion / smear in your shot. But than again, it is quite difficult of not impossible to see on a small image posted on the net. At a 100% if it's there, I'm sure you'll see it. And besides, at what aperture did you take this shot?
Wide open it's much more noticeable than stopped down to f5,6
Hope this helps, Peter
 

monza

Active member
If I may make a comment...how much of an issue is this, if it can't be seen except in 100% crops? I know I don't print anything at 100%. If I did, I would not be using a G1 anyway...and even then, it's unlikely to cause a problem on the vast majority of the types of shots I take.
 

peterv

New member
Hi monza, you're right, if you don't make full size prints and shoot at smaller apertures, why bother if you don't see any artifacts.
 

monza

Active member
Well, I tend to shoot like Ranger...it's either pretty much wide open, or stopped down with flash in a studio.

If it's wide open, the vast majority of the time, the only thing that will be 'smeared' a bit is the bokeh. :) So no issue there.
 

Jonas

Active member
If I may make a comment...how much of an issue is this, if it can't be seen except in 100% crops? (...)
I think it is about versatility. In the best of worlds I would like to be able to use my camera and my lens for everything. That's impossible. But I would like to be able to have just one 25-28mm lens. A fast one for my snaps and dark places. Then it should work as well as possible also for my building documentation project.

Well, that was my starting point.

I now realize that I can't use the G1 for this. The base ISO noise is too high and I'm having problems getting shallow DOF. So, I'm right now thinking of keeping the CV28/2 Ultron. I like the way it draws and it is good enough for daily snaps and more.
 

monza

Active member
I use all my lenses wide open...from a Nokton 40, Summarit-M (my only two M mount lenses) to all my Nikkors (especially my favorite the 24/2.8 which has great bokeh) to the Canon 1.2 to the Pen F Zuikos from 20 to 250. And I have some fast c mount lenses on the way for testing...

Does 'base noise' mean ISO 100?
 

m3photo

New member
Re: fast c mount lenses on the way for testing...

And I have some fast c mount lenses on the way for testing...
Do please keep us posted on this one - not only on the testing but on the when/where/how much of purchasing if possible.
 

Jonas

Active member
I use all my lenses wide open...(...)And I have some fast c mount lenses on the way for testing...(...)Does 'base noise' mean ISO 100?
I use the aperture opening that suits the image the best (if I have the time and the eye). Often that is the same as wide open, sometimes the bokeh is considerably improved by stopping down a notch or two, sometimes I need wide (large?) DOF.

With a larger sensor camera I get more picky about the aperture value.

Base ISO = ISO100 on the G1, yes. I come from a 5D and when cropping the G1 images I find them noisy.

It will be very interesting to see images from the c-mount lenses you have on your way. The Pentax you mentioned looks interesting. In the other thread (What is a good manual normal now?) I mentioned something about the Pentax not being a so called High MP lens - and thought that to be good.

Now I'm not as sure about that. I can't find any MTF curves or anything alike that for the Pentax lens and after having read more about CCTV lenses I understand high resolution usually isn't their forte. Well, I guess we'll know in a couple of days.
 

Jonas

Active member
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