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So, what is a good manual normal lens now?

m3photo

New member
Re: Diameters and infinity

I think you mean rear diameter 'too big.'
The Tevidon will cover the sensor in 16:9 mode. There are ways for them to focus to infinity. :)
1)
Diameter of rear lens on C/V Nokton - roughly 2.5mm
Diameter of rear lens on C/Z Tevidon - roughly 1.4mm
Diameter of rear lens on Cosmicar 8.5mm - roughly 0.7mm
My conclusion was - the smaller it is the worse it gets (?)

3) If there's a dark circle all the way round, how can it cover the sensor in 16:9?

2)
Please say how to make them focus to infinity.

Thanks.
 
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monza

Active member
Re: Diameters and infinity

1)
Diameter of rear lens on C/V Nokton - roughly 2.5mm
Diameter of rear lens on C/Z Tevidon - roughly 1.4mm
Diameter of rear lens on Cosmicar 8.5mm - roughly 0.7mm
My conclusion was - the smaller it is the worse it gets (?)

3) If there's a dark circle all the way round, how can it cover the sensor in 16:9?

2)
Please say how to make them focus to infinity.

Thanks.
It's the diameter of the rear of the lens MOUNT (as opposed to the diameter of the glass) that is the critical dimension, when fitting the lens to the c-mount adapter. It is a physical conflict that prevents infinity focus.

The Cosmicar is not going to cover the sensor, as it's a 2/3" format lens.
 

m3photo

New member
Re: diameter of the rear of the lens MOUNT

It's the diameter of the rear of the lens MOUNT (as opposed to the diameter of the glass) that is the critical dimension, when fitting the lens to the c-mount adapter. It is a physical conflict that prevents infinity focus.

The Cosmicar is not going to cover the sensor, as it's a 2/3" format lens.
Sorry I'm dumber than you think ...
My simple reasoning is this: If the lens is a c-mount it fits on the c-mount adapter; if the diameter of the rear of the lens MOUNT is wrong it won't fit.
I thought that the difference in the space between the rear element and the film plane/sensor would be the physical conflict that prevents infinity focus.

If the 2/3" format lens is not the type to play with on the G1, what should we be looking for in c-mount lenses for it?
 

monza

Active member
Bear in mind that the flange distance of c-mount is ~17.5mm which is less than the flange distance of micro 4/3 (~20mm.) This means the screw threads for the c-mount adapter are recessed into the lens mount of the G1. This limits the rear diameter of c-mount lenses for compatibility.

The back focal length doesn't seem to be an issue with most c-mount lenses that are of interest (i.e., the distance from the rear element to the sensor, or in this case the limitation is the distance from the rear element to the shutter of the G1.)

1" format is a 25.4mm image circle; 22mm is the m4/3 image circle.

Hope this helps!
 

m3photo

New member
Re: Kind Help

Hope this helps!
Very much so, thank you.
How did you manage to get the Tevidon to work at infinity? I've been sanding it down for three days non-stop (only kidding) and still haven't got very far beyond about 40cm!
 

f6cvalkyrie

Well-known member
Re: Adapters

I got a 24mm f/2 Nikkor from Ebay for this very reason and I'm hoping there'll be an F/M43 adapter for it soon ...
Hi,

maybe you could use the double convertor solution mentionned in the sticky topic ? I'm doing that with my 30 y old Nikon lenses, and it works fine.

C U
Rafael
 
W

wblynch

Guest
Anyone heard news of an OM to G1 adapter?

I would like to avoid the intermediate OM-4/3-G1 stack.
 

antara

New member
Robert
How can one find out when this adapter will appear, and how much it will cost.
Hopefully it will save me From the $160 for the G1/4/3 adapter.
Antara
 

monza

Active member
I would recommend emailing or calling Novoflex for an update...

NOVOFLEX Praezisionstechnik GmbH
Brahmsstr. 7, 87700 Memmingen
Tel.: +49 8331 88888 Fax: +49 8331 47174
eMail: [email protected]
 

Jonas

Active member
A great number of photos with the Kern Switar 25mm/1.4, as well as Angenieux 25mm F1.4 and 0.95 and other lenses
Hi Peter,

Thank you for the link. I have been browsing that thread a couple of times the last two days.

What I see is that the small C-mount lenses aren't to my taste. The bokeh is in most cases distracting. I did like the Konica 28/1.8 images. But that lens seem big and expensive.

regards, /Jonas
 

Jonas

Active member
Sorry to be so ignorant, but what is "bokeh" ?
Ah, bokeh is a must know when visiting modern photography forums...

It's a short and handy word for "the quality of the rendering of the out of focus parts of the image".

EDIT:
How on earth did rafael turn into f6cvalkyrie?


Cheers,

--
Jonas
 

Jonas

Active member
I decided to give the Pentax 25/1.4 a try:

Above; wide open, handheld, up close and nosy.

Here is a crop, no sharpening:


Thank you monza for pointing me to the lens.

It is too small, fun, sharp in the center, smeary at the borders, badly corrected, does pretty well with a hood attached, nice bokeh, cheap, vignettes and doesn't really cover the sensor. I like it. It isn't really for serious work but good enough in most situations and totally OK for portraits and most snaps.

Cheers, /Jonas
 

LizaWitz

New member
It is too small, fun, sharp in the center, smeary at the borders, badly corrected, does pretty well with a hood attached, nice bokeh, cheap, vignettes and doesn't really cover the sensor. I like it. It isn't really for serious work but good enough in most situations and totally OK for portraits and most snaps.

Cheers, /Jonas

Ok so we're still looking for a good manual normal (and hopefully cheap and fast) lens, right?

Any suggestions? Also if it wasn't 35mm sized that would be great. (I want it all apparently, and I guess I wont' get it until th 20mm 1.7 comes out.)

Or did someone find the holy grail and I missed it?
 

monza

Active member
It is too small, fun, sharp in the center, smeary at the borders, badly corrected, does pretty well with a hood attached, nice bokeh, cheap, vignettes and doesn't really cover the sensor. I like it. It isn't really for serious work but good enough in most situations and totally OK for portraits and most snaps.
Jonas, that's pretty much sums it up. :) It does have some barrel distortion but not as much as the Tevidon. Easy to correct in PS.

Have you tried 16:9? I'm wondering if the smearing is not the Leica-style RF lens smearing, but just "I'm really trying to cover all the sensor but I can't quite do it" smearing.



100% crop, no sharpening, f/1.4:

 
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