S
snaf
Guest
Thank you for good answer. But why do cosmicar 12.5mm f1.4 has 6 blades no 3 blades??? What are they difference ??
I think more blades are better for quality photo.
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Pentax 25mm f/1.4 C-mount seems to be very popular lately...
- Thread starter madmaxmedia
- Start date
Thank you for good answer. But why do cosmicar 12.5mm f1.4 has 6 blades no 3 blades??? What are they difference ??
I think more blades are better for quality photo.
madmaxmedia
New member
If you shoot mostly wide open it won't matter. I have a Computar 12.5mm f/1.3 and it has 3 blades. I think the blades will mostly just affect bokeh rendition, but with these lenses and these focal lengths, you shoot wide open for bokeh and stop down to get DOF.
pellicle
New member
Hi
searching here (seems to be a lost art among the internet spoon fed) will reveal some post of mine regarding exactly this lens.
I recommend you use the hawkpeng adaptor ... quite a bit on my blog so I won't dribble it all again here ;-)
some quick example of wide open vs stopped down at close focus
f1.3
f16
searching here (seems to be a lost art among the internet spoon fed) will reveal some post of mine regarding exactly this lens.
I recommend you use the hawkpeng adaptor ... quite a bit on my blog so I won't dribble it all again here ;-)
some quick example of wide open vs stopped down at close focus
f1.3
f16
madmaxmedia
New member
Thanks pellicle for that detailed blog post on the Computar and the hawkpeng adapter. I came across it earlier, and that is why I chose to go with the Computar + Hawkpeng- it looks like a mod that I can manage myself.
A question for anyone with the Pentax 25mm f/1.4- does it require modification to work with the Hawkpeng adapter? (I guess his eBay name is now hawks_factory or something like that.)
A question for anyone with the Pentax 25mm f/1.4- does it require modification to work with the Hawkpeng adapter? (I guess his eBay name is now hawks_factory or something like that.)
No. Just screw it at place.
RichA
New member
The Fuji has 8 blades and they are scalloped inward. Interesting design.
madmaxmedia
New member
Oops! Maybe my memory is serving me wrong...thanks!
I ordered the Pentax from CCCWorld, I'll see what I get.
I ordered the Pentax from CCCWorld, I'll see what I get.
V
Vivek
Guest
The Computar 25mm f/1.3, is one of the lenses I discovered and reported here.
The 3 bladed aperture does nothing negative.
It is (still) my favored lens in the 25mm FL range. I would recommend f/2.8, though even wide open, it isn't shabby.
Unlike the 12.5mm lenses, this one does cover the m4/3rds sensor (with slight corner vignetting that is easily dealt with in the post). There is a big difference in terms of usefulness.
madmaxmedia
New member
Hey Vivek,
Have you ever tried the Pentax/Cosmicar 25mm f/1.4? That one seems pretty good too, wondering how these 2 25mm lenses compare.
Have you ever tried the Pentax/Cosmicar 25mm f/1.4? That one seems pretty good too, wondering how these 2 25mm lenses compare.
V
Vivek
Guest
No, I have not. I will not either. 
Y.B.Hudson III
New member
Yehh... three bladed aperatures can be problematic when confronted with mediterranean light filtered through deciduous forest canopies...
madmaxmedia; I think you can like the Pentax.http://forum.getdpi.com/forum/showpost.php?p=81956&postcount=38
I used to bring it to the pub.
I used to bring it to the pub.
apicius9
New member
I remember those pics, very nice. I recently sold my Pentax (at one point I had over 20 25mm c-mounts...), but the main reason was not performance, only size: I have large fingers and this is just one of the smallest ones and I had to fiddle with it too much. Without all the alternatives I would definitely just have put up with that.
Stefan
Stefan
A
awty
Guest
Thanks for clearing that up for me.
V
Vivek
Guest
Yeah, that is a major problem. Triangles everywhere @ f/2.8.:ROTFL:Yehh... three bladed aperatures can be problematic when confronted with mediterranean light filtered through deciduous forest canopies...
Hi, and thank you.
Lol, yes, the size of that lens is a problem. Now with the Panny 20/1.7 most of those alternative lenses are on more or less permanent vacation. But sometimes, when wanting another look, they are fun to use.
Stefan, I just checked your big 25mm C-mount comparison. Thank you for posting it. Of the C-mount lenses I owned I liked the Kern Switar 26/1.1 the best. Now I have sold it and the only one still with me is the cute little Pentax. As said above it sees very little use. Do you still use any of your lenses? The main reason for me to give up on them is that I want my lenses to cover the sensor and after the arrival of the 20/1.7 there is no real size advantage to the C-mount.
/Jonas
/Jonas
madmaxmedia
New member
Hi Jonas,
Thanks for the link, I missed that post before- it's a really nice pic! I previously had a Wollensak, but my results were like Stefan's test shot- very hazy wide open.
I agree with you, in the long run I can see mainly using the Pana 20mm f/1.7. But that is only when it is in my budget. For now the MF equivalent will do at 1/10 the price. There is also something fun about these lenses (that imperfect c-mount look), although practically speaking the Pana 20mm wins out of course on most all counts.
Thanks for the link, I missed that post before- it's a really nice pic! I previously had a Wollensak, but my results were like Stefan's test shot- very hazy wide open.
I agree with you, in the long run I can see mainly using the Pana 20mm f/1.7. But that is only when it is in my budget. For now the MF equivalent will do at 1/10 the price.
There is also something fun about these lenses (that imperfect c-mount look), although practically speaking the Pana 20mm wins out of course on most all counts.
apicius9
New member
The main reasons I had all these c-mounts were a) a lack of impulse control on ebay and b) 2 opportunities to buy two larger lots of lenses, one of them with 20 mostly 25mm c-mounts - unfortunately, I never had a chance to pick up a 26/1.1 for a reasonable price.... That was long before the projected release of the Panny 20/1.7, so it was a lot of fun to play with the lenses. I have started selling off many of them (maybe a bit late, the prices are falling again...), but I will definitely keep a few, like one Angenieux 0.95 for its speed, the Cooke Kinic for its unusual bokeh, the Canon for its ease of use, and maybe one or two more. Eventually, I will also get the pancake. But for me, personally, the G1 and the fascination with the combo of old glass and new technology helped me rediscover the fun in photography. I had not looked through a viewfinder in a long time, and going back to the basics, having to manually focus and finding the patience and skills for that again, made this a very enjoyable experience for me.
I don't want to stray too far, but want to mention that I think not only the short c-mounts are interesting. The longer ones are very light and small on the G1 and some make excellent primes, like the Kern Macro Switar 75/1.9. I also like the Schneider Xenars which are totally undervalued on ebay IMHO.
Stefan
and b) 2 opportunities to buy two larger lots of lenses, one of them with 20 mostly 25mm c-mounts - unfortunately, I never had a chance to pick up a 26/1.1 for a reasonable price.... That was long before the projected release of the Panny 20/1.7, so it was a lot of fun to play with the lenses. I have started selling off many of them (maybe a bit late, the prices are falling again...), but I will definitely keep a few, like one Angenieux 0.95 for its speed, the Cooke Kinic for its unusual bokeh, the Canon for its ease of use, and maybe one or two more. Eventually, I will also get the pancake. But for me, personally, the G1 and the fascination with the combo of old glass and new technology helped me rediscover the fun in photography. I had not looked through a viewfinder in a long time, and going back to the basics, having to manually focus and finding the patience and skills for that again, made this a very enjoyable experience for me. I don't want to stray too far, but want to mention that I think not only the short c-mounts are interesting. The longer ones are very light and small on the G1 and some make excellent primes, like the Kern Macro Switar 75/1.9. I also like the Schneider Xenars which are totally undervalued on ebay IMHO.
Stefan
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