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Praktica Pentacon 2.8 28mm
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PostPosted: Sat Mar 26, 2011 4:38 am    Post subject: Praktica Pentacon 2.8 28mm Reply with quote

Hiya folks

Picked this up a while back for a fiver in mint condition, it's in Praktica bayonet mount so I picked up an adapter for my EOS 5D.

Just some test shots, took these just after dawn on a very dull greay and overcast morning to test the contrast. I think it did quite well and if you nail the focus it's quite sharp.

All these shots are wide open to see how sharp she is and because I wanted to see what the bokeh was like.



100% crop:





100% crop:









100% crop:



PostPosted: Sat Mar 26, 2011 4:42 am    Post subject: Reply with quote

Sadly she won't quite hit infinity, I suppose this is due to the adapter throwing off the rear element to sensor distance.


PostPosted: Sat Mar 26, 2011 9:30 am    Post subject: Reply with quote

Interesting lens! There's a couple of shots here which make me think that it renders very nicely with some pop e.g. the clock shot.

The first two shots are suffering camera shake or are mis-focused though, so the 100% crops look much worse than they should be. Certainly on one of them the focus point is much lower down the pole.

EXIF data shows that these were shot on a 10D, have you managed to mount it on a 5D? My Praktica adapter won't work with my 5D which is a right pain.


PostPosted: Sat Mar 26, 2011 10:10 am    Post subject: Reply with quote

ManualFocus-G wrote:
Interesting lens! There's a couple of shots here which make me think that it renders very nicely with some pop e.g. the clock shot.

The first two shots are suffering camera shake or are mis-focused though, so the 100% crops look much worse than they should be. Certainly on one of them the focus point is much lower down the pole.

EXIF data shows that these were shot on a 10D, have you managed to mount it on a 5D? My Praktica adapter won't work with my 5D which is a right pain.


I'm afraid I don't have a 5D to try it on, sadly.

I have a 1.8 50mm Pentacon in PB mount and that works find on my 10D as well.

I agree about the clock shot, that one came out nice. I also agree about the first two, one is not quite in focus and the second looks like it has a bit of camera shake.

I'll take some more shots with this lens because I don't think this first set are that great, they were taken early morning in very dull, flat light. I posted the shots of the telephone pole to show the lack of distortion but that is to be expected on a APS-C sensor.

Is this lens a Meyer Optik after they changed the name to Pentacon?


PostPosted: Sat Mar 26, 2011 10:14 am    Post subject: Reply with quote

This lens was a new design made by the Pentacon / Praktica group but some say it has links back to the older Meyer / Pentacon 29/2.8.

Definately take it out again because it looks like it has real character! You state that you had a 5D at the beginning of the thread, I presume you meant 10D? The 10D has a 1.6x crop so you have an effective 45mm lens...a good walkaround length.


PostPosted: Sat Mar 26, 2011 10:22 am    Post subject: Reply with quote

ManualFocus-G wrote:
This lens was a new design made by the Pentacon / Praktica group but some say it has links back to the older Meyer / Pentacon 29/2.8.

Definately take it out again because it looks like it has real character! You state that you had a 5D at the beginning of the thread, I presume you meant 10D? The 10D has a 1.6x crop so you have an effective 45mm lens...a good walkaround length.


Yup, I have a 10D, If I wrote 5D it was a typo/brain fart, sorry.

I bought this lens with the idea of using it as a walkaround lens cos, as you say, it is about 45mm on this cam. I like the Pentacon 1.8 50 too, both lenses feel well built and have smooth focus and apertures, I like the way both handle. They might not be top of the range but they are German and the German didn't make many bad lenses (the Domiplan 2.8 50 being an obvious exception)

Just waiting for my batteries to recharge then I'll go get some more shots with this lens. Praktica Bayonet mount lenses are peanuts on ebay and I see quite a lot of these, the 1.8 50 is more common though, always lots of those listed.


PostPosted: Sat Mar 26, 2011 11:10 am    Post subject: Reply with quote

Was just looking at my Pentacon 28mm and I noticed that the black plastic piece at the back that protudes a bit far and causes prodlems on the 5d just pops out. This shortens the lens by 3mm. There is then a metal aperture arm protruding but you can just trim that back as it's not needed when used on an EOS with an adapter.

So without any drastic modding you should beable to use this lens on a 5D, just pop out the black pastic bit and trim 3mm off the aperture arm.


PostPosted: Sat Mar 26, 2011 11:12 am    Post subject: Reply with quote

Thanks for the info! I think the biggest problem is my adapter though...none of my Praktica lenses work on my 5D with it. In fact, the adapter won't even go on by itself Laughing Laughing


PostPosted: Sat Mar 26, 2011 11:15 am    Post subject: Reply with quote

ManualFocus-G wrote:
Thanks for the info! I think the biggest problem is my adapter though...none of my Praktica lenses work on my 5D with it. In fact, the adapter won't even go on by itself Laughing Laughing


Sounds like you have a bad adapter. I have both the 1.8 50 and 2.8 28 Pentacons in PB and they both fit and work fine. I also have 28-70 and 70-210 Pentacon zooms in PB and both those work too, I have two copies of the 28-70 which is a very solid all metal little lens that I think is made by Sigma.

I haven't tested the zooms yet, I paid peanuts for them and ended up with two 28-70 Sigmas because one came in a mixed lot of lenses.


Last edited by iangreenhalgh1 on Sat Mar 26, 2011 12:22 pm; edited 1 time in total


PostPosted: Sat Mar 26, 2011 11:20 am    Post subject: Reply with quote

Yep, Prakticars are cheap because they don't focus to infinity on Canon cameras. But...they do on the micro 4/3 cameras and Sony Nex models, so the prices are starting to rise!

I have the 28/2.8 Carl Zeiss Jena, 35/2.4 Carl Zeiss Jena, 50/1.8 Pentacon, 50/1.8 Pancolar, 35-70mm Pentacon and 80-200mm Pentacon. They all work fine on my 60D and 1000D, it's just the 5D that's the problem because of it's massive full frame mirror Sad


PostPosted: Sat Mar 26, 2011 12:23 pm    Post subject: Reply with quote

It's a real shame they won't hit infinity because they seem to be really nice lenses.

I've been looking at getting a Pancolar, would you say it is a better lens than the 50/1.8 Pentacon?


PostPosted: Sat Mar 26, 2011 1:35 pm    Post subject: Reply with quote

Congratulations on Prakticar 28/2.8. Someone sooner or later will find out
how nice this Prakticar (28/2.8 ) is, this is the time? Unfortunately OP's
adapter is still a bit too thick to get infinity focus, you need 0.40 mm thick
adapter. But a good adapter may cause an another problem of mirror hitting
the rear of the lens in many cases if you use FF EOS_5D.

So you may have to shave the base metal of your adapter or seek a "better"
lens which can focus to infinity, ie. some "badly" made lens due notoriously
inadequate QC (in the olden East Germany factory).

I shaved one of mine>


Or Alex's (hand made) PB->EF adapter > http://www.pbase.com/kkawakami/image/111994725

This (proto-type) adapter can reach infinity, but no Alex in sight nor this adapter on eBay.
Sigh.

Back to Prackticar 28/2.8: I do not have any linage info of this lens, but certainly
this lens and Orestegor 29/2.8 (made by PENTACON) M42 lens share 7 group 7 element
optical design. They might have improved its design for Prakticar 28/2.8 I have no idea.


PostPosted: Sat Mar 26, 2011 1:44 pm    Post subject: Reply with quote

It's another grey, dull overcast day here so low contrast lighting.

I shot a load more pics with the Pentacon 28/2.8, each one has a 100% crop after it.





























PostPosted: Sat Mar 26, 2011 2:04 pm    Post subject: Reply with quote

koji wrote:
Congratulations on Prakticar 28/2.8. Someone sooner or later will find out
how nice this Prakticar (28/2.8 ) is, this is the time? Unfortunately OP's
adapter is still a bit too thick to get infinity focus, you need 0.40 mm thick
adapter. But a good adapter may cause an another problem of mirror hitting
the rear of the lens in many cases if you use FF EOS_5D.

So you may have to shave the base metal of your adapter or seek a "better"
lens which can focus to infinity, ie. some "badly" made lens due notoriously
inadequate QC (in the olden East Germany factory).

I shaved one of mine>


Or Alex's (hand made) PB->EF adapter > http://www.pbase.com/kkawakami/image/111994725

This (proto-type) adapter can reach infinity, but no Alex in sight nor this adapter on eBay.
Sigh.

Back to Prackticar 28/2.8: I do not have any linage info of this lens, but certainly
this lens and Orestegor 29/2.8 (made by PENTACON) M42 lens share 7 group 7 element
optical design. They might have improved its design for Prakticar 28/2.8 I have no idea.


Thankyou for that info. I have seen Alex's adaptor and he had to do a lot of machining I recall, didn't he start with a Pentax K adaptor?

This is my copy of the Pentacon 28/2.8, it's been used a fair bit but is in really good condition and feels like it will last a lifetime.

The pics show how that back rear piece just pops out to reveal four screws that hold the PB mount in place. I wonder if it would be possible to remove this mount and replace it with either an EOS mount or an M42 mount and achieve infinity focus?








BTW, I took the images of the lens with my Pentacon 50/1.8, focus is a bit off on them but that's my fault, not the lens!