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05-16-2016, 03:31 AM   #46
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QuoteOriginally posted by IgorZ Quote
This is going to sound like a stupid question, but I am trying to figure out the difference between 67 and 645. The 67 has a bigger format, but both use the same film, right? How does that work? There is also quite a price difference. I see a 645 body listed for $50 canadian on Ebay, but the cheapest 67 goes for around $300. Is it that much better?
Medium format film is also known as roll film because it's just a roll. It's limited to around 6cm on one side of the exposure because that's the height of the film, but the other dimension is only limited by the camera and lenses used, hence different formats all with one maximum dimension of 6cm. 645 is 6x4.5, 67 is 6x7 but there are also many 6x6 cameras and even other formats.

In general, the bigger the format the bigger the camera and lenses and therefore more expensive. 645 is the smallest medium format size but still around 2.5x larger than 135 format film and the difference in quality and depth of field is very noticeable. I'd love a 6x7 camera but they're just too expensive. However, the smaller 645 format means the gear is lighter and more portable (I recently took mine on a trip to Paris, which I'm not sure I'd have been able to do with a 67).

The original Pentax 645 is an excellent camera and from what I've read, suffers less from the mechanical faults that plague many medium format cameras, especially SLRs. I would thoroughly recommend the 645 with a standard 75mm f/2.8 lens but there are similar cameras available for a similar price from Mamiya, Bronica and others. Many TLRs can be had for a good price too and they are mostly 6x6. Yashica models are probably the most common and cheap, though they are well built with good optics.

The cheapest way to get into medium format is to get an old folding camera (but as these can be very old make sure that the optics are fungus-free, the shutter works properly and there are no holes in the bellows). These cameras are obviously much less flexible in what they can do than a good SLR or TLR though.

05-16-2016, 07:05 AM   #47
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QuoteOriginally posted by Jonathan Mac Quote
Medium format film is also known as roll film because it's just a roll. It's limited to around 6cm on one side of the exposure because that's the height of the film, but the other dimension is only limited by the camera and lenses used, hence different formats all with one maximum dimension of 6cm. 645 is 6x4.5, 67 is 6x7 but there are also many 6x6 cameras and even other formats.

In general, the bigger the format the bigger the camera and lenses and therefore more expensive. 645 is the smallest medium format size but still around 2.5x larger than 135 format film and the difference in quality and depth of field is very noticeable. I'd love a 6x7 camera but they're just too expensive. However, the smaller 645 format means the gear is lighter and more portable (I recently took mine on a trip to Paris, which I'm not sure I'd have been able to do with a 67).

The original Pentax 645 is an excellent camera and from what I've read, suffers less from the mechanical faults that plague many medium format cameras, especially SLRs. I would thoroughly recommend the 645 with a standard 75mm f/2.8 lens but there are similar cameras available for a similar price from Mamiya, Bronica and others. Many TLRs can be had for a good price too and they are mostly 6x6. Yashica models are probably the most common and cheap, though they are well built with good optics.

The cheapest way to get into medium format is to get an old folding camera (but as these can be very old make sure that the optics are fungus-free, the shutter works properly and there are no holes in the bellows). These cameras are obviously much less flexible in what they can do than a good SLR or TLR though.
Thank you, Jonathan Mac. It is definitely a different experience, and quite a learning curve... Just unboxed my new 645, waiting for the lenses to arrive. Weight was definitely one of considerations - with 3 kids to chase, I didn't think I could do it with a 2.3kg 6x7... TLR's I thought would be too much of a jump - at least the 645 looks like a big SLR... I missed out on the 75mm, but am waiting for an 80mm Biogon to arrive...
05-17-2016, 09:09 AM   #48
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QuoteOriginally posted by IgorZ Quote
. I missed out on the 75mm, but am waiting for an 80mm Biogon to arrive...
Biogon is in Carl Zeiss speech a real [non-retro] wide angle lens.

I think you mean the VEB Carl Zeiss Jena Biometar 2.8/80mm , which they produced for the KW/VEB Pentacon Praktisix/ Pentasix (P6) medium format (MF) camera.
I hope you know it`s some of the weaker Carl Zeiss lenses. Better not to use it at f2.8.
In the seventies Carl Zeiss produced a variation of the lens in 4.0/80mm - which was imho more honest - but not so good for marketing.
VEB Carl Zeiss lost his honesty, when they took over VEB Pentacon in the early eighties.

Personnally I use it at my film Ptx645N - I´am coming from the P6 system - if I need a small travelling lens. The Zeiss CF 3.5 /100m is better - but bigger.

To add - a fourtnight ago I had the opportunity to use a Ptx 645Z in workshop as rent. I took all my lens with me , from whom I expected trouble* with the Ptx645Z sensor. The badest lens wasn´t the Biometar 2.8/80 .


* in german " Problemkinder" which sounds better than troubleshooters
05-17-2016, 10:22 AM   #49
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QuoteOriginally posted by veraikon Quote
.......
I think you mean the VEB Carl Zeiss Jena Biometar 2.8/80mm , which they produced for the KW/VEB Pentacon Praktisix/ Pentasix (P6) medium format (MF) camera.
I hope you know it`s some of the weaker Carl Zeiss lenses. Better not to use it at f2.8.
It's worth noting that the CZJ Biometar 2.8/80 was recalculated in 1979 and lenses produced after that time were noticeably better than the earlier versions.

Bob

05-17-2016, 11:34 AM   #50
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QuoteOriginally posted by veraikon Quote
Biogon is in Carl Zeiss speech a real [non-retro] wide angle lens.

I think you mean the VEB Carl Zeiss Jena Biometar 2.8/80mm , which they produced for the KW/VEB Pentacon Praktisix/ Pentasix (P6) medium format (MF) camera.
I hope you know it`s some of the weaker Carl Zeiss lenses. Better not to use it at f2.8.
In the seventies Carl Zeiss produced a variation of the lens in 4.0/80mm - which was imho more honest - but not so good for marketing.
VEB Carl Zeiss lost his honesty, when they took over VEB Pentacon in the early eighties.

Personnally I use it at my film Ptx645N - I´am coming from the P6 system - if I need a small travelling lens. The Zeiss CF 3.5 /100m is better - but bigger.

To add - a fourtnight ago I had the opportunity to use a Ptx 645Z in workshop as rent. I took all my lens with me , from whom I expected trouble* with the Ptx645Z sensor. The badest lens wasn´t the Biometar 2.8/80 .


* in german " Problemkinder" which sounds better than troubleshooters
You are right, it is a Biometar I am waiting for. I don't really know much about this lens. The only thing I know is that I have an old CZJ 50mm f2.8 which I really like in B&W, and I wanted to try a CZJ lens in MF as well. It seems like CZ makes pretty bad lenses - I was told that Japanese-made CZ lenses are not as good either So I gather Biometar is pretty soft? This brings up the point which I have been pondering for some time - how do you guys select which lens to get? Aside from focal length and aperture considerations, how do you decide? I can't decide if I like a lens just by looking at someone's pictures, I feel like I need to spend some time with the lens to make that decision. Since I don't have any MF lenses right now, I am pretty open (and ignorant about them), so I am looking at old pentacon, Pentax, Kiev lenses, but not really sure how to go about it...

---------- Post added 05-17-16 at 11:35 AM ----------

QuoteOriginally posted by Bob L Quote
It's worth noting that the CZJ Biometar 2.8/80 was recalculated in 1979 and lenses produced after that time were noticeably better than the earlier versions.

Bob
The one I picked up is a black MC version, so I guess it is recent-ish... Not sure when it was made though...
05-17-2016, 11:37 AM   #51
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QuoteOriginally posted by Bob L Quote
It's worth noting that the CZJ Biometar 2.8/80 was recalculated in 1979 and lenses produced after that time were noticeably better than the earlier versions.

Bob
I concur - the late-model one I've had for a good while on my Pentacon is arguably one of the most beautiful renderers I have - and I have some gems. It brings magic even to mundane.


---------- Post added 05-17-16 at 11:44 AM ----------

QuoteOriginally posted by Jonathan Mac Quote
The cheapest way to get into medium format is to get an old folding camera (but as these can be very old make sure that the optics are fungus-free, the shutter works properly and there are no holes in the bellows). These cameras are obviously much less flexible in what they can do than a good SLR or TLR though.
Agree with this wholeheartedly - the old folders can easily become an addiction. But more than that, if I'm just walking out the door, or even going on a hike, more often than not I will throw one my old Frankas or Zeiss-Ikons in my pack over the 645 or 67 based on nothing more than weight, size and simplicity. My Franka takes up less space and weight than my MX and the images I get from it are phenomenal. You certainly need to be aware (as mentioned) that these are for the most part very old and delicate machines, but there really are only a few areas to go wrong and if serviced, cared for and stored well, they'll last another 50-80 years.
05-17-2016, 01:03 PM   #52
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QuoteOriginally posted by IgorZ Quote
So I gather Biometar is pretty soft?
Not neccessarilly pretty soft but unlikely to be blisteringly sharp either. That said, if you're using for portraits and the corners of the image are all outside the DoF then do those soft corners detract from the image?

QuoteOriginally posted by IgorZ Quote
This brings up the point which I have been pondering for some time - how do you guys select which lens to get? Aside from focal length and aperture considerations, how do you decide? I can't decide if I like a lens just by looking at someone's pictures, I feel like I need to spend some time with the lens to make that decision. Since I don't have any MF lenses right now, I am pretty open (and ignorant about them), so I am looking at old pentacon, Pentax, Kiev lenses, but not really sure how to go about it...

---------- Post added 05-17-16 at 11:35 AM ----------

There is a modern obsession with corner to corner sharpness and the quality of bokeh and rendering has been relegated to "desireable but not essential". Only you can decide how much sharpness you'll sacrifice in order to buy or use a lens based on the other factors. The uncorrected aberrations that rob the resolving power are often the very same aberrations that serve to give lenses their signature rendering. I have no fewer than five different 300mm f/4 lenses and they are all capable of producing a different version of the same subject.
QuoteOriginally posted by IgorZ Quote

The one I picked up is a black MC version, so I guess it is recent-ish... Not sure when it was made though...
The black MC versions, of which there are two, both pre-date and post-date the recalculation. It's reasonably safe to assume that if the edge of the focus ring is black (not silver/un-anodised) then it's a post 1980 version. Whatever the version, it's 27 years old (or older).

Bob
05-18-2016, 08:44 AM   #53
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QuoteOriginally posted by Bob L Quote
Not neccessarilly pretty soft but unlikely to be blisteringly sharp either. That said, if you're using for portraits and the corners of the image are all outside the DoF then do those soft corners detract from the image?


There is a modern obsession with corner to corner sharpness and the quality of bokeh and rendering has been relegated to "desireable but not essential". Only you can decide how much sharpness you'll sacrifice in order to buy or use a lens based on the other factors. The uncorrected aberrations that rob the resolving power are often the very same aberrations that serve to give lenses their signature rendering. I have no fewer than five different 300mm f/4 lenses and they are all capable of producing a different version of the same subject.

The black MC versions, of which there are two, both pre-date and post-date the recalculation. It's reasonably safe to assume that if the edge of the focus ring is black (not silver/un-anodised) then it's a post 1980 version. Whatever the version, it's 27 years old (or older).

Bob
Hello Bob,

Thank you! Sharpness has never been the main criteria, otherwise picking lenses would have been easy - just looking at the lpm tables... The way I think of it, I have an image I want to create, and I want a lens that will do it, so if I want rich colours, I go to my M lenses, if I want warm colours, I go for the comrades - Jupiter 9 or 37A, etc. With K/M42 lenses, I feel it is easier because I am dealing with a somewhat known quantity. If I want (which I do), to create an image like my K28 f3.5 does, but need a different focal length, I'll go and get another K lens. The other case that is fairly easy is a lens that has some special characteristics, like swirly bokeh. If I want that, I know I need to get a Petzval lens, the new lensbaby, or old Helios 40-2 or to some extent 44 - 2.

The problem with MF for me is that I am really starting from ground zero - I have never tried any A 645 or pentacon 6 lenses, or MF for that matter, so I am stumbling in the dark a bit, focal length considerations aside. I looked at some lens reviews, but as I mentioned before, I don't really find them that informative, as they often involve pixel-peeping, which I don't do anyway. Hence my question - how do you guys decide which lens to get?

05-18-2016, 09:14 AM   #54
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QuoteOriginally posted by IgorZ Quote
Hello Bob,

Thank you! Sharpness has never been the main criteria, otherwise picking lenses would have been easy - just looking at the lpm tables... The way I think of it, I have an image I want to create, and I want a lens that will do it, so if I want rich colours, I go to my M lenses, if I want warm colours, I go for the comrades - Jupiter 9 or 37A, etc. With K/M42 lenses, I feel it is easier because I am dealing with a somewhat known quantity. If I want (which I do), to create an image like my K28 f3.5 does, but need a different focal length, I'll go and get another K lens. The other case that is fairly easy is a lens that has some special characteristics, like swirly bokeh. If I want that, I know I need to get a Petzval lens, the new lensbaby, or old Helios 40-2 or to some extent 44 - 2.

The problem with MF for me is that I am really starting from ground zero - I have never tried any A 645 or pentacon 6 lenses, or MF for that matter, so I am stumbling in the dark a bit, focal length considerations aside. I looked at some lens reviews, but as I mentioned before, I don't really find them that informative, as they often involve pixel-peeping, which I don't do anyway. Hence my question - how do you guys decide which lens to get?
I like reviews for sample photos and to point out any reoccurring defect with design or workmanship. I also factor price just because that is reality. And I'm willing to take more of a gamble on an inexpensive lens.
My first few 645 lenses were bought almost entirely based on price and focal length. They turned out to be nice usable lenses that are still in rotation.
Old inexpensive Pentax A lenses for 645 are generally all still very sharp so I don't worry about that much and just jump in with the bargain lenses.
05-18-2016, 09:21 AM   #55
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QuoteOriginally posted by Bob L Quote
It's worth noting that the CZJ Biometar 2.8/80 was recalculated in 1979 and lenses produced after that time were noticeably better than the earlier versions.

Bob
Bob that´s right (but no recalculation more a modification).
Exactly this version (Version"4") of the VEB Carl Zeiss Jena Biometar 2.8/80mm should be build as a Biometar 4.0/85mm. A first [Test-]batch was made in this version, which is now a collectors item.

Carsten Bobsin and Rene Schulz wrote in their Praktisix/Pentsix article series in Photodeal (a german journal for analoge Photo gear):
QuoteQuote:
...
Im Laufe der Zeit hatten sich einige Fotografen zu Wort gemeldet, dass das Objektiv [Biometar 2.8/80mm] bei offener Blende vignettiere.
1977 rechnete Christa Dietsch, ebenfalls rechnende Optikerin bei Zeiss, das Objektiv nach und stellte fest, dass es
wirklich vignettiert und auch die Brennweite von 80 mm um 4 mm verfehlt wurde.
Es kam zum Vorschlag, diese Fehler richtigzustellen indem nicht das Objektiv neu errechnet werden, sondern korrekt
bezeichnet werden sollte – eben als Biometar 4/85.
In den folgenden Jahren wurden mehrere Musterobjektive angefertigt. Sie sollten als Ansichtsexemplare dienen. Den Fertigungsunterlagen
bei Zeiss zufolge wurden 61 Stück angefertigt. Daneben sind noch zwei weitere bekannt. Die echte Stückzahl
könnte im Bereich 65-85 liegen. ..... Es lässt sich zwar die Blende 2,8 einstellen, dieser Wert wurde aber nicht graviert. Auch die
Schärfentiefeskala und der Infrarotindex fehlen. Letztlich wurde der Vorschlag abgelehnt.
Ein Biometar 4/85 war einfach nicht so werbewirksam wie ein 2,8/80.
..
source: Carsten Bobsin, René Schulze (2012): Zeiss-Objektive mit Praktisix-Anschluss. Photodeal III/2012, p.64-65

In the late seventies the incorparation of VEB Pentacon and Meyer Görlitz in the VE Kombinat Carl Zeiss
was obvious.
So Carl Zeiss Jena lost his interest in relabeling the modified Biometar on marketing* purposes.

I think we should accept Christa Dietschs advice - even if f2.8 is still engraved** on the lens on marketing purposes.

*As a late (and not in the GDR) born, I wonder always that there was anything like a marketing department in the VEBs ,
but I was told there exists even ads in TV .
** on Carl Zeiss Oberkochen lenses it would be printed - and eraseable without problems.
05-18-2016, 09:38 AM   #56
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QuoteOriginally posted by veraikon Quote
Bob that´s right (but no recalculation more a modification).
Exactly this version (Version"4") of the VEB Carl Zeiss Jena Biometar 2.8/80mm should be build as a Biometar 4.0/85mm. A first [Test-]batch was made in this version, which is now a collectors item.
++++
I fully understand where the engineers are coming from. The f-stop ratio is a physical fact and "undisputable" whilst the light lost through vignetting would give us the T-stop. The lens is surely f/2.8 but, at the same time, "t/4"......not something that the marketing gurus would want to portray.

Sadly we still see such degraded performance today. I have a Zeiss 2/135 APO Sonnar ZE (35mm for Canon) which is more than 3 stops down in the corners.....it still has remarkable optics though.

Still, lets not divert from Igor's quest.....

Bob
05-18-2016, 01:14 PM   #57
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QuoteOriginally posted by mattb123 Quote
I like reviews for sample photos and to point out any reoccurring defect with design or workmanship. I also factor price just because that is reality. And I'm willing to take more of a gamble on an inexpensive lens.
My first few 645 lenses were bought almost entirely based on price and focal length. They turned out to be nice usable lenses that are still in rotation.
Old inexpensive Pentax A lenses for 645 are generally all still very sharp so I don't worry about that much and just jump in with the bargain lenses.
That has been my strategy so far as well: price and focal length...
05-28-2016, 07:55 PM   #58
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I think the biotar should be arriving early next week, so I've been thinking how to fit 645 into my camera lineup. As of late I have been using K28 with K-5, and an 85mm with MZ-7. I think the only wisdom behind this setup is that I really like K 28, and since I am shooting Portra, it seemed like MZ-7 needed a portrait lens... I am awaiting the 80mm CZ and a 65mm Mir (3?). I guess these lenses cover the "normal" range, so I've been thinking if I should keep wide angle on the K-5, "normal" range on the 645, and maybe go 135mm on MZ-7. Would that make sense, or is medium format particularly good for, say, wide angle? Or should I stop building theories and just go and take pictures ?
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