MF camera with AE and idiot proof....

Well I don't know about fool proof, but my ETRS + AEII prism + speedgrip is a fast bit of gear for semi auto...I normally take my own exposure readings for shots, but had to take some quick shots of my grandchildren playing with a wheelbarrow and they were moving from sun to shade (from over hanging trees) and on top of that the sun was going in and out behinds clouds. Well s*d that for working out exposure when in a hurry, so set the prism for auto exposure......well it's a bus ride 8 miles to snappy snaps to dev the two rolls of film for £7 and let's see how the ETRS coped, erm and see if Snappy snaps are any good.

Well snappy snaps dev the two films in 1 hour for £7 and someone had an idea for protecting the negs as they used to 35mm cassettes taped together :eek:....looking at the negs the exposures looks spot on when the ETRS was set on semi auto.
Now the fun begins in scanning as the film expired in 2002 and wasn't stored in the freezer. :eek:
 
So in theory the lenses on the mamiya TLRs which are 6x6 would work on the 645s as they are larger than the area needed similar to how FF lenses work on crop cameras? Does the focal length alter? That's assuming there aren't any electronic gubbins in either or both having matching electronic gubbins?

As mentioned one's a TLR the other a SLR... it highlights that the mounts really matter. Basically the flange dstances and the physical and electronic elements of the mounts are used by the maker to control whether you can mount different lenses (sometimes for good reasons). Pentax is legendary in allowing nearly all older PK lenses to mount on all newer cameras including digital, with obvious restrictions. Others have had "families" of lenses that are compatible. Among the sadder cases to my mind are Bronica SQ lenses not mounting on the ETR range, and Mamiya 7 lenses not mounting on the 6.
 
I still say check out the Pentax 645N...Ive got one and its .....wow.... with the 75mm AF lens
 
Think about computability with digital backs. One day you might get one; the older lot is getting more affordable. Contax? This one has lovely Zeiss glass made for it, and I think AF.
 
Also if you want to have auto exposure you'll have to get the Pentax 67II version as both of the previous types are fully manual. Thew 67II sells for a much greater price as it has AE, multi/centre weighted/spot metering and is much newer in comparison.
 
I found how heavy it was not long after writing... I'd probably need some kind of burly chap to walk around with me carrying it. The guy in the sigma rocket launcher ad would do the job nicely ;)
 
Its a 6
It has to be a 6, nothin else will do.
You can go round in circles weighing up the ins and outs of everything, but they will all have caveats.
The closest thing to what you describe is a 6, not without its own caveats mind, but it ticks the important elements.
Yes......its expensive
If I was to suggest something else it would be based on what I think is important, for instance I could settle for a 6x7 Fuji, but thats no metering and fixed lens which blows your original essentials out of the water, so its a 6......or a 7 with a bigger bag....:)
 
Its a 6
It has to be a 6, nothin else will do.
You can go round in circles weighing up the ins and outs of everything, but they will all have caveats.
The closest thing to what you describe is a 6, not without its own caveats mind, but it ticks the important elements.
Yes......its expensive
If I was to suggest something else it would be based on what I think is important, for instance I could settle for a 6x7 Fuji, but thats no metering and fixed lens which blows your original essentials out of the water, so its a 6......or a 7 with a bigger bag....:)

Basically this :)

Lovely and portable, and beautiful lenses. The only problem is it's not large format :D
 
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I thought that at first, but then realised that the minimum size of the image circle is defined by the length of the diagonal, not the side.

diameter = sqrt(side1*side1 + side2*side2)

I haven't got a square root on the nearest available calculator, but for 6*6 that works out at the square root of 72 (around 8.5?), while for 645 it's the square root of 56.25 (around 7.5?).

It does seem really stupid for some of these companies to have designed lenses so close to the minimum, although the pressure to make them smaller must be a factor. But many systems are hampered by a lack of available lenses; with greater cross-compatibility users could have a wider set of lenses to use for the same investment by the maker. The Mamiya 6 and 7 spring to mind as particularly egregious cases, given the small difference in image circle there.

Maybe there are other things like updating the electrical connections?

You're right, of course - thanks, Chris. I need to think a bit more before I post :)
 
Did you sell your 6, Chris?

No, still got the pair of them. Took them out for the first time in a while last weekend up in the peaks and it felt very odd not carrying a giant backpack full of LF gear. A pair of them with the 3 lenses is pretty much the perfect non-LF kit in my eyes. The 50 stays on one all day, with the 75 and 150 swapping on and off the other as required, and it all fits in a Billingham with room to spare :D
 
You're right, of course - thanks, Chris. I need to think a bit more before I post :)

Actually, I think you were right first time. If a lens projects an image circle which can cover 6cm, then it must have a diameter of at least that; and hence a lens that can cover 6x4.5 will cover 6x6. Even Chris' figures back that up, as a diameter of 7.5cm is still larger than 6. It is possible that the makers might insert internal baffles to restrict the non image forming light that gets through; but that's more a physical property than an optical one of the lens. If fitted, this would scupper the use of such a lens. Easy to test in practice if you gain access to a lens. The only medium format lenses I have are for the Mamiya RZ67 which has a rotating back and hence covers 7cm both ways.
 
Actually, I think you were right first time. If a lens projects an image circle which can cover 6cm, then it must have a diameter of at least that; and hence a lens that can cover 6x4.5 will cover 6x6. Even Chris' figures back that up, as a diameter of 7.5cm is still larger than 6. It is possible that the makers might insert internal baffles to restrict the non image forming light that gets through; but that's more a physical property than an optical one of the lens. If fitted, this would scupper the use of such a lens. Easy to test in practice if you gain access to a lens. The only medium format lenses I have are for the Mamiya RZ67 which has a rotating back and hence covers 7cm both ways.

Stephen, I still think you're wrong; it isn't the sides but the diagonal that counts. You can fit a 6*4.5 rectangle inside a smaller circle than a 6*6 square needs... (make it extreme to see: a 6*0.1 rectangle, basically a line, only needs a circle just over 6cm in diameter).
 
If you can fit a 6x4.5 rectangle inside a circle, given that a circle is - well - circular, surely you can rotate the rectangle inside it? And if so, after a 90 degree rotation, you'll have a 6mm rectangle at right angles to where you started, and coverage for 6cm both horiztonally and vertically. If you can show me I'm wrong, I'll apologise and retract; but as this isn't the point of the thread, I bow out on this point here.
 
If you can fit a 6x4.5 rectangle inside a circle, given that a circle is - well - circular, surely you can rotate the rectangle inside it? And if so, after a 90 degree rotation, you'll have a 6mm rectangle at right angles to where you started, and coverage for 6cm both horiztonally and vertically. If you can show me I'm wrong, I'll apologise and retract; but as this isn't the point of the thread, I bow out on this point here.

Two 6x4.5 rectangles at 90 degrees to each other don't cover the same area as one 6x6 square.

Edit: a quick image I knocked up. You can rotate the 6x45 through an entire 360 degrees within the circle of the 6x45 lens, but it still doesn't cover the corners of a 6x6 square.

View attachment 18557
 
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H'mm what's all this circle and rectangles :rolleyes: confuses me.....It's simple:- crop a 6X6 horizontally or vertically by 1.5cm and it's the same as a 6X4.5cm neg...or have I missed something :p
 
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H'mm what's all this circle and rectangles :rolleyes: confuses me.....It's simple:- crop a 6X6 horizontally or vertically by 1.5cm and it's the same as a 6X4.5cm neg...or have I missed something :p

It is a nice way of saying 645 lenses are useless on 6x6 system
 
They should have standardised on rb67 lenses, that would cover all their systems and you'd get the best bit of the lens on the smaller systems.


Every system would be enormous but it would be standard...
 
If only it was that simple :)

Its all about film plane distances and focal plane shutters v leaf shutters and varying film formats.

Mamiya make lots of different camera types and formats, to make all lenses compatible with all camera types and formats sounds at best impractical, more likely.....impossible.
Its much easier for manufacturers of single format cameras like Nikon to implement compatibility across their range.
 
Two 6x4.5 rectangles at 90 degrees to each other don't cover the same area as one 6x6 square.

Edit: a quick image I knocked up. You can rotate the 6x45 through an entire 360 degrees within the circle of the 6x45 lens, but it still doesn't cover the corners of a 6x6 square.

View attachment 18557

Keith, brilliant! I spent most of my walk trying to work out how to describe that in words since I haven't any simple drawing tools (that I know how to use) to draw it.

Its all about film plane distances and focal plane shutters v leaf shutters and varying film formats.

Mamiya make lots of different camera types and formats, to make all lenses compatible with all camera types and formats sounds at best impractical, more likely.....impossible.
Its much easier for manufacturers of single format cameras like Nikon to implement compatibility across their range.

You're right, John, though I'm still not sure why they couldn't have made the Mamiya 7 lenses work on the 6... oh, I suppose that would have reduced the incentive for 6 owners to buy 7s! D*mn marketing.
 
I think its because peeps wanted a wider lens than the 50mm available for the 6.
The 7 has a 43 and an external viewfinder, at the long end a 210, to accomodate all this extra coverage I guess maybe they had to have a design rethink.
As a consequence, perhaps this is why the 7 doesn't fold either, I dunno...just guessing.
The 6 was designed as a compact lightweight travel MF system, by the time you've got all the glass for the 7, the finders and accounted for its additional size because it doesn't collapse into itself, its still a great camera but a very different package to lug about compared with the 6.
I suppose if a wider lens couldn't be made for the 6 due to its design, why make any of the 7 range fit the 6. :)
Maybe the 6 is just a happy cockup...lol
 
If you can fit a 6x4.5 rectangle inside a circle, given that a circle is - well - circular, surely you can rotate the rectangle inside it? And if so, after a 90 degree rotation, you'll have a 6mm rectangle at right angles to where you started, and coverage for 6cm both horiztonally and vertically. If you can show me I'm wrong, I'll apologise and retract; but as this isn't the point of the thread, I bow out on this point here.
What you say about rotating the rectangle is right, but although that's true, you'd be missing the corners of the image, as shown in abdoujaparov's scheme.
 
Agreed. I totally missed that point (indeed, all four of them :)). Thanks for pointing it out (pun intended) - I appreciate it.
 
I have it on good authority that there will be a Mamiya 645 Pro with AE head, power winder, 2 lenses and two backs in the classifieds soon. ;)
 
If a lens projects an image circle which can cover 6cm, then it must have a diameter of at least that; and hence a lens that can cover 6x4.5 will cover 6x6. Even Chris' figures back that up, as a diameter of 7.5cm is still larger than 6.

I think this has been answered above but I realised I was wrong when I twigged that with a diameter of 6cm, the circle would only fit inside the 6x6 square, not reaching the corners as @abdoujaparov illustrated. Chris was correct in that the longest dimension the image circle would need to cover (and therefore the diameter of the circle) is the diagonal of the desired size of the negative.
 
I'm going round in circles looking at the mamiya 645 pro, then mamiya 6 (with big budget) then pentax 645Nii and pentax 67 and Bronica SQAi.

Square format and slightly landscape formats are appealing. I'm not so sure about the skinnier 645. Checking out current photos shows I'm 90%+ in landscape ie wider width shots.
 
If you live near Edinburgh you could borrow my 645Pro.
 
If I had my time again I'd go oblong, maybe 645, more likely 6x8 or 6x9.
now that I'm back heavily in to printing, 6x6 is a constant OCD trigger..lol
Square composition never fits oblong paper, cropping wastes 20% of the film, printing square wastes paper unless you want to end up with test strips coming out of your earholes.
6x7 is not oblong enough, 6x8 or 6x9 would be good but that's a different enlarger now, so........:hungover:
 
Square composition never fits oblong paper, cropping wastes 20% of the film
....:hungover:
Don't think of it as 20% waste but 20% more flexibility :thumbs:
 
If you never print anything there is nothing to go to waste in any format...
 
10x8 and contact print.......its the only way....:cool:



You don't want to print anything never ?........ever ??............everever.????

Nope. Odd canvas but that's it... thinking about doing medium format slide so I can make little windows though ;)
 
Nope. Odd canvas but that's it... thinking about doing medium format slide so I can make little windows though ;)

The bigger the better then, slides are beautifull, so beautiful that's all I shot for yonks.

Its a complete diabolical doohickey that we can't print slide.

Clearly irrefutable proof I've not done anything right since I started with this stupid film crap.
 
I'm going round in circles looking at the mamiya 645 pro, then mamiya 6 (with big budget) then pentax 645Nii and pentax 67 and Bronica SQAi.

Square format and slightly landscape formats are appealing. I'm not so sure about the skinnier 645. Checking out current photos shows I'm 90%+ in landscape ie wider width shots.
If you go for the Pentax I'd suggest the 645N rather than the Nii. No real difference to speak of and usually quite a bit cheaper. I have one and love it. I'm really happy with my set of MF cameras to be honest, a Pentax 645N with a few lenses, a Rolleicord Va, and a Fuji GW690III: it's a fairly comprehensive spread of styles and formats each with their strengths and weaknesses.
 
Only critical difference is later one has mirror lock up. Fortunately I hate tripods so that wouldn't be an issue ;)
 
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