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01-01-2010, 04:13 PM   #31
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QuoteOriginally posted by ryan s Quote
The part I bolded...how many film cameras are being built today? Leica and Rollei and company are about the only ones. Holga, I guess
Ummm:
  • Arca-Swiss
  • Canon
  • Hasselblad
  • Horseman
  • Leica
  • Linhoff
  • Mamiya
  • Nikon
  • Phase One
  • Rollei
  • Seagull
  • Toyo
  • Vivitar
  • Voigtlander
  • Wista
  • Zeiss
And others...

01-01-2010, 04:54 PM   #32
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QuoteOriginally posted by Just1MoreDave Quote
Now that I read it again, it needs some qualifications. I was thinking of two points that don't apply to every lens or camera combination.

First, the aperture rings rarely click at every possible half-stop, so using just the aperture ring, you sometimes will not have a setting where you need it. I'll agree that a 20 year old A50/2 only dropped twice may not hit every third-stop between f2 and f2.8 with perfect accuracy, but the ring only clicks at each full stop. If you want f2.4, the camera body can probably do that at least as well as trying to put the ring between clicks. On many lenses, the ring clicks at an unmarked position - e. g. the M50/1.7 clicks between f1.7 and f2.8 (probably f2). An A lens doesn't have that ambiguity.

Second, on a crippled-mount body, the lenses with an A position work like they were designed to in the A position. That is, having the aperture adjusted by the lever. Once you go off that A position, the mechanism within the lens is used. It is probably more a feeling than fact that these may produce different results. I haven't tested it myself. If you're not using a crippled-mount body, it probably doesn't matter as much.

I think the statement would be harder to defend if I had not included the qualifier phrase "between lenses". That's where the first point can be important. On the lens tests I've done, I always find some lenses without a setting at certain apertures. But if I had a lot more "A"-type lenses, I might be complaining about the false impression of accuracy given by the viewfinder numbers.
Thanks for the clarification. This answer makes more sense. I hope you don't mind that I bolded the last sentence.

I was taught that process accuracy is how close the delivered value is to that which was expected. Precision is the variance around that value for multiple attempts. I would expect that aperture accuracy might vary between lenses, even for the same model based on care taken at time of manufacture. Precision is determined by a combination of design, build quality, and wear from usage.

With an "A" lens, aperture lever travel is supposed to be proportional to the aperture area. X amount of travel will result in Y percentage increase/decrease in aperture. Given that the amount of travel is never more than about 6 mm full open to full closed, it is amazing that these things work at all, never mind to 1/3 stop increments. Factor in the required manufacturing tolerances to translate that motion through a system of levers and rings with no run-time feedback mechanism...I think you can get my drift. Both accuracy and precision are difficult to attain and are the product of both body and lens build quality.

Compare that to the traditional aperture ring with fairly large movements that translate the setting through fairly simple mechanisms and mechanical detents.

Now as far as performance of an Pentax-A series lens both on and off the "A" setting... The aperture ring on my A 50/1.7 is so clunky, I don't think I would use it on any of my pre-A bodies! Assuming it works correctly, my understanding is that the aperture lever executes full motion for lenses off the "A" setting with the aperture being determined by the mechanical "stop" for the ring position. When in the "A" position, there is no stop (i.e. minimum aperture). Same mechanism for both methods with different means to determine when the blades stop. Accuracy and precision for this case is also determined by build quality, though the task is somewhat easier and extends to the lens only.

Thankfully, both film and digital sensors have plenty of exposure latitude!

Steve
01-01-2010, 05:18 PM   #33
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Any Pentax body that supports Programmed AE or Shutter Preferred AE can be used successfully with lenses that don't have an aperture ring.
Any of the Pentax film bodies that support aperture adjustment from the body can fully utilize lenses that are missing the aperture ring.
01-03-2010, 01:43 PM   #34
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Sorry for the late reply and Happy New Year!

QuoteOriginally posted by Lowell Goudge Quote
the crippled mount has nothing to do with the camera body setting aperture.

the crippled mount only prohibits the use of Av mode through setting of th elens due to lack of the aperture setting on th ering which was removed when they crippled the mount.
As far as I know the crippling removed the mechanical sensor that figures out what aperture you have set on the lens - that's why you can't use K/M lenses in Av mode. The camera doesn't know your aperture setting so it can't calculate the exposure - I assume it usually takes a reading wide open and then, knowing the set aperture, it figures out the exposure time for that aperture. But because it can't tell the aperture setting, you have to use the green button in M mode and force a stopped down reading.

See the Wikipedia article:

QuoteOriginally posted by wikipedia:
Like the "crippled" KAF mount, it does not have a mechanical stop-down coupler/indicator and thus can only use stop-down metering on pre-A lenses.


01-03-2010, 08:53 PM   #35
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I much prefer on body aperture control, which is why I still have my ZX-L and sold my MZ-S.

The Pentax DSLR's still take great pictures with non 'A' lenses. Just check out the Takumar Club, The K-Club and The M Club.
01-03-2010, 09:41 PM   #36
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QuoteOriginally posted by stevebrot Quote
I have large hands and even on the honking big K10D my thumb overshoots the rear wheel. The aperture ring on my tiny film cameras is much easier to use!

Steve
Try using a grip. Works for me. I have the genuine one, but I suspect anything that gives you a taller grip on the right side will work.
01-03-2010, 10:31 PM   #37
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QuoteOriginally posted by Canada_Rockies Quote
Try using a grip. Works for me. I have the genuine one, but I suspect anything that gives you a taller grip on the right side will work.
That is an excellent suggestion. I tried the K-7 at the traveling road show this last summer and was amazed at the difference the grip made with that camera.

Steve
01-05-2010, 10:56 PM   #38
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QuoteOriginally posted by keyser Quote
If pentax had continued to offer an aperture ring, they could have offered a simple dSLR that mirrors the simplicity of film. On the left shoulder of the camera you would set your ISO to a specific value, or auto. On your right shoulder you do the same with shutter speed. Finally you set your aperture on the lens.
According to your profile you own:

QuoteQuote:
Canon rebel XS
Canon EF-S 18-55mm f/3.5-5.6
Canon EF 75-300mm f/4-5.6 USM
Isn't the Rebel XS a dSLR? I own a Rebel XT, and find the current trend toward removing compatibility disappointing, but Pentax is hardly the original offender of the trend. I believe Canon was the first offender back in the 80's. None of my EF mount lenses had aperture rings. It seems to be the state of photography today.

I agree though, it's unfortunate.

01-06-2010, 12:02 AM   #39
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QuoteOriginally posted by jadedrakerider Quote
I believe Canon was the first offender back in the 80's. None of my EF mount lenses had aperture rings. It seems to be the state of photography today.

I agree though, it's unfortunate.
From Canon, we expect this sort of thing. One would think that Pentax would not have gone that direction.

I keep hoping that Zeiss or Cosina will offer a simplified, pro-level, FF dSLR.

Steve
01-06-2010, 01:21 PM   #40
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QuoteOriginally posted by stevebrot Quote
I keep hoping that Zeiss or Cosina will offer a simplified, pro-level, FF dSLR.

Steve
Much, much money though... Just imagine how much this thing would cost! Although, I'd love a camera at least on par with KM 7D. I loved all those levels and buttons...
01-07-2010, 01:07 PM   #41
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QuoteOriginally posted by stevebrot Quote
Ummm:
  • Arca-Swiss
  • Canon
  • Hasselblad
  • Horseman
  • Leica
  • Linhoff
  • Mamiya
  • Nikon
  • Phase One
  • Rollei
  • Seagull
  • Toyo
  • Vivitar
  • Voigtlander
  • Wista
  • Zeiss
And others...
Anything for say...under $100? Besides the Vivitars and Seagulls.
01-07-2010, 05:48 PM   #42
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QuoteOriginally posted by ryan s Quote
Anything for say...under $100? Besides the Vivitars and Seagulls.
Nope...Those are film cameras of reasonable quality that are available new in the current market. Some of them are quite expensive. If you want cheap...think Holga!

Steve
12-13-2012, 05:41 PM   #43
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I use my same lens on the K-7 and on my film MZ-S film camera. In fact, the silver 77mm limited and the smaller 43mm limited work very well indeed, and actually look kind of cool on the MZ-S body. It would look even cooler if someone would sell me their BG-10 battery grip to go on the MZ-S body.
12-19-2012, 11:53 PM   #44
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I cannot stand most modern lenses that do not have aperture rings - the DA15mm f/4 wouldn't really gain much from one in the first place since one of the best points about having an aperture rings is the engraved DOF scales on the lenses which is somewhat redundant on the DA15 f/4 because the DOF from that lens is so deep at f11 almost everything from 1m to infinity will be sharp enough.

QuoteOriginally posted by stevebrot Quote
What could possibly be next...carbon printing?
I hate to burst your bubble but you need an exceptionally good darkroom to do carbon printing well....one thing I wish would happen would be a return of dye transfer printing, the best way to get a 500:1 contrast ratio on paper. I would like to see Epson "HDR" inks accomplish that.
12-20-2012, 01:58 AM - 1 Like   #45
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QuoteOriginally posted by keyser Quote
It's been said many time that camera companies make their money selling lenses, not bodies. Why then, do they insist on producing a whole generation of lenses that for various reasons can't be used properly on any film camera?
Maybe because their business model is quite logically targeted more towards getting you to buy a DSLR than it is towards helping you use a film camera. Pentax has to sell lots of new DSLR's to stay in business, bottom line. They want legacy users to be able to use their old lenses on DSLR's because it's a good selling point, the fact that you don't have to buy a whole new kit of lenses to use your new camera right away. They want you to, sure, but at least they've got you using a new digital body and hopefully at least a kit lens to start and they hope of course that you will like the convenience of digital and auto focus lenses and that accordingly your digital lens kit will grow over time. But if you continue to use an old film body it's not something that really helps their profit margin as much. It all boils down to the fact that they have to transition you from film to digital to keep you buying more.

It makes sense. As much as I love using my film SLR's I have to work far harder to get film developed here anymore. Most of the places that did it have stopped. About the only place I can get film developed here outside a professional lab that charges accordingly is Walgreens and there is talk that they are going to stop next year as most other stores already have. I can get digital prints made all over town if I want though. Even if I had the room, which I don't, getting the chemicals to process film would be cost prohibitive for me as I'd probably have to order them online. Not to mention I'd have to buy a tank and tons of other things to do the job and that's just for B&W. Of course color is even more complicated...

There was a time when many pros out there were more against the use of digital than not. Many of them clung to film like they were on a sinking ship and every last can of film they could get their hands on was their lifeboat. Now using digital is common even in fields where photographer totally disdained it and the full on use of film is more often than not the exception and not the rule. Diehard film lovers or not as digital cameras got better more and more pros transitioned to them. Though some do use film or both, a majority of photographers use digital now ergo the market is aimed squarely at digital shooters. They buy more they are the priority. They want the business of film shooters too, but it's not nearly as important to them as getting the business of the digital shooters.

Film users at this point are a niche market. It's a niche market that is surprisingly holding it's own of late and that is even attracting some younger users but it's still a niche market. Digital is 95% of the market these days. Who are you going to cater to if that's the case? The 95% or the 5%? Logically of course you're going to manufacture for the majority market and unfortunately that's not the people who would likely put a digital lens on an older FF body. If Pentax made a FF camera that would likely lead to the making of lenses that would work better on old bodies, but for right now it seems they're not really all that interested in going there, in reworking most of their lenses for FF when most of what they sell is stuff made for digital cameras with a smaller sensor. Again it all comes down to what the majority of their market is buying which is not actually FF cameras.

In the end it comes down to how much it costs to make a FF body and to upgrade those lenses vs how many people they might actually sell the FF gear to. Looking at other camera makers and seeing how their FF stuff is doing I think they'd sell a decent amount of FF gear but would they sell enough to actually make it cost effective to produce it regularly? I'm honestly not too sure of that.
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