[Anvh]

Screw-driven focus is a proven concept. I don't understand what all the fuss is about. I don't want Pentax developing SDM because I can't yet see a benefit. Maybe if speed increases substantially, but I couldn't care less about noise. Personally, noise from the screw has never ruined a shot for me and I've never had focusing problems from a screw-driven lens. SDM on the other hand is a different story.

I can give you a good reason, possibility for less mechanical parts and better AF because part of the AF system can be precisely fine tuned for the lens.
Problem is Pentax used the KAF2 mount for lenses with most DA* so it actually added parts and making the system more complicated now that they have said to either do screw-drive or build-in motor things will most likely improve.

From the latest sruvey here about SDM failures it's quite simple to make a list.
Most problems so avoid them if you don't want to take risk
- DA*16-50
- DA*50-135
- DA17-70

Lenses of which have no failures or a very small percentage.
- DA*55
- DA*200
- DA*300
- DA*60-250

I can surely understand why you would avoid the DA*16-50 or DA*50-135 since they surely have some problems but there is no reason to avoid the DA* prime lenses for example.

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Last edited by Anvh; 06-28-2012 at 11:19 AM.

[pinholecam]

Screw-driven focus is a proven concept. I don't understand what all the fuss is about. I don't want Pentax developing SDM because I can't yet see a benefit. Maybe if speed increases substantially, but I couldn't care less about noise. Personally, noise from the screw has never ruined a shot for me and I've never had focusing problems from a screw-driven lens. SDM on the other hand is a different story.

It may be correct the problem isn't as big now, but I won't be buying another SDM. That's part of the problem; I don't have more current data because it's not worth the risk to me. I don't think I'm the only one avoiding SDM, which is unfortunate because I'd love to try the 55, 50-135 and 60-250.

Maybe if Pentax finally releases a FF I'd be willing to try another SDM lens. That way I'll have a mcuh better viewfinder to manually focus if the SDM dies.

I agree than screw drive is a proven concept. In fact for lenses to be usable/viable over many years, I still think its the better method.

However, its also a follow or die situation as competitors move to the 'latest and greatest' (even if untrue) and Pentax can be seen as incompetent by the layman and future buyer.
The main advantage of SDM would be silent AF for video.

Already, I've seen many comments by newbies in the local forums that when they try a Pentax, they find that the AF is 'noisy' (ie. in a way hinting their impression of technical incompetence compared to Canikony)

[Na Horuk]

Honestly, I would rather see them improve the screw drive AF to make it more silent and faster, rather than making a bunch of lenses with motors. A lens without a motor can be used for decades, but a lens with a motor can have all sort of problems.

[eddie1960]

Honestly, I would rather see them improve the screw drive AF to make it more silent and faster, rather than making a bunch of lenses with motors. A lens without a motor can be used for decades, but a lens with a motor can have all sort of problems.

I agree, and likely they can make them a little more silent (and in fact the same thing may also end up improving the WR more seals and such will dampen noise. one of the reason screw drive seems noisier now is the speed it is operating at to compete.
Personally i have no issue with screw drive though a little quieter would be nice, and would use MF for video anyway so no screw drive noise there
I doubt any of the SDM variant lenses from everyone will last like a Tak has though for example. Over on the Takumar club Asahiflex commented that his taks would go to the grave with him and he wouldn't be surprised to see them usable after being dug up a millennia from now I tend to agree.

[Anvh]

Honestly, I would rather see them improve the screw drive AF to make it more silent and faster, rather than making a bunch of lenses with motors. A lens without a motor can be used for decades, but a lens with a motor can have all sort of problems.

But less can improve with that and also you will always need a bigger engine in the camera because of the lost of power by the linkages.

About in lens motor and how long the lens last i wouldnt worry about that for a sec, with 3 or 4 screws you've access to the motor so see it as part of the maintenance.
Besides the gears and shafts needed for the AF with screw-drive also wear and replacing those is less easy.

[builttospill]

Honestly, I would rather see them improve the screw drive AF to make it more silent and faster, rather than making a bunch of lenses with motors. A lens without a motor can be used for decades, but a lens with a motor can have all sort of problems.

Not a bad option, but for discussion, as well as fitting my shooting style, I'd take a slower focusing screw-driven lens if Pentax could improve focus accuracy. I'd also like a few more focus points in the VF. None of this focus and recompose garbage. The center focus point is accurate enough, but I want the other points to be just as accurate.

[builttospill]

But less can improve with that and also you will always need a bigger engine in the camera because of the lost of power by the linkages.

About in lens motor and how long the lens last i wouldnt worry about that for a sec, with 3 or 4 screws you've access to the motor so see it as part of the maintenance.
Besides the gears and shafts needed for the AF with screw-drive also wear and replacing those is less easy.

But I've never had to replace those. I've had to have SDM replaced. Even more than that though, I'd hate to pay for a premium lens and have it fail. Removing a few screws to see a dead or jammed SDM isn't maintenance. Changing the oil or tires in a car is maintenance, but I won't buy a new car where I have to take a few screws out to see if the motor is dead or jammed. The cost of SDM lenses should ensure quality, both in images and build/durability.

[Mareket]

On a side note (related to FF) can someone tell me why everyone said the D800 is competing with medium format because it's 36MP? Why did no one say APS-C is competing with FF when the A77 came out? Or that M43 was competing with APS-C when the 16MP sensors came out? Or that the Q is competing with the K-x?

I get that it's an amazing camera, but everyone says FF wins over APS-C because of the larger sensor despite the IQ of each. Why doesn't the same apply for FF vs MF?

[Anvh]

But I've never had to replace those. I've had to have SDM replaced. Even more than that though, I'd hate to pay for a premium lens and have it fail. Removing a few screws to see a dead or jammed SDM isn't maintenance. Changing the oil or tires in a car is maintenance, but I won't buy a new car where I have to take a few screws out to see if the motor is dead or jammed. The cost of SDM lenses should ensure quality, both in images and build/durability.

Preciesly, it's a failed product the lens you had but don't draw the conclusion it's the same for all SDM lenses.

If i had one off my screw-drive lenses fail, it would also be silly to then say that all screw-drive focusing s*cks right....

So come on give it a break and come with something new.

[eddie1960]

On a side note (related to FF) can someone tell me why everyone said the D800 is competing with medium format because it's 36MP? Why did no one say APS-C is competing with FF when the A77 came out? Or that M43 was competing with APS-C when the 16MP sensors came out? Or that the Q is competing with the K-x?

I get that it's an amazing camera, but everyone says FF wins over APS-C because of the larger sensor despite the IQ of each. Why doesn't the same apply for FF vs MF?

the D800 is kind of unique in that it is beating the medium format cams in almost all categories (colour depth, Dynamic range, and iso performance. this reduces the MF advantage a bit. MF advantage in good light landscape or studio at the 40 mp size will be in how ell it prints large due to the larger pixels at close to the same resolution. This comes at a very large price premium. Step it up to a FF MF like the iQ 180 from Phase and the phase will have better colour depth, but still lower DR and much lower iso range (not important for it's use anyway) Of course it costs close to 10X as much for a base system with it. and it's largely a studio machine, but it can print larger without reducing resolution. at 300dpi the iq180 will print 35x26, the D800E will print 25x16 at the same res. Both can print to substantially larger than this of course while still remaining sharp at optimal distances for the print size. I've seen D800 printed at 6 ft on the long edge and it looked very good (even up close - wort of the ultimate pixel peep)

they are sucjh completely different target market cameras though it is irrelevant that the D800 will compete with Medium format. Medium format has always been a specialty market, the DSLR a generalist market. the biggest difference is now their is a FF that can provide results close to MEdium format (and better in many ways where you wouldn't use MF anyway - high iso meh who cares in MF, I would never take a MF to shoot a low light event or sports anyway)

[Chex]

The Q sort-of tries to compete, as do all the Micro 4/3 camera's do try competing with APS-C camera's.. and they are doing an ok job.. using the same argument that people use for APS-C over FF.. smaller, lighter, cheaper(generally). For the most part other than low light performance Micro 4/3 camera's are great performers.. I am perfectly ok with packing around my D800 in any event, even if I get the looks from others like "overkill for shooting your kindergartner's end of school celebration/graduation".. doesn't bother me in the least. But a Micro 4/3 or even a K-r with an FA77 Ltd would do just fine.

[Mareket]

Yarr, I just found it a tad perplexing that people were ignoring the advantage of a MF sensor. Understandably the difference in size and the ecosystem is the big thing, but the K-5 has better colour depth and dynamic range than a 5DMkII, and yet people don't say the K-5 makes the 5DMkII too expensive for the IQ gain of a larger sensor, despite the fact that it's twice the price or more.

I guess it just irritated me that the elevated status FF holds over APS-C isn't the same between MF and FF.

The Q sort-of tries to compete, as do all the Micro 4/3 camera's do try competing with APS-C camera's.. and they are doing an ok job..

Yarr, but people would buy APS-C over those for the bigger sensor right? Because bigger sensor = more light = better picture. But only until you get to FF. And no one proclaimed that the Q or M43 cameras are making APS-C obsolete because of their megapickles.

I do think the D800 is an amazing camera, it just seems to be (along with the X-Pro 1) the new child everyone is gushing over far more than is necessary. And yeah, you've demonstrated the point that choosing equipment doesn't have anything to do with what you need, it's to do with what you want. If you just buy what you need it takes a lot of the fun out of it. As with basically everything in life.

[eddie1960]

Yarr, I just found it a tad perplexing that people were ignoring the advantage of a MF sensor. Understandably the difference in size and the ecosystem is the big thing, but the K-5 has better colour depth and dynamic range than a 5DMkII, and yet people don't say the K-5 makes the 5DMkII too expensive for the IQ gain of a larger sensor, despite the fact that it's twice the price or more.

I guess it just irritated me that the elevated status FF holds over APS-C isn't the same between MF and FF.



Yarr, but people would buy APS-C over those for the bigger sensor right? Because bigger sensor = more light = better picture. But only until you get to FF. And no one proclaimed that the Q or M43 cameras are making APS-C obsolete because of their megapickles.

I do think the D800 is an amazing camera, it just seems to be (along with the X-Pro 1) the new child everyone is gushing over far more than is necessary. And yeah, you've demonstrated the point that choosing equipment doesn't have anything to do with what you need, it's to do with what you want. If you just buy what you need it takes a lot of the fun out of it. As with basically everything in life.

I'm not gushing over the Xpro1 - too many limitations for what it purports to be. the focus by wire system is not good for street photography which is where I saw it shining (like a true RF) no focus peaking for manual lenses so an m adapter is limited value
they do have a few nice looking lenses on the map and a mk 2 body may address some issues. Colour quality is very nice though. To be honest i'd rather have a K5 with the 15/21/40/70 DA LTD lenses for the same price as the Xpro with the 3 lenses. Better AF, Better high ISO, and all 4 lenses are excellent slight size weight penalty

[builttospill]

Preciesly, it's a failed product the lens you had but don't draw the conclusion it's the same for all SDM lenses.

If i had one off my screw-drive lenses fail, it would also be silly to then say that all screw-drive focusing s*cks right....

So come on give it a break and come with something new.

I feel like it's getting time to give it a break, but I wanted to clarify my response for you first. I believe both of us, along with many others here want something better than SDM (faster, more reliable...) so we're probably on the same page there. However, I did draw the conclusion it's the same for all SDM lenses because it's the same equipment. I've seen the survey stats here and I know some SDM lenses fare better than others. I don't put DC and SDM lenses into the same category together because it's a different motor, different parts, different system. SDM is SDM, DC is DC. If multiple SDM lenses fail, then I draw the conclusion there's a problem with SDM (see my next point).

You're right about it being silly to make a blanket statement like all screw-drive lenses suck because of one lens. The part I'd like to clarify is it was more than one lens, and even one in particular I owned had the entire SDM assembly replaced twice due to two failures. So even when the lens came "with something new" it didn't take long to fail again. Add that to all the others here complaining about problems and I feel I'm a little more justified in arriving at the conclusion I did.

I'll repeat I'm guessing we'd both like to see some improvement, both in focusing ability and Pentax carrying a camera with a larger sensor. I'm not trying to ruffle any feathers here. I just expect the premium products I use, as a customer, to last a long time. If they don't last, I wouldn't be a smart consumer purchasing more of them instead of considering other, more reliable and durable options.

[Mareket]

I'm not gushing over the Xpro1 - too many limitations for what it purports to be. the focus by wire system is not good for street photography which is where I saw it shining (like a true RF) no focus peaking for manual lenses so an m adapter is limited value
they do have a few nice looking lenses on the map and a mk 2 body may address some issues. Colour quality is very nice though. To be honest i'd rather have a K5 with the 15/21/40/70 DA LTD lenses for the same price as the Xpro with the 3 lenses. Better AF, Better high ISO, and all 4 lenses are excellent slight size weight penalty

No I know, I wasn't having a dig at you. Just the internet. The X-Pro 1 looks beautiful and you can get some awesome shots from it according to what I've heard. But the AF is dodgy, MF sucks, the focus scale is apparently wrong and focus by wire isn't particularly nice. So it's a great camera that's a pain to focus in every way :/

I reckon we Pentaxians have it good. Smaller cameras are selling well because people either want a small camera or because they have a big body and want a small one to complement it. The K-5's small anyway, so we just grab the Limiteds and be done with it Ain't no three lens system that gets much smaller than a K-5 + DA21/40/70 with comparable quality.

Also, dear god I want a Limited.