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Rhys
03-26-2006, 04:00 PM
How do people find the Pentax *istD(all models) focus in a variety of light conditions?

How do people find Pentax lenses for quality (resolution, aberations, fringing, distortion etc)?

How do people find the AA batteries to be, in use?

jeisner
03-26-2006, 06:07 PM
How do people find the Pentax *istD(all models) focus in a variety of light conditions?

I find it does depend a bit on the lens, brighter lenses obviously more responsive than darker ones (in low light)...

I have compared to my friends 20d, and yes his camera is a bit faster (than the D), but at the expense of bigger and heavier lenses.. My pentax is fast enough for my needs, I am not a pro sports photographer and haven't missed shots that I can think of due to the slightly slower AF (which is mainly due to in body AF motor rather than in lens like c&n). I have both the DS and the D, the D is a little faster than the DS, I also find AF using CRV3 batteries more responsive than using NIMH AA rechargables... As far as I can tell the AF is very accurate in all light conditions (except with some Sigma lenses, but that is IMO Sigma's issue)..


How do people find Pentax lenses for quality (resolution, aberations, fringing, distortion etc)?

The lens quality is top notch in my experience, lighter/smaller generally due to the lack of in lens focus motor (and generally Pentax design principle of being small).. My DA 16-45 f4 compares very well against my friends Canon 17-45 f4, and is much lighter and almost half the price.. Pentax primes like the limited series are amongst the best available I think.. I am still saving for the 31mm ltd, but have used it and it is amazing...

http://www.luminous-landscape.com/columns/sm-02-05-02.shtml

I was also very pleasantly suprised with the DA 50-200 4-5.6 ED, it is absolutely tiny but amazing quality considering the range (both optical and price) its only slight issue is a little distortion at either end. Nothing serious and considering what an absolute gem it is in other respects, more than forgivable... I can rate all my lenses if you like ;-) but maybe you could ask about specific ones you are interested in?


How do people find the AA batteries to be, in use?

I generally use CRV3 batteries as they feel like they last for ever.. I am up to 898 photos (many with flash) with my current set, and expect a fair few hundred more.. 2500mah AA NIMH work OK too, I got maybe 300-400 photos from a set.. My problem with them is they flatten themselves even when not in use, although I think Sanyo has released some improved ones in the US (haven't seen them here yet)...

Ishkabibble
03-26-2006, 10:11 PM
I think one of the biggest influences of focus performance is the speed of your glass... faster glass = more light = better performance. Consider what you plan to spend on glass and whether you will use AF regularily. These two factors are essential; they directly impact low-light performance.

I would contend that the DS is slower to focus than cameras with AF assist lamps (assuming the same speed of glass). This said, I have found the performance more than ample. Also note that this is only an issue in low light scenes... like 1-4 candles.

This model strobes the flash instead of using an AF assist lamp. This drastically improves focus accuracy and speed, but I prefer not to use it... I avoid intrusions whenever possible.

Simple suggestions: If you don't regularily shoot in substandard light, the DS is a very pleasing unit; You need read no further.

If you shoot in substandard light occasionally, but consider substandard to be less than a point and shoot will handle, look at a room with 4 candles burning in it. Anything less than this and you'll need MUCH better glass. (you can still go lower in light with poor glass, but not for motion shots). Anything more than this and even the kit lens is acceptable (do not read optimal, faster glass would still be better). A dSLR is a good choice, Pentax included; plan on investing in faster glass at some point. Focal performance in this amount of light will be slow with the kit lens, and fast with fast glass.

Assuming you will shoot in substandard light regularily, decide if you will be using a flash. If you will, Pentax or almost any dSLR will focus well... so will some point and shoot models. Pentax simply strobes the flash and you get good, fast focus. If you plan on not using flash in low-light, you might be better to look for something with an AF assist lamp. You'd also best plan on investing considerable dollars into fast lenses; you'll get too much blurr without them.

Note: The tests above are crude at best, but should provide a general framework for understanding.

Ishkabibble
03-26-2006, 10:23 PM
I have found battery performance on Energizer 2500 cells to be ample. I shoot almost exclusively in RAW and have never managed to drain a set, even after shooting several hours. Still, I'd recommend two sets at an optimal power solution.

If you plan on extended times between charges, such as you might experience on a vacation, look to L-ion cells as a better solution, the CRV3 non-rechargable ones. They last an exceptionally long time.

Image quality is a function of the lens quality... buy junk and you'll get poor images. Pentax is known for exceptional lenses though, so if you don't simply buy the cheapest no-name cwap you can find, you should be relatively pleased. Also, this unit can leverage old glass very well... it's cheap and, if you know what you're doing, you'll get exceptional results.

Rhys
03-27-2006, 06:22 AM
What's the image quality like on non digital glass?

I don't have a Pentax, having a Canon myself but I'd love to know. I have seen some shots that Pentax users seem to think are good using old MF lenses that don't look at all good to me.

Ishkabibble
03-27-2006, 07:45 AM
Interesting approach... you are asking for opinions, but also openly stating you don't agree with many of the opinions you have read in the past. I fail to see how a few more of the same (opinions) will provide you with the confirmation you seek. You need to provide a frame of reference.

Precisely what are your expectations? Are we comparing against something tangible? If we are using a D2X as a base model, you'll see a dramatically different opinion than if we base opinions against a Rebel. If it is accuracy you are after, please give us a framework to guide our responses.

Images with non-digital glass can be impressive; they can also be atrocious. I consider it more a function of the photographer than the camera... we had amazing photography over 50 years ago, when none of this technology existed. Even the best camera, in the hands of the unskilled, won't produce much. It's less about the hardware and more about what you do with it.

There is another critical fact related to your question. Grouping all non-digital glass together isn't practical. There are vast ranges of quality in the category you provide. Some is exceptionally good and some is exceptionally bad. With hundreds, perhaps thousands, of lenses in the category you present, there isn't much we can tell you about generic quality from these lenses. I would suggest you look at lens reviews to get a better feel for what is available for the Pentax... start by looking for the 1.4 Super Takumar.

Lastly, my knowledge when I started in dSLR was poor. I didn't intimately understand the critical aspects of photography such as DOF, Bokeh... I didn't know the difference between various colorspaces... in short I knew squat. Using the hardware, I learned more. The images didn't look impressive until I knew what to look for in them. At the onset, some poor glass looked good and some good glass looked poor. I saw images people loved and I couldn't understand what the fuss was about... they didn't look that good to me. If you know what to look for in your images, that's great! But if you don't, give little weight to your personal opinion until you do. My opinions when I first moved into photography were way off the mark; it was only with reading, practice, and the development of skill that I learned why other photographers liked certain lenses and images.

Rhys
03-27-2006, 09:17 AM
Interesting approach... you are asking for opinions, but also openly stating you don't agree with many of the opinions you have read in the past. I fail to see how a few more of the same (opinions) will provide you with the confirmation you seek. You need to provide a frame of reference.

I'm looking at image quality, usability and practical use.

I currently have a Canon XT with a mix of Tamron and Canon lenses. I also have a Nikon MF outfit.

I find the focussing on the XT is poorer than I'd like and that the lack of a Canon focussing aid in it is a real bind - particularly in those situations when AF doesn't want to work. I could honestly do a better job myself and it's my long-held experience of AF that I can do it better manually.

I am drawn to the idea of AA batteries on the basis that I can thumb 4 AA batteries in from any source and have a working camera. It's also convenient because most AA chargers will charge 4 AA batteries. I can take batteries out of my hyperdrive, my flash or my camera and they'd all be the same. That, to me, is a huge bonus. Just one battery type to be concerned with and best of all I can walk into any store and buy alkaline/lithium AA batteries if I'm really stuck.

I was put off the Pentax initially as I had a Pentax Super A many years ago that gave nothing but problems and which I eventually sold about 9 months after I bought it because I was so sick of sending the damned thing back to the factory only for it to come back with another fault. That and the fact that nobody locally stocked one I could look at and that there were no other K-mount digital AF cameras at the time. At least Canon and Nikon had several models to choose from.

I'm happy with the image quality of my Canon. I wish Nikon had made it easier for me to use my existing Nikon MF lenses so that I didn't have to get a whole new system. I'm also happy with the fact that Canon has a full frame dSLR - which I can aim toward in a year or two.

I miss using manual focus lenses. I would love to use AA batteries. I don't feel that Haoda screen is a great investment nor the Katz screen. I don't feel the 6xAA option of the Canon grip is that great either. That's just too many AAs and the screens are too fiddly for me to want to bother with.

Ishkabibble
03-27-2006, 09:30 AM
I have to appolagize for the apparent rudeness in my last post. I just read it and realize that, though the points are valid, the wording came across wrong.

We do need a frame of reference from which to measure the DS performance though, and more direction on how you define non-digital glass.

Here's an absurd example of why we need a reference point:
Looking at the images of the DS along side of those from a Hasselblad with a P45 digital back, there is no doubt the Hasselblad produces superior results. Buy a Hasselblad and P45 digital back.

Clearly the cameras can't be directly compared... one is entry level and the other costs as much as a world cruise. But if your budget for a camera wasn't a limitation, and you had the experience to leverage a professional dSLR, you'd likely want the Hasselblad.

Put in the frame of optics... "the 50mm/1.4 Super Takumar failed on all our AF tests... clearly it is a poor lens." Expecting superior AF performance from a manual lens is literal insanity, but the point is that the same lens everyone raves about is not suited to photographers that won't manually focus. What are we reviewing... manual or auto... primes or multipurpose... fast or cheap... older MF or new digital... you get the point. We need to know what we are reviewing... and also, lenses fill purpose; we need to know your purpose to draw inferences on what your experience will be.

A guess regarding reference point, and some thoughts on it:

I took a look at some of your prior posts and note that you are using a Canon Rebel XT. This is known to have compatibility issues with older glass, especially Sigma glass. The Pentax compatibility is much greater than your current system in this respect. I have to be honest though, while I prefer the Pentax DS to your XT, I still think a switch would be more of a lateral move for you. If you are planning to move from the XT, you might want to look deeper in the lines.

Ishkabibble
03-27-2006, 10:01 AM
I'm looking at image quality, usability and practical use.

I currently have a Canon XT with a mix of Tamron and Canon lenses. I also have a Nikon MF outfit.

I find the focussing on the XT is poorer than I'd like and that the lack of a Canon focussing aid in it is a real bind - particularly in those situations when AF doesn't want to work. I could honestly do a better job myself and it's my long-held experience of AF that I can do it better manually.

I don't expect you'll find the Pentax much more effective in this respect. The DS lacks an AF assist lamp, so it isn't as accurate as you appear to want. I find the manual focus is superior to the AF... but please keep in mind that I haven't as considerable lens experience as some. There are good AF lenses with excellent focal performance... I just haven't owned them. I suspect there are also excellent AF lenses for your Canon.


I am drawn to the idea of AA batteries on the basis that I can thumb 4 AA batteries in from any source and have a working camera. It's also convenient because most AA chargers will charge 4 AA batteries. I can take batteries out of my hyperdrive, my flash or my camera and they'd all be the same. That, to me, is a huge bonus. Just one battery type to be concerned with and best of all I can walk into any store and buy alkaline/lithium AA batteries if I'm really stuck.

This is one of the things I most love about the DS. You'll be pleased with the battery aspect of this camera.


I was put off the Pentax initially as I had a Pentax Super A many years ago that gave nothing but problems and which I eventually sold about 9 months after I bought it because I was so sick of sending the damned thing back to the factory only for it to come back with another fault. That and the fact that nobody locally stocked one I could look at and that there were no other K-mount digital AF cameras at the time. At least Canon and Nikon had several models to choose from.

Good reasons. I've had great luck with my Pentax; so have most of the people who've posted on this forum. There have been a couple of issues though... not sure what happened to one poster from a few months back. My nutshell assessment is that the cameras are good... the service isn't.


I'm happy with the image quality of my Canon. I wish Nikon had made it easier for me to use my existing Nikon MF lenses so that I didn't have to get a whole new system. I'm also happy with the fact that Canon has a full frame dSLR - which I can aim toward in a year or two.

Lens compatibility is one place the DS shines. But don't consider the Pentax if you are going to a full-frame Canon in a couple years... you want to be able to continue your lens investments into the future. Pentax is coming out with a pro dSLR shortly... perhaps you should read about it and confirm where you are heading... then buy a camera that fits your long-term path.


I miss using manual focus lenses. I would love to use AA batteries. I don't feel that Haoda screen is a great investment nor the Katz screen. I don't feel the 6xAA option of the Canon grip is that great either. That's just too many AAs and the screens are too fiddly for me to want to bother with.

You seem to be looking to step beyond the limitations of your XT. I'm not surprised, but I think you will still find the Pentax D line isn't enough of a step up to warrant the expendature. I would save your G-note(s with lenses) and apply it to your full frame dSLR purchase. The DS is a great unit, but if you are simply looking for a temporary transition unit, your money can be better spent.

Rhys
03-27-2006, 01:25 PM
I suspect you're right about my wanting to step up from the limitations of my XT. I did consider the Pentax but couldn't take that further because I couldn't get my hands on one. Similarly, I couldn't check the Olympus because the only one I could find (E-300) was a broken display model in Sam's Club.

I just looked at the next model up in the Canon range - the 30D. That doesn't have interchangable focussing screens either. The 1D2 does, however, cost between $3000 and $6000 depending on version - according to pricegrabber.

Currently all but my 18-55 kit lens will fit on the 1D. I guess if I sold all my Canon kit to finance a Pentax I'd probably take a hit of about 1k. I guess I bought an amateur camera instead of a pro camera when I'm used to pro cameras with my Nikon background. I used to use a pair of Nikon FMs with motordrives, hammerhead flashgun and prime lenses of 28,35,50,85,135,200,300 lengths plus tubes and 2xTC. That covered me for all situations until Nikon decided to make life difficult for AIS lens users when they brought in their dSLRs.

Looks to me like I could be better getting a 1DSmk2.

Ishkabibble
03-27-2006, 09:23 PM
I have used it's predicessor, the 1Ds. Now there's a horse of a different colour. Until the Mark II was released, I considered the 1Ds the camera to beat... and the Mark II did just that. There is no question in my mind that either the 1Ds or the Mark II will be the step up you are looking for... with plenty of room to grow.

If you can afford one of those two units, there is little else worthy of consideration.

PS. Check eBay auctions for a listing of the older 1Ds if it will fulfill your needs... I've seen a couple at pretty agressive prices.

astro
03-28-2006, 10:09 PM
I have seen some shots that Pentax users seem to think are good using old MF lenses that don't look at all good to me.

Really? What do you think about these shots I took?
http://www.dcresource.com/forums/showthread.php?t=16900