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Forum: Pentax SLR Lens Discussion 10-25-2017, 12:29 PM  
Someone here who's still using the oldest sigma 70-200 (APO EX (1999)) ?
Posted By nater
Replies: 12
Views: 671
Here's the thread in question detailing the issues with Sigma 100-300mm f/4 EX and the accounts of fixes by Sigma service:

Sigma 100-300 autofocus problem - PentaxForums.com
Forum: Pentax SLR Lens Discussion 10-17-2017, 02:30 PM  
Someone here who's still using the oldest sigma 70-200 (APO EX (1999)) ?
Posted By nater
Replies: 12
Views: 671
Wow, I got involved in these forums when I bought my K200D, and didn't know any of that about the Sigma 70-200mm f/2.8 EX lens and the *istD. In fact, when I read up on AF 70-200mm f/2.8 lenses for K-mount, there was a consensus that the original Sigma EX (not any of the later variants) was the best in terms of sharpness, and then I spent years on the lookout for a mint condition one for a good price until I finally found one. By that time, I had a K-5 (which is still my current body), and I've had no problems with the Sigma 70-200mm f/2.8 EX. I also picked up the Sigma 1.4X EX APO teleconverter, and had excellent results with that combo on the K-5. Just to make sure I'm not mis-remembering, I just did some impromptu test shots and had no trouble at f/2.8 at a variety of focal lengths focussing both through the lens and using live view on my K-5. In case it's a factor, my lens serial number is 2002539.

(Note that there are known issues with other EX Sigma lenses on current K-mount bodies, both the pre-DG 100-300mm f/4 EX and the early revisions of the 50-200mm f/2.8 EX DC.)
Forum: Travel, Events, and Groups 05-21-2017, 05:31 AM  
Rhode Island Air Show
Posted By nater
Replies: 0
Views: 472
Apologies if anyone has posted a thread already, but I thought I'd check to see if any other Pentaxians are at the RI Air Show this weekend. Should be a great day for it today!
Forum: Pentax SLR Lens Discussion 05-04-2017, 02:52 PM  
Pentax K-1 and Sigma 50mm f/1.4 lens
Posted By nater
Replies: 4
Views: 879
Sigma offers a service where they will replace the lens mount with one that will not scratch the K-1. Details are here:

News update for Pentax K-1 Users with Pentax mount SIGMA lenses | Sigma Corporation of America
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 05-04-2017, 11:52 AM  
Sony A9 Officially Announced Today
Posted By nater
Replies: 552
Views: 22,072
I think one of the things nobody has mentioned is that there are things like Sigma's MC-11 Mount converter, which will adapt Sigma's Canon EF-mount lenses to Sony E-mount. Currently selling for $150:

Sigma MC-11 Mount Converter/Lens Adapter 89E965 B&H Photo Video

For folks who already have a significant number of Sigma EF-mount lenses, I can see the appeal of this adapter with a Sony A9. Makes the whole "Sony doesn't have enough lenses" argument somewhat moot.
Forum: Pentax Price Watch 12-10-2016, 09:34 AM  
Ancient Sigma 70-210mm f/2.8 AF lens in questionable condition
Posted By nater
Replies: 1
Views: 578
This lot has been on ebay unsold for a while (relisted recently), no relation to the seller:

Lot of 4 Lenses Pentax , Tokina, Vivitar , Sigma #16E374 | eBay

$115 for all four shipped in the US might be a good deal, depending on the actual condition of the lenses (glass condition, haze, etc.) The Sigma 70-210mm is a constant f/2.8 (with a massive 82mm front filter size, and with a filter fitted to it, front glass might be in good condition). This Sigma AF lens predates the EX and EX DG lineup by a few years, so we're talking early '90s era. Who knows if AF works on modern bodies. It's missing the tripod collar and hood, and the body has been through a lot as it's missing a lot of the text, in fact the seller erroneously calls the lens an "AF700" where the text originally read "AF ZOOM APO" but the bottom of the Z wore off, the M wore off, and the APO wore off! So who knows what you'd get, but I thought it was worth mentioning here.
Forum: Pentax Price Watch 11-22-2016, 11:51 PM  
Rokinon 135mm f/2.0 for $399 at Amazon
Posted By nater
Replies: 1
Views: 468
Forum: Pentax DSLR Discussion 09-08-2016, 10:16 AM  
Two hypothetical future bodies I'd like to see..
Posted By nater
Replies: 28
Views: 5,345
Looks like there is now a wider realization of my second idea that cameras need to be software platforms, Tony Northrup talks about it quite a bit in "The DEATH of the Consumer Camera":
















You Tube




If people here are interested, maybe we can put together a public petition to Ricoh/Pentax to evolve the Pentax camera platform.
Forum: Pentax Price Watch 08-04-2016, 07:53 PM  
Back up ur truck & get ur K-1 from jet.com - $1731.06 to $1796.95 & 15% off
Posted By nater
Replies: 10
Views: 772
I bought some Corsair RAM from Jet.com and it came from Newegg. I opted to not do the free returns because Corsair RAM has a lifetime warranty... however out of the box only three of the four sticks would work in my quad-channel system (any three, didn't matter which ones). I knew it wasn't my motherboard because I had a quad channel set (different brand) that worked fine. When I contacted Corsair they gave me nothing but a hard time because it was bought from Jet.com and they didn't recognize them as an authorized reseller of Corsair products. It took over a week of back and forth with Corsair before they finally accepted it for RMA replacement. The replacement sticks work fine, but I'm hesitant to order from Jet.com again and I didn't like dealing with Corsair support (other companies like Kingston and Crucial are much easier to work with on memory RMAs).
Forum: Pentax K-1 06-27-2016, 11:24 AM  
Sigma Damage to K-1
Posted By nater
Replies: 36
Views: 3,069
Thank you for confirming what I had inferred/expected. I'll be very happy if my efforts to avoid owning any HSM lenses work out well in the end with regards to the K-1.
Forum: Pentax K-1 06-26-2016, 07:20 PM  
Sigma Damage to K-1
Posted By nater
Replies: 36
Views: 3,069
I haven't bought a K-1 yet, but plan to. I own a number of pre-HSM (EX and EX DG) Sigma lenses, and they all have aperture rings. I wrote to Sigma asking them if they either knew if they were compatible and if they had any plans to to offer a repair service for those lenses. Their response was, "As after service period for some models have been expired already, we haven't checked for those model." Does anyone have any experience with pre-HSM Sigma EX and EX DG lenses on the K-1?
Forum: Pentax Full Frame 02-19-2016, 07:17 PM  
Which legacy Pentax lenses have corrections built in to the K-1?
Posted By nater
Replies: 30
Views: 2,416
Correct me if I'm wrong, but the lens profiles only matter if you shoot in JPEG. If you're shooting RAW, you apply the lens corrections in your RAW developer software. (I only shoot RAW, so this feature doesn't matter much to me for instance.)
Forum: Pentax SLR Lens Discussion 12-15-2015, 09:05 PM  
prime, prime, everywhere a prime...
Posted By nater
Replies: 2,421
Views: 155,781
I've owned a lot of zooms over the years. Mostly use the longer ones at air shows. Currently have the Pentax 55-300, Sigma 70-200mm f2.8 (first AF version), Sigma 1.5x teleconverter, Sigma 50-500mm (first version). Owned the Tokina 80-400mm, loved the build and the size but quality at 400mm wasn't great (also owned the Tokina 400mm f5.6 AF but found the lack of zoom too limiting). Also owned the Sigma 135-400mm, found the range too limiting. The first Sigma 50-500mm is good at 400mm (better than the later version actually) and I've been happy with it. Good zoom range, and good quality at the focal lengths I care about.
Forum: Pentax SLR Lens Discussion 11-19-2015, 11:27 PM  
Where do decentered lenses end up?
Posted By nater
Replies: 18
Views: 2,439
Forum: Sold Items 08-22-2015, 07:44 PM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Thanks for all the good transactions with everyone, the rest is going to ebay. In case anyone is interested, you'll find the items listed there in the near future: nater890 | eBay
Forum: Sold Items 08-20-2015, 02:55 AM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Vivitar Series 1 35mm f1.4. This lens is by Samyang, and is one of the best 35mm lenses you can buy. Manual focus with an aperture you can control by the camera body. Here is a review of the optical quality: Samyang 35 mm f/1.4 AS UMC review - Introduction - Lenstip.com
Forum: Sold Items 08-20-2015, 02:48 AM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Sigma 28mm f1.8 Aspherical AF. This is the uncommon earlier version with the 58mm filter thread (same as the FA 31mm). Much smaller than the more recent EX model with the 77mm filter thread, yet the same max aperture of f1.8! One of the fastest 28mm lenses out there and one you don't see available for sale that often, especially in this condition. I'm including a center-pinch lens Sigma cap I bought for it, which is easy to take on and off while the hood is forward mounted.
Forum: Sold Items 08-20-2015, 02:42 AM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Sigma 24-135mm f2.8-4.5.
Forum: Sold Items 08-20-2015, 02:39 AM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Promaster Spectrum 7 100mm f3.5 AF Macro. This lens is by Cosina and you can also find it sold by Tokina and Pentax with their brands on it. While the build quality is nothing special (a lot of plastic), optical quality is well regarded, just check out the user reviews in this forum and elsewhere. This includes the matched diopter for 1:1 macro.
Forum: Sold Items 08-20-2015, 02:33 AM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
Pentax SMC DA 10-17mm ED IF f3.5-4.5 Fish-Eye
Forum: Sold Items 08-19-2015, 07:54 PM  
For Sale - Sold: Many lenses and accessories
Posted By nater
Replies: 47
Views: 9,403
More items added and I've made some price reductions. I'll post more pictures of the new items soon. What doesn't sell here will end up on ebay.
Forum: Pentax Camera and Field Accessories 06-09-2015, 08:53 AM  
It's Heie's fault if I got a Sirui T-025X! (personal short review inside)
Posted By nater
Replies: 35
Views: 6,564
It was not my intention to offend anyone, which it seems like I've done? Apologies if I have. I'll try to keep my thoughts and opinions more to myself if that's the case. I have high standards for everything including myself, and criticize myself every day in many ways, even when others say I'm doing terrific work. It's part of my personality, and I've been that way for decades. Best wishes to everyone.
Forum: Pentax Camera and Field Accessories 06-08-2015, 08:18 PM  
It's Heie's fault if I got a Sirui T-025X! (personal short review inside)
Posted By nater
Replies: 35
Views: 6,564
Hi Heie! Thanks for your review, it's definitely one of the better ones out there.



Those are manufacturer specs, and as I've mentioned they can't be trusted. I mean look at the games makers play, here's Cullman's Nanomax 200T CB 5.1 with it's 2kg weight rating:

https://www.cullmann.de/en/made-with-cu/made-with-cu/news/profi-fotograf-n-b...omax-200t.html

and then on that same page they link to a review from the famous photographer Nicolas Beaumont where he says:

"Even if the Nanomax 200T is not certified for more the 2kg I often worked with heavy gear on it, for exemple on the great wall near Beijing; it was loaded with the 1D Mk IV and 70-200 f/2,8 L; even like that it was stable !"

2.89kg clocks in at exceeding the "max" weight by almost 50%.

Some tripod makers are reasonably intelligent and actually list different weight ratings based on the angle, so for instance 3 Legged Thing has this in the specs of the EVO3 Punks Rick Carbon Fiber Tripod System:

23 - 20kg / 44lb
55 - 15kg / 33lb
80 - 10kg / 22lb



Not that I have the time or money right now, but to do it right I should probably launch a website and do a good series of comparative reviews. It's what I want to do.



The laser beam isn't a bad idea, but I prefer what Mark Banas does in his reviews: "With the legs fully extended and the center column lowered, our vibration analyzer (an iPad on a 3 lb (1.36kg) aluminum block) was mounted to the ball head with a long lens plate. A large solenoid valve with a plastic hammer was then used as a consistent source of vibration (a knock to the bottom of one leg). The resulting graph of all three accelerometers shows both the resistance of the tripod and head to the initial shock, as well as the rate of decay for residual vibration within the tripod."

The laser pointer test was from what I can tell a controlled setting with a single lens. While I like Mark Banas' test, it could be further improved upon. Ideally we'd have a picture of how a tripod does on a variety of surfaces in different leg length configurations at different temperatures with different lenses at different center of gravity orientations experiencing different vibrations (i.e. I might be out on an overpass with vehicle traffic causing vibrations in the road, how will the tripod cope? I might be near a large waterfall with the vibrations of falling water shaking the ground, how will those be absorbed? I might be on a windy hilltop, how much will the tripod flex, vibrate, and transmit that to the camera?) Obviously a review can't test every scenario, but some reasonable subset should be determined and tested.



The lack of failure cases actually made it harder for me to determine just how good the Sirui T-025X is.



"We"? I don't pretend to speak for anyone but myself. Are there other people out there like me? Sure. How many? I have no idea. But yeah I love long, detailed reviews with lots of data. Also ideally the comparison tables in a review would be dynamic and allow the reader to select multiple criteria, assign weights to them, and then generate unique and specific results for that reader. I think it's largely a mistake that so many sites task reviewers with creating static reviews that have a combination of implied and/or explicit criteria and then reaching a single conclusion (perhaps with a few variations).

Let me be clear - your review was good. Most reviews of photo equipment are terrible. But there is room and opportunity for reviews to be great.



Right, I haven't provided examples, so let me do that.

A great SD card market review:

On MicroSD Problems

A combination of using acid to dissolve the plastic casing, reveal the insides, and then use low level tools to reveal the card ID information, combined with good information about what companies actually make the flash and the controllers and how the market works, makes this great.

Pretty much any power supply review from jonnyGURU.com:

Andyson N700 700W Titanium Review

but also take note of the "Death of a Gutless Wonder" series:

Death of a Gutless Wonder V: Uncool to the Max Review

Why it's great is because it reviews the packaging, marketing, claims, aesthetics, physical design, fit and finish, extras, determines the true manufacturers of the parts and components, does cold bench tests and uses a $10,000 piece of testing equipment to hot box test and simulate a range of possible load scenarios, provide the collected data and oscilloscope graphs for the results, performs a teardown and analysis of the construction. Then the "Death of a Gutless Wonder" series provides that terrific counter-point to the excellent manufacturer-supplied power supplies by going out into the real world, buying something retail, cheap, off the shelf, testing it and seeing when it lets the magic smoke out.

The closest I've seen to this in the photo review world is S.C.V. Photography Ideas, with their reviews like this that have a tripod teardown in them:

S.C.V. Photography Ideas: Nest NT-6294CT Carbon Fiber Traveler Tripod Review

I think it's great, I'd love to see more of it in the photo world.

Any of John Siracusa's reviews over on Ars Technica, like his Yosemite review:

OS X 10.10 Yosemite: The Ars Technica Review | Ars Technica

25 pages that I really enjoy reading.

Hopefully this gives you some idea of where I'm coming from.
Forum: Pentax Camera and Field Accessories 06-08-2015, 11:47 AM  
It's Heie's fault if I got a Sirui T-025X! (personal short review inside)
Posted By nater
Replies: 35
Views: 6,564
I'd call it entry-level because from a construction standpoint because the metal parts are forged aluminum. Mid-range to high grade in my mind means magnesium alloys and/or CNC machining from solid metal blocks rather than forging.



Keeping an upper bound on the prices of tripods in a comparison makes sense, but keeping less expensive tripods out that otherwise are a close match in terms of size and design does not make sense to me. Regarding load capacity, there is no standard for rating a tripod or head, so I consider that value a manufacturer suggestion at best and not something I'd use to limit the range of tripods in a review.



I've noticed that Dolica has a lot of entry-level, very inexpensive tripods. I assume like many companies, they are re-branding tripods made by one of the big Chinese companies (probably Ningbo Weifeng Image Equipment Group Co., Ltd). Dolica's highest end product looks ok though from what I've gathered. Odd thing is, the higher end stuff seems harder to come by. There was also that brief period of time where Dolica acted as a reseller of Nest (the highest end product from Weifeng), and in fact is still selling a couple of alloy models at low prices (likely they moved all the carbon fiber Nest product already). The Nest product appeared to be higher end the top of the line Dolica. The Camera Cottage in Billings, Montana is the only place in the USA actively reselling Nest product right now, but it has good distribution in the UK and Australia as far as I know.



I think it's more complicated than "you get what you pay for". All indications are that the Field Optics Research Schonfeld KF6615T carbon fiber tripod, which sells for $199 from the Field Optics Research website or $149 from B&H, is the same tripod as the AmazonBasics 52-inch carbon fiber travel tripod, which sells for $79 with ball head. In some cases there isn't much correlation between price and value. That's why I read reviews and research things before I buy.

A more accurate statement could be, "Don't have high expectations for something you haven't paid much for relative to other products on the market unless you have research or data to back up those expectations."



My interest in this thread has to do with being able to extract good information to relay to people I know to help them make decisions, and additionally to help me make a purchase decision for a second tripod since my primary tripod, while terrific, is not very portable. I can see how portable might be nice, but I need to determine my thresholds for functional tradeoffs based on facts, not conjecture.



I'd agree based on Promaster's older tripods, but I'm not sure where they stand with these newer ones.



I don't doubt that your Sirui vibrates less than your Dolica if you say it does, but there are a lot of potential factors that go into vibration, such as the overall design and construction of a tripod, the diameters of the tubing, the type and design of the metal parts, etc. I have seen lots of speculation and contrary experiences based on materials. I've seen multiple people claim that a magnesium alloy tripod from a particular manufacturer is less vibration prone than a carbon fiber variant of the same model. Perhaps a well designed and well built metal alloy tripod could outperform an inferior designed and built carbon fiber tripod. Perhaps there are design features that work better in a tripod with carbon fiber vs. alloys and vice versa, so if a manufacturer simply swaps out one material for another without redesigning, they could be making an inferior product for the sake a bullet point feature on a box and a way to charge more. The best tripod review would in my opinion make mention of the materials used but then objectively test tripods to see how they actually perform and provide the data from those tests, rather than imply performance based on materials or construction, or just relay subjective impressions.
Forum: Pentax Camera and Field Accessories 06-05-2015, 09:23 PM  
It's Heie's fault if I got a Sirui T-025X! (personal short review inside)
Posted By nater
Replies: 35
Views: 6,564
So I've had some friends ask my advice on tripods recently. I came back to this thread, and the Sirui T-025x review on Pentaxforums (among other sources), and did my own tripod research as well. The T-025x does seem good overall, it's carved itself out a niche for itself above the questionable entry-level carbon fiber stuff, and below the bigger name brand carbon fiber things, putting some quality features into the very small travel tripod category. I was perplexed by a few things in the review however. I noticed the comparison table is chopped off on the right on page 10:

Sirui T-025x Travel Tripod Review - Value and Competition | PentaxForums.com Reviews

Also, I think the table is missing what would be some interesting competitors, and has at least one model which isn't really a competitor - the MeFoto RoadTrip is a bigger tripod that folds to 15.4", and the model listed is the aluminum RoadTrip, not even the carbon fiber model (which would be the one reason to include the MeFoto RoadTrip in the table IMO). The MeFoto Backpacker on the other hand folds down to the same 12.6" and is closer in weight to the Sirui. While the BackPacker is only available in aluminum, it is $150, which from all the reviews I've read indicate it's a quality tripod in it's class and a good value:

MeFOTO BackPacker Travel Tripod Kits - Choose Your Color!

Meanwhile, coming in at even less ($109) yet having similar specs is the Davis & Sanford TR553-P228 by Tiffen:

TRAVERSE TR-553-228 SUPER COMPACT TRIPOD WITH BALL HEAD

An then there's the $80 carbon fiber AmazonBasics 52-inch "Travel Tripod", which from what I've been able to gather doesn't have very good built quality (not surprising):

Amazon.com : AmazonBasics 52-Inch Carbon Fiber Travel Tripod : Camera Tripods : Camera & Photo

And there's the ($70 on Amazon at the time of this writing) Dolica TX570B150DS "Traveler 57" Tripod with Ball Head and Integrated Monopod" again in the same size and similar weight class, but again with (unsurprisingly) concerns about build quality:

TX570B150DS Reversible Traveler 57" Tripod with Ball Head and Integrated Monopod ? DOLICA

The consensus seems to be that while the Dolica has a quick release plate similar to Arca-Swiss, it's not quite compatible.

However the one that's really caught my eye is the Promaster XC522:

http://promaster.com/spec-sheet.html?catalog[name]=Promaster-XC522-Professio...ds][0]=1095138

It has good specs (though the only list the weight of the legs, not legs + head), good cost ($140), and the reports I've read from people who bought it are positive. It has an integrated monopod. I verified with Promaster today that the quick release plate is Arca-Swiss compatible.

By that same token, it's also worth looking at the Sirui T-005X, which is basically the $136 aluminum version of the T-025X from what I can tell, yet it has nearly the same weight as the carbon fiber version, which would be a good opportunity to test exactly what carbon fiber brings (i.e. how much more does carbon fiber actually dampen vibrations, allow tighter leg clamping and thus support more weight compared to aluminum, etc.)

There are also other things that I am curious about which weren't covered in the review, like the ease of access and quality of after-sale product support, which I think impacts value. It's nice that Sirui has a 6 year warranty, but if actually getting service and support turns out to be an ordeal or drawn out process, it's not worth much to me.
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