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03-25-2018, 07:44 AM   #376
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QuoteOriginally posted by Doundounba Quote
even Olympus doesn't claim their 60mm macro as a "2:1" lens - so the precision of the definition gives me something solid to beat them over the head with rely on.
they say 2.5x magnification for their 30mm
Olympus M.Zuiko ED 30mm f3.5 Macro lens | Olympus


Last edited by BigMackCam; 03-25-2018 at 07:49 AM.
03-25-2018, 07:51 AM - 1 Like   #377
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QuoteOriginally posted by Pål Jensen Quote
No it isn't as they will give different exposure. The numerical aperture do not refer to DOF.

Sorry for bringing up "equivalence". Equivalence doesn't exist.
Of course they will give a different exposure - until you adjust the ISO to compensate. Once you do that, you'll find that not only are the angle of view and DOF the same but the noise level is too. Equivalence DOES exist, but it's hard to achieve - did you miss the second part of my statement?
03-25-2018, 07:59 AM - 4 Likes   #378
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QuoteOriginally posted by Rondec Quote
The K-1 is not that much bigger than a K3 and the K-1 shoots 6.5 fps in crop mode versus the K3's 8 fps. Obviously it would be foolish to buy a full frame camera only to shoot in crop mode, but if you know that you are not going to be using the borders of your image anyway, then it works.

I'm sorry, but I still don't buy the lens longer argument and in particular, as pixels get more dense, it becomes harder and harder to get pixel sharp images.

But I apologize as well for this rabbit trail. This has nothing to do with the K3 III which hopefully will be announced by the end of the year and feature some higher level features than we have seen here to fore in a Pentax camera.
There's no need to apologize because this so-called rabbit trail is crucial to thinking about the design of the future K-3. There's at least three major differences between the K-3 and K-1 lines that affect how Pentax should design the K-3:

1. smaller physical size and weight of the K-3iii (and DA lenses) versus the K-1ii (and DFA lenses)
2. the potential for higher fps at reasonable cost in an APS-C sensor (versus full-frame sensor)
3. the higher "reach" or end-to-end magnification of APS-C images with a given optical focal length or macro magnification setting.
4. price point (is the K-3iii the less expensive "pro" body or is it much the same price as the K-1 but with higher performance in other areas)

Ideally, the K-3 should fill a distinct niche that does not replace or cannibalize the K-1 so much as extend the Pentax product line in a distinct direction (e.g., skittish wildlife photography).
03-25-2018, 10:36 AM   #379
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QuoteOriginally posted by Mark Ransom Quote
Of course they will give a different exposure - until you adjust the ISO to compensate. Once you do that, you'll find that not only are the angle of view and DOF the same but the noise level is too. Equivalence DOES exist, but it's hard to achieve - did you miss the second part of my statement?
QuoteQuote:
Having a 400mm F/5.6 lens on m43 is EXACTLY the same as having 800mm F/11.2 on FF
Well. For equivalence you'd need same working distance, same pixel pitch, same DoF and same exposure I guess? Note the working distance, otherwise you are changing the perspective as well.

03-25-2018, 11:23 AM - 1 Like   #380
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QuoteOriginally posted by Mark Ransom Quote
Of course they will give a different exposure - until you adjust the ISO to compensate. Once you do that, you'll find that not only are the angle of view and DOF the same but the noise level is too. Equivalence DOES exist, but it's hard to achieve - did you miss the second part of my statement?
Are you telling us that the point of various format is to have the same noise level?

---------- Post added 03-25-18 at 08:26 PM ----------

QuoteOriginally posted by fromunderthebridge Quote
Well. For equivalence you'd need same working distance, same pixel pitch, same DoF and same exposure I guess? Note the working distance, otherwise you are changing the perspective as well.
You also need the same DOF range and maxumum DOF in order for lenses to be equivalent. Also the same maximum magnification. It is impossible.

Let me add that shooting at F:11.2 will never be equivalent to shooting at F:5.6. Not only by definition, but also due to the fact that you can AF at F:5.6 and hardly focus at all at F.11.2.

Last edited by Pål Jensen; 03-26-2018 at 03:25 AM.
03-25-2018, 01:02 PM - 1 Like   #381
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QuoteOriginally posted by Doundounba Quote
Heheh - funny! "Except for these two HUGE differences, there wouldn't be any difference!"

Which is to say that even if there existed a 52MP, 8fps shooting, $5k+, K-WOW camera, I'd still be hoping for a K-3III in 2018!

Yes, I do agree with that, and I've had that very "conversation" with macro shooters claiming to be shooting "2:1 magnification" when they're actually using a (standard, Olympus) 1:1 macro lens on their m4/3 bodies. Sometimes people will do anything to make themselves or their photos (or their lenses, if they are lens manufacturers) seem more impressive. At least in macro photography, the definition of magnification is pretty clear - even Olympus doesn't claim their 60mm macro as a "2:1" lens - so the precision of the definition gives me something solid to beat them over the head with rely on.
I guess I am more asking the question "Why would someone who owns a K-1 be interested in a K3 III?" The K1 was being offered for 1700 dollars with grip included, recently, so I suppose that means that the K3 III has to be somewhere in the 1100 to 1400 dollar range. It isn't as though there is a huge difference in price between top end APS-C and low end full frame, at this point, and while the K-1 is a top end camera for Pentax, it is still priced like an entry level full frame camera.

For serious macro and even wildlife, crop cameras offer a significant discount over full frame cameras with minimal downside, but if someone shoots a lot of different things -- portraits, landscapes and occasionally macro -- then they might still end up with a full frame camera and figure out how to make it work.
03-25-2018, 01:32 PM   #382
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QuoteOriginally posted by Rondec Quote
I guess I am more asking the question "Why would someone who owns a K-1 be interested in a K3 III?" The K1 was being offered for 1700 dollars with grip included, recently, so I suppose that means that the K3 III has to be somewhere in the 1100 to 1400 dollar range. It isn't as though there is a huge difference in price between top end APS-C and low end full frame, at this point, and while the K-1 is a top end camera for Pentax, it is still priced like an entry level full frame camera.

For serious macro and even wildlife, crop cameras offer a significant discount over full frame cameras with minimal downside, but if someone shoots a lot of different things -- portraits, landscapes and occasionally macro -- then they might still end up with a full frame camera and figure out how to make it work.
For the same field of view, using lenses specific to the format, an APS-C camera and lens is going to be smaller and lighter. And anywhere from a lot, to just a little bit, cheaper. But it still makes a difference.

I have full frame and APS-C cameras. Admittedly, different brands, but still... If I put aside my A7 MkII, as it's not a realistic comparison, my other full-frame camera is a Hasselblad HV (i.e. Sony A99 in a sharper, tougher suit). It's a little wider than the K-1, but otherwise very similar in size and weight. Add on a decent 24-70 f/2.8 lens and it's a chunky, reasonably heavy package. Perfectly usable, of course, and use it I do... but my K-3 (or K-3II) plus 17-50 f/2.8 makes for a smaller and lighter package that's much nicer to carry around for an afternoon, and certainly for a whole day - even more so if I'm carrying other APS-C format lenses with me. Of course, I don't get the same shallow depth of field and subject separation with the APS-C setup, but often that's a compromise I'm willing to accept. I say "often"... I mean "usually", as however much I love my HV and Sony Zeiss 24-70 f/2.8, I choose my K-3 far more frequently, and have taken a far greater number of photographs with it as a result. It's just less tiring and tiresome to carry for longer periods. None of this takes away from my HV... it just means that I'm more likely to take the K-3 because the format and size combination (and compromise) happens to work very well - for me

For the same reason as above, I can totally understand why some people choose micro 4/3rds. It's not for me, but I completely get the desire for smaller, lighter kit. It's just that my needs are satisfied by Pentax APS-C gear, so I have no personal need to go to a smaller format

Last edited by BigMackCam; 03-25-2018 at 01:39 PM.
03-25-2018, 03:59 PM   #383
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QuoteOriginally posted by photoptimist Quote
There's no need to apologize because this so-called rabbit trail is crucial to thinking about the design of the future K-3. There's at least three major differences between the K-3 and K-1 lines that affect how Pentax should design the K-3:

1. smaller physical size and weight of the K-3iii (and DA lenses) versus the K-1ii (and DFA lenses)
2. the potential for higher fps at reasonable cost in an APS-C sensor (versus full-frame sensor)
3. the higher "reach" or end-to-end magnification of APS-C images with a given optical focal length or macro magnification setting.
4. price point (is the K-3iii the less expensive "pro" body or is it much the same price as the K-1 but with higher performance in other areas)

Ideally, the K-3 should fill a distinct niche that does not replace or cannibalize the K-1 so much as extend the Pentax product line in a distinct direction (e.g., skittish wildlife photography).


Nice tie in to the topic.




03-26-2018, 01:59 AM   #384
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QuoteOriginally posted by Mike.P® Quote
You have echoed my post on another forum almost word for word although I will keep my K-1 and selection of lenses for full frame shooting.
Am also waiting for the 7DIII (currently use the MKI) and am looking for a mint 400mm f4 DO II
Honestly, the fact that the new K3 mkIII with 50 point SAFOX 13 and the KP sensor/accelerator unit, that everyone more or less expected, is now only starting to be developed, and the AF upgrade is not at all a given, has been the last push.
The Canon 7DIII will almost certainly have significantly improved sensor performance, and one can only speculate on the AF performance.
The KP is a very fine camera, and will be perfectly ok. until the 7DIII arrives. I will be buying the 400mm f4DOII lens new myself, because I can then trade in the DA560 + DA1.4TC. I don't see much perspective in trying to sell the lens privately.
Perhaps more will do what you are about to do: use Pentax for its forte, and carry another system next to it.
03-26-2018, 02:38 AM   #385
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QuoteOriginally posted by Chris Mak Quote
The Canon 7DIII will almost certainly have significantly improved sensor performance, and one can only speculate on the AF performance.
Canon 80D has already a sensor as good as the one from K-3 II. K-3 II has an edge when comes to fine details on files at low ISO due to the fact that it can shoot without AA filter. Canon will not put a less good sensor in the next APS-C flagship than the one existing in the 80D. That's for sure. But, be prepared because it will be an expensive camera. If wildlife is going to be your main activity, with all respects to all Pentaxians but Pentax will never going to get close to Canon and Nikon in this area as long as they are not going to invest big money. And as I said, to me Pentax cameras looks more and more dedicated on professional landscape photographers (GPS, atrotracer, intervalometer, WR bodies, pixel shift, etc.).
03-26-2018, 02:42 AM   #386
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QuoteOriginally posted by biz-engineer Quote
I've seem some people even shoot wildlife with a wide angle lens using RF triggers to take the shots.
It's a 28mm lens wide enough for wildlife? We use rotating heads that move vertically or horizontally our cameras because once we put a cameras on a stand, it stays there and we control the angle of our cameras from a remote and we also have remotes for triggering cameras. Here we used a Nikon D800 of a very good friend of mine.
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03-26-2018, 02:55 AM   #387
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QuoteOriginally posted by Chris Mak Quote
Honestly, the fact that the new K3 mkIII with 50 point SAFOX 13 and the KP sensor/accelerator unit, that everyone more or less expected, is now only starting to be developed, and the AF upgrade is not at all a given, has been the last push.
I think you're doing the right thing, Chris. It's been clear for a while that Pentax doesn't offer what you want, so you should absolutely switch to a brand that does. I really like my Pentax gear and it does pretty much all that I need, but if I found it seriously lacking and felt it was negatively impacting my enjoyment of the hobby, I'd switch in a heartbeat. It's not like breaking up with a spouse or girlfriend - this is just equipment
03-26-2018, 03:04 AM - 5 Likes   #388
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QuoteOriginally posted by BigMackCam Quote
I'd switch in a heartbeat. It's not like breaking up with a spouse or girlfriend - this is just equipment
Thin ice Mike.
03-26-2018, 03:15 AM - 1 Like   #389
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QuoteOriginally posted by BigMackCam Quote
I think you're doing the right thing, Chris. It's been clear for a while that Pentax doesn't offer what you want, so you should absolutely switch to a brand that does. I really like my Pentax gear and it does pretty much all that I need, but if I found it seriously lacking and felt it was negatively impacting my enjoyment of the hobby, I'd switch in a heartbeat. It's not like breaking up with a spouse or girlfriend - this is just equipment
I think the big thing for Chris is to follow the lenses he wants. I know he has gotten by with the DA 560 for awhile, but if there are other long lenses he wants to try that aren't available in the K mount, that certainly is plenty of reason to move to a different camera body. Pentax certainly has most of the bread and butter lenses covered, but other than the Bigma, DFA 150-450, DA 300 (with TC) and DA 560, they are pretty lacking on the long end of things.
03-26-2018, 06:25 AM - 2 Likes   #390
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QuoteOriginally posted by Pål Jensen Quote
But again photographers are not interested in exact subject magnification, but how much the subject fill the frame. To get an image like 1:1 maginification on 4/3, you'll need a 2:1 lens on FF. Or for the same frame filling properties you can use longer working distance on the smaller format; very useful for macro.
Alright, I will answer to this exactly once.

1) "photographers are not interested in exact subject magnification"
  • Many macro photographers, entomologists and nature lovers are interested in exact subject magnification, since that is what allows one to determine subject size.
  • The point is that some people (and sometimes lens manufacturers) are being dishonest about their figures. There are not five definitions of magnification in macro photography. There is one: the ratio of the size of the image produced on the sensor relative to the size of the subject. 17.5mm long subject fills your 17.5mm wide m4/3 sensor is 1:1. If you are stating another number, you are at best mistaken, at worst dishonest.
2) "To get an image like 1:1 maginification [sic] on 4/3, you'll need a 2:1 lens on FF"
  • Hey, you actually used magnification in this sentence! I thought you weren't interested in magnification or its exact definition?
  • This is the equivalence issue. If you're shooting 1:1 on a 16MP m4/3 camera, you're getting 16MP on a 17.5mm subject. Shooting 2:1 on a 36MP full frame, you're getting 36MP on the same subject! That's not the same result at all! A more meaningful comparison is to ask how much magnification you need to get the same number of pixels on the same size of subject. (This assumes pixel-sharp images and discounts things like noise and DR, and so is not without issues either, but I contend it is at least more meaningful than your own fairly ludicrous statement.) My math is a little rusty, but I believe the answer to that is 1.33:1. Shooting 1.33:1 on a 36mp full frame camera will give you a 16MP cropped image that is 17.5mm wide. So, to get back to your statement, to obtain an image roughly like 1:1 magnification on a 16MP m4/3 camera, you'll need a 1.33:1 lens on a 36MP FF camera. Comparing other pixel count cameras, or other formats entirely, is left as an exercise to the reader.
3) And as to working distance, now you need to take focal length into consideration as well, in order to make a meaningful comparison.


This doesn't mean you can't shoot fantastic macros on m4/3 - because you definitely can. It doesn't even mean that there is no advantage to shooting high magnification, low-iso, flash macro on a more pixel-dense sensor. It just means that definitions matter, and people (or lens manufacturers) claiming inflated magnification figures based on the crop factor of their camera are mistaken at best, and dishonest at worse.

Last edited by Doundounba; 03-26-2018 at 12:25 PM.
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