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10-02-2014, 10:33 PM   #121
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QuoteOriginally posted by Rondec Quote
Obviously there are differences at high isos.
By about 1.25-1.5 stops (~1200 ISo vs ~2900 ISO) according to the DxOMark gods.

But the DxOMark numbers can be deceiving. I've looked very closely for example at the 6D vs the D610 results and even though 6D scores lower than the D610 at high ISO (~2200 vs ~2900), the 6D results consistently look better - cleaner blacks, less chroma noise etc. What DxOMark measures is not always clear to see in the output.

It's pretty easy to see in comparing K-3 to D610 at ISO 6400 though. No argument there.

10-02-2014, 11:14 PM   #122
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Hmm, the OP has not been getting in a word the last few pages...
For astro images I suggest getting fishy with the Sigma 15: really wide, f/2.8, close focus, full frame friendly. For me the smc17 is sufficient, all the above except f/4. Pentax has stated video is not a priotity, if it is for you then your answer is 'go'.
10-03-2014, 02:35 AM   #123
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QuoteOriginally posted by ElJamoquio Quote
Uh... yes? 20% is hard to see. Keep in mind that in most of this thread people were conflating no-AA with APS-C.

I wasn't accusing you of bashing the D600, FWIW.

Out of curiousity, what cameras are you comparing? Maybe I'm overlooking it but I don't see a Pentax K-3 as a comparison in the dpreview studio shot.
I see it here: Image comparison: Digital Photography Review
10-03-2014, 08:18 AM - 1 Like   #124
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I was about to leave, but now, im staying, just because of one lens.

Sigma 18-35mm F1.8

This make the K3 so good as a Nikon D4s.

It would be great if the new Pentax lenses were:

18-45mm f/1.8
50-140mm f/1.8


Then you wouldnt need full frame, or any other camera, and I will be very very happy doing weddings with my apsc Pentax, and the low noise/high iso capabilities, and the stupid amount of fps, and the ergonomics, and the WR, ande PRICE, so I could have 2 bodies. And in the K3 II maybe they realize that video in 4k is important too, and then I could do some movies with the amazing vintage SMC pentax lenses, since I dont need autofocus anymore for video.

Sorry, I went crazy. Go #$%@$ yourself Nikon. Im staying Pentax, with FF or not FF.

10-03-2014, 08:46 AM   #125
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Sigma has said they're working on a 'unique' prime and a 'unique' zoom. The interview made it seem like the lenses would be along the same lines as the 18-35 F/1.8. We'll see though.

A 50-140 F/1.8 is possible of course... seems unlikely to me.
10-03-2014, 08:54 AM   #126
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QuoteOriginally posted by Enrique S Toso Quote

It would be great if the new Pentax lenses were:

18-45mm f/1.8
50-140mm f/1.8


Then you wouldnt need full frame, or any other camera,
The first might be possible, but would probably be larger, more expensive (or just worse) than the Sigma 18-35 1.8. I don't think the second is really possible to do in an affordable or non-enourmous way, or it would have been done by now.

But you're right, if you were a zoom-centric shooter, those two lenses if possible and affordable would make FF almost unnecessary to you.
10-03-2014, 09:02 AM - 1 Like   #127
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QuoteOriginally posted by Enrique S Toso Quote
I was about to leave, but now, im staying, just because of one lens.

Sigma 18-35mm F1.8

This make the K3 so good as a Nikon D4s.

It would be great if the new Pentax lenses were:

18-45mm f/1.8
50-140mm f/1.8


Then you wouldnt need full frame, or any other camera, and I will be very very happy doing weddings with my apsc Pentax, and the low noise/high iso capabilities, and the stupid amount of fps, and the ergonomics, and the WR, ande PRICE, so I could have 2 bodies. And in the K3 II maybe they realize that video in 4k is important too, and then I could do some movies with the amazing vintage SMC pentax lenses, since I dont need autofocus anymore for video.

Sorry, I went crazy. Go #$%@$ yourself Nikon. Im staying Pentax, with FF or not FF.
When I shot with the E-3 the only two lenses I had were the 14-35mm F/2 and the 35-100 F/2. Both of those lenses gave me excellent IQ and provided the "equivalent" 28-70mm and 70-200mm, but...... They both cost over $2,000 at the time and were bigger and heavier than their Canon/Nikon FF versions. For all practical purposes the 35-100mm F/2 give you a 70-200mm F/4 equivalent lens that is bigger and more expensive than a 70-200mm F/4 lens. This was back before Nikon/Canon updated their 70-200mm lenses with OIS, so I don't know how they would compare today.

Sure. Sigma or Pentax "could" build a 50-140mm F/1.8. Realize that it will be bigger and probably more expensive than a 70-200mm F/4 of the same quality and provide the same performance. Smaller sensors have to be enlarged more, so the lenses have to sharper to get the same results. Yes, there is a point of diminishing returns and if all you do is display images on the web, then it really doesn't matter. But if all you are doing is displaying images on the web you wouldn't need a 50-140mm F/1.8 anyway. For large prints F/1.8 is a real challenge as we get into how magnification effect DoF.
10-05-2014, 10:52 PM   #128
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QuoteOriginally posted by Winder Quote
When I shot with the E-3 the only two lenses I had were the 14-35mm F/2 and the 35-100 F/2. Both of those lenses gave me excellent IQ and provided the "equivalent" 28-70mm and 70-200mm, but...... They both cost over $2,000 at the time and were bigger and heavier than their Canon/Nikon FF versions. For all practical purposes the 35-100mm F/2 give you a 70-200mm F/4 equivalent lens that is bigger and more expensive than a 70-200mm F/4 lens. This was back before Nikon/Canon updated their 70-200mm lenses with OIS, so I don't know how they would compare today.


If you only care about DoF then you will feel that way. A f/2 is a f/2 in terms of light and to real photographers that's what matters the most. I don't think you can buy a 70-200 f/2 full frame at all.

10-05-2014, 11:09 PM   #129
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I'm a 'real photographer' and I care about SNR, DOF, FOV, and TLA.
10-05-2014, 11:23 PM   #130
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Should I stay? Or, should I go?

QuoteOriginally posted by ElJamoquio Quote
I'm a 'real photographer' and I care about SNR, DOF, FOV, and TLA.

So why compare f/2 and f/4? That's two stops of difference.
And be more specific and say you care only about shallow DoF
10-06-2014, 07:53 AM   #131
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I said I care about dof. I didn't say I care about the ratio between aperture diameter and focal length.... because I don't.

I did not say I care about shallow dof. I said I care about dof.
10-06-2014, 10:33 AM   #132
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QuoteOriginally posted by dtmateojr Quote
So why compare f/2 and f/4? That's two stops of difference.
Your aperture is literally a function of focal length. If you change the focal length of the lens, you are changing the diameter and area of the aperture. I you decrease the focal length of a lens then you are decreasing the size of the aperture and obviously decreasing the quantity of light it projects onto the sensor.

My 35-100mm F/2 - at 100mm F/2 had an aperture area of 1,963.5 mm^2

A 200mm F/2.8 lens = aperture area of 4,006 mm^2 wide open.
A 200mm F/4 lens = aperture area of 1,963.5 mm^2 wide open.

A 100mm F/2 lens provides the FoV of a 200mm lens, but it allows the same amount of light in as a 200mm F/4 lens.

The camera is calculating exposure off of tables just like we did in the early days and then camera is going to apply digital gain to reach the traditional 18% reflectance or a brightness of 46.6% sRGB. So if I have the 4/3 and a FF cameras both set to the same setting (100 ISO, F/4, 1/250) everything will meter the same, but the 4/3 camera is going to have to apply more digital gain (more noise) in order to achieve the same level of brightness.
10-06-2014, 10:54 AM   #133
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This probably has already been said, but if pentax made a budget mirrorless retro slr full frame id buy it in a heart beat -- however, i sold my K01 and K5 and jumped to a Nikon D600. Im not impressed with the output (its great, but so is the pentax). My friend was over with my old pentax K01 and 35mm F2.4 DA lens. we took sample portrait photos with his setup versus my Nikon D600 with 85mm F1.8G at the same fstops (2.4 and then 5.6). We both slightly perfered the output of the pentax -- but i was quite shocked to see at F5.6 when ISO was pushed up over 5,000 that noise looked about the same on both.

i use to do a lot of indoor non flash photography so i lusted for the full frame, but by the time i got the D600 i really dislike indoor photography all together so its a moot point now. for the deals ive been seeing a K3 with grip, flash, etc for $996 you wouldn't regret the purchase.
10-06-2014, 01:37 PM   #134
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QuoteOriginally posted by Winder Quote
Your aperture is literally a function of focal length. If you change the focal length of the lens, you are changing the diameter and area of the aperture. I you decrease the focal length of a lens then you are decreasing the size of the aperture and obviously decreasing the quantity of light it projects onto the sensor.

My 35-100mm F/2 - at 100mm F/2 had an aperture area of 1,963.5 mm^2

A 200mm F/2.8 lens = aperture area of 4,006 mm^2 wide open.
A 200mm F/4 lens = aperture area of 1,963.5 mm^2 wide open.

A 100mm F/2 lens provides the FoV of a 200mm lens, but it allows the same amount of light in as a 200mm F/4 lens.

The camera is calculating exposure off of tables just like we did in the early days and then camera is going to apply digital gain to reach the traditional 18% reflectance or a brightness of 46.6% sRGB. So if I have the 4/3 and a FF cameras both set to the same setting (100 ISO, F/4, 1/250) everything will meter the same, but the 4/3 camera is going to have to apply more digital gain (more noise) in order to achieve the same level of brightness.

I don't want to go down that rabbit hole but that is BS. But in case you are interested:

http://dtmateojr.wordpress.com/2014/09/28/debunking-equivalence/
10-06-2014, 01:54 PM   #135
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QuoteOriginally posted by buttons Quote
a Nikon D600 ... i use to do a lot of indoor non flash photography so i lusted for the full frame
I was disappointed a while ago to see that the D600/D610's autofocus was only rated to work down to -1 EV - just like the K-x and K-5. So the D600/610 were probably never the best choice for indoor low-light.

D750 and the 6D, on the other hand, do -3 EV autofocus, just like the K-3 and K-5II, so probably fit the bill better for indoor low-light.
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