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09-27-2013, 05:54 PM   #271
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QuoteOriginally posted by redrockcoulee Quote
You will not get a chance to do this to any of my 120 negatives
(...)
.
now, this is really not a cooperative attitude, is it? surely there must be some you can spare? really nice clean cuts, i promise, nice sharp blades. be a team player and all that, for the greater good and pedagogical purposes :P

/me shudders at the thought of actually cutting where there's some data, and walks away "this joke has gone too far"

09-27-2013, 06:05 PM   #272
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QuoteOriginally posted by Wired Quote
I just left a deposit on one....
Must be nice to have a store nearby that carries Pentax.
09-27-2013, 06:12 PM   #273
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QuoteOriginally posted by Andi Lo Quote
Yes you're right, the perspective distortion is better controlled for wide angles with FF. Unfortunately contrary to my earlier argument about pedestrian lenses performing well, there is no Sigma 10-20 equivalent (value for performance wise) in FF if you need corner to corner sharpness, other than samyang 14mm, but it's MF. Even at f/8 most FF UWA doesnt' really deliver in the corners. The cheapest that have good corners is The Tokina 16-28mm at double the price of the sigma (followed by the Nikon UWA zooms and Canon's 17mmTS, all pricey). Other FF lenses even the 17-40L isn't as well designed at the sigma in the extreme corners.

This doesnt stop people from making great images with those lenses that are weak in the corners of course.... We also have the rather exotic Sigma 12-24 which at $300 used is cheaper than the Sigma 8-16mm. So you do get (way) more selection, just no cheap ticket for sharp corner-to-corner 10mm (APS) UWA in FF
The Sigma 10-20mm does sound pretty good resolution wise, but I heard the flare resistance is pretty bad on the lens and the rendering of the sun. The Tokina is probably the best choice for FF but no filter option kills it for me.

Also, I've been thinking about the real advantage of a FF sensor in terms of noise. FF sensor does have a 1-1.5 stops advantage over APS-C in terms of high ISO, but since the depth of field is lower, for night landscape/astrophotography where I don't want to compromise the depth of field, wouldn't the FF sensor need to bump up 1-1.5 f stops to achieve the same DOF as a APS-C sensor? If so, that actually eliminates any high ISO advantage of a FF sensor.
09-27-2013, 06:32 PM   #274
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QuoteOriginally posted by ofer4 Quote
Hi, gang -

Here's some info to fan the flames... I stopped in at my local camera shop today, which (as of about 1.5 years ago) did not carry Pentax. Two things:

1. They now carry Pentax! They had a full display case next to N&C, with K-5II, K-30, and one other that I can't remember...plus a full assortment of lenses and some P&S's.

2. The sales guy, who fashioned himself a Pentax aficionado, confirmed that an announcement is coming Oct 8 (without prompting). Interestingly, he said that the new body is designed to make the K-5II/K-5IIs the mid-level option. "Nearly everything" would be improved, relative to the K-5II. They'll have them in-stock around Nov 1.

I didn't have the guts to ask him about the future of FF.
Sounds close to what we know on the local forum too.
The local distro is showing Frank 'something' next week.

09-27-2013, 07:00 PM   #275
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QuoteOriginally posted by ElJamoquio Quote
Almost always, the corner sharpness in FF (lp/ph) exceeds that of APS-C.

It's the opposite in terms of lp/mm but I don't see why anyone should measure in lp/mm when considering resulting picture.
As you say this is only when "sharpness" is defined as line pairs per picture height and where the larger sensor is supplying more data to the same sized print for both formats (APS-C & FF).

If you measured resolution in absolute terms like LP/mm then I'm sure that a great lens on APS-C would have as good or higher corner resolution that the "equivalent" lens on FF where the pixel densities of the sensors were the same. This depends on the lenses selected of course - some APS-C lenses are capable of almost 60lp/mm whereas a FF may only do 30-40.

To be fair, all FF prints should be made 1.5x bigger than APS-C if you want to fairly judge actual resolution and not just accutance (sharpness). All things should be as equal as possible at that point.
09-27-2013, 07:09 PM   #276
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QuoteOriginally posted by catastrophe Quote
The Sigma 10-20mm does sound pretty good resolution wise, but I heard the flare resistance is pretty bad on the lens and the rendering of the sun. The Tokina is probably the best choice for FF but no filter option kills it for me.

Also, I've been thinking about the real advantage of a FF sensor in terms of noise. FF sensor does have a 1-1.5 stops advantage over APS-C in terms of high ISO, but since the depth of field is lower, for night landscape/astrophotography where I don't want to compromise the depth of field, wouldn't the FF sensor need to bump up 1-1.5 f stops to achieve the same DOF as a APS-C sensor? If so, that actually eliminates any high ISO advantage of a FF sensor.
For landscape if you shoot anything from 10-20mm at f4 and smaller, focused on anything over 3.5 meters from your sensor, everything is already hyperfocal. This is the same whether you use APS or FF, so DOF is moot for most landscapes.

Your logic is correct though, if you use moderate (not UWA) focal lenghts for your landscape and need to focus on objects that are 1 - 2meters to infinity, then you do eliminate the high ISO advantage as you need to stop down more. However, this doesn't mean that in this situation APS-C is better, just equal. Using FF I can always stop down and eliminate my high ISO advantage to get APS-C equivalent DOF, however I cannot reduce DOF to become FF-like when using APS-C.

Personally when using FF I do find it kind of annoying that I have to turn the wheel all the way to f 5.6 to get decent dof at 28mm

FF will always have more options for shooting compared to APS-C of the same gen except in weight and size (cost is debatable and depends on the FL / featureset, see my lens comparisons above). The weight and size argument imho only matters when lenses get as small as the DA limiteds, but that's for my use only. Pentax also has the advantage of small WR lenses. Canikon does not have any small WR lenses.

Pentax is possibly releasing their best body ever and I'm talking about FF in an internet forum.... I feel dirty now, so I think I'll stay away

Last edited by Andi Lo; 09-27-2013 at 07:23 PM.
09-27-2013, 07:11 PM   #277
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Very briefly on the topic "f/4 is f/4":

True in a sense just like "50mm is 50mm" is true in a sense.

But put two 50mm lenses on different format cameras and the images won't be the same (different FOV).

Use f/4 on two lenses with focal lengths chosen such they yield the same FOV on different format cameras and the images won't be the same (different DOF & different total amount of light gathered).

Exposure is not a good aspect for format comparisons because
  1. It was designed to be format agnostic (amount of light per unit area), and
  2. does not completely determine IQ (the total amount of light does).
It is an often neglected fact that an f/4 image on a large format collected a lot more light for the same scene than an f/4 image on a small format. Scaling both to the same output size hence results in noise advantages for the larger format. The different enlargement factors also influence sharpness (not relevant at f/8 but definitely when you reach lens performance limits wide open; small formats are stress testing lenses here) and how much (inevitable!) AF tolerances have an impact on critical sharpness.

But back on topic:
QuoteOriginally posted by ofer4 Quote
1. They now carry Pentax! They had a full display case next to N&C, with K-5II, K-30, and one other that I can't remember...plus a full assortment of lenses and some P&S's.
That's fantastic news.

I hope we'll hear a lot more stories of this kind in the future.

The K-3 sounds like a great package to me. I don't need more than 11 AF areas, but the 27 AF areas of the K-3 most likely imply that they will be smaller and thus better support target selection in terms of detail isolation.
09-27-2013, 07:13 PM   #278
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QuoteOriginally posted by Andi Lo Quote
I assume you mean:
DA 60-250 > Tamron 70-300 VC for a third of the price (slightly worse lens, but not a bad performer, one stop extra DOF at 70mm), or 70-200 /4 VR/IS for the same price (one stop extra DOF and shutter speed)
The point I was trying to make is that there's really not really a lot of "equivalent" FF glass to the outstanding slow glass. Also: even when there is an equivalency terms of DOF and FOV, there is no "equivalency" in terms of microcontrast, color rendition, rendering, or those other non-quantitative, non-measurable aspects. Remember that the Pentax limited lenses were not designed with numerical specs in mind; they were designed to create images that look beautiful to human perception. The DA 15 is not aesthetically equivalent to the Nikkon 20 f2.8. You can get more beautiful images out of that Pentax lens. That's why you'll find photographers claiming the DA 15 holds it's own with their Zeiss glass, or that it "controls their mind." Anyone ever said that about the Nikkon 20? I see images all the time from Nikon and Canon glass. I'm involved in bi-weekly critiques with other photographers who live in my area. Nikon and Canon have some wonderful FF glass. Great resolution, great clarity. But I don't see anyone getting the same richness and vividness of color out of their Canikon glass as I can out of my best Pentax glass.

09-27-2013, 07:28 PM   #279
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QuoteOriginally posted by northcoastgreg Quote
The point I was trying to make is that there's really not really a lot of "equivalent" FF glass to the outstanding slow glass. Also: even when there is an equivalency terms of DOF and FOV, there is no "equivalency" in terms of microcontrast, color rendition, rendering, or those other non-quantitative, non-measurable aspects. Remember that the Pentax limited lenses were not designed with numerical specs in mind; they were designed to create images that look beautiful to human perception. The DA 15 is not aesthetically equivalent to the Nikkon 20 f2.8. You can get more beautiful images out of that Pentax lens. That's why you'll find photographers claiming the DA 15 holds it's own with their Zeiss glass, or that it "controls their mind." Anyone ever said that about the Nikkon 20? I see images all the time from Nikon and Canon glass. I'm involved in bi-weekly critiques with other photographers who live in my area. Nikon and Canon have some wonderful FF glass. Great resolution, great clarity. But I don't see anyone getting the same richness and vividness of color out of their Canikon glass as I can out of my best Pentax glass.
I misunderstood, and 100% agree with you, I do find that Nikon 20 is nowhere near DA 15 when I compare the images Not necessarily slow glass too, DA 15, and FA 43, and FA 77 are imho very special and have no equal in Canon Nikon. It's indeed not all about specs. Canon Nikon have high performing lenses that do well in lab tests, but there's something special about pentax glass rendering (see the FA limiteds on 5D thread!). I still prefer my "slightly ghosty" FA 50 results to the Nikon 50/1.8, which technically is superior in every way and gets excellent lab results.

FA 50 combined with K100D / K20D with the right light can get a 3D effect that hits you like a brick wall!

Use the gear that will get you the shot, whatever "the shot" is to you

Last edited by Andi Lo; 09-27-2013 at 07:35 PM.
09-27-2013, 08:03 PM   #280
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QuoteOriginally posted by bossa Quote
As you say this is only when "sharpness" is defined as line pairs per picture height and where the larger sensor is supplying more data to the same sized print for both formats (APS-C & FF).

If you measured resolution in absolute terms like LP/mm then I'm sure that a great lens on APS-C would have as good or higher corner resolution that the "equivalent" lens on FF where the pixel densities of the sensors were the same. This depends on the lenses selected of course - some APS-C lenses are capable of almost 60lp/mm whereas a FF may only do 30-40.

To be fair, all FF prints should be made 1.5x bigger than APS-C if you want to fairly judge actual resolution and not just accutance (sharpness). All things should be as equal as possible at that point.
'To be fair'?

To be fair if I or someone else wants a 20x30" print I'll print it out in 20x30. No one is going to pay more for a pic just because I handicapped myself with APS-C.
09-27-2013, 08:22 PM   #281
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QuoteOriginally posted by Andi Lo Quote
This doesnt stop people from making great images with those lenses that are weak in the corners of course.... We also have the rather exotic Sigma 12-24 which at $300 used is cheaper than the Sigma 8-16mm. So you do get (way) more selection, just no cheap ticket for sharp corner-to-corner 10mm (APS) UWA in FF
No argument. With enormous skill and determination someone could get a great action shot with a medium format as well. I'm all for specialization in market offerings. A multipurpose anything is often a compromise, just as a zoom is a compromise for a worthy goal. Pentax probably needs a full frame body, and will release one at some time in the future because the demands of some shooters would be met by one. Working with a tool designed and optimized for a specific purpose is very satisfying. I can't see myself hauling a D800 and the large lenses for what I do, I would be using the crop mode anyways, so why bother with the extra weight and size. And aps-c works very well for what I shoot. But I understand the advantages of a larger format; less noise, better in many ways for some types of shooting.
09-27-2013, 08:30 PM   #282
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Just a thought regarding this FF vs Crop thing.. A larger sensor [full frame or otherwise] does not mean an image will be better. And noise is an issue that can be dealt with, particularly well with a Pentax light box.

Other than that, how exciting the K-3! I'm slowly building my arsenal [of glass] with a K-01, and had planned to get a K-30 [because I want weather-sealing] and then a K-5 IIs, but now I've decided I'd better get an MX-1 for street photography and be able to carry it anywhere everyday, and keep saving for a K-3. As excited as I am for the new Pentax flagship, I still know I won't buy it as soon as it comes out, but rather wait for a price-drop or simply until I finish saving up for it ^__^
09-27-2013, 08:39 PM   #283
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QuoteOriginally posted by konraDarnok Quote
Is it really?

"FF's advantage is shallower DOF at a given aperture."

"That's true, but APS-C's advantage is a greater DOF at a given aperture."



Worst part is it's all reactionary. If tomorrow Pentax brought out a 1500$ 645D that could achieve DOF equivalences at narrower apertures than FF, people would just bitch about the loss of absolute light gathering ability. These people want Pentax to be Nikon or Canon; I can't figure out why they just don't switch systems. Frankly wears me out.
You could have both though, surely, in the same camera.

Put a full frame lens on and have full frame. Put a crop frame lens on and select crop format.
09-27-2013, 08:59 PM   #284
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QuoteOriginally posted by jatrax Quote
I rarely go above ISO 400 on the k-5II, others say it is good higher than that but not for me, I struggle to keep 400 clean enough.
Seriously? Shooting RAW? On my previous original K-5 I routinely found no perceptible noise at 1600, and little enough at 3200 that LR's handy noise reduction slider would tame it lickety split.

A real-world example: My father-in-law passed away suddenly this summer and the funeral home asked for a portrait that they could display at the service. My mother-in-law chose a couples portrait that I had taken of them a few months earlier on their anniversary with my little $300 K-01 (same sensor, obviously). This was a full body portrait. I found out later that the funeral home cropped it to just a head-n-shoulders shot of just him. I had a little anxiety attack because I knew that it was ISO3200, and that they printed it at 16x20! I dreaded seeing it. I thought this would surely be asking too much of this admittedly great little sensor. But to my surprise, it looked fantastic! If not for the solemnity of the occasion, I would have been tempted to place a small original next to the portrait with a little placard saying, "Pentax did this!"

That portrait is hanging on my mother-in-law's wall today. She absolutely loves it and is eternally grateful to me for having taken it.
09-27-2013, 09:03 PM   #285
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QuoteOriginally posted by snake Quote
You mean an "I4". There are very, very, very few examples of non-inline 4 cylinders, outside of a flat configuration.
Lancia did it for a very long time, before they turned into Fiats in party frocks.
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