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11-27-2017, 06:08 AM   #31
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QuoteOriginally posted by BruceBanner Quote
Thanks for all the responses! I have to go to work now so shall take all this in better upon my return. I just wanted to point this out, that for the XS 40mm, there is no Field of View for Full-Frame listed. Is this because we're still in the infancy of testing ASP-C lenses that are compatible with the K-1, or perhaps the XS has been vetted already and the data not included here because it does actually indeed involve some minor vignetting and the purists (lol) don't want to add it here?

The FA 50mm for example I think lists Field of View for both FF and ASP-C?
Since the DA 40mm XC is designed for APS-C and not officially a full-frame lens we only show the FoV on APS-C.

If you'd like to know the FoV on your K-1 you can find it in the table for another forty mm lens, such as the smc Pentax-M 40mm.

We also have this handy table of FoV by focal length and sensor (film) size. Note that the table shows the horizontal Filed of View only.

11-27-2017, 10:56 AM   #32
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QuoteOriginally posted by Ole Quote
Since the DA 40mm XC is designed for APS-C and not officially a full-frame lens we only show the FoV on APS-C.

If you'd like to know the FoV on your K-1 you can find it in the table for another forty mm lens, such as the smc Pentax-M 40mm.

We also have this handy table of FoV by focal length and sensor (film) size. Note that the table shows the horizontal Filed of View only.
Not true I have noticed, some such as the HD DA 40mm Ltd. (which is also intended for APS-C) has the information for its lens for Full Frame FoV also, it just appears that we are slow to update all lenses that are compatible with FF FoV.

That is an excellent table, thank you for linking me that, I wish someone pointed this out a lot earlier as this is exactly what I was alluding to. As we can see a 40mm lens on ASP-C gives a FoV of 33.4, something between a 55mm and 75mm on a FF would be the equivalent FoV (hence my subject title guessing 60mm etc).

Cheers!

Bruce
11-27-2017, 12:49 PM   #33
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The HD DA 40mm Ltd. that you mention vignettes on full frame wide open but clears up nicely by f 5.6. Love it with the K-1! I assume it would be the same with the XS version.
11-27-2017, 01:02 PM   #34
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QuoteOriginally posted by sibyrnes Quote
The HD DA 40mm Ltd. that you mention vignettes on full frame wide open but clears up nicely by f 5.6. Love it with the K-1! I assume it would be the same with the XS version.
I haven't done a proper inspection yet with my XS, I only got it Friday and had a busy weekend. I shoot center weighted and often under expose my EV by -1 typically (as standard), so I get vignetting anyway. I noted that LR has the XS profile for Lens Correction and that seems to help with any vignetting etc. But I own a few APS-C lenses that do vignette badly (such as DA15mm), and so have a good idea of what to look out for, and first impressions was that whacking the XS on the K-1 and it appeared fine even at 2.8 (or certainly acceptable).

11-27-2017, 01:55 PM   #35
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QuoteOriginally posted by BruceBanner Quote
I shoot center weighted and often under expose my EV by -1 typically (as standard), so I get vignetting anyway.
How can metering mode or exposure compensation cause vignetting?
QuoteQuote:
First impressions was that whacking the XS on the K-1 and it appeared fine even at 2.8 (or certainly acceptable).
You'll need to check at minimum focal distance and infinity. Shoot a featureless, evenly lit subject - like a clear blue sky.
11-27-2017, 02:13 PM   #36
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QuoteOriginally posted by Sandy Hancock Quote
How can metering mode or exposure compensation cause vignetting?

You'll need to check at minimum focal distance and infinity. Shoot a featureless, evenly lit subject - like a clear blue sky.
Yes I reread that and realised it made no sense :S

Will do, hopefully we'll get a clear blue sky day later this week.
11-27-2017, 09:03 PM - 1 Like   #37
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One nice thing about the superb FA 77mm Limited is you can whack it on your K-1 as well with superb performance also. It is amazingly compact for its focal length, aperture speed, and imaging quality. It's bokeh (rendering of out-of-focus ares) is outstanding!

My comment regarding having to go to a lens of narrower FOV when wanting greater telephoto was meant to address how things work in the real world, which is what I think you are after.

Since you have both the KP and the K-1 (lucky you!) there is another word you have used interchangeably with FOV, which is perspective. They are two different things, but very much related. And this relationship is one reason why some people are inclined to acquire both cameras, as you have done. In the middle between a telephoto FOV and a wide-angle FOV is an area and related FL referred to as "Normal". But of course, a "normal" lens would have to be of different focal lengths when considering use with your FF K-1 or with your KP. The traditional "normal" lens from 35mm film use is the 50mm lens, although to be a stickler for accuracy, 50mm on a FF body is still slightly on the tele side in its FOV. As you've said, its equivalent FOV for your KP would be a 35mm lens. Now comes the relevancy of perspective. "Normal" also means using a lens where in the resulting image, things have a look in relation to each other that is very close to the same as would be seen being on location by the naked eye, when the image is taken at some distance, not a close distance.

This means objects in the background will appear to be of about the same size in relationship to the subject,, and therefore at the same distance behind the subject and foreground objects, as they appear when viewing the scene yourself while standing at the same spot.

With a lens going more into a wide angle FOV, objects in the background will appear smaller and farther behind the subject than in real life. Angled objects of some size- buildings, trucks, busses, etc. will appear elongated from front-to-back compared with real life. Vertical objets may appear to lean back or sideways unless one can manage to shoot from an absolute centered position. This is perspective distortion (not the usual linear distortion). But this is a price we must pay to get more into our frame. With a lens going into a more tele FOV, the opposite happens- the foreground and background are compressed, which is often used as an enhancement. Again, perspective distortion.

Now back to your two camera bodies. True "Normal" for a FF body is actually considered to be 43mm. Probably the reason for the FA 43mm Limited design. I have enjoyed this lens even more for 35mm film use (FF) than for APS-C, as I have found its FL and wider FOV more versatile, that is usable for a greater variety of scenarios. But the other thing is its ideal "normal" perspective. It renders say, a street scene in a way that has a very natural look, more so than any other lens, as well as being really fine in the usual sense of "rendering". So for FF use, this is a very special lens. That said, the FA 50mm f/1.4 s a fine lens and is close enough to "normal"perspective to be considered as a "normal" lens, though it does not get quite as much into the frame.

Although for APS-C one could effectively get a similar natural perspective by using a 28mm lens, there is no such animal as a 28mm f/2 that small, and that well-made, which has comparable "rendering" qualities. There are, however, very good alternatives for getting very close to ideal "normal"perspective with your KP. The top pick would be the FA 31mm f/1.8 Limited. This lens will have all the other "rendering" qualities of the FA 43mm LTD on the K-1 and then some- its bokeh is top-notch. even better than the 43mm. Its wide-open aperture performance is also better. Like the FA 43mm "normal" on your K-1 compared to a 50mm "normal" lens, it lets more into the frame with your KP than would a 35mm "normal" lens. However, it is quite expensive, with its ultra-fine Limited build quality. But it is also of course, fully compatible with your K-1 as a wide-angle fast lens.

As an alternative, there is my 2nd top pic, the FA 35mm f/2, which is of the same caliber of build as your FA 50mm lens, but somewhat better by having a good dedicated lens hood. Its performance is excellent, including very good booked. Very good, even at wide open aperture. It's price is reasonable, and it provides the FOV and perspective your 50mm lens provides on your K-1. A very good "normal" lens for your KP. Having been designed for film (FF) use, it can also serve as a very versatile moderate wide angle lens on your K-1. This means you get more into the frame than you would with your 50mm or 43mm "normal" lens, and since the wide angle is moderate, there is not a lot of perspective distortion.

Last edited by mikesbike; 11-27-2017 at 09:14 PM.
11-27-2017, 11:11 PM   #38
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Hi Bruce
You will now have to take both camera's and all your lenses when you go out now .
See how the mind messes with you !!!
Stop worrying and take more pictures you can crop when you get home.
How many photo's don't you crop anyway? ( straightening horizons etc )

Dave

11-27-2017, 11:50 PM   #39
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QuoteOriginally posted by dbs Quote
Hi Bruce
You will now have to take both camera's and all your lenses when you go out now .
See how the mind messes with you !!!
Stop worrying and take more pictures you can crop when you get home.
How many photo's don't you crop anyway? ( straightening horizons etc )

Dave
I do. This thread was about wrapping my head around lenses FL and how it appears (perspective wise) on different formats. With a greater understanding of this I can better shop for lenses that 'fill the gap' so to speak.
11-28-2017, 02:11 AM   #40
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Hi Bruce

Yes I was a bit flippant with my answer.
I've only got a K 5 11 so what I see is what I see no extra thinking whith the lenses I own.
Filling gaps mmm how many lenses do you want or need?
See 2 formats so many choices
Enjoy your photography,
with time which lens on which camera will become second nature
Dave
11-28-2017, 02:46 AM   #41
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Hi Bruce, this article from the PF staff has a great graph for comparising all focal lenghts on all sensor/film formats to the FoV:
The Crop Factor Unmasked - Articles and Tips | PentaxForums.com

And here's a list of DA lenses usable on the K-1 without or low vignetting (slightly outdated, but still good in addition to the Ricoh FF roadmap):
RiceHigh's Pentax Blog: Compatibility of DA Lenses on Full Frame
11-28-2017, 03:42 AM   #42
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QuoteOriginally posted by dbs Quote
Hi Bruce

Yes I was a bit flippant with my answer.
I've only got a K 5 11 so what I see is what I see no extra thinking whith the lenses I own.
Filling gaps mmm how many lenses do you want or need?
See 2 formats so many choices
Enjoy your photography,
with time which lens on which camera will become second nature
Dave
I have a FA 50mm, which on the KP gives a FoV similar to what owning a FA77mm on the K-1 would look like, then I have a DFA 100mm, which if I stuck on the KP gives a FoV similar to what a 150mm lens would look like on the K-1. The DA 40mm XS gives an equivalent FoV as to what a 60mm would look like on the K-1 (when placed on the KP). So I'm starting to see where I should head with things. The DA 200mm on the KP looks like what a 300mm on the K-1 would look like, perhaps that would be my next lens, one lens gives me two new reaches I don't yet have...
I think I must stick a sticker or note on the lens and what the FoV equivalent is when placing these lenses onto the KP. Perhaps a silver sticker note because the KP is silver

QuoteOriginally posted by angerdan Quote
Hi Bruce, this article from the PF staff has a great graph for comparising all focal lenghts on all sensor/film formats to the FoV:
The Crop Factor Unmasked - Articles and Tips | PentaxForums.com

And here's a list of DA lenses usable on the K-1 without or low vignetting (slightly outdated, but still good in addition to the Ricoh FF roadmap):
RiceHigh's Pentax Blog: Compatibility of DA Lenses on Full Frame
Cheers for that, the first one I knew of, still couldn't get my head around, the second link I have not seen, helpful and handy, ta!
11-28-2017, 04:14 AM   #43
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You can very easy calculate the equivalent focal length with the crop-factor of 1.5x. Simple math, don't need a calculator for it
DA* 200 is good, but i recommend to go directly to 300mm (depending on your budget and use).
Also the screwdriven F* and FA* telephoto primes are faster and less expensive than the DA* SDM telephoto primes, but you don't have the weather sealing of the DA*.
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