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07-06-2012, 09:19 AM   #481
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QuoteOriginally posted by cfraz Quote
True. I have to admit the 2 times factor in amount of light for FF /APSC dominates any effect of the B/A ratio. Nevetheless, the best manual focus SLRs had bigger, brighter viewfinders than the best FF DSLRs now have, if recent posts are correct.
Which is a gap Pentax could exploit in FF. most are 100% FF but they have low magnification ratios - some recent models from the 3 FF guys which shows there is still room to improve the experience pretty dramatically on the magnification end
Nikon
D700 - 95% .72x
D800 - 100% .7x
D4 - 100% .7x
Canon
1DC - 100% .74x
5DIII - 100% .71x
1DX - 100% .74x
Sony
A850 - 98% .74x
A900 - 100% .74x

Pentax's last 35mm Prosumer model the MZ-S wasn't even up to these standards though - 92% .74x, the highly regarded z1 was 92% and .8x

you have to go back to the MX to really see what can be done 95% @ .97x

If Pentax can get out a FF with 100% and .9 + x mag factor they will really be different from the competition

07-06-2012, 09:44 AM   #482
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QuoteOriginally posted by eddie1960 Quote
If Pentax can get out a FF with 100% and .9 + x mag factor they will really be different from the competition
As Asahiflex has written many times, the VF can and should be a or the distinguishing factor for a Pentax FF.

Think about the LX VF(s).
07-06-2012, 09:45 AM   #483
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QuoteOriginally posted by monochrome Quote
As Asahiflex has written many times, the VF can and should be a or the distinguishing factor for a Pentax FF.

Think about the LX VF(s).
As you know I really like the LX VF system. the MX actually is a little better magnification than the standard mx (but that huge sport finder WOW)
07-06-2012, 09:55 AM   #484
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QuoteOriginally posted by eddie1960 Quote
As you know I really like the LX VF system. the MX actually is a little better magnification than the standard mx (but that huge sport finder WOW)
The MX and MESuper viewfinders are simply outstanding. Alas, those bodies are too small for my comfort. (Really, the K-5 and K-01 are too small for my hands).

An LX with the FB-1 / FC-1 Finder and Grip B seems tge ideal small film camera for me, especially wearing glasses, but I've never accomdated my hands after starting on a KX (and the K2DMD and KM).

FWIW, my KM has the sharpest snap-in-focus viewfinder I've ever used. May be just my copy - but, WOW!

Pentax has some history developing excellent viewfinders. Let's hope they're looking at VF technology as well as WR, rugged, small, imaging engine - and improving autofocus

07-06-2012, 09:58 AM   #485
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QuoteOriginally posted by monochrome Quote

Pentax has some history developing excellent viewfinders. Let's hope they're looking at VF technology as well as WR, rugged, small, imaging engine - and improving autofocus
Given the K30 is Pentaprism and 100% yep I think they are looking at the VF being a distinguishing factor. nothing close to the K30 in price has a finder that nice
07-06-2012, 02:35 PM   #486
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QuoteOriginally posted by Class A Quote
Not sure whether you have noticed already; this article was referenced by sonyalpharumors.com.
Yeah, somebody told me. Interesting

To reveal my hidden evil plan ...

1. Sonyalpharumors publishes Pentax goes full frame -- CHECK
2. Sony sees Pentax go full frame -- CHECK
3. Sony walks over to Pentax HQ offering their FF sensor for a fantastic price Pentax cannot refuse -- IN PROGRESS


More seriously though, here are some sources citing the article:

Last edited by falconeye; 07-06-2012 at 03:12 PM.
07-08-2012, 12:28 AM   #487
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QuoteOriginally posted by rawr Quote
Remember, there are also film SLR's with AF systems and yet they have big bright viewfinders. Ditto FF DSLR's.

So I am not sold yet on the idea that the AF system makes a big contribution to the issue of small, dim APS-C viewfinders.

I suspect the area of semi-transparency in the main mirror is also quite modest since it doesn't need to be large.
I don't know of any autofocus film camera that has a viewfinder as large as the best manual focus film cameras.

The best manual focus film cameras had a magnification close to 0.97.

The best autofocus film cameras had a magnification close to 0.75.

Understand that because of the smaller sensor size, a 0.75 FF viewfinder will still look much larger than a 0.95 APS-C viewfinder. Because viewfinder magnification is calculated with a 50mm lens (FF or APS-C), the crop factor of the APS-C camera give a higher magnification, but a smaller overall viewfinder.

07-09-2012, 02:12 PM   #488
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I don't think the crop factor comes into play - imagine looking at an object through a 50mm lens on a K5 and an D700, it will appear larger through the .92x K5 viewfinder, but the viewfinder which frames it will be smaller than with the .72x D700. Both viewfinders are 100% but cover 100% of different image formats.
07-09-2012, 02:24 PM   #489
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QuoteOriginally posted by ihasa Quote
I don't think the crop factor comes into play - imagine looking at an object through a 50mm lens on a K5 and an D700, it will appear larger through the .92x K5 viewfinder, but the viewfinder which frames it will be smaller than with the .72x D700. Both viewfinders are 100% but cover 100% of different image formats.
That's right. The magnification advantage for a 135 full frame viewfinder comes about when comparing similar angles of view between the two formats. That is, a 50mm lens on FF will have about the same AOV as a 35mm lens on APS-C but will obviously have more magnification thanks to the longer focal length.

Last edited by TomTextura; 07-10-2012 at 10:39 AM. Reason: correct typo: change 'the 50mm lens' to 'a 50mm lens'
07-09-2012, 09:57 PM   #490
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QuoteOriginally posted by ihasa Quote
I don't think the crop factor comes into play - imagine looking at an object through a 50mm lens on a K5 and an D700, it will appear larger through the .92x K5 viewfinder, but the viewfinder which frames it will be smaller than with the .72x D700. Both viewfinders are 100% but cover 100% of different image formats.
I found someone who agrees with me. Now I can let this rest.

Seasoned Enthusiast Photographer: Breaking the Viewfinder Myth - Viewfinder Coverage & Magnification Explained

Note the Pentax models at the bottom of the page.
07-09-2012, 10:11 PM   #491
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QuoteOriginally posted by KungPOW Quote
Argh, I wish people would stop using the words "crop factor" and "magnification" in the same sentence. "Crop factor" has nothing to do with "viewfinder magnification". A 1x magnification is the same on FF and APS-C and any format for that matter. That is, a given object seen through a 50mm lens will appear to be the same size as seen with your own eye. The difference between formats lies entirely with the coverage.

A 100% coverage, 1x magnification APS-C viewfinder will appear exactly the same as a FF viewfinder with 66% coverage, 1x magnification. Does that clear everything up?

Last edited by Cannikin; 07-09-2012 at 10:35 PM.
07-10-2012, 04:09 AM   #492
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QuoteOriginally posted by Cannikin Quote
A 100% coverage, 1x magnification APS-C viewfinder will appear exactly the same as a FF viewfinder with 66% coverage, 1x magnification. Does that clear everything up?
No, while true, it is extremely misleading.

The full formula for virtual viewfinder size is

Magnification x coverage/100% / cropfactor

Of course, you can interpret (coverage/100% / cropfactor) in any way as long as the quotient remains the same. And of course, 66%/1.0 = 100%/1.5.

But your interpretation makes no sense and will confuse people.

By convention, coverage is expressed in relation to the sensor/film and we don't want to change this.

By convention, magnification is expressed in relation to a 50mm lens and even this nobody wanted to change.

Therefore, a third factor, the crop-factor, is introduced to express virtual viewfinder size (cf. formula above).

The "35-mm equivalent magnification" is (Magnification / cropfactor) and expresses magnification wrt to a lens 35-mm equivalent to 50mm. It is crucial to evaluate the ability for manual focus thru the VF.


Your statement is misleading because it assumes that an APSC and FF camera would use the same lenses while they don't.
07-10-2012, 09:05 AM   #493
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QuoteOriginally posted by falconeye Quote
By convention, magnification is expressed in relation to a 50mm lens and even this nobody wanted to change.
I want to change it to 43mm, but mainly just to be contrary.
07-10-2012, 03:42 PM   #494
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I'm still wondering if Pentax will release a FF while they currently only produce 7 FF lenses. It seems like they would need to ramp up production on new lenses, or reinstate production on old ones, otherwise a FF won't be attractive to new buyers...I mean what would be the point if you can't get lenses?
07-10-2012, 03:56 PM   #495
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QuoteOriginally posted by monochrome Quote
The MX and MESuper viewfinders are simply outstanding. Alas, those bodies are too small for my comfort. (Really, the K-5 and K-01 are too small for my hands).

An LX with the FB-1 / FC-1 Finder and Grip B seems tge ideal small film camera for me, especially wearing glasses, but I've never accomdated my hands after starting on a KX (and the K2DMD and KM).

FWIW, my KM has the sharpest snap-in-focus viewfinder I've ever used. May be just my copy - but, WOW!

Pentax has some history developing excellent viewfinders. Let's hope they're looking at VF technology as well as WR, rugged, small, imaging engine - and improving autofocus
That's me on the far right with my old LX, Sports finder, Motor drive and 28mm Shift lens. about 1983-4 I think.
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